Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study

Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study Yuanhua Ye, Jing Li, Shiguo Liu, Yang Zhao, Yanhua Wang, Yijing Chu, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1773482/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 May, 2023 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted 11 You are reading this latest preprint version Abstract Background: Patients with abnormally invasive placenta (AIP) are at high risk of massive postpartum hemorrhage. Resuscitative endovascular balloon occlusion of the aorta (REBOA) as an adjunct therapeutic strategy for hemostasis offers the obstetrician an alternative for the treatment of patients with abnormally invasive placenta. This study aimed to evaluate the role of REBOA for hemorrhage control in patients with AIP. Methods: This is a historical cohort study with prospectively collected data at a single tertiary center between January 2014 to July 2021. In total, 364 singleton pregnant AIP patients with desire to preserve uterus and delivered were separated into two groups. The study group (balloon group, n=278) underwent REBOA during cesarean section, whereas the reference group (n=86) did not undergo REBOA. Surgical details and maternal outcomes were collected. The primary outcome was estimated blood loss and the rate of uterine preservation. Results: A total of 278 [76.4%] participants experienced REBOA during cesarean section. Patients in the balloon group had less mean (SD) blood loss during cesarean section (1370.5 [752.0] ml vs. 3536.8 [1383.2] ml; P <.001) and had their uterus salvaged more often (264 [95.0%] vs. 23 [26.7%]; P <.001). These patients were also less likely to be admitted to the intensive care unit after delivery (168 [60.4%] vs. 67 [77.9%]; P =.003) and had less mean (SD) operating time (96.3 [37.6] min vs. 160.6 [45.5] min; P <.001). The rate of neonatal intensive care unit admission (176 [63.3%] vs. 52 [60.4%]; P =.70) and total mean (SD) maternal medical costs ($4925.4 [1740.7] vs. $5083.2 [1705.1]; P =0.13) did not differ between the groups. Conclusions: As a robust hemorrhage-control technique, REBOA can reduce intraoperative hemorrhage in patients with AIP. The next step is to identify associated risk factors and define REBOA inclusion criteria to identify the subgroups of AIP patients who may gain more benefits. Cesarean hysterectomy Obstetric hemorrhage Placenta accreta spectrum Abnormally invasive placenta REBOA Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Placenta accreta, or placenta accreta spectrum (PAS), is the direct attachment of chorionic villi to the uterine wall with partial or complete absence of the decidua [ 1 ], which was first described in 1927 [ 2 ]. This condition poses the highest risk of life-threatening obstetric hemorrhage if an attempt is made to forcibly remove the placenta implanted into the uterine wall. Recent studies showed that the incidence and prevalence of PAS had separately reached around 1.7 and 37.0, respectively, per 10 000 pregnancies in most high-income countries [ 3 , 4 ], coincident with the rise in cesarean deliveries worldwide, which is the most common risk factor for PAS. PAS includes both abnormal adherence of the placenta (creta, when the villi attach to the myometrium) and abnormal invasion of the placenta (AIP) including increta when the villi invade the myometrium, and percreta when the villi invade the full thickness of the myometrium [ 1 ]. Compared with creta, increta and percreta are more concerning, as they are the two main phenotypes of PAS that result in peripartum hysterectomy, maternal morbidity, and even mortality [ 5 ]. There is a consensus that cesarean hysterectomy with the placenta in situ is the appropriate measure in case of high suspicion of AIP during cesarean delivery to reduce the immediate risk of major hemorrhage and accompanying complications [ 6 ]. This indicates that a high risk of fertility loss will be common among AIP patients. It is undeniably a misfortune for patients who desire future childbirth or for those in whom uterus retention is linked with their gender identity and self-esteem [ 7 ]. Therefore, a safe alternative should be offered to these patients to salvage the uterus while simultaneously removing the implanted placenta. To achieve this goal, a reliable intraoperative hemostasis regimen is imperative, including REBOA. It is an endovascular hemorrhage control technique successfully used in emergency medicine to maintain blood flow to critical organs in patients with hemorrhagic shock with uncontrolled abdominal, pelvic, or lower extremity bleeding until hemorrhage could be definitively controlled via surgery [ 8 ]. REBOA can be also used proactively prior to hemodynamic collapse and even prior to anticipated blood loss, such as obstetric hemorrhage. Therefore, this historical cohort study aimed to evaluate the role of REBOA in the management of AIP. Methods Study population We retrospectively reviewed records of singleton pregnant AIP patients between January 2014 and July 2021. Due to the retrospective nature of the study, informed consent was waived. Inclusion criteria were (1) singleton pregnant patients with placenta increta or percreta diagnosed prenatally using transabdominal or transvaginal ultrasound examination or magnetic resonance imaging (MRI) and confirmed intraoperatively or histologically and (2) a desire to preserve uterus. Patients with missing values for demographic (e.g., number of previous cesarean delivery) or clinical characteristics (e.g., type of AIP, aortic occlusion time) were excluded. Prenatal diagnosis of AIP was based on grayscale and color Doppler (with bladder filling of 200–300 ml) showing loss of “clear zone,” abnormal placental lacunae, bladder wall interruption, myometrial thinning less than 1 mm, placental bulge, focal exophytic mass, uterovesical hypervascularity, subplacental hypervascularity, bridging vessels, or placental lacunae feeder vessels [ 9 ]. None of the involved criteria can reliably predict the extent of placental penetration [ 1 ], especially for posterior placental implantation and/or obese patients. MRI was used for reassessing the type of suspected PAS or in cases of equivocal ultrasound findings in patients at risk. Intraoperatively, placenta increta or percreta was reconfirmed in patients with chorionic villi invading the myometrium or perimetrium (uterine serosa). Surgical samples (including separated placentas, total or partial hysterectomy tissues, partial resected myometrium with or without implanted placenta) were obtained whenever possible for histopathologic confirmation. All patients were allocated to two groups: those who underwent REBOA during cesarean section (balloon group, n = 278) and those who did not undergo REBOA (reference group, n = 86). Most patients (61/86) in the reference group underwent cesarean section without aortic balloon before April 2015 when the REBOA technique was first performed in AIP patients in our tertiary referral hospital. After April 2015, REBOA did not apply in the remaining patients (25/86) in the reference group because the interventional radiology service was not available before their cesarean sections. A total of 281 patients underwent lower abdominal aortic balloon before cesarean section; however, three balloons were not inflated during surgeries at the surgeon’s discretion because their placental invasion was not as severe as initially thought. Excluding these patients, 278 remain in the balloon group (Fig. 1 ). Management protocol After hospital admission, written informed consent was obtained from all patients, thoroughly acknowledging their clinical condition and the latent risks and uncertain benefits of various treatments. The delivery date was determined by multidisciplinary counseling for each case based on ultrasound and MRI results, prenatal vaginal bleeding, uterine contractions, and fetal maturity. Before performing cesarean section, the patients in the balloon group were sent to the interventional radiology surgical suite. Right femoral arterial puncture was performed under local anesthesia by an interventional radiologist using a 12.0-F occlusion balloon catheter (MAXI-LD 20⋅40 110CM REF: 4162040L, Cordis Corp., Miami Lakes, FL, USA) with a 0.035-in stiff guidewire (THSCF-35-145-1.5-ROSEN; Cook) placed using a 12.0-F introducer sheath (Ultimum EV Hemostasis; St. Jude Medical., Minnetonka, MN, USA). The balloon was accurately placed under the level of the renal artery at the distal abdominal aorta and above the bifurcation of the abdominal aorta under fluoroscopic guidance. Simultaneously, using trial balloon inflation, accurate placement of the balloon was confirmed as well as the exact volume of 0.9% saline needed to inject into the balloon to obtain ideal vascular occlusion (Video S1 and S2). Subsequently, the patients were transferred from the interventional radiology suite to the operative theater for cesarean section under general anesthesia. A multidisciplinary team performed all cesarean sections. Hysterectomy was performed if the operating team confirmed that preserving the uterus was unfeasible. Bilateral ureteral stents were inserted before or during the operation if necessary. In the reference group, following fetal delivery, a tourniquet was usually used to tie around the cervix to help reduce bleeding. Usually, we still had no clear surgical field because of excessive bleeding (Fig. 2 A). On the contrary, in the balloon group, in case of fetal delivery and cord clamping, the aortic balloon was inflated with 0.9% saline to reduce blood supply to the operating field to obtain a drier operating field (Fig. 2 B). Before trying to remove the placenta, the bladder flap was dissected thoroughly from the lower anterior uterine surface (surpassing the internal os level). Following the removal of the placenta, a parallel traversal compressing suture technique (Fig. 3 ) was applied to stop bleeding, ligate the blood vessels, and remodel the uterus. During surgery, every 10–15 min of occlusion of the aorta, there would be a 1-min deflating time of the balloon to resuscitate ischaemic organs until ideal haemostasis was observed. After the operation, the sheath and occlusion balloon catheter would be removed 4–6 h later if vital signs were stable, and lower extremity perfusion was assessed before, during, and after balloon occlusion and after sheath removal. Otherwise, once continuous uterine bleeding was confirmed, bilateral uterine artery embolization or hysterectomy would be performed depending on the situation, e.g., non-life-threatening or uncontrolled bleeding. Low-molecular-weight heparin was prophylactically administered to all patients in both groups 12 h after surgery to reduce the risk of venous thromboembolism. The following parameters were recorded: demographic data, estimated blood loss, transfusion of packed red blood cells, operation duration, hysterectomy performed, bilateral uterine artery embolization required, aortic occlusion time, femoral artery cannulation time (time from the percutaneous femoral artery puncture to successful placement of the introducer sheath), indwelling sheath duration (femoral artery cannulation time), radiographic exposure (mGy) and screening time, total maternal care costs, intensive care unit (ICU) and neonatal ICU (NICU) admission, and AIP surgery- and balloon catheter-related complications. Statistical analyses Continuous variables were expressed as mean (SD) and compared using independent samples t test, while discrete variables were expressed as counts or percentages and analyzed using Pearson’s chi-squared test or Fisher’s exact test, as appropriate. To define the risk factors of thrombosis, univariate logistic regression was performed and expressed as odds ratios (ORs) with their 95% confidence intervals (CIs). IBM SPSS Statistics for Mac version 25.0 (IBM Corp., Armonk, NY, USA) was used for all analyses, and values of P < .05 were considered statistically significant. Results Patient demographics No significant differences in maternal age, gestational age at delivery, gravidity, parity, number of previous cesarean deliveries, grade of placenta previa (minor or major), and type of AIP were found between the study groups (Table 1 ). Table 1 Demographic and obstetric characteristics of patients Balloon group ( n = 278) Reference group ( n = 86) p Value Maternal age, mean (SD), y 33.9 (4.8) 34.1 (3.8) .84 * Gestational age at delivery, mean (SD), w 35.9 (1.9) 36.1 (1.6) .55 * Gravidity, mean (SD) 4.3 (1.9) 4.4 (1.7) .25 * Parity, mean (SD) 1.2 (0.4) 1.3 (0.5) .06 * Number of previous cesarean deliveries, median (range) 1 (0–3) 1 (0–2) .45 * Preoperative bleeding 81 (29.1%) 23 (26.7%) .78 # Combined placenta previa .49 # Major 207 (74.4%) 65 (75.6%) Minor 59 (21.2%) 15 (17.4%) None 12 (4.3%) 6 (7.0%) Type of AIP .23 # Increta 203 (73.0%) 57 (66.3%) Percreta 75 (27.0%) 29 (33.7%) Data are given as mean ± standard deviation, number (percentage), or median (range). P < .05 was considered statistically significant. * Kruskal-Walis test # Pearson’s chi-squared test Comparisons of patient outcomes In the balloon group, all patients successfully underwent occlusion balloon placement before delivery, and all balloons were well inflated following cesarean section. The median time taken for attempted femoral artery cannulation was 130 s (range, 75–1265 s). The mean (SD) fluoroscopy time range was 2.8 [1.3] s (range, 1.4–5.6 s). The mean estimated maternal radiation exposure was 2.3 [1.0] (range, 1.2–4.6) mGy, which is considered safe in pregnancy.[ 10 ] Mean (SD) estimated blood loss during surgery were 1370.5.4 [752.0] ml and 3536.8 [1383.2] ml in the balloon and reference groups, respectively ( P < .001) (Fig. 4 A). Accordingly, fewer units of packed red blood cells were transfused in the balloon group than in the reference group (3.0 [4.0] vs. 13.8 [6.9], P < .001, respectively) (Fig. 4 B). There were 264/278 (95.0%) and 23/86 (26.7%) patients preserving their uterus successfully in the balloon and reference groups, respectively ( P < .001) (Fig. 4 C). The mean (SD) operation duration in the balloon group was significantly shorter than that in the reference group (96.3 [37.6] min vs. 160.6 [45.5] min) ( P < .001) (Fig. 4 D). Patients in the balloon group had a lower ICU admission rate (168/278, 60.4%) than did their counterparts in the reference group (67/86, 77.9%, P = .003) (Fig. 2 E). The NICU admission rate showed no significant difference between the groups (176/278 (63.3%) vs 52/86 (60.4%), P = .70) (Fig. 4 F). No difference in mean (SD) total maternal medical costs was found between the groups ( $ 4925.4 [1740.7] vs $ 5083.2 [1705.1], P = 0.13) (Fig. 4 G). Surgery-related and catheterization-related complications There was no sepsis, peritonitis, fistula, acute pulmonary edema, acute renal failure, pulmonary embolism, or death in either group. For other severe morbidities, including reoperations (repeat laparotomy to perform hysterectomy or hemostasis, abdominal wall hematoma removal, uterine artery embolization, and thromboembolectomy) and thromboembolic events (deep vein thrombosis and arterial thrombosis), bowel or urinary tract injury also presented no differences between groups (Fig. 4 H). A summary of the explicit severe maternal morbidities is provided in Table 2 . In the balloon group, four of eight patients who had femoral arterial thrombosis underwent thromboembolectomy. The remaining four patients were successfully managed with thrombolytic therapy. It is clear the frequency of thrombolysis and thromboembolectomy have a marked increase with the balloon procedures. Table 2 Cases of severe maternal morbidity in reference and balloon group Reoperations Thromboembolic events Injury to adjacent organs Total (%) Reference group Abdominal wall hematoma removal ⋅ 3 laparotomy with hysterectomy ⋅ 1 Deep vein thrombosis ⋅ 3 Bowel injury ⋅ 1 Urinary tract injury ⋅ 4 14.0 (12/86) Balloon group Abdominal wall hematoma removal ⋅ 3 laparotomy with hysterectomy ⋅ 3 Thromboembolectomy ⋅ 4 Deep vein thrombosis ⋅ 7 Arterial thrombosis ⋅ 8 Urinary tract injury ⋅ 11 12.9 (36/278) In the balloon group, the mean (SD) occlusion time was 14.6 [8.3] (range, 5–54) min. Overall, 7.19% (20/278) of the patients experienced interventional radiology-related complications. Of the 278 patients, regular uterine contractions after the intervention was detected in 12 (4.32%), local catheter-related infections in two (0.72%), local hemorrhage in three (1.08%), and hematomas in three (1.08%) patients. Risk factors for thrombosis From the perspective of clinical expertise, we selected aortic occlusion time, estimated blood loss, operation duration, femoral artery cannulation time, and indwelling sheath duration as predictable variables that may be connected with femoral arterial thrombosis. On the univariate logistic regression analysis (Table 3 ), none of these characteristics were associated with an increased thrombotic risk at the femoral site. Table 3 Predictors of thrombotic risk in the femoral location in the balloon group Characteristics Femoral arterial thrombosis Unadjusted OR (95% CI) p -value Yes, n = 8 No, n = 270 Aortic occlusion time (m) 13 (10–30) 12 (5–54) 1.06 (0.95–1.18) 0.30* Estimated blood loss (ml) 1200 (500–3500) 1000 (400–5000) 0.99 (0.98–1.00) 0.09* Operation duration (m) 68 (60–235) 90 (42–285) 1.01 (0.98–1.03) 0.59* Femoral artery cannulation time (s) 140 (90–775) 130 (75–1265) 0.98 (0.95–1.00) 0.21* Indwelling sheath duration(h) 7.5 (4.0–26.0) 7.5 (4.5–30.0) 0.99 (0.95–1.00) 0.60* Discussion Obstetric hemorrhage is the principal cause of maternal morbidity and mortality worldwide [ 11 ]. AIP is one of the most likely obstetrical factors that cause massive postpartum hemorrhage. Therefore, managing AIP by effectively reducing blood loss and associated maternal morbidity and mortality rates is essential. Although ultrasonography combined with MRI has shown satisfactory sensitivity and specificity in the prenatal diagnosis of AIP [ 12 ], we excluded three patients whose intraoperative findings were incompatible with the prenatal findings. The balloon was not inflated during the operation in these three patients. From this point, the balloon was prophylactically placed, rather than prophylactically inflated, in patients with the highest suspicion of AIP to avoid unnecessary risks associated with aortic occlusion because of false-positive prenatal diagnoses. Unlike REBOA used in trauma and emergency medicine, prophylactic placement of endovascular balloon occlusion catheter can be a fundamental component of the surgical AIP management. Indeed, REBOA can be deployed in pregnant women with established hemorrhagic shock during an emergency peripartum hysterectomy as a rescue maneuver to maintain the stability of the circulatory system [ 13 ]. To this day, the safety and efficacy of REBOA in women with a prenatal diagnosis of AIP are yet to be confirmed[ 14 ]. Published results have been conflicting, ranging from affirmative [ 15 ] to skeptical [ 16 ] to inconclusive [ 17 ]. However, most studies involved small numbers of patients or did not distinguish abnormal adherent placenta (known as creta) from AIP (known as increta and percreta), despite the latter two conditions being the main causes of massive obstetric hemorrhage and infertility[ 18 ]. Given the lack of effective hemostasis, even handled by an experienced multidisciplinary team of surgeons, peripartum hysterectomy presented considerable risks because of possible pelvic adhesions attributed to previous surgery, enlarged blood supply to the pregnant uterus, and possible invasion to the parametrium in cases of placenta percreta. Therefore, morbidities and mortality associated with surgery for AIP are significant, and perioperative complications are common [ 4 , 19 ]. REBOA provides time and opportunity for surgeons to perform surgical deliberately, reduce the complexity of the operation, and eventually lower the technical challenge to manage AIP. We did not find significant differences in rates of urinary tract or bowel injury between the groups. This may be due to the fact that all patients were managed by an experienced multidisciplinary care team and each group has small number of cases with complications. REBOA deployment-related complications are another concern, including those related to femoral artery cannulation, balloon positioning and removal, and thromboembolic events. Excluding other mild complications, arterial thrombosis is one of the most common severe complications of REBOA, with a reported incidence of 5% [ 20 ]. Lower limb ischemia, pseudo-aneurysm formation, ischemic femoral nerve injury, and maternal death due to abdominal aortic dissection have been reported [ 21 ]. Obstetric hemorrhage offers expanding indications for REBOA, and the exact incidence and predictors of each complication remain unclear. In this study, there were 8/278 (2.88%) cases of arterial thrombosis in the balloon group, but no vascular injuries or lower limb ischemic episodes. It appears that percutaneous cannulation disrupts the integrity of the vessel wall, triggering thrombus formation. Women generally have small-caliber arteries, a fact that is independently associated with arterial obstruction [ 22 ], and pregnancy itself is a risk factor for hypercoagulability. These patients may be more vulnerable to thrombosis because of the administration of tranexamic acid or other coagulation factors. To determine risk factors for arterial thrombosis, univariate logistic regression analysis was implemented; however, no relative variables were found, despite some studies having reported longer catheter dwell times, prolonged femoral artery cannulation times, and multiple punctures for catheter insertion to be associated with thrombosis or embolism [ 23 ]. The small number of arterial thrombosis cases may be a reason; therefore, multicenter prospective studies are needed to confirm predictors of thrombotic risk of REBOA in obstetrics. Although long occlusion time (4–6 h) of the infrarenal aorta is possible [ 24 ], our strategy is intermittent deflation of the balloon to relieve organic ischemia and removing the catheter and sheath as soon as possible while the vital signs remain stable. As anticipated, common femoral artery cannulation performed by skilled hands and smaller introducer sheaths for REBOA may be associated with fewer access-related complications [ 25 ]. Considering REBOA-related complications, most findings generated from their application in trauma patients with hemorrhagic shock. Although the small number of cases in our study makes it unfeasible to draw definite conclusions, the patients should be informed of the higher risk for arterial thrombosis. Moreover, AIP patients should be counseled on the increased likelihood of recurrence in subsequent pregnancies before choosing conservative treatment, for the recurrence among women with PAS who retained their uterus is 13.3–29.6% [ 26 , 27 ]. The next step should be to identify associated risk factors and define REBOA inclusion criteria to identify the subgroups of AIP patients who gain more benefits from REBOA. In this study, 14 patients in the balloon group failed to retain their uteri. Even with the support of REBOA, it remains challenging to prejudge the chances of preserving the uterus successfully at the point when the peritoneum is opened. REBOA-assisted cesarean section remains a novel method for AIP patients, and the intraoperative strategy and patient outcomes also need to be improved over time. Including expenditures related to vascular and interventional radiology processes, the total medical costs in the balloon group showed no significant difference with those in the reference group. Undoubtedly, the decreased requirement for blood product lowered the total costs of medical care. Lower need for blood transfusion and ICU admission in the balloon group means that REBOA is particularly suitable for regions where blood products are relatively restrained. An alternative interventional radiologic modality used in women with PAS is occlusion of the internal iliac arteries. Nevertheless, this process appears to be more debatable regarding its benefits in terms of hemostasis than the benefits associated with aortic occlusion [ 28 , 29 ]. This is most likely explained by the extensive collateral blood supply of the pelvis. Randomized controlled studies are needed to examine the risks and benefits of REBOA compared with those of internal iliac artery occlusion. What is certain is that REBOA only requires cannulation of a single common femoral artery, and the exposure dose to the fetus is considered lower and is, therefore, acceptable [ 10 ]. This study has some limitations. This study has single-center and retrospective design. Moreover, follow-up data on future pregnancies following this intervention is still not available. Without knowledge of how these patients do in future pregnancies, the role of REBOA in the preservation of fertility in AIP patients still cannot be revealed. In addition, skills of the REBOA operator were not evaluated. A future multicenter prospective study is needed to expand on this innovative approach. Finally, the cost-effectiveness analysis is likely only applicable to China. Other health care systems may or may not see a benefit. Conclusions This study demonstrated that REBOA, as an adjunct therapeutic strategy for hemostasis, can help to reduce intraoperative blood loss and salvage the uterus in AIP patients. Abbreviations AIP abnormally invasive placenta PAS placenta accreta spectrum REBOA resuscitative endovascular balloon occlusion of the aorta ICU intensive care unit NICU neonatal intensive care unit MRI magnetic resonance imaging CI, confidence interval OR, odds ratio. Declarations Acknowledgments We are deeply grateful to the medical staff at the Obstetrics and Gynecology Department of The Affiliated Hospital of Qingdao University, Qingdao, China. We want to thank all the patients who participated in this study. Author contributions YY, JL, and JZ were involved in the conception and design of the study. YY, JL, WP, SL, and JZ were involved in the planning of the study. YY, JL, WP, SL, YZ, CY and YW were involved in data collection and carrying out of the study. SL, YZ, CY, CL, and YW were involved in the analysis of the project. YY, JL, and JZ primarily wrote the manuscript, with editing contributions from all authors. All the authors read and approved the final manuscript. Funding This work was supported by the Natural Science Foundation of Shandong Province under Grant ZR2019MH127. The funders of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report. Availability of data and materials All data generated or analysed during this study are included in this published article and its supplementary information files. Ethical approval and consent to participate All methods were performed in accordance with the relevant guidelines and regulations. This study was approved by the local ethics committee of the Affiliated Hospital of Qingdao University(protocol number: QYFY WZLL 25523 on April 19, 2015), which waived the need for written informed consent given the retrospective nature of the study and the use of anonymized data from hospital records. Consent for publication Not applicable. Competing interests The authors report no conflict of interest. References Jauniaux E, Collins S, Burton GJ: Placenta accreta spectrum: pathophysiology and evidence-based anatomy for prenatal ultrasound imaging . Am J Obstet Gynecol 2018, 218 (1):75–87. Forster DS: A Case of Placenta Accreta . Can Med Assoc J 1927, 17 (2):204–7. Mogos MF, Salemi JL, Ashley M, Whiteman VE, Salihu HM: Recent trends in placenta accreta in the United States and its impact on maternal - fetal morbidity and healthcare - associated costs , 1998 –2011. 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Nieto-Calvache AJ, Hidalgo-Cardona A, Lopez-Giron MC, Rodriguez F, Ordonez C, Garcia AF, Mejia M, Pabon-Parra MG, Burgos-Luna JM: Arterial thrombosis after REBOA use in placenta accreta spectrum: a case series . J Matern-Fetal Neo M 2020. Brenner M, Bulger EM, Perina DG, Henry S, Kang CS, Rotondo MF, Chang MC, Weireter LJ, Coburn M, Winchell RJ et al : Joint statement from the American College of Surgeons Committee on Trauma (ACS COT) and the American College of Emergency Physicians (ACEP) regarding the clinical use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) . Trauma Surg Acute Care Open 2018, 3 (1):e000154. Romagnoli A, Teeter W, Pasley J, Hu P, Hoehn M, Stein D, Scalea T, Brenner M: Time to aortic occlusion: It's all about access . J Trauma Acute Care 2017, 83 (6):1161–4. Mullen C, Battarbee AN, Ernst LM, Peaceman AM: Occult Placenta Accreta: Risk Factors, Adverse Obstetrical Outcomes, and Recurrence in Subsequent Pregnancies . Am J Perinatol 2019, 36 (5):472–5. Baldwin HJ, Nippita TA, Torvaldsen S, Ibiebele I, Ford JB, Patterson JA: Outcomes of Subsequent Births After Placenta Accreta Spectrum . Obstet Gynecol 2020, 136 (4):745–55. Angileri SA, Mailli L, Raspanti C, Ierardi AM, Carrafiello G, Belli AM: Prophylactic occlusion balloon placement in internal iliac arteries for the prevention of postpartum haemorrhage due to morbidly adherent placenta: short term outcomes . Radiol Med 2017, 122 (10):798–806. Yu SCH, Cheng YKY, Tse WT, Sahota DS, Chung MY, Wong SSM, Chan OK, Leung TY: Perioperative prophylactic internal iliac artery balloon occlusion in the prevention of postpartum hemorrhage in placenta previa: a randomized controlled trial . Am J Obstet Gynecol 2020, 223 (1):117 e1- e13. Additional Declarations No competing interests reported. Supplementary Files Originaldata.xlsx VideoS1.avi Video S1 and S2: Position confirmation of the balloon catheter using fluoroscopy. VideoS2.avi Video S1 and S2: Position confirmation of the balloon catheter using fluoroscopy. Cite Share Download PDF Status: Published Journal Publication published 10 May, 2023 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted Editorial decision: Major revision 05 Sep, 2022 Reviews received at journal 31 Aug, 2022 Reviewers agreed at journal 20 Aug, 2022 Reviews received at journal 18 Aug, 2022 Reviewers agreed at journal 06 Aug, 2022 Reviewers agreed at journal 06 Aug, 2022 Reviewers invited by journal 03 Aug, 2022 Editor assigned by journal 27 Jul, 2022 Editor invited by journal 23 Jul, 2022 Submission checks completed at journal 23 Jul, 2022 First submitted to journal 19 Jun, 2022 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-1773482","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":123390221,"identity":"9bd34114-8b45-4e3c-88aa-2090433ea65d","order_by":0,"name":"Yuanhua Ye","email":"","orcid":"","institution":"The Affiliated Hospital of Qingdao University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yuanhua","middleName":"","lastName":"Ye","suffix":""},{"id":123390225,"identity":"19245909-dfd8-4350-8058-fb660d36b1fe","order_by":1,"name":"Jing Li","email":"","orcid":"","institution":"The Affiliated Hospital of Qingdao University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jing","middleName":"","lastName":"Li","suffix":""},{"id":123390227,"identity":"2e376916-5f42-4145-a540-49d6565af26e","order_by":2,"name":"Shiguo Liu","email":"","orcid":"","institution":"The Affiliated Hospital of Qingdao University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shiguo","middleName":"","lastName":"Liu","suffix":""},{"id":123390228,"identity":"29608077-6a15-41ee-b4e0-1135b2b5a561","order_by":3,"name":"Yang Zhao","email":"","orcid":"","institution":"The Affiliated Hospital of Qingdao University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Zhao","suffix":""},{"id":123390229,"identity":"0aa3f958-ce9d-467d-aea8-bb064974b534","order_by":4,"name":"Yanhua Wang","email":"","orcid":"","institution":"The Affiliated Hospital of Qingdao 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Affiliated Hospital of Qingdao University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Jun","middleName":"","lastName":"Zhou","suffix":""}],"badges":[],"createdAt":"2022-06-19 12:29:05","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-1773482/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-1773482/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12884-023-05649-8","type":"published","date":"2023-05-10T20:46:30+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":24291485,"identity":"6e5b9860-d156-4bf2-ae3f-5542b7f5e994","added_by":"auto","created_at":"2022-07-25 14:26:56","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":145016,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFlow chart of study population selection\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/e8dc5e9fb2ca84c6124b1499.jpg"},{"id":24291489,"identity":"9515fa3d-8785-4296-b108-2ea79aa00761","added_by":"auto","created_at":"2022-07-25 14:26:57","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":2324762,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eParallel traversal compressing suture technique.\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eA: \u003c/strong\u003eThis novel parallel traversal compressing suture technique was used to strengthen the weak uterine lower segment without contractile force after placental dissection, and the corresponding blood vessels were ligated for hemostasis. \u003cstrong\u003eB:\u003c/strong\u003e Diagrammatic sketch of parallel traversal compressing suture technique.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/686bd61aa1c007de3800d277.png"},{"id":24291488,"identity":"bb04bbd7-5357-4614-accb-3ff48d75fb3e","added_by":"auto","created_at":"2022-07-25 14:26:57","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2963857,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eAIP surgical field with or without REBOA.\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e Performing cesarean hysterectomy in a bloody operating field without REBOA. \u003cstrong\u003eB.\u003c/strong\u003e Inflation of the aortic balloon after umbilical cord clamping to provide a clear surgical field.\u003c/p\u003e\u003cp\u003eREBOA, resuscitative endovascular balloon occlusion of the aorta\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/5a97c94b6d977859d6dac921.png"},{"id":24291487,"identity":"352e55de-2125-4e3e-90e8-61a06c584682","added_by":"auto","created_at":"2022-07-25 14:26:56","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":2344780,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparisons of patient outcomes between the reference and balloon groups.\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003e Intraoperative estimated blood loss in the balloon group compared with the reference group; \u003cem\u003eP\u003c/em\u003e\u0026lt;.001, independent-samples t test. \u003cstrong\u003eB.\u003c/strong\u003e Comparison of PRBC transfusions between the balloon and reference groups.\u003cem\u003e P\u003c/em\u003e\u0026lt;.001, Mann–Whitney U test. \u003cstrong\u003eC. \u003c/strong\u003eRate of uterine preservation in the balloon group compared with that in the reference group; \u003cem\u003eP\u003c/em\u003e\u0026lt;.001, Chi-squared test. \u003cstrong\u003eD.\u003c/strong\u003e Comparison of operation duration between the balloon and reference groups;\u003cem\u003e P\u003c/em\u003e\u0026lt;.001, independent-samples t test. \u003cstrong\u003eE.\u003c/strong\u003e Rate of ICU admission in the balloon group compared with that in the reference group; \u003cem\u003eP\u003c/em\u003e=.003, Chi-squared test. \u003cstrong\u003eF.\u003c/strong\u003e Rate of NICU admission in the balloon group compared with that in the reference group; \u003cem\u003eP\u003c/em\u003e=.70, Chi-squared test. \u003cstrong\u003eG.\u003c/strong\u003e Comparison of total medical costs between the balloon and reference groups;\u003cem\u003e P\u003c/em\u003e=.13, independent-samples t test. \u003cstrong\u003eH.\u003c/strong\u003e Rates of thromboembolic events, reoperations, and bowel or urinary tract injury in the balloon group compared with that in the reference group; \u003cem\u003eP\u003c/em\u003e=.707, \u003cem\u003eP\u003c/em\u003e\u0026gt;.999, \u003cem\u003eP\u003c/em\u003e=.399, respectively, Fisher’s exact test.\u003c/p\u003e\u003cp\u003eICU, intensive care unit; NICU, neonatal intensive care unit.\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/53a3755c5b3d5d94507c362d.jpg"},{"id":44728394,"identity":"f515cbac-1166-439b-9a55-e151497ae01d","added_by":"auto","created_at":"2023-10-16 21:03:02","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4369002,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/e3ff641d-1079-4296-a32f-389a61d3425a.pdf"},{"id":24291490,"identity":"33ad2a2f-33cb-4fad-aa06-183f385d6ae2","added_by":"auto","created_at":"2022-07-25 14:26:57","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":7682879,"visible":true,"origin":"","legend":"","description":"","filename":"Originaldata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/0215c496b483540169a46261.xlsx"},{"id":24291491,"identity":"25063e29-40c9-4271-97fc-9f7610787c37","added_by":"auto","created_at":"2022-07-25 14:26:57","extension":"avi","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":16593408,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVideo S1 and S2: Position confirmation of the balloon catheter using fluoroscopy.\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"VideoS1.avi","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/187c621bdcad1459fef2f0d2.avi"},{"id":24291975,"identity":"5c251553-2156-44e5-be4e-ba814b76e7f9","added_by":"auto","created_at":"2022-07-25 14:31:57","extension":"avi","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":16593408,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eVideo S1 and S2: Position confirmation of the balloon catheter using fluoroscopy.\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"VideoS2.avi","url":"https://assets-eu.researchsquare.com/files/rs-1773482/v1/d5bceef4ac31460df9e88de4.avi"}],"financialInterests":"No competing interests reported.","formattedTitle":"Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study","fulltext":[{"header":"Background","content":"\u003cp\u003ePlacenta accreta, or placenta accreta spectrum (PAS), is the direct attachment of chorionic villi to the uterine wall with partial or complete absence of the decidua [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], which was first described in 1927 [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. This condition poses the highest risk of life-threatening obstetric hemorrhage if an attempt is made to forcibly remove the placenta implanted into the uterine wall. Recent studies showed that the incidence and prevalence of PAS had separately reached around 1.7 and 37.0, respectively, per 10 000 pregnancies in most high-income countries [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], coincident with the rise in cesarean deliveries worldwide, which is the most common risk factor for PAS.\u003c/p\u003e \u003cp\u003ePAS includes both abnormal adherence of the placenta (creta, when the villi attach to the myometrium) and abnormal invasion of the placenta (AIP) including increta when the villi invade the myometrium, and percreta when the villi invade the full thickness of the myometrium [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Compared with creta, increta and percreta are more concerning, as they are the two main phenotypes of PAS that result in peripartum hysterectomy, maternal morbidity, and even mortality [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThere is a consensus that cesarean hysterectomy with the placenta in situ is the appropriate measure in case of high suspicion of AIP during cesarean delivery to reduce the immediate risk of major hemorrhage and accompanying complications [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This indicates that a high risk of fertility loss will be common among AIP patients. It is undeniably a misfortune for patients who desire future childbirth or for those in whom uterus retention is linked with their gender identity and self-esteem [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Therefore, a safe alternative should be offered to these patients to salvage the uterus while simultaneously removing the implanted placenta.\u003c/p\u003e \u003cp\u003eTo achieve this goal, a reliable intraoperative hemostasis regimen is imperative, including REBOA. It is an endovascular hemorrhage control technique successfully used in emergency medicine to maintain blood flow to critical organs in patients with hemorrhagic shock with uncontrolled abdominal, pelvic, or lower extremity bleeding until hemorrhage could be definitively controlled via surgery [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. REBOA can be also used proactively prior to hemodynamic collapse and even prior to anticipated blood loss, such as obstetric hemorrhage. Therefore, this historical cohort study aimed to evaluate the role of REBOA in the management of AIP.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy population\u003c/h2\u003e \u003cp\u003eWe retrospectively reviewed records of singleton pregnant AIP patients between January 2014 and July 2021. Due to the retrospective nature of the study, informed consent was waived. Inclusion criteria were (1) singleton pregnant patients with placenta increta or percreta diagnosed prenatally using transabdominal or transvaginal ultrasound examination or magnetic resonance imaging (MRI) and confirmed intraoperatively or histologically and (2) a desire to preserve uterus. Patients with missing values for demographic (e.g., number of previous cesarean delivery) or clinical characteristics (e.g., type of AIP, aortic occlusion time) were excluded.\u003c/p\u003e \u003cp\u003ePrenatal diagnosis of AIP was based on grayscale and color Doppler (with bladder filling of 200\u0026ndash;300 ml) showing loss of \u0026ldquo;clear zone,\u0026rdquo; abnormal placental lacunae, bladder wall interruption, myometrial thinning less than 1 mm, placental bulge, focal exophytic mass, uterovesical hypervascularity, subplacental hypervascularity, bridging vessels, or placental lacunae feeder vessels [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. None of the involved criteria can reliably predict the extent of placental penetration [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], especially for posterior placental implantation and/or obese patients. MRI was used for reassessing the type of suspected PAS or in cases of equivocal ultrasound findings in patients at risk. Intraoperatively, placenta increta or percreta was reconfirmed in patients with chorionic villi invading the myometrium or perimetrium (uterine serosa). Surgical samples (including separated placentas, total or partial hysterectomy tissues, partial resected myometrium with or without implanted placenta) were obtained whenever possible for histopathologic confirmation.\u003c/p\u003e \u003cp\u003eAll patients were allocated to two groups: those who underwent REBOA during cesarean section (balloon group, n\u0026thinsp;=\u0026thinsp;278) and those who did not undergo REBOA (reference group, n\u0026thinsp;=\u0026thinsp;86). Most patients (61/86) in the reference group underwent cesarean section without aortic balloon before April 2015 when the REBOA technique was first performed in AIP patients in our tertiary referral hospital. After April 2015, REBOA did not apply in the remaining patients (25/86) in the reference group because the interventional radiology service was not available before their cesarean sections. A total of 281 patients underwent lower abdominal aortic balloon before cesarean section; however, three balloons were not inflated during surgeries at the surgeon\u0026rsquo;s discretion because their placental invasion was not as severe as initially thought. Excluding these patients, 278 remain in the balloon group (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e\u003cspan type=\"BoldItalic\" class=\"BoldItalic\" name=\"Emphasis\"\u003eManagement protocol\u003c/span\u003e\u003c/h2\u003e \u003cp\u003e After hospital admission, written informed consent was obtained from all patients, thoroughly acknowledging their clinical condition and the latent risks and uncertain benefits of various treatments. The delivery date was determined by multidisciplinary counseling for each case based on ultrasound and MRI results, prenatal vaginal bleeding, uterine contractions, and fetal maturity.\u003c/p\u003e \u003cp\u003eBefore performing cesarean section, the patients in the balloon group were sent to the interventional radiology surgical suite. Right femoral arterial puncture was performed under local anesthesia by an interventional radiologist using a 12.0-F occlusion balloon catheter (MAXI-LD 20\u0026sdot;40 110CM REF: 4162040L, Cordis Corp., Miami Lakes, FL, USA) with a 0.035-in stiff guidewire (THSCF-35-145-1.5-ROSEN; Cook) placed using a 12.0-F introducer sheath (Ultimum EV Hemostasis; St. Jude Medical., Minnetonka, MN, USA). The balloon was accurately placed under the level of the renal artery at the distal abdominal aorta and above the bifurcation of the abdominal aorta under fluoroscopic guidance. Simultaneously, using trial balloon inflation, accurate placement of the balloon was confirmed as well as the exact volume of 0.9% saline needed to inject into the balloon to obtain ideal vascular occlusion (Video S1 and S2). Subsequently, the patients were transferred from the interventional radiology suite to the operative theater for cesarean section under general anesthesia.\u003c/p\u003e \u003cp\u003eA multidisciplinary team performed all cesarean sections. Hysterectomy was performed if the operating team confirmed that preserving the uterus was unfeasible. Bilateral ureteral stents were inserted before or during the operation if necessary. In the reference group, following fetal delivery, a tourniquet was usually used to tie around the cervix to help reduce bleeding. Usually, we still had no clear surgical field because of excessive bleeding (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). On the contrary, in the balloon group, in case of fetal delivery and cord clamping, the aortic balloon was inflated with 0.9% saline to reduce blood supply to the operating field to obtain a drier operating field (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). Before trying to remove the placenta, the bladder flap was dissected thoroughly from the lower anterior uterine surface (surpassing the internal os level). Following the removal of the placenta, a parallel traversal compressing suture technique (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) was applied to stop bleeding, ligate the blood vessels, and remodel the uterus.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eDuring surgery, every 10\u0026ndash;15 min of occlusion of the aorta, there would be a 1-min deflating time of the balloon to resuscitate ischaemic organs until ideal haemostasis was observed. After the operation, the sheath and occlusion balloon catheter would be removed 4\u0026ndash;6 h later if vital signs were stable, and lower extremity perfusion was assessed before, during, and after balloon occlusion and after sheath removal. Otherwise, once continuous uterine bleeding was confirmed, bilateral uterine artery embolization or hysterectomy would be performed depending on the situation, e.g., non-life-threatening or uncontrolled bleeding. Low-molecular-weight heparin was prophylactically administered to all patients in both groups 12 h after surgery to reduce the risk of venous thromboembolism.\u003c/p\u003e \u003cp\u003eThe following parameters were recorded: demographic data, estimated blood loss, transfusion of packed red blood cells, operation duration, hysterectomy performed, bilateral uterine artery embolization required, aortic occlusion time, femoral artery cannulation time (time from the percutaneous femoral artery puncture to successful placement of the introducer sheath), indwelling sheath duration (femoral artery cannulation time), radiographic exposure (mGy) and screening time, total maternal care costs, intensive care unit (ICU) and neonatal ICU (NICU) admission, and AIP surgery- and balloon catheter-related complications.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e\u003cspan type=\"BoldItalic\" class=\"BoldItalic\" name=\"Emphasis\"\u003eStatistical analyses\u003c/span\u003e\u003c/h2\u003e \u003cp\u003eContinuous variables were expressed as mean (SD) and compared using independent samples \u003cem\u003et\u003c/em\u003e test, while discrete variables were expressed as counts or percentages and analyzed using Pearson\u0026rsquo;s chi-squared test or Fisher\u0026rsquo;s exact test, as appropriate. To define the risk factors of thrombosis, univariate logistic regression was performed and expressed as odds ratios (ORs) with their 95% confidence intervals (CIs). IBM SPSS Statistics for Mac version 25.0 (IBM Corp., Armonk, NY, USA) was used for all analyses, and values of \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05 were considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e\u003cspan type=\"BoldItalic\" class=\"BoldItalic\" name=\"Emphasis\"\u003ePatient demographics\u003c/span\u003e\u003c/h2\u003e \u003cp\u003eNo significant differences in maternal age, gestational age at delivery, gravidity, parity, number of previous cesarean deliveries, grade of placenta previa (minor or major), and type of AIP were found between the study groups (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic and obstetric characteristics of patients\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBalloon group (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;278)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eReference group (\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;86)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMaternal age, mean (SD), y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33.9 (4.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34.1 (3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.84\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGestational age at delivery, mean (SD), w\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35.9 (1.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36.1 (1.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.55\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGravidity, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.3 (1.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.4 (1.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.25\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParity, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.2 (0.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.3 (0.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.06\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNumber of previous cesarean deliveries, median (range)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (0\u0026ndash;3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (0\u0026ndash;2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.45\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e81 (29.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23 (26.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.78\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCombined placenta previa\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.49\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMajor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e207 (74.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e65 (75.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMinor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59 (21.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15 (17.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (7.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of AIP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.23\u003csup\u003e#\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIncreta\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e203 (73.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57 (66.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePercreta\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e75 (27.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e29 (33.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are given as mean \u0026plusmn; standard deviation, number (percentage), or median (range).\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003cem\u003eP\u003c/em\u003e \u0026lt; .05 was considered statistically significant.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e* Kruskal-Walis test\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e# Pearson\u0026rsquo;s chi-squared test\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eComparisons of patient outcomes\u003c/h2\u003e \u003cp\u003eIn the balloon group, all patients successfully underwent occlusion balloon placement before delivery, and all balloons were well inflated following cesarean section. The median time taken for attempted femoral artery cannulation was 130 s (range, 75\u0026ndash;1265 s). The mean (SD) fluoroscopy time range was 2.8 [1.3] s (range, 1.4\u0026ndash;5.6 s). The mean estimated maternal radiation exposure was 2.3 [1.0] (range, 1.2\u0026ndash;4.6) mGy, which is considered safe in pregnancy.[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eMean (SD) estimated blood loss during surgery were 1370.5.4 [752.0] ml and 3536.8 [1383.2] ml in the balloon and reference groups, respectively (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA). Accordingly, fewer units of packed red blood cells were transfused in the balloon group than in the reference group (3.0 [4.0] vs. 13.8 [6.9], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). There were 264/278 (95.0%) and 23/86 (26.7%) patients preserving their uterus successfully in the balloon and reference groups, respectively (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC). The mean (SD) operation duration in the balloon group was significantly shorter than that in the reference group (96.3 [37.6] min vs. 160.6 [45.5] min) (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eD). Patients in the balloon group had a lower ICU admission rate (168/278, 60.4%) than did their counterparts in the reference group (67/86, 77.9%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.003) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE). The NICU admission rate showed no significant difference between the groups (176/278 (63.3%) vs 52/86 (60.4%), \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;.70) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eF). No difference in mean (SD) total maternal medical costs was found between the groups (\u003cspan\u003e$\u003c/span\u003e4925.4 [1740.7] vs \u003cspan\u003e$\u003c/span\u003e5083.2 [1705.1], \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.13) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eG).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eSurgery-related and catheterization-related complications\u003c/h2\u003e \u003cp\u003eThere was no sepsis, peritonitis, fistula, acute pulmonary edema, acute renal failure, pulmonary embolism, or death in either group. For other severe morbidities, including reoperations (repeat laparotomy to perform hysterectomy or hemostasis, abdominal wall hematoma removal, uterine artery embolization, and thromboembolectomy) and thromboembolic events (deep vein thrombosis and arterial thrombosis), bowel or urinary tract injury also presented no differences between groups (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eH). A summary of the explicit severe maternal morbidities is provided in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. In the balloon group, four of eight patients who had femoral arterial thrombosis underwent thromboembolectomy. The remaining four patients were successfully managed with thrombolytic therapy. It is clear the frequency of thrombolysis and thromboembolectomy have a marked increase with the balloon procedures.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCases of severe maternal morbidity in reference and balloon group\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReoperations\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eThromboembolic events\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eInjury to adjacent organs\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTotal (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReference group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAbdominal wall hematoma removal \u0026sdot; 3\u003c/p\u003e \u003cp\u003elaparotomy with hysterectomy \u0026sdot; 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDeep vein thrombosis \u0026sdot; 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBowel injury \u0026sdot; 1\u003c/p\u003e \u003cp\u003eUrinary tract injury \u0026sdot; 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e14.0 (12/86)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBalloon group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAbdominal wall hematoma removal \u0026sdot; 3\u003c/p\u003e \u003cp\u003elaparotomy with hysterectomy \u0026sdot; 3\u003c/p\u003e \u003cp\u003eThromboembolectomy \u0026sdot; 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDeep vein thrombosis \u0026sdot; 7\u003c/p\u003e \u003cp\u003eArterial thrombosis \u0026sdot; 8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eUrinary tract injury \u0026sdot; 11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12.9 (36/278)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn the balloon group, the mean (SD) occlusion time was 14.6 [8.3] (range, 5\u0026ndash;54) min. Overall, 7.19% (20/278) of the patients experienced interventional radiology-related complications. Of the 278 patients, regular uterine contractions after the intervention was detected in 12 (4.32%), local catheter-related infections in two (0.72%), local hemorrhage in three (1.08%), and hematomas in three (1.08%) patients.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eRisk factors for thrombosis\u003c/h2\u003e \u003cp\u003eFrom the perspective of clinical expertise, we selected aortic occlusion time, estimated blood loss, operation duration, femoral artery cannulation time, and indwelling sheath duration as predictable variables that may be connected with femoral arterial thrombosis. On the univariate logistic regression analysis (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), none of these characteristics were associated with an increased thrombotic risk at the femoral site.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePredictors of thrombotic risk in the femoral location in the balloon group\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eFemoral arterial thrombosis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eUnadjusted OR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYes, \u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;8\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo, \u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;270\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAortic occlusion time (m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 (10\u0026ndash;30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12 (5\u0026ndash;54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.06 (0.95\u0026ndash;1.18)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.30*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEstimated blood loss (ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1200 (500\u0026ndash;3500)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1000 (400\u0026ndash;5000)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.99 (0.98\u0026ndash;1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.09*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOperation duration (m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68 (60\u0026ndash;235)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90 (42\u0026ndash;285)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.01 (0.98\u0026ndash;1.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.59*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemoral artery cannulation time (s)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e140 (90\u0026ndash;775)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e130 (75\u0026ndash;1265)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.98 (0.95\u0026ndash;1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.21*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIndwelling sheath duration(h)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.5 (4.0\u0026ndash;26.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.5 (4.5\u0026ndash;30.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.99 (0.95\u0026ndash;1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.60*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eObstetric hemorrhage is the principal cause of maternal morbidity and mortality worldwide [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. AIP is one of the most likely obstetrical factors that cause massive postpartum hemorrhage. Therefore, managing AIP by effectively reducing blood loss and associated maternal morbidity and mortality rates is essential.\u003c/p\u003e \u003cp\u003eAlthough ultrasonography combined with MRI has shown satisfactory sensitivity and specificity in the prenatal diagnosis of AIP [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], we excluded three patients whose intraoperative findings were incompatible with the prenatal findings. The balloon was not inflated during the operation in these three patients. From this point, the balloon was prophylactically placed, rather than prophylactically inflated, in patients with the highest suspicion of AIP to avoid unnecessary risks associated with aortic occlusion because of false-positive prenatal diagnoses.\u003c/p\u003e \u003cp\u003eUnlike REBOA used in trauma and emergency medicine, prophylactic placement of endovascular balloon occlusion catheter can be a fundamental component of the surgical AIP management. Indeed, REBOA can be deployed in pregnant women with established hemorrhagic shock during an emergency peripartum hysterectomy as a rescue maneuver to maintain the stability of the circulatory system [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo this day, the safety and efficacy of REBOA in women with a prenatal diagnosis of AIP are yet to be confirmed[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Published results have been conflicting, ranging from affirmative [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] to skeptical [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] to inconclusive [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. However, most studies involved small numbers of patients or did not distinguish abnormal adherent placenta (known as creta) from AIP (known as increta and percreta), despite the latter two conditions being the main causes of massive obstetric hemorrhage and infertility[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Given the lack of effective hemostasis, even handled by an experienced multidisciplinary team of surgeons, peripartum hysterectomy presented considerable risks because of possible pelvic adhesions attributed to previous surgery, enlarged blood supply to the pregnant uterus, and possible invasion to the parametrium in cases of placenta percreta. Therefore, morbidities and mortality associated with surgery for AIP are significant, and perioperative complications are common [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. REBOA provides time and opportunity for surgeons to perform surgical deliberately, reduce the complexity of the operation, and eventually lower the technical challenge to manage AIP. We did not find significant differences in rates of urinary tract or bowel injury between the groups. This may be due to the fact that all patients were managed by an experienced multidisciplinary care team and each group has small number of cases with complications.\u003c/p\u003e \u003cp\u003eREBOA deployment-related complications are another concern, including those related to femoral artery cannulation, balloon positioning and removal, and thromboembolic events. Excluding other mild complications, arterial thrombosis is one of the most common severe complications of REBOA, with a reported incidence of 5% [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Lower limb ischemia, pseudo-aneurysm formation, ischemic femoral nerve injury, and maternal death due to abdominal aortic dissection have been reported [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Obstetric hemorrhage offers expanding indications for REBOA, and the exact incidence and predictors of each complication remain unclear. In this study, there were 8/278 (2.88%) cases of arterial thrombosis in the balloon group, but no vascular injuries or lower limb ischemic episodes. It appears that percutaneous cannulation disrupts the integrity of the vessel wall, triggering thrombus formation. Women generally have small-caliber arteries, a fact that is independently associated with arterial obstruction [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], and pregnancy itself is a risk factor for hypercoagulability. These patients may be more vulnerable to thrombosis because of the administration of tranexamic acid or other coagulation factors. To determine risk factors for arterial thrombosis, univariate logistic regression analysis was implemented; however, no relative variables were found, despite some studies having reported longer catheter dwell times, prolonged femoral artery cannulation times, and multiple punctures for catheter insertion to be associated with thrombosis or embolism [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. The small number of arterial thrombosis cases may be a reason; therefore, multicenter prospective studies are needed to confirm predictors of thrombotic risk of REBOA in obstetrics. Although long occlusion time (4\u0026ndash;6 h) of the infrarenal aorta is possible [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], our strategy is intermittent deflation of the balloon to relieve organic ischemia and removing the catheter and sheath as soon as possible while the vital signs remain stable. As anticipated, common femoral artery cannulation performed by skilled hands and smaller introducer sheaths for REBOA may be associated with fewer access-related complications [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eConsidering REBOA-related complications, most findings generated from their application in trauma patients with hemorrhagic shock. Although the small number of cases in our study makes it unfeasible to draw definite conclusions, the patients should be informed of the higher risk for arterial thrombosis. Moreover, AIP patients should be counseled on the increased likelihood of recurrence in subsequent pregnancies before choosing conservative treatment, for the recurrence among women with PAS who retained their uterus is 13.3\u0026ndash;29.6% [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. The next step should be to identify associated risk factors and define REBOA inclusion criteria to identify the subgroups of AIP patients who gain more benefits from REBOA.\u003c/p\u003e \u003cp\u003eIn this study, 14 patients in the balloon group failed to retain their uteri. Even with the support of REBOA, it remains challenging to prejudge the chances of preserving the uterus successfully at the point when the peritoneum is opened. REBOA-assisted cesarean section remains a novel method for AIP patients, and the intraoperative strategy and patient outcomes also need to be improved over time.\u003c/p\u003e \u003cp\u003eIncluding expenditures related to vascular and interventional radiology processes, the total medical costs in the balloon group showed no significant difference with those in the reference group. Undoubtedly, the decreased requirement for blood product lowered the total costs of medical care. Lower need for blood transfusion and ICU admission in the balloon group means that REBOA is particularly suitable for regions where blood products are relatively restrained.\u003c/p\u003e \u003cp\u003eAn alternative interventional radiologic modality used in women with PAS is occlusion of the internal iliac arteries. Nevertheless, this process appears to be more debatable regarding its benefits in terms of hemostasis than the benefits associated with aortic occlusion [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. This is most likely explained by the extensive collateral blood supply of the pelvis. Randomized controlled studies are needed to examine the risks and benefits of REBOA compared with those of internal iliac artery occlusion. What is certain is that REBOA only requires cannulation of a single common femoral artery, and the exposure dose to the fetus is considered lower and is, therefore, acceptable [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study has some limitations. This study has single-center and retrospective design. Moreover, follow-up data on future pregnancies following this intervention is still not available. Without knowledge of how these patients do in future pregnancies, the role of REBOA in the preservation of fertility in AIP patients still cannot be revealed. In addition, skills of the REBOA operator were not evaluated. A future multicenter prospective study is needed to expand on this innovative approach. Finally, the cost-effectiveness analysis is likely only applicable to China. Other health care systems may or may not see a benefit.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study demonstrated that REBOA, as an adjunct therapeutic strategy for hemostasis, can help to reduce intraoperative blood loss and salvage the uterus in AIP patients.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAIP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eabnormally invasive placenta\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePAS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eplacenta accreta spectrum\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eREBOA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eresuscitative endovascular balloon occlusion of the aorta\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eICU\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eintensive care unit\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eNICU\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eneonatal intensive care unit\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003emagnetic resonance imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCI, confidence interval\u003c/div\u003e \u003cdiv class=\"Description\"\u003e\u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOR, odds ratio.\u003c/div\u003e \u003cdiv class=\"Description\"\u003e\u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe are deeply grateful to the medical staff at the Obstetrics and Gynecology Department of The Affiliated Hospital of Qingdao University, Qingdao, China. We want to thank all the patients who participated in this study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYY, JL, and JZ were involved in the conception and design of the study. YY, JL, WP, SL, and JZ were involved in the planning of the study. YY, JL, WP, SL, YZ, CY and YW were involved in data collection and carrying out of the study. SL, YZ, CY, CL, and YW were involved in the analysis of the project. YY, JL, and JZ primarily wrote the manuscript, with editing contributions from all authors.\u0026nbsp;All the authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the Natural Science Foundation of Shandong Province under Grant ZR2019MH127. The funders of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article and its supplementary information files.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEthical approval and consent to participate\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll methods were performed in accordance with the relevant guidelines and regulations. This study was approved by the local ethics committee of the Affiliated Hospital of Qingdao University(protocol number: QYFY WZLL 25523 on April 19, 2015), which waived the need for written informed consent given the retrospective nature of the study and the use of anonymized data from hospital records.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors report no conflict of interest.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eJauniaux E, Collins S, Burton GJ: \u003cb\u003ePlacenta accreta spectrum: pathophysiology and evidence-based anatomy for prenatal ultrasound imaging\u003c/b\u003e. 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Am J Obstet Gynecol 2019.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee AY, Ballah D, Moreno I, Dong PR, Cochran R, Picel A, Lee EW, Moriarty J, Padgett M, Nelson K \u003cem\u003eet al\u003c/em\u003e: \u003cb\u003eOutcomes of balloon occlusion in the University of California Morbidly Adherent Placenta Registry\u003c/b\u003e. 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Obstet Gynecol 2015, \u003cb\u003e126\u003c/b\u003e(5):1022\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAllen L, Jauniaux E, Hobson S, Papillon-Smith J, Belfort MA, Diagnosis FPA, Management Expert Consensus P: \u003cb\u003eFIGO consensus guidelines on placenta accreta spectrum disorders: Nonconservative surgical management\u003c/b\u003e. Int J Gynaecol Obstet 2018, \u003cb\u003e140\u003c/b\u003e(3):281\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBolnga JW, Mola GDL, Ao P, Sapau W, Verave O, Lufele E, Laman M: \u003cb\u003eMortality and morbidity after emergency peripartum hysterectomy in a provincial referral hospital in Papua New Guinea: A seven-year audit\u003c/b\u003e. Aust N Z J Obstet Gynaecol 2021, \u003cb\u003e61\u003c/b\u003e(3):360\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDilauro MD, Dason S, Athreya S: \u003cb\u003eProphylactic balloon occlusion of internal iliac arteries in women with placenta accreta: literature review and analysis\u003c/b\u003e. Clin Radiol 2012, \u003cb\u003e67\u003c/b\u003e(6):515\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaito N, Matsumoto H, Yagi T, Hara Y, Hayashida K, Motomura T, Mashiko K, Iida H, Yokota H, Wagatsuma Y: \u003cb\u003eEvaluation of the safety and feasibility of resuscitative endovascular balloon occlusion of the aorta\u003c/b\u003e. J Trauma Acute Care Surg 2015, \u003cb\u003e78\u003c/b\u003e(5):897\u0026ndash;903; discussion 4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBedford RFJA: \u003cb\u003eRadial arterial function following percutaneous cannulation with 18-and 20-gauge catheters\u003c/b\u003e. 1977, \u003cb\u003e47\u003c/b\u003e(1):37\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNieto-Calvache AJ, Hidalgo-Cardona A, Lopez-Giron MC, Rodriguez F, Ordonez C, Garcia AF, Mejia M, Pabon-Parra MG, Burgos-Luna JM: \u003cb\u003eArterial thrombosis after REBOA use in placenta accreta spectrum: a case series\u003c/b\u003e. J Matern-Fetal Neo M 2020.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrenner M, Bulger EM, Perina DG, Henry S, Kang CS, Rotondo MF, Chang MC, Weireter LJ, Coburn M, Winchell RJ \u003cem\u003eet al\u003c/em\u003e: \u003cb\u003eJoint statement from the American College of Surgeons Committee on Trauma (ACS COT) and the American College of Emergency Physicians (ACEP) regarding the clinical use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA)\u003c/b\u003e. Trauma Surg Acute Care Open 2018, \u003cb\u003e3\u003c/b\u003e(1):e000154.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRomagnoli A, Teeter W, Pasley J, Hu P, Hoehn M, Stein D, Scalea T, Brenner M: \u003cb\u003eTime to aortic occlusion: It's all about access\u003c/b\u003e. J Trauma Acute Care 2017, \u003cb\u003e83\u003c/b\u003e(6):1161\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMullen C, Battarbee AN, Ernst LM, Peaceman AM: \u003cb\u003eOccult Placenta Accreta: Risk Factors, Adverse Obstetrical Outcomes, and Recurrence in Subsequent Pregnancies\u003c/b\u003e. Am J Perinatol 2019, \u003cb\u003e36\u003c/b\u003e(5):472\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBaldwin HJ, Nippita TA, Torvaldsen S, Ibiebele I, Ford JB, Patterson JA: \u003cb\u003eOutcomes of Subsequent Births After Placenta Accreta Spectrum\u003c/b\u003e. Obstet Gynecol 2020, \u003cb\u003e136\u003c/b\u003e(4):745\u0026ndash;55.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAngileri SA, Mailli L, Raspanti C, Ierardi AM, Carrafiello G, Belli AM: \u003cb\u003eProphylactic occlusion balloon placement in internal iliac arteries for the prevention of postpartum haemorrhage due to morbidly adherent placenta: short term outcomes\u003c/b\u003e. Radiol Med 2017, \u003cb\u003e122\u003c/b\u003e(10):798\u0026ndash;806.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYu SCH, Cheng YKY, Tse WT, Sahota DS, Chung MY, Wong SSM, Chan OK, Leung TY: \u003cb\u003ePerioperative prophylactic internal iliac artery balloon occlusion in the prevention of postpartum hemorrhage in placenta previa: a randomized controlled trial\u003c/b\u003e. Am J Obstet Gynecol 2020, \u003cb\u003e223\u003c/b\u003e(1):117 e1- e13.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Cesarean hysterectomy, Obstetric hemorrhage, Placenta accreta spectrum, Abnormally invasive placenta, REBOA","lastPublishedDoi":"10.21203/rs.3.rs-1773482/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1773482/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003ePatients with abnormally invasive placenta (AIP) are at high risk of massive postpartum hemorrhage. Resuscitative endovascular balloon occlusion of the aorta (REBOA) as an adjunct therapeutic strategy for hemostasis offers the obstetrician an alternative for the treatment of patients with abnormally invasive placenta. This study aimed to evaluate the role of REBOA for hemorrhage control in patients with AIP. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This is a historical cohort study with prospectively collected data at a single tertiary center between January 2014 to July 2021. In\u003cstrong\u003e \u003c/strong\u003etotal, 364\u003cstrong\u003e \u003c/strong\u003esingleton pregnant AIP patients with desire to preserve uterus and delivered were separated into two groups. The study group (balloon group, n=278) underwent REBOA during cesarean section, whereas the reference group (n=86) did not undergo REBOA. Surgical details and maternal outcomes were collected. The primary outcome was estimated blood loss and the rate of uterine preservation. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e A total of 278 [76.4%] participants experienced REBOA during cesarean section. Patients in the balloon group had less mean (SD) blood loss during cesarean section (1370.5 [752.0] ml vs. 3536.8 [1383.2] ml; \u003cem\u003eP\u003c/em\u003e\u0026lt;.001) and had their uterus salvaged more often (264 [95.0%] vs. 23 [26.7%]; \u003cem\u003eP\u003c/em\u003e\u0026lt;.001). These patients were also less likely to be admitted to the intensive care unit after delivery (168 [60.4%] vs. 67 [77.9%]; \u003cem\u003eP\u003c/em\u003e=.003) and had less mean (SD) operating time (96.3 [37.6] min vs. 160.6 [45.5] min; \u003cem\u003eP\u003c/em\u003e\u0026lt;.001). The rate of neonatal intensive care unit admission (176 [63.3%] vs. 52 [60.4%]; \u003cem\u003eP\u003c/em\u003e=.70) and total mean (SD) maternal medical costs ($4925.4 [1740.7] vs. $5083.2 [1705.1]; \u003cem\u003eP\u003c/em\u003e=0.13) did not differ between the groups.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eAs a robust hemorrhage-control technique, REBOA can reduce intraoperative hemorrhage in patients with AIP. The next step is to identify associated risk factors and define REBOA inclusion criteria to identify the subgroups of AIP patients who may gain more benefits.\u003c/p\u003e","manuscriptTitle":"Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-07-25 14:26:54","doi":"10.21203/rs.3.rs-1773482/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2022-09-05T11:05:10+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-08-31T12:25:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"6765ba16-1cd3-4d83-b154-e091f999c3be_SNPRID","date":"2022-08-20T09:55:50+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-08-18T22:46:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"051fc671-69e4-4342-bd4a-c98fa889d224","date":"2022-08-07T03:48:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"a934295e-7d63-457e-9d47-a541c41c754e","date":"2022-08-07T01:07:23+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-08-03T22:37:02+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-07-27T12:32:32+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2022-07-23T14:32:02+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-07-23T14:25:20+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pregnancy and Childbirth","date":"2022-06-19T12:15:40+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"236cebc1-b04e-4386-84cc-c1d82f6c4b44","owner":[],"postedDate":"July 25th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-10-16T20:53:46+00:00","versionOfRecord":{"articleIdentity":"rs-1773482","link":"https://doi.org/10.1186/s12884-023-05649-8","journal":{"identity":"bmc-pregnancy-and-childbirth","isVorOnly":false,"title":"BMC Pregnancy and Childbirth"},"publishedOn":"2023-05-10 20:46:30","publishedOnDateReadable":"May 10th, 2023"},"versionCreatedAt":"2022-07-25 14:26:54","video":"","vorDoi":"10.1186/s12884-023-05649-8","vorDoiUrl":"https://doi.org/10.1186/s12884-023-05649-8","workflowStages":[]},"version":"v1","identity":"rs-1773482","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1773482","identity":"rs-1773482","version":["v1"]},"buildId":"zQwnuV7TCBrMSSSToR1PI","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}