Association between routine Cell Salvage use for Lower Segment Caesarean Section and post-operative iron infusion and hemoglobin during the Covid-19 Pandemic

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Prior to April 2020, we initiated intraoperative cell salvage during caesarean section based on risk assessment for hemorrhage and patient factors. As the pandemic broadened, we mandated intraoperative cell salvage to prevent peri-partum anemia and potentially reduce blood product usage. We examined the association of routine intraoperative cell salvage on maternal outcomes. Methods We conducted a single-center non-overlapping before-after study of obstetric patients undergoing lower segment caesarean section in the 2 months prior to change in practice (‘usual care = selective intraoperative cell salvage’, n = 203) and the 2 months following (‘mandated intraoperative cell salvage’, n = 228). Recovered blood was processed when a minimal autologous reinfusion volume of 100 ml was expected. Post-operative iron infusion and length of stay were modelled using logistic or linear regression, using inverse probability weighting to account for confounding. Results More emergency lower segment caesarean sections occurred in the Usual Care group. Compared to the Usual Care group, post-operative hemoglobin was higher and anemia cases fewer in the Mandated intraoperative cell salvage group. Rates of post-partum iron infusion were significantly lower in the Mandated intraoperative cell salvage group (OR = 0.31, 95% CI = 0.12 to 0.80, P = 0.016). No difference was found for length of stay. Conclusion Routine cell salvage provision during lower segment caesarean section was associated with a significant reduction in post-partum iron infusions, increased post-operative hemoglobin and reduced anemia prevalence. Figures Figure 1 take-home message Cell salvage provision during cesarean section is a valuable tool and reduces the incidence of post-partum anemia and the need for post-partum iron infusion. It may contribute to an avoidance or reduction of allogeneic red blood cell transfusion in the peri-partum setting. Introduction In March 2020, the World Health Organization (WHO) declared a pandemic status for the coronavirus disease 2019 (COVID-19). In addition to the unprecedented pressures on health care systems, COVID-19 has had a profound impact on the number of blood donations, leaving blood services severely challenged to maintain their inventory during the pandemic.[ 1 – 3 ] These challenges highlight the critical importance for Patient Blood Management (PBM) as an integral part of patient care. In a recent publication a multinational and diverse group of authors issued a “Call to Action” urging all stakeholders and providers to implement practical and multimodal principles of PBM.[ 4 ] PBM is a patient-centered approach, applying an evidence-based bundle of care to preserve the patient’s own blood by managing anemia, minimizing iatrogenic blood loss, and harnessing tolerance to anemia to improve patient outcome.[ 5 ] Intraoperative cell salvage (IOCS) is an integral and valuable component of PBM.[ 6 , 5 , 7 ] The benefits from IOCS have been known for some time.[ 8 ] Clinical adoption of IOCS in obstetrics for lower segment caesarean section (LSCS) has increased substantially, but despite this, the utilization of this technique varies considerably around the world.[ 9 – 11 ] At our institution, IOCS has been an established modality since 2013, as part of our hospital-wide PBM approach. Prior to April 2020, our institutional practice included initiation of IOCS during LSCS based on pre-operative anemia, patient risk assessment for intra-operative blood loss, post-partum hemorrhage and other individual patient factors. In response to the Australian National Blood Authority’s call to adhere to PBM guidelines and practices during the pandemic, in order to preserve finite reserves of donated blood, [ 12 ] [ 13 ]members of the Departments of Anesthesia and Obstetrics at our institution discussed if modifications of our PBM practices were warranted to prevent the incidence and severity of peri-partum anemia. A decision was made to trial the mandated use of IOCS for all LSCS during the height of the first wave of the pandemic, to explore whether this practice could reduce the need for red blood cell (RBC) transfusion. We also aimed to examine the association of routine IOCS for LSCS on other indicators of optimal PBM, including the rate and volume of returned cell salvaged blood and the incidence and degree of post-partum anemia, as well as the impact on other maternal outcomes such as length of hospital stay. Methods This study was approved by our Institutional Review Board (IRB), (CALHN Reference Number: 14994). Written informed consent was waived by the IRB. We conducted a single-center non-overlapping before-after study of all obstetric patients undergoing either elective or emergent lower segment caesarean section over a four-month period in early 2020. Exclusion criteria were caesarean section for stillbirth or patient refusal of the utilization of cell salvage, which was discussed while obtaining anesthesia consent. This study adheres to The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement.[ 14 ] Data from selective intra-operative cell salvage practice (06 February 2020–05 April 2020) and the subsequent two months (06 April 2020-05 June 2020) with use of routine intra-operative shed blood collection was collected from electronic and paper records, after the completion of the study period. Participants were identified via electronic hospital records, using the search terms “LSCS” and “Caesarean” between the above dates. Anemia was defined as hemoglobin (Hb) < 110 g/L during pregnancy and Hb < 100 g/L post-partum.[ 13 ] The risk of bias was low, as for both groups, the recovered blood was processed when a substantial blood loss occurred, and the autologous RBC reinfusion volume was expected to reach 100 ml or more. Statistical Analysis Descriptive statistics summarized patient characteristics using counts and percentages for categorical data, means and standard deviations or medians and interquartile ranges for continuous data, as appropriate. To compare post-operative outcomes between the groups who were mandated IOCS or received usual care, t-tests for normally distributed continuous data, Kruskal-Wallis tests for skewed data, and chi-square tests for categorical data were used. Post-partum iron infusion was modelled using logistic regression, and log-transformed length of stay with linear regression. Other outcomes, such as post-operative hemoglobin or anemia, were not modelled due to a large proportion of missing data. Differences between mandated IOCS and usual care were expressed as odds ratios for post-partum iron infusion and geometric mean ratios for length of stay, and 95% confidence intervals (CI). To account for potential confounding by differences in patients between time periods and type of care, a counterfactual approach with propensity modelling was used. The propensity model used mandated IOCS vs usual care as the outcome with covariates age, parity, gravida, ASA score, pre-operative Hb, operation type and anesthesia type. The propensity model was used to create trimmed, stabilized inverse probability weights (IPW). Standardized mean differences (SMD) were used to assess balance in covariates at baseline before and after weighting, where an SMD > 0.1 was considered imbalanced. Finally, to investigate the possibility that the changes over time could have occurred regardless of mandated IOCS, an interrupted time series (ITS) analysis, adapted for short time periods, was performed using the R package ‘its.analysis’. Post-partum IV iron and length of stay were aggregated by week to create time series. A significant difference in the outcome between the two periods was tested, accounting for important covariates and autocorrelation in the outcome over time. The ITS model for number of post-operative iron infusions per week used pre-operative anemia, operation type and primiparity as covariates, while the model for log-transformed length of stay included pre-operative Hb, emergency operation and primiparity rates. Statistical significance was assessed at the p = 0.025 level to account for two outcomes. R statistical software version 4.1.0 (R Foundation for statistical computing, Vienna Austria) was used for all statistical analyses. Results A total of 431 participants were included in the study. During the first two months, 203 women underwent caesarean section delivery and received usual care, while 228 women delivered during the period where IOCS was mandated for caesarean deliveries. Before inverse probability weighting, 6/9 pre-partum maternal characteristics were unbalanced with SMD > 0.1 (Table 1 ). After weighting, the imbalance was removed (all SMD < 0.1). Table 1 Maternal demographic and obstetric data in two cohorts during periods of usual care or where intraoperative cell salvage (IOCS) was mandated for caesarean section deliveries. Mandated IOCS n = 228 Usual Care n = 203 Unweighted SMD Weighted SMD Age, mean (SD) 31 (5) 30 (6) 0.178 0.001 Gravida, median (IQR) 2.5 (1–3) 2 (1–3) 0.118 0.027 Parity, median (IQR) 1 (0–2) 1 (0–2) 0.004 0.003 Caesarean Section, n (%) Elective Emergency 120 (53%) 108 (47%) 86 (42%) 117 (58%) 0.207 0.016 ASA score, n (%) 1 2 3 4 64 (28%) 159 (70%) 5 (2%) 0 (0%) 57 (28%) 141 (70%) 4 (2%) 1 (1%) 0.101 0.069 Anesthesia Spinal Epidural Gen. Anesthesia (GA) CSE Combination^ ^Combinations included: Spinal + GA Epidural + GA Epidural + Spinal + GA 161 (71%) 42 (18%) 14 (6%) 5 (2) 6 (3%) 2 (1%) 4 (2%) 0 128 (63%) 55 (27%) 14 (7%) 2 (1%) 4 (2%) 0 3 (2%) 1 (1%) 0.204 0.006 Pre-operative Hb (g/L), mean (SD) 125 (12) 124 (13) 0.120 0.030 Pre-operative Anemia, n (%) 25 (11%) 24 (12%) 0.024 0.075 Pre-operative IV iron, n (%) 6 (3%) 22 (11%) 0.068 0.043 There was no difference in allogeneic RBC transfusion, with only one woman in each group receiving blood products. Univariate analysis showed that post-operatively, women in the Mandated IOCS group had higher post-operative Hb values, 111 g/L vs 102 g/L (p < 0.001) (despite similar pre-operative Hb, 125 g/L vs 124 g/L), had significantly lower rates of anemia, 48% vs 78% (p < 0.001) and less often exposed to post-partum intravenous iron, 11% vs 3% (p < 0.001) (Table 2 ). A higher proportion of women in the Usual Care cohort had an emergency caesarean section (p = 0.03), greater estimated blood loss (EBL) (p = 0.003). Table 2 Post-operative Hb and anemia status of women according to use of mandated intraoperative cell salvage (IOCS). IOCS mandated n = 228 Usual care n = 203 p Cell Salvage deployed, n (%) n = 227 196 (86%) n = 203 62 (31%) < 0.001 Post-operative Hb (g/L), mean (SD) Anemia, n (%) n = 71 111 (14) 14 (20%) n = 95 102 (12) 39 (41%) < 0.001 0.004 Received post-operative IV iron, n (%) 24 (11%) 26 (13%) 0.46 Estimated blood loss (ml), median (IQR) 400 (300–600) 500 (350–700) 0.003 Blood reinfused, n (%) 21 (9%) 6 (3%) 0.008 Reinfusion volume (ml), med (IQR) n = 21 250 (134–338) n = 6 284 (245–290) 0.86 Statistical modelling showed that women who were mandated IOCS had lower rates of post-partum iron infusion (odds ratio (OR) = 0.31, 95% CI = 0.12 to 0.80, P = 0.016) than women in the Usual Care group (Table 3 ). After weighting, length of stay was not different between the groups (geometric mean ratio = 0.93, 95% CI = 0.86 to 1.004, p = 0.063). These results were confirmed by the ITS analysis (P = 0.012 and P = 0.23 for post-partum iron and length of stay, respectively). Figure 1 shows average weekly cell salvage and post-partum iron rates and length stay before and after mandated IOCS. Table 3 Multivariable statistical modelling with and without inverse probability weighting and interrupted time series (ITS) p-value for a difference between time periods. Outcome Unweighted Estimate (95% CI) Unweighted P-value Weighted Estimate (95% CI) Weighted P-value ITS P-value Post-partum IV iron 1 0.22 (0.09–0.56) 0.001 0.31 (0.12–0.80) 0.016 0.012 Length of Stay 2 0.90 (0.84–0.97) 0.006 0.93 (0.86–1.004) 0.063 0.23 1 Odds ratio for Yes vs No for mandated intraoperative cell salvage vs Usual Care 2 Geometric mean ratio for mandated intraoperative cell salvage vs Usual Care Discussion The introduction of routine IOCS for caesarean deliveries during the early phase of the COVID-19 pandemic resulted in higher processing rates and reinfusion volumes of autologous RBC. Consequently, post-partum Hb values were improved and anemia less prevalent in women from this cohort. Intravenous iron prescription occurred less often after delivery, and there was no difference in allogeneic RBC transfusion rates between the two groups. These finding add to the existing evidence demonstrating the safety and efficacy of autologous salvaged blood in the context of LSCS, through conservation of patient blood and maintained iron stores. After accounting for difference between patients at baseline, mandating cell salvage reduced post-operative iron infusion rates. Length of stay however, appeared to be in decline prior to the COVID restrictions and there was no significant difference between the time periods. Although not contradicted in this study, IOCS has been shown to reduce the need for allogeneic transfusion of RBC in other surgical settings.[ 6 , 15 ] In 2012, Liumbruno et al labelled IOCS “the most practical, effective and useful blood conservation technique in obstetrics”.[ 15 ] Due to comprehensive staff education and general enthusiasm for the implementation for PBM among staff across disciplines at our hospital, IOCS was introduced in 2013 for elective and emergency surgery. It quickly became an essential tool of managing maternal bleeding, combined with a specific obstetric hemorrhage bleeding protocol and point-of-care coagulation monitoring. This comprehensive obstetric PBM approach resulted in the lowest RBC transfusion rate in South Australia (personal communication, South Australian Blood, Organ and Tissue Programs). The trial period of mandated IOCS in response to the limited blood availability during COVID-19 pandemic, demonstrated no further reduction in RBC transfusion rate. It was however, associated with an improvement in Hb status and reduced rates of post-partum iron deficiency anemia in the Mandated IOCS group compared to those receiving Usual Care. These outcomes may explain the 69% four-month trial period highlight the benefits for the patient derived from utilization of IOCS for LSCS. This study has highlighted the valuable contribution of IOCS in obstetric patient care. The mandated use of IOCS enhanced the effectiveness of an established and successful PBM approach, adding to the pre-existing strong body of evidence. Over the last decade the outcomes for over 2000 cases of autologous RBC re-infusion after red blood cell recovery during LSCS have been published in the literature. This research has demonstrated the safety, efficacy, and benefits of IOCS, [ 6 , 9 , 10 , 16 , 11 , 17 ] regardless of technique, for example differing suction set ups, the use or absence of leucocyte depletion filters, and selective versus routine cell salvage provision. Maternal mortality is increasing in the United States and many parts of the world.[ 10 ] Obstetric hemorrhage is the most common cause for maternal death and consequently peri-partum RBC transfusion rates are on the rise, accounting for approximately 3% of all RBC transfusions.[ 18 ] It is important to emphasize that these transfusion events occur in young women, who potentially suffer long-term consequences from the exposure to allogeneic RBC’s.[ 19 , 20 ] Bleeding during child birth can be life-threatening and is notoriously difficult to predict.[ 21 ] IOCS in obstetrics is recommended by organizations such as The Association of Anaesthetists of Great Britain and Ireland, The National Institute for Health and Clinical Excellence, The American College of Obstetrics & Gynaecology, The Australian National Blood Authority, the Network for the Advancement of Patient Blood Management, Haemostasis and Thrombosis and the German/Austrian/Swiss Societies of Gynecology and Obstetrics (DGGG, OEGGG, SGGG).[ 22 – 27 ] However, the availability of this important tool is far from universal and often absent, even in many large obstetric services. In a recent publication, Hofmann et al screened international efforts and strategies to identify the four main drivers for successful PBM implementation: patient outcomes, cost savings, preventing blood shortages and patient safety.[ 28 ] Whether routine IOCS in obstetrics is cost saving remains unclear, the use of red cell recovery and autotransfusion clearly supports improved patients outcomes, improved patient safety and prevention of blood shortages, all of which have been urgently required during the COVID-19 pandemic.[ 4 , 29 ] Withholding the provision of IOCS in obstetrics deprives women of the safest form of RBC transfusion, exposing them to preventable anemia and the well-known risks of allogeneic transfusion. Clinicians from around the world caring for women during childbirth should strengthen their efforts to establish IOCS as an integrated modality on a much broader scale.[ 30 – 32 ] Limitations The two-month trial of mandated IOCS at our site limited the number of patients included in this study. While we did observe higher rates of re-infusion in the mandated group, a much larger sample size would be required to detect any difference in the donor blood transfusion rates. This sample size would depend on the baseline rate of transfusion, which is already low at our site given our established PBM program. Nonetheless, the benefits of IOCS were still apparent, including lower rates of iron-deficient anemia, a higher post-operative Hb. In the Usual Care group, cell salvage was initiated for 31% (n = 62/203) women while 86% of women (n = 196/227) had cell salvage initiated following the mandate. The uptake of cell salvage following the introduction of the mandate started at 48% in week 1, increasing to 93% in week 2. It then remained high throughout the two-month period, ranging from 75–96%. Reasons for IOCS not being used include some staff being unaware of new trial clinical protocol and clinician preference. Interestingly in this study, the EBL was lower in the IOCS Mandate group compared to the Usual Care group. Multiple factors may have contributed to this finding, including the higher number of emergency caesarean sections in the Usual Care IOCS group. In addition, the single cell salvage set-up may have limited observation of any blood loss, which is already notoriously inaccurate as it relied on visual assessment. Due to a functional PBM program at our hospital, cell salvage was already occurring in the routine care group, before it was mandated. This represents confounding and may reduce the significance of our observed results. However, it was not the purpose of the study to test cell salvage vs no cell salvage. The authors acknowledge that while statistically significant results were observed, the clinical significance of this is less certain. We also acknowledge that a study with a significantly larger sample size is required to observe differences in donor transfusion rates and indeed overall cost effectiveness of mandated IOCS. Conclusions Routine cell salvage provision during LSCS associated with an increased post-operative hemoglobin and reduced anemia incidence which may contribute to an avoidance of limited blood products. We also observed a reduction in post-partum iron infusions. Currently, there are a number of barriers to the routine use of IOCS at some sites, including a lack of awareness and funding to support IOCS establishment and protocols for routine IOCS. The improved clinical outcomes we have observed at our site and presented in this manuscript suggest there may be benefit of using routine intraoperative cell salvage in LSCS. Future research will be conducted to evaluate the economic outcomes associated with increased cell salvage use. Declarations Compliance with Ethical Standards: Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflicts of interest/Competing interests BF reports speaker fees from Vifor Pharma, Pfizer and the Heart Team Education Association outside the submitted work. TF, ET, AG, AP, RS, TK, NH have nothing to disclose. Ethical approval This study was approved by our Institutional Review Board (IRB), (CALHN Reference Number: 14994). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent Written informed consent was waived by the IRB. Author Contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Tom Fox, Evelyn Timpani, Amanda Licis, Romi Sinha, Nicolette Hodyl, Thu-Lan Kelly and Bernd Froessler. The first draft of the manuscript was written by Tom Fox and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. References Cai X, Ren M, Chen F et al. (2020) Blood transfusion during the COVID-19 outbreak. 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Anesthesiology 133 (1):16-18. doi:10.1097/aln.0000000000003341 VanderMeulen H, Strauss R, Lin Y et al. (2020) The contribution of iron deficiency to the risk of peripartum transfusion: a retrospective case control study. BMC Pregnancy Childbirth 20 (1):196. doi:10.1186/s12884-020-02886-z Teichman J, Nisenbaum R, Lausman A et al. (2021) Suboptimal iron deficiency screening in pregnancy and the impact of socioeconomic status in a high-resource setting. Blood Adv. doi:10.1182/bloodadvances.2021004352 Butwick AJ, McDonnell N (2021) Antepartum and postpartum anemia: a narrative review. Int J Obstet Anesth:102985. doi:10.1016/j.ijoa.2021.102985 Cite Share Download PDF Status: Published Journal Publication published 26 May, 2023 Read the published version in Archives of Gynecology and Obstetrics → Version 1 posted Reviewers agreed at journal 10 Mar, 2023 Editor invited by journal 26 Feb, 2023 Editor assigned by journal 24 Feb, 2023 First submitted to journal 23 Feb, 2023 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-2614829","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":182521803,"identity":"3bca4944-54a4-4a96-99f5-44cd86f9b7d3","order_by":0,"name":"Tom P Fox","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tom","middleName":"P","lastName":"Fox","suffix":""},{"id":182521804,"identity":"6eb805e0-2c1c-4a23-98c1-27ff6ca9e88e","order_by":1,"name":"Evelyn Timpani","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Evelyn","middleName":"","lastName":"Timpani","suffix":""},{"id":182521805,"identity":"2e94e5f5-5c59-4134-ac3f-baea46e5b8c0","order_by":2,"name":"Amanda Green","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Amanda","middleName":"","lastName":"Green","suffix":""},{"id":182521806,"identity":"1d15a30c-a9ce-478b-89dd-61debe95bf9f","order_by":3,"name":"Anupam Parange","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Anupam","middleName":"","lastName":"Parange","suffix":""},{"id":182521807,"identity":"4d19059c-1e98-4275-bad8-017d9058cf97","order_by":4,"name":"Romi Sinha","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Romi","middleName":"","lastName":"Sinha","suffix":""},{"id":182521808,"identity":"cb7fb15d-e734-4cc3-92e4-0de1bcb0ee87","order_by":5,"name":"Thu-Lan Kelly","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Thu-Lan","middleName":"","lastName":"Kelly","suffix":""},{"id":182521809,"identity":"d9f4294e-dd8c-4a74-8fa3-2cdb5b703f23","order_by":6,"name":"Nicolette A Hodyl","email":"","orcid":"","institution":"","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Nicolette","middleName":"A","lastName":"Hodyl","suffix":""},{"id":182521810,"identity":"c2a7b6b6-0cd7-4aea-a13a-f658eaff21a0","order_by":7,"name":"Bernd Froessler","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDklEQVRIie3PsWrCQBjA8S8ELkvA9URoXuELQkOgpa/yHYIuSocuGTo4nUvUtQGhr5BHEARd8gA31ZSA7eBw3UtRqw6lvYpbKfcfjvvgftwdgM32B8Pd4sPFfirhuDtNmvuJ4Lg7h4j+KRJ5w1W5BryteYNKU/LUeRxM3dc3CQFOfyZxuojCCWCcpcUlp+KulxfE4kxCmBsIqjZr+PCOqLoMhKReDsSafgGOkSxXO4KIy5dKiw/qBOPyk9yYb2EHogC56BOBIrfyExAmEqdtVp9sRT3tbv8ypzBXz9J5SHgrM5DImzO+ThBr3qLS+p6CYNyaaY1X1yMDOTzvy+RIDsB/O/89V5933maz2f55G/AfV9Ub4PKKAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0003-3755-8609","institution":"University of Adelaide Discipline of Acute Care Medicine","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Bernd","middleName":"","lastName":"Froessler","suffix":""}],"badges":[],"createdAt":"2023-02-22 06:33:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2614829/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2614829/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00404-023-07082-w","type":"published","date":"2023-05-26T20:57:47+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":34357749,"identity":"e20a8369-04bd-4699-84b9-7a82c358dd93","added_by":"auto","created_at":"2023-03-16 14:17:23","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":94417,"visible":true,"origin":"","legend":"\u003cp\u003eWeekly rates of cell salvage and post-partum IV iron and length of stay in 2020. Lines and shaded confidence bands are produced by lowess smoothing. The dashed vertical line indicates the start of mandated IOCS.\u003c/p\u003e\n\u003cp\u003eTIFF format, resolution 600 dpi, created in Rstudio\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-2614829/v1/e64154d69e602ea960e4379d.jpg"},{"id":44730225,"identity":"8fd0551f-b8f4-480b-ace1-23c9582fcdc4","added_by":"auto","created_at":"2023-10-16 21:28:15","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":341973,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2614829/v1/6044a19b-0378-4580-8feb-192e83aba3a8.pdf"}],"financialInterests":"","formattedTitle":"Association between routine Cell Salvage use for Lower Segment Caesarean Section and post-operative iron infusion and hemoglobin during the Covid-19 Pandemic","fulltext":[{"header":"take-home message","content":"\u003cp\u003eCell salvage provision during cesarean section is a valuable tool and reduces the incidence of post-partum anemia and the need for post-partum iron infusion. It may contribute to an avoidance or reduction of allogeneic red blood cell transfusion in the peri-partum setting.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eIn March 2020, the World Health Organization (WHO) declared a pandemic status for the coronavirus disease 2019 (COVID-19). In addition to the unprecedented pressures on health care systems, COVID-19 has had a profound impact on the number of blood donations, leaving blood services severely challenged to maintain their inventory during the pandemic.[\u003cspan class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e3\u003c/span\u003e] These challenges highlight the critical importance for Patient Blood Management (PBM) as an integral part of patient care. In a recent publication a multinational and diverse group of authors issued a \u0026ldquo;Call to Action\u0026rdquo; urging all stakeholders and providers to implement practical and multimodal principles of PBM.[\u003cspan class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/p\u003e\n\u003cp\u003ePBM is a patient-centered approach, applying an evidence-based bundle of care to preserve the patient\u0026rsquo;s own blood by managing anemia, minimizing iatrogenic blood loss, and harnessing tolerance to anemia to improve patient outcome.[\u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e] Intraoperative cell salvage (IOCS) is an integral and valuable component of PBM.[\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/p\u003e\n\u003cp\u003eThe benefits from IOCS have been known for some time.[\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e] Clinical adoption of IOCS in obstetrics for lower segment caesarean section (LSCS) has increased substantially, but despite this, the utilization of this technique varies considerably around the world.[\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e] At our institution, IOCS has been an established modality since 2013, as part of our hospital-wide PBM approach. Prior to April 2020, our institutional practice included initiation of IOCS during LSCS based on pre-operative anemia, patient risk assessment for intra-operative blood loss, post-partum hemorrhage and other individual patient factors.\u003c/p\u003e\n\u003cp\u003eIn response to the Australian National Blood Authority\u0026rsquo;s call to adhere to PBM guidelines and practices during the pandemic, in order to preserve finite reserves of donated blood, [\u003cspan class=\"CitationRef\"\u003e12\u003c/span\u003e] [\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e]members of the Departments of Anesthesia and Obstetrics at our institution discussed if modifications of our PBM practices were warranted to prevent the incidence and severity of peri-partum anemia. A decision was made to trial the mandated use of IOCS for all LSCS during the height of the first wave of the pandemic, to explore whether this practice could reduce the need for red blood cell (RBC) transfusion. We also aimed to examine the association of routine IOCS for LSCS on other indicators of optimal PBM, including the rate and volume of returned cell salvaged blood and the incidence and degree of post-partum anemia, as well as the impact on other maternal outcomes such as length of hospital stay.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis study was approved by our Institutional Review Board (IRB), (CALHN Reference Number: 14994). Written informed consent was waived by the IRB. We conducted a single-center non-overlapping before-after study of all obstetric patients undergoing either elective or emergent lower segment caesarean section over a four-month period in early 2020. Exclusion criteria were caesarean section for stillbirth or patient refusal of the utilization of cell salvage, which was discussed while obtaining anesthesia consent. This study adheres to The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement.[\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e\n\u003cp\u003eData from selective intra-operative cell salvage practice (06 February 2020\u0026ndash;05 April 2020) and the subsequent two months (06 April 2020-05 June 2020) with use of routine intra-operative shed blood collection was collected from electronic and paper records, after the completion of the study period. Participants were identified via electronic hospital records, using the search terms \u0026ldquo;LSCS\u0026rdquo; and \u0026ldquo;Caesarean\u0026rdquo; between the above dates. Anemia was defined as hemoglobin (Hb)\u0026thinsp;\u0026lt;\u0026thinsp;110 g/L during pregnancy and Hb\u0026thinsp;\u0026lt;\u0026thinsp;100 g/L post-partum.[\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e] The risk of bias was low, as for both groups, the recovered blood was processed when a substantial blood loss occurred, and the autologous RBC reinfusion volume was expected to reach 100 ml or more.\u003c/p\u003e\n\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e\n\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\n\u003cp\u003eDescriptive statistics summarized patient characteristics using counts and percentages for categorical data, means and standard deviations or medians and interquartile ranges for continuous data, as appropriate. To compare post-operative outcomes between the groups who were mandated IOCS or received usual care, t-tests for normally distributed continuous data, Kruskal-Wallis tests for skewed data, and chi-square tests for categorical data were used.\u003c/p\u003e\n\u003cp\u003ePost-partum iron infusion was modelled using logistic regression, and log-transformed length of stay with linear regression. Other outcomes, such as post-operative hemoglobin or anemia, were not modelled due to a large proportion of missing data. Differences between mandated IOCS and usual care were expressed as odds ratios for post-partum iron infusion and geometric mean ratios for length of stay, and 95% confidence intervals (CI). To account for potential confounding by differences in patients between time periods and type of care, a counterfactual approach with propensity modelling was used. The propensity model used mandated IOCS vs usual care as the outcome with covariates age, parity, gravida, ASA score, pre-operative Hb, operation type and anesthesia type. The propensity model was used to create trimmed, stabilized inverse probability weights (IPW). Standardized mean differences (SMD) were used to assess balance in covariates at baseline before and after weighting, where an SMD\u0026thinsp;\u0026gt;\u0026thinsp;0.1 was considered imbalanced.\u003c/p\u003e\n\u003cp\u003eFinally, to investigate the possibility that the changes over time could have occurred regardless of mandated IOCS, an interrupted time series (ITS) analysis, adapted for short time periods, was performed using the R package \u0026lsquo;its.analysis\u0026rsquo;. Post-partum IV iron and length of stay were aggregated by week to create time series. A significant difference in the outcome between the two periods was tested, accounting for important covariates and autocorrelation in the outcome over time. The ITS model for number of post-operative iron infusions per week used pre-operative anemia, operation type and primiparity as covariates, while the model for log-transformed length of stay included pre-operative Hb, emergency operation and primiparity rates.\u003c/p\u003e\n\u003cp\u003eStatistical significance was assessed at the p\u0026thinsp;=\u0026thinsp;0.025 level to account for two outcomes. R statistical software version 4.1.0 (R Foundation for statistical computing, Vienna Austria) was used for all statistical analyses.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 431 participants were included in the study. During the first two months, 203 women underwent caesarean section delivery and received usual care, while 228 women delivered during the period where IOCS was mandated for caesarean deliveries.\u003c/p\u003e\n\u003cp\u003eBefore inverse probability weighting, 6/9 pre-partum maternal characteristics were unbalanced with SMD\u0026thinsp;\u0026gt;\u0026thinsp;0.1 (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). After weighting, the imbalance was removed (all SMD\u0026thinsp;\u0026lt;\u0026thinsp;0.1).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMaternal demographic and obstetric data in two cohorts during periods of usual care or where intraoperative cell salvage (IOCS) was mandated for caesarean section deliveries.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMandated IOCS\u003c/p\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;228\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003eUsual Care\u003c/p\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;203\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003eUnweighted SMD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWeighted SMD\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAge, mean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e31 (5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e30 (6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.178\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGravida, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.5 (1\u0026ndash;3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e2 (1\u0026ndash;3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.118\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.027\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eParity, median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (0\u0026ndash;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e1 (0\u0026ndash;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCaesarean Section, n (%)\u003c/p\u003e\n \u003cp\u003eElective\u003c/p\u003e\n \u003cp\u003eEmergency\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e120 (53%)\u003c/p\u003e\n \u003cp\u003e108 (47%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e86 (42%)\u003c/p\u003e\n \u003cp\u003e117 (58%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.207\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eASA score, n (%)\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e64 (28%)\u003c/p\u003e\n \u003cp\u003e159 (70%)\u003c/p\u003e\n \u003cp\u003e5 (2%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e57 (28%)\u003c/p\u003e\n \u003cp\u003e141 (70%)\u003c/p\u003e\n \u003cp\u003e4 (2%)\u003c/p\u003e\n \u003cp\u003e1 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.069\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAnesthesia\u003c/p\u003e\n \u003cp\u003eSpinal\u003c/p\u003e\n \u003cp\u003eEpidural\u003c/p\u003e\n \u003cp\u003eGen. Anesthesia (GA)\u003c/p\u003e\n \u003cp\u003eCSE\u003c/p\u003e\n \u003cp\u003eCombination^\u003c/p\u003e\n \u003cp\u003e^Combinations included:\u003c/p\u003e\n \u003cp\u003eSpinal\u0026thinsp;+\u0026thinsp;GA\u003c/p\u003e\n \u003cp\u003eEpidural\u0026thinsp;+\u0026thinsp;GA\u003c/p\u003e\n \u003cp\u003eEpidural\u0026thinsp;+\u0026thinsp;Spinal\u0026thinsp;+\u0026thinsp;GA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e161 (71%)\u003c/p\u003e\n \u003cp\u003e42 (18%)\u003c/p\u003e\n \u003cp\u003e14 (6%)\u003c/p\u003e\n \u003cp\u003e5 (2)\u003c/p\u003e\n \u003cp\u003e6 (3%)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (1%)\u003c/p\u003e\n \u003cp\u003e4 (2%)\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e128 (63%)\u003c/p\u003e\n \u003cp\u003e55 (27%)\u003c/p\u003e\n \u003cp\u003e14 (7%)\u003c/p\u003e\n \u003cp\u003e2 (1%)\u003c/p\u003e\n \u003cp\u003e4 (2%)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e3 (2%)\u003c/p\u003e\n \u003cp\u003e1 (1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.204\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePre-operative Hb (g/L), mean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e125 (12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e124 (13)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.030\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePre-operative Anemia, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 (11%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e24 (12%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.075\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePre-operative IV iron, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 15.4384%;\"\u003e\n \u003cp\u003e22 (11%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\" style=\"width: 15.9341%;\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.043\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eThere was no difference in allogeneic RBC transfusion, with only one woman in each group receiving blood products. Univariate analysis showed that post-operatively, women in the Mandated IOCS group had higher post-operative Hb values, 111 g/L vs 102 g/L (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (despite similar pre-operative Hb, 125 g/L vs 124 g/L), had significantly lower rates of anemia, 48% vs 78% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and less often exposed to post-partum intravenous iron, 11% vs 3% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). A higher proportion of women in the Usual Care cohort had an emergency caesarean section (p\u0026thinsp;=\u0026thinsp;0.03), greater estimated blood loss (EBL) (p\u0026thinsp;=\u0026thinsp;0.003).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab2\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePost-operative Hb and anemia status of women according to use of mandated intraoperative cell salvage (IOCS).\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIOCS mandated\u003c/p\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;228\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUsual care\u003c/p\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;203\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ep\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCell Salvage deployed, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;227\u003c/p\u003e\n \u003cp\u003e196 (86%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;203\u003c/p\u003e\n \u003cp\u003e62 (31%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-operative\u003c/p\u003e\n \u003cp\u003eHb (g/L), mean (SD)\u003c/p\u003e\n \u003cp\u003eAnemia, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;71\u003c/p\u003e\n \u003cp\u003e111 (14)\u003c/p\u003e\n \u003cp\u003e14 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;95\u003c/p\u003e\n \u003cp\u003e102 (12)\u003c/p\u003e\n \u003cp\u003e39 (41%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReceived post-operative IV iron, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24 (11%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e26 (13%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.46\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEstimated blood loss (ml), median (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e400 (300\u0026ndash;600)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e500 (350\u0026ndash;700)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBlood reinfused, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e21 (9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6 (3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.008\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eReinfusion volume (ml), med (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;21\u003c/p\u003e\n \u003cp\u003e250 (134\u0026ndash;338)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003en\u0026thinsp;=\u0026thinsp;6\u003c/p\u003e\n \u003cp\u003e284 (245\u0026ndash;290)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.86\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003cp\u003eStatistical modelling showed that women who were mandated IOCS had lower rates of post-partum iron infusion (odds ratio (OR)\u0026thinsp;=\u0026thinsp;0.31, 95% CI\u0026thinsp;=\u0026thinsp;0.12 to 0.80, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.016) than women in the Usual Care group (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). After weighting, length of stay was not different between the groups (geometric mean ratio\u0026thinsp;=\u0026thinsp;0.93, 95% CI\u0026thinsp;=\u0026thinsp;0.86 to 1.004, p\u0026thinsp;=\u0026thinsp;0.063). These results were confirmed by the ITS analysis \u003cem\u003e(P\u0026thinsp;=\u003c/em\u003e\u0026thinsp;0.012 and \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.23 for post-partum iron and length of stay, respectively). Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e shows average weekly cell salvage and post-partum iron rates and length stay before and after mandated IOCS.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab3\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMultivariable statistical modelling with and without inverse probability weighting and interrupted time series (ITS) p-value for a difference between time periods.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOutcome\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUnweighted Estimate\u003c/p\u003e\n \u003cp\u003e(95% CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUnweighted P-value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWeighted Estimate (95% CI)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWeighted P-value\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eITS\u003c/p\u003e\n \u003cp\u003eP-value\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePost-partum IV iron\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.22 (0.09\u0026ndash;0.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.31 (0.12\u0026ndash;0.80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.016\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.012\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLength of Stay\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.90 (0.84\u0026ndash;0.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.93 (0.86\u0026ndash;1.004)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.063\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e1\u003c/sup\u003eOdds ratio for Yes vs No for mandated intraoperative cell salvage vs Usual Care\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\"\u003e\u003csup\u003e2\u003c/sup\u003eGeometric mean ratio for mandated intraoperative cell salvage vs Usual Care\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe introduction of routine IOCS for caesarean deliveries during the early phase of the COVID-19 pandemic resulted in higher processing rates and reinfusion volumes of autologous RBC. Consequently, post-partum Hb values were improved and anemia less prevalent in women from this cohort. Intravenous iron prescription occurred less often after delivery, and there was no difference in allogeneic RBC transfusion rates between the two groups. These finding add to the existing evidence demonstrating the safety and efficacy of autologous salvaged blood in the context of LSCS, through conservation of patient blood and maintained iron stores.\u003c/p\u003e \u003cp\u003eAfter accounting for difference between patients at baseline, mandating cell salvage reduced post-operative iron infusion rates. Length of stay however, appeared to be in decline prior to the COVID restrictions and there was no significant difference between the time periods.\u003c/p\u003e \u003cp\u003eAlthough not contradicted in this study, IOCS has been shown to reduce the need for allogeneic transfusion of RBC in other surgical settings.[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] In 2012, Liumbruno et al labelled IOCS \u0026ldquo;the most practical, effective and useful blood conservation technique in obstetrics\u0026rdquo;.[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] Due to comprehensive staff education and general enthusiasm for the implementation for PBM among staff across disciplines at our hospital, IOCS was introduced in 2013 for elective and emergency surgery. It quickly became an essential tool of managing maternal bleeding, combined with a specific obstetric hemorrhage bleeding protocol and point-of-care coagulation monitoring. This comprehensive obstetric PBM approach resulted in the lowest RBC transfusion rate in South Australia (personal communication, South Australian Blood, Organ and Tissue Programs). The trial period of mandated IOCS in response to the limited blood availability during COVID-19 pandemic, demonstrated no further reduction in RBC transfusion rate. It was however, associated with an improvement in Hb status and reduced rates of post-partum iron deficiency anemia in the Mandated IOCS group compared to those receiving Usual Care. These outcomes may explain the 69% four-month trial period highlight the benefits for the patient derived from utilization of IOCS for LSCS.\u003c/p\u003e \u003cp\u003eThis study has highlighted the valuable contribution of IOCS in obstetric patient care. The mandated use of IOCS enhanced the effectiveness of an established and successful PBM approach, adding to the pre-existing strong body of evidence. Over the last decade the outcomes for over 2000 cases of autologous RBC re-infusion after red blood cell recovery during LSCS have been published in the literature. This research has demonstrated the safety, efficacy, and benefits of IOCS, [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] regardless of technique, for example differing suction set ups, the use or absence of leucocyte depletion filters, and selective versus routine cell salvage provision.\u003c/p\u003e \u003cp\u003eMaternal mortality is increasing in the United States and many parts of the world.[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] Obstetric hemorrhage is the most common cause for maternal death and consequently peri-partum RBC transfusion rates are on the rise, accounting for approximately 3% of all RBC transfusions.[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] It is important to emphasize that these transfusion events occur in young women, who potentially suffer long-term consequences from the exposure to allogeneic RBC\u0026rsquo;s.[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] Bleeding during child birth can be life-threatening and is notoriously difficult to predict.[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] IOCS in obstetrics is recommended by organizations such as The Association of Anaesthetists of Great Britain and Ireland, The National Institute for Health and Clinical Excellence, The American College of Obstetrics \u0026amp; Gynaecology, The Australian National Blood Authority, the Network for the Advancement of Patient Blood Management, Haemostasis and Thrombosis and the German/Austrian/Swiss Societies of Gynecology and Obstetrics (DGGG, OEGGG, SGGG).[\u003cspan additionalcitationids=\"CR23 CR24 CR25 CR26\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eHowever, the availability of this important tool is far from universal and often absent, even in many large obstetric services. In a recent publication, Hofmann et al screened international efforts and strategies to identify the four main drivers for successful PBM implementation: patient outcomes, cost savings, preventing blood shortages and patient safety.[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] Whether routine IOCS in obstetrics is cost saving remains unclear, the use of red cell recovery and autotransfusion clearly supports improved patients outcomes, improved patient safety and prevention of blood shortages, all of which have been urgently required during the COVID-19 pandemic.[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eWithholding the provision of IOCS in obstetrics deprives women of the safest form of RBC transfusion, exposing them to preventable anemia and the well-known risks of allogeneic transfusion. Clinicians from around the world caring for women during childbirth should strengthen their efforts to establish IOCS as an integrated modality on a much broader scale.[\u003cspan additionalcitationids=\"CR31\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eLimitations\u003c/p\u003e \u003cp\u003eThe two-month trial of mandated IOCS at our site limited the number of patients included in this study. While we did observe higher rates of re-infusion in the mandated group, a much larger sample size would be required to detect any difference in the donor blood transfusion rates. This sample size would depend on the baseline rate of transfusion, which is already low at our site given our established PBM program. Nonetheless, the benefits of IOCS were still apparent, including lower rates of iron-deficient anemia, a higher post-operative Hb.\u003c/p\u003e \u003cp\u003eIn the Usual Care group, cell salvage was initiated for 31% (n\u0026thinsp;=\u0026thinsp;62/203) women while 86% of women (n\u0026thinsp;=\u0026thinsp;196/227) had cell salvage initiated following the mandate. The uptake of cell salvage following the introduction of the mandate started at 48% in week 1, increasing to 93% in week 2. It then remained high throughout the two-month period, ranging from 75\u0026ndash;96%. Reasons for IOCS not being used include some staff being unaware of new trial clinical protocol and clinician preference.\u003c/p\u003e \u003cp\u003eInterestingly in this study, the EBL was lower in the IOCS Mandate group compared to the Usual Care group. Multiple factors may have contributed to this finding, including the higher number of emergency caesarean sections in the Usual Care IOCS group. In addition, the single cell salvage set-up may have limited observation of any blood loss, which is already notoriously inaccurate as it relied on visual assessment.\u003c/p\u003e \u003cp\u003eDue to a functional PBM program at our hospital, cell salvage was already occurring in the routine care group, before it was mandated. This represents confounding and may reduce the significance of our observed results. However, it was not the purpose of the study to test cell salvage vs no cell salvage.\u003c/p\u003e \u003cp\u003eThe authors acknowledge that while statistically significant results were observed, the clinical significance of this is less certain. We also acknowledge that a study with a significantly larger sample size is required to observe differences in donor transfusion rates and indeed overall cost effectiveness of mandated IOCS.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eRoutine cell salvage provision during LSCS associated with an increased post-operative hemoglobin and reduced anemia incidence which may contribute to an avoidance of limited blood products. We also observed a reduction in post-partum iron infusions. Currently, there are a number of barriers to the routine use of IOCS at some sites, including a lack of awareness and funding to support IOCS establishment and protocols for routine IOCS. The improved clinical outcomes we have observed at our site and presented in this manuscript suggest there may be benefit of using routine intraoperative cell salvage in LSCS. Future research will be conducted to evaluate the economic outcomes associated with increased cell salvage use.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eCompliance with Ethical Standards:\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003eConflicts of interest/Competing interests\u003c/p\u003e\n\u003cp\u003eBF reports speaker fees from Vifor Pharma, Pfizer and the Heart Team Education Association outside the submitted work. TF, ET, AG, AP, RS, TK, NH have nothing to disclose.\u003c/p\u003e\n\u003cp\u003eEthical approval\u003c/p\u003e\n\u003cp\u003eThis study was approved by our Institutional Review Board (IRB), (CALHN Reference Number: 14994). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.\u003c/p\u003e\n\u003cp\u003eInformed consent\u003c/p\u003e\n\u003cp\u003eWritten informed consent was waived by the IRB.\u003c/p\u003e\n\u003cp\u003eAuthor Contributions\u003c/p\u003e\n\u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Tom Fox, Evelyn Timpani, Amanda Licis, Romi Sinha, Nicolette Hodyl, Thu-Lan Kelly and Bernd Froessler. The first draft of the manuscript was written by Tom Fox and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCai X, Ren M, Chen F et al. (2020) Blood transfusion during the COVID-19 outbreak. Blood transfusion = Trasfusione del sangue 18 (2):79-82. doi:10.2450/2020.0076-20\u003c/li\u003e\n\u003cli\u003eMascaretti L, De Angelis V, Berti P (2020) The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and Transfusion Medicine: reflections from Italy. Blood transfusion = Trasfusione del sangue 18 (2):77-78. doi:10.2450/2020.0071-20\u003c/li\u003e\n\u003cli\u003eNgo A, Masel D, Cahill C et al. (2020) Blood Banking and Transfusion Medicine Challenges During the COVID-19 Pandemic. Clinics in laboratory medicine 40 (4):587-601. doi:10.1016/j.cll.2020.08.013\u003c/li\u003e\n\u003cli\u003eShander A, Goobie SM, Warne MA et al. (2020) The Essential Role of Patient Blood Management in a Pandemic: A Call for Action. Anesth Analg. doi:10.1213/ane.0000000000004844\u003c/li\u003e\n\u003cli\u003eMeybohm P, Froessler B, Goodnough LT et al. (2017) \u0026ldquo;Simplified International Recommendations for the Implementation of Patient Blood Management\u0026rdquo; (SIR4PBM). Perioperative Medicine 6 (1):5. doi:10.1186/s13741-017-0061-8\u003c/li\u003e\n\u003cli\u003eMeybohm P, Choorapoikayil S, Wessels A et al. (2016) Washed cell salvage in surgical patients. A review and meta-analysis of prospective randomized trials under PRISMA. Medicine 95. doi:10.1097/md.0000000000004490\u003c/li\u003e\n\u003cli\u003eScott AV, Nagababu E, Johnson DJ et al. (2016) 2,3-Diphosphoglycerate Concentrations in Autologous Salvaged Versus Stored Red Blood Cells and in Surgical Patients After Transfusion. Anesth Analg 122 (3):616-623. doi:10.1213/ane.0000000000001071\u003c/li\u003e\n\u003cli\u003eFrank SM (2011) Who benefits from red blood cell salvage?--Utility and value of intraoperative autologous transfusion. 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Available at https://www.who.int/publications/i/item/9789241564960, accessed 23/10/2021.\u003c/li\u003e\n\u003cli\u003evon Elm E, Altman DG, Egger M et al. (2007) Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Bmj 335 (7624):806-808. doi:10.1136/bmj.39335.541782.AD\u003c/li\u003e\n\u003cli\u003eLiumbruno GM, Liumbruno C, Rafanelli D (2012) Autologous blood in obstetrics: where are we going now? Blood transfusion = Trasfusione del sangue 10 (2):125-147. doi:10.2450/2011.0010-11\u003c/li\u003e\n\u003cli\u003eWang R, Luo T, Liu Z et al. (2020) Intraoperative cell salvage is associated with reduced allogeneic blood requirements and has no significant impairment on coagulation function in patients undergoing cesarean delivery: a retrospective study. Archives of Gynecology and Obstetrics 301 (5):1173-1180. doi:10.1007/s00404-020-05500-x\u003c/li\u003e\n\u003cli\u003eKhan KS, Moore PAS, Wilson MJ et al. (2017) Cell salvage and donor blood transfusion during cesarean section: A pragmatic, multicentre randomised controlled trial (SALVO). PLoS Med 14 (12):e1002471. doi:10.1371/journal.pmed.1002471\u003c/li\u003e\n\u003cli\u003ePatterson JA, Roberts CL, Bowen JR et al. (2014) Blood transfusion during pregnancy, birth, and the postnatal period. Obstet Gynecol 123 (1):126-133. doi:10.1097/aog.0000000000000054\u003c/li\u003e\n\u003cli\u003eThurn L, Wikman A, Westgren M et al. (2019) Incidence and risk factors of transfusion reactions in postpartum blood transfusions. Blood Advances 3 (15):2298-2306. doi:10.1182/bloodadvances.2019000074\u003c/li\u003e\n\u003cli\u003eUkah U, Platt R, Potter B et al. (2020) Obstetric haemorrhage and risk of cardiovascular disease after three decades: a population-based cohort study. BJOG: An International Journal of Obstetrics \u0026amp; Gynaecology 127 (12):1489-1497. doi:https://doi.org/10.1111/1471-0528.16321\u003c/li\u003e\n\u003cli\u003eCollis R, Guasch E (2017) Managing major obstetric haemorrhage: Pharmacotherapy and transfusion. Best Pract Res Clin Anaesthesiol 31 (1):107-124. doi:10.1016/j.bpa.2017.02.001\u003c/li\u003e\n\u003cli\u003eMunoz M, Stensballe J, Ducloy-Bouthors AS et al. (2019) Patient blood management in obstetrics: prevention and treatment of postpartum haemorrhage. A NATA consensus statement. Blood transfusion = Trasfusione del sangue. doi:10.2450/2019.0245-18\u003c/li\u003e\n\u003cli\u003eKlein AA, Bailey CR, Charlton AJ et al. (2018) Association of Anaesthetists guidelines: cell salvage for peri-operative blood conservation 2018. Anaesthesia 73 (9):1141-1150. doi:10.1111/anae.14331\u003c/li\u003e\n\u003cli\u003eAuthority NB (2015) Patient Blood Management Guidelines: Module 5 Obstetrics and Maternity. https://www.blood.gov.au/pbm-module-5. Accessed 5/10/2021 2021\u003c/li\u003e\n\u003cli\u003eACOG committee opinion. Placenta accreta. Number 266, January 2002. American College of Obstetricians and Gynecologists (2002). Int J Gynaecol Obstet 77 (1):77-78. doi:10.1016/s0020-7292(02)80003-0\u003c/li\u003e\n\u003cli\u003e(NICE) TNIfHaCE (2005) Intraoperative blood cell salvage in obstetrics. https://www.nice.org.uk/guidance/IPG144. Accessed 6/10/2021 2021\u003c/li\u003e\n\u003cli\u003eSchlembach D, Helmer H, Henrich W et al. (2018) Peripartum Haemorrhage, Diagnosis and Therapy. Guideline of the DGGG, OEGGG and SGGG (S2k Level, AWMF Registry No.\u0026thinsp;015/063, March 2016). Geburtshilfe Frauenheilkd 78 (4):382-399. doi:10.1055/a-0582-0122\u003c/li\u003e\n\u003cli\u003eHofmann A, Spahn DR, Holtorf AP (2021) Making patient blood management the new norm(al) as experienced by implementors in diverse countries. BMC Health Serv Res 21 (1):634. doi:10.1186/s12913-021-06484-3\u003c/li\u003e\n\u003cli\u003eGehrie EA, Frank SM, Goobie SM (2020) Balancing Supply and Demand for Blood during the COVID-19 Pandemic. Anesthesiology 133 (1):16-18. doi:10.1097/aln.0000000000003341\u003c/li\u003e\n\u003cli\u003eVanderMeulen H, Strauss R, Lin Y et al. (2020) The contribution of iron deficiency to the risk of peripartum transfusion: a retrospective case control study. BMC Pregnancy Childbirth 20 (1):196. doi:10.1186/s12884-020-02886-z\u003c/li\u003e\n\u003cli\u003eTeichman J, Nisenbaum R, Lausman A et al. (2021) Suboptimal iron deficiency screening in pregnancy and the impact of socioeconomic status in a high-resource setting. Blood Adv. doi:10.1182/bloodadvances.2021004352\u003c/li\u003e\n\u003cli\u003eButwick AJ, McDonnell N (2021) Antepartum and postpartum anemia: a narrative review. Int J Obstet Anesth:102985. doi:10.1016/j.ijoa.2021.102985\u003c/li\u003e\n\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":"archives-of-gynecology-and-obstetrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"arch","sideBox":"Learn more about [Archives of Gynecology and Obstetrics](https://www.springer.com/journal/404)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/arch/default.aspx","title":"Archives of Gynecology and Obstetrics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-2614829/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2614829/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eIntraoperative cell salvage is central to Patient Blood Management including for lower segment caesarean section. Prior to April 2020, we initiated intraoperative cell salvage during caesarean section based on risk assessment for hemorrhage and patient factors. As the pandemic broadened, we mandated intraoperative cell salvage to prevent peri-partum anemia and potentially reduce blood product usage. We examined the association of routine intraoperative cell salvage on maternal outcomes.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e We conducted a single-center non-overlapping before-after study of obstetric patients undergoing lower segment caesarean section in the 2 months prior to change in practice (\u0026lsquo;usual care\u0026thinsp;=\u0026thinsp;selective intraoperative cell salvage\u0026rsquo;, n\u0026thinsp;=\u0026thinsp;203) and the 2 months following (\u0026lsquo;mandated intraoperative cell salvage\u0026rsquo;, n\u0026thinsp;=\u0026thinsp;228). Recovered blood was processed when a minimal autologous reinfusion volume of 100 ml was expected. Post-operative iron infusion and length of stay were modelled using logistic or linear regression, using inverse probability weighting to account for confounding.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eMore emergency lower segment caesarean sections occurred in the Usual Care group. Compared to the Usual Care group, post-operative hemoglobin was higher and anemia cases fewer in the Mandated intraoperative cell salvage group. Rates of post-partum iron infusion were significantly lower in the Mandated intraoperative cell salvage group (OR\u0026thinsp;=\u0026thinsp;0.31, 95% CI\u0026thinsp;=\u0026thinsp;0.12 to 0.80, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.016). No difference was found for length of stay.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eRoutine cell salvage provision during lower segment caesarean section was associated with a significant reduction in post-partum iron infusions, increased post-operative hemoglobin and reduced anemia prevalence.\u003c/p\u003e","manuscriptTitle":"Association between routine Cell Salvage use for Lower Segment Caesarean Section and post-operative iron infusion and hemoglobin during the Covid-19 Pandemic","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-03-16 14:17:18","doi":"10.21203/rs.3.rs-2614829/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2023-03-10T19:00:52+00:00","index":0,"fulltext":""},{"type":"editorInvited","content":"Archives of Gynecology and Obstetrics","date":"2023-02-26T20:59:24+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-02-24T12:04:20+00:00","index":"","fulltext":""},{"type":"submitted","content":"Archives of Gynecology and Obstetrics","date":"2023-02-23T16:29:34+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"archives-of-gynecology-and-obstetrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"arch","sideBox":"Learn more about [Archives of Gynecology and Obstetrics](https://www.springer.com/journal/404)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/arch/default.aspx","title":"Archives of Gynecology and Obstetrics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"6d7658ba-dc2a-451d-866a-7500af0a199b","owner":[],"postedDate":"March 16th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-10-16T21:13:40+00:00","versionOfRecord":{"articleIdentity":"rs-2614829","link":"https://doi.org/10.1007/s00404-023-07082-w","journal":{"identity":"archives-of-gynecology-and-obstetrics","isVorOnly":false,"title":"Archives of Gynecology and Obstetrics"},"publishedOn":"2023-05-26 20:57:47","publishedOnDateReadable":"May 26th, 2023"},"versionCreatedAt":"2023-03-16 14:17:18","video":"","vorDoi":"10.1007/s00404-023-07082-w","vorDoiUrl":"https://doi.org/10.1007/s00404-023-07082-w","workflowStages":[]},"version":"v1","identity":"rs-2614829","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2614829","identity":"rs-2614829","version":["v1"]},"buildId":"GqpaHPwrfC8PjnIFayRh5","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}