The effects of regional anesthesia combined with awake delayed extubation in patients undergoing esophageal cancer surgery: a single-blind randomized controlled trial

The effects of regional anesthesia combined with awake delayed extubation in patients undergoing esophageal cancer surgery: a single-blind randomized controlled trial | 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 Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The effects of regional anesthesia combined with awake delayed extubation in patients undergoing esophageal cancer surgery: a single-blind randomized controlled trial Jinghao Yang, Yihang He, Jing Lin, Shan Yu, Yongliang Chang, Youbo Zuo This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3850116/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: Postoperative pulmonary complications (PPCs) are the most frequent complications after esophagectomy, which usually causes to hypoxemia. The aim of this study is to evaluate whether regional anesthesia combined with awake delayed extubation improves postoperative oxygenation index after esophagectomy. Methods: Ninety patients diagnosed with esophageal cancer undergoing elective thoracolaparoscopic esophagectomy were randomized to three groups, control group (C group), regional anesthesia group (N group) and regional anesthesia combined with awake delayed extubation group (ND group). Regional anesthesia included serratus anterior plane block, transversus abdominis plane block, and rectus abdominis sheath block. Awake delayed extubation was defined as removing the endotracheal tube 30 min after waking up. The primary outcome was postoperative oxygenation index; secondary outcomes were the incidence of PPCs, analgesics consumption, postoperative pain scores, time to first flatus, time to first defecation, and hospital stays. Results: The oxygenation index of ND group was significantly higher than the N group（ P ＜0.05) and C group（ P <0.05) at 1 hour and 24 hours postoperatively. The incidence of PPCs was significantly lower in the ND group than in the N group and C group (61.5% vs.51.8% vs. 25.9%, p = 0.026 * ). Conclusion: Regional anesthesia combined with awake delayed extubation can significantly improve postoperative oxygenation index, reduce the incidence of PPCs, and promote patient recovery after thoracolaparoscopic esophageal cancer surgery. Trial registration: The study was registered on Chinese Clinical Trial Registry, (ChiCTR2200066726) on 12/05/2023. Oxygenation index Awake delayed extubation Regional anesthesia Postoperative pulmonary complications Esophagectomy Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Esophageal cancer is one of the most common cancers worldwide, and surgical resection is one of the mainly clinical treatments for esophageal cancer[ 1 , 2 ]. However, esophagectomy is associated with a high risk of postoperative morbidity and mortality, even with the development of minimally invasive endoscopic surgery and enhanced recovery programs[ 3 ]. Postoperative pulmonary complications (PPCs) are the most common complications after esophageal cancer surgery, with an incidence of up to 52%[ 4 ]. Atelectasis, pneumonia and respiratory failure are the main PPCs. These complications usually lead to hypoxaemia, an increase in hospital stays, intensive care unit admission rate and mortality, and decreased quality of life[ 5 , 6 ]. As PPCs is a common cause of death following esophagectomy, improving postoperative oxygenation through decreased PPCs may further improve outcome. Ideal postoperative analgesia contributes to the patient’s cough and expectoration, and would decrease complications such as hypoxemia, atelectasis, and pulmonary infection. Zhang et al. reported that continuous paravertebral block analgesia increased the satisfaction of postoperative analgesia and decreased the incidence of pulmonary complications for patients undergoing minimally invasive esophagectomy (MIE)[ 7 ]. However, Brovman found that the regional anesthetic techniques were not associated with a lower incidence of pulmonary complications in lobectomy surgery[ 8 ]. The MIE usually suffers long operation time and vast area of trauma that often involves neck, chest, and abdomen. The trauma and esophageal anastomosis at the neck after MIE would increase secretions. The poor pharyngeal clearance of secretions could lead to laryngeal penetration and aspiration, and aspiration pneumonia[ 9 , 10 ] and the patients of MIE in the early stages of anesthesia recovery usually have no sufficient airway protection. Additionally, previous studies have reported severe secretion retention in patients with a tracheostomy tube than in those without. Good analgesia improves cough, however, postoperative sputum expectoration is still difficult. Intraoperative lung recruitment, including lung protection ventilation strategy, have demonstrated the effectiveness in improving intraoperative oxygenation and early respiratory compliance, but not consistently translate into lower PPCs[ 11 ]. Strategies aiming to maintain lung recruitment in the post-anesthesia care unit, ICU or surgical ward may independently improve postoperative outcomes and be at least as valuable as intraoperative lung expansion interventions. Respiratory physiotherapy, consisting of a set of techniques for mobilizing and eliminating pulmonary secretions, could minimize pulmonary complications in mechanically ventilated patients[ 11 – 13 ]. However, few studies have analyzed the effectiveness of respiratory physiotherapy during extubation in prevention of hypoxemia for MIE patients. In the present study, we aimed to determine whether awake delayed extubation combined with respiratory physiotherapy improves postoperative oxygenation after esophagectomy. Methods Patients This study was conducted as a single-blind and controlled trial. The inclusion criteria were patients diagnosed with esophageal cancer scheduled for minimally invasive esophagectomy, aged 18 − 79 years, physical status of I to III, according to the American Society of Anesthesiologists (ASA), and body mass index (BMI) between 18 and 30 kg / m 2 . Exclusion criteria were diaphragmatic dysfunction, severe immune system diseases, severe cardio-cerebrovascular disease allergy to local anesthetics, chronic opioid use prior to esophagectomy, renal failure, and inability to provide informed consent. Patients would be excited if the minimally invasive surgery converted to open surgery, operation time was more than 6 hours, or blood loss was more than 600 mL. The study complied with the principles of the Declaration of Helsinki and was approved by the Ethics Committee of the Affiliated Hospital of North Sichuan Medical College, No: 2022ER238-1. The study was registered at www.chictr.org.cn (identity number ChiCTR2200066726). Written informed consent and information release approvals were obtained from all patients before they participated. Randomization and intervention Ninety patients diagnosed with esophageal cancer undergoing elective thoracolaparoscopic esophagectomy were randomly divided into three groups in a 1:1:1 ratio: the controlled group (C group), the regional anesthesia group (N group), and the regional anesthesia combined with the awake extubation group (ND group). The randomization was conducted by randomization numbers generated by SPSS. Randomization results were kept in a sealed envelope and sent to an independent anesthesiologist who performed the regional anesthesia on the morning of surgery. Staff involved in data collection and analysis were blinded to group assignment. The anesthesiologists guiding the intervention, the participants and the coordinating researcher were not blinded for allocation. The patients in the C group didn’t receive any regional analgesic technique. The patients in the N group received ultrasound guided serratus anterior plane block (SAPB) with 30 mL of 0.33% ropivacaine, and the combination block of bilateral transversus abdominis plane block (TAPB) and rectus abdominis sheath block (RSB) with 10 mL of 0.25% ropivacaine in each plane by one puncture technique. Based on the regional blocks, the patients in the ND group received awake delayed extubation which means removing the endotracheal tube 30 min after waking up. All patients received postoperative patient controlled intravenous analgesia (PCIA) after surgery. Anesthesia and surgery After the patient entering the operation room, peripheral venous access was routinely established, pulse oximetry, electrocardiogram and noninvasive blood pressure were monitored, and radial artery cannulation were performed under local anesthesia to monitor invasive arterial pressure. Patients in groups N and ND received ultrasound-guided right serratus anterior plane block (SAPB) and bilateral rectus abdominis sheath block (RSB) combined transversus abdominis plane block (TAPB) under sedation and analgesia before anesthesia induction, while group C received no regional block. Anesthesia induction was performed with midazolam 0.03 mg / kg, sufentanil 0.3–0.5 µg / kg, propofol 1.5-2 mg / kg and cisatracurium 0.15 mg / kg. Single-lumen endotracheal intubation was performed 3–5 min after induction. Anesthesia was maintained with sevoflurane, intermittent intravenous injection of sufentanil and cisatracurium. The anesthetic dosage was continuously adjusted according to the mean arterial pressure within 20% of the baseline value. Intraoperative intravenous dexmedetomidine 0.5 µg / (kg*h) was pumped intravenously within 10 min, and then 0.4 µg / (kg*h) was continuously pumped intravenously until 30 min before closure of the incision. A lung protective ventilation strategy throughout the operation was applied, including limiting tidal volume (6–8 mL / kg), positive end-expiratory pressure (5 cm H 2 O), maneuver recruitment and low fraction of inspired oxygen (40%-60%). The ventilatory frequency was adjusted to maintain the end-tidal carbon dioxide pressure between 35 and 45 mmHg. Ephedrine was administrated if the blood pressure was more than 20% below the baseline, and atropine was administered if the heart rate was lower than 50 bpm. At the end of surgery, postoperative analgesia was performed with a patient-controlled intravenous analgesia (PCIA) device. PCIA analgesia in all patients consisted of 150 ug sufentanil, 10 mg tropisetron with saline to 150 mL, a background infusion dose of 2 mL / h, and a bolus dose of 0.5 mL, with a 15-minute lockout time and a maximum of 10mL over 1 hour. When the VAS score was above 4, patients received intravenous tramadol (100 mg) as rescue analgesia. Neuromuscular blockade was reversed by neostigmine and glycopyrrolate when the return of spontaneous breathing appeared after surgery. All patients will undergo MIE with two-field lymphadenectomy, gastric conduit reconstruction, and an intrathoracic anastomosis. The operation was performed by conventional thoracolaparoscopic surgery. The procedure starts with an abdominal laparoscopic phase, which involves mobilization of the stomach, abdominal lymphadenectomy and gastric conduit construction. Then, the patient will be placed in (semi) prone position for thoracoscopy to mobilize the esophagus and perform a mediastinal lymphadenectomy. One of the trocarports is widened to a mini-thoracotomy for specimen extraction and when indicated, for the creation of the anastomosis. Gastrointestinal continuity is finally restored by a stapled or hand-sewn intrathoracic esophagogastric anastomosis. A maximum of one thoracic drain is placed on each side. Ultrasound guided SAPB, TAPB, and RSB The patients in the N and ND group received SAPB, and one-puncture technique of RSB combined with TAPB. The block was performed by a qualified anesthesiologist using ultrasound guidance (Mindray M9 Ultrasound System) and a high-frequency linear ultrasound probe. Firstly, the right SAPB was located between the fourth and fifth ribs of the midaxillary line, and 30 mL 0.33% ropivacaine was injected. Secondly, the probe was placed transversely in the midline of abdomen between the xiphoid process and the umbilicus, and moved outward along the costal margin, showing the rectus abdominis overlapping on the transverse abdominis (Fig. 1 a). The needle was inserted from inner side, and when the tip of the needle reached to the posterior rectus sheath, 0.5 mL saline was injected to adjust its position. Then, 10 mL of 0.25% ropivacaine was administered, and we can see local anesthetic spread inward. Then, the needle broke through the posterior rectus sheath, and 10 mL of 0.25% ropivacaine was injected, local anesthetic spreading outward. After the completion of the block, one membrane double capsule of ultrasound signs would be found (Fig. 1 b). The same block operation was performed on the opposite side. Awake delayed extubation and respiratory physiotherapy At the end of the operation, 5 mL of 2% lidocaine was instilled through the endotracheal tube, and drain the air in the balloon at the same time, letting the local anesthetic distribute around the balloon, then the balloon was re-inflated. After the patient was fully awake, respiratory physiotherapy techniques that consist of lateral rotation, manual lung hyperinflation, tapotement and aspiration, were applied[ 13 ]. Let the patient in right tilt position associated with manually tapotement to facilitate the mobilization and drainage of the secretions away from the bottom of pulmonary, using the force of gravity. Then aspiration was administrated using a disposable sputum aspirator with sputum collector, the sputum volume was collected, and the tube was removed after 30 min. Oxygenation and postoperative pulmonary complication Arterial blood samples were collected before anesthesia (T0), at 1 hour after extubation (T1), and 24 hours after operation (T2) for blood gas analysis, oxygenation index was calculated based on arterial partial oxygen level (PaO 2 ) and FIO 2 . The PPCs of the patients were defined according to the guidelines for European perioperative clinical outcome (EPCO) definitions, including pulmonary atelectasis, pneumonia, respiratory failure and pleural effusion. Patients were instructed preoperatively to use a visual analog scale (VAS) ranging from 0 cm (no pain) to 10 cm (most severe pain) and the PCIA pump device. Sample size calculation The sample size for the study was calculated based on a pilot study of 5 patients per group. The mean oxygenation index was 293 ± 53 in the N group and 340 ± 64 in the ND group. Assuming a two-sided type I error of 0.05 and type II error of 0.20 which eventually brings a power of 0.80 (1-β), 24 participants were needed per group. Considering possible drop-outs, we included at least 30 patients per group. Statistical analysis SPSS 21.0 statistical software was used for data analysis. Continuous variables were expressed as mean ± standard deviation (SD) or median (interquartile range, IQR) and were compared using one-way analysis of variance (ANOVA). Categorical variables were described as frequencies (percentages), and comparisons were done by chi-square or Fisher's exact tests. Comparison of the three treatment groups of continuous variables satisfying normal distribution and chi-square was analyzed by ANOVA, and further two-by-two comparisons were made using the least squares test of variance. For variables that did not satisfy normal distribution and chi-square, the Kruskal-Wallis test was used to compare the three treatment groups, and further two-by-two comparisons were made using the Bonferroni correction. Results A total of 96 patients were selected in this study. Six patients were excluded. The remaining 90 patients were randomly assigned to group C, N, and ND (n = 30). During the trial, 10 patients lost to follow-up, and 80 patients were included in the final analyses (Fig. 2 ). Pre- and intraoperative data There was no significant difference in demographic parameters, operation conditions, fluid and anesthetic administration among three groups ( P > 0.05, Table 1 ). Intraoperative sufentanil consumption was significantly smaller in the ND group than in the C group. The awake time of the patients was significantly smaller in the ND group than in the C group. Table 1 The demographic data and perioperative characteristics of the three groups Variables C group (n = 26) N group (n = 27) ND group (n = 27) p value Male / Female (n) 23/3 21/6 22/5 0.584 Age (year) 65.77 ± 6.99 67.86 ± 6.32 63.37 ± 7.56 0.399 BMI (kg / m 2 ) 23.42 ± 2.76 22.67 ± 2.76 22.84 ± 2.91 0.599 ASA (Ⅱ / Ⅲ) 21/5 21/6 21/6 0.955 Comorbidities, n (%) Hypertension (n) 5(19.2) 8(29.6) 3(11.1) 0.234 Diabetes (n) 1(3.8) 1(3.7) 0(0) 0.593 COPD (n) 1(3.8) 2(7.4) 4(14.8) 0.352 Anesthesia time (min) 286.00 ± 62.11 283.81 ± 57.00 276.59 ± 40.63 0.801 Operation time (min) 226.96 ± 51.51 221.56 ± 38.08 219.63 ± 28.45 0.791 Intraoperative sufentanil consumption (µg) 67.12 ± 14.01 51.00 ± 11.17 51.39 ± 10.16 0.0001 *** Awaking time(min) 65.08 ± 47.84 39.37 ± 45.51 37.96 ± 18.82 0.0023 ** Pacu time(min) 86.81 ± 38.21 92.59 ± 49.49 72.22 ± 19.87 0.133 Colloid volume (mL) 1780.77 ± 320.02 1707.41 ± 431.00 1696.30 ± 363.19 0.579 Crystal volume (mL) 550.00 ± 202.48 518.52 ± 168.79 507.41 ± 38.49 0.674 Blood loss (mL) 86.35 ± 35.54 87.78 ± 17.83 100.74 ± 54.41 0.334 Urine volume (mL) 521.15 ± 294.68 485.19 ± 328.11 464.81 ± 176.40 0.751 additional sputum volume(mL) 3.96(1,15) Variables are expressed as Mean ± SD, number or Median (interquartile range). BMI body mass index, ASA American Society of Anesthesiology. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001. Postoperative data At 1 hour and 24 hours postoperatively, the oxygenation index of ND group was significantly higher than the C group(P<0.05, Fig. 3 ) and N group (P<0.05, Fig. 3 ). Additionally, oxygen saturation was significantly higher in N and ND groups than in C group, at 1 hour postoperatively (Fig. 3 ). Among 80 patients, 37 (46.25%) experienced postoperative pulmonary complications, including 24 pulmonary atelectasis, 13 pneumonia, 11 respiratory failure and 4 pleural effusion for postoperative pulmonary complications. The postoperative pulmonary complications rate in the ND group was significantly lower than in the N and C groups (61.5% vs.51.8% vs. 25.9%, p = 0.026 * , Table 2 ). There was a significant difference in respiratory failure ( p = 0.044) between the three groups (Table 2 ). The ND group had significantly lower agitation scores than the C group in the PACU at 60 min postoperatively (Fig. 3 ). The movement pain scores in the ND group was lower than that of the C group in the PACU at the above time point (Fig. 3 ). Sufentanil consumptions at 24 hours postoperatively was significantly lower in the ND group than in the C group (P<0.01, Fig. 4 ). The time of first flatus was significantly earlier in ND group than in N group and C group (Fig. 4 ). The time of first defecation was significantly earlier in ND group than in N group (Fig. 4 ). Hospital stays in the ND group were significantly smaller than in the C and N groups (Fig. 4 ). Table 2 Various postoperative pulmonary complications in different groups. C group (n = 26) N group (n = 27) ND group (n = 27) p value Pulmonary Complications 16 14 7 0.026 * Pulmonary Atelectasis 9 10 5 0.453 Pneumonia 6 4 3 0.483 Respiratory Failure 7 3 1 0.044 * Pleural Effusion 1 4 0 0.066 Values are presented as n. Data were analyzed by chi-squared test. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001. Discussion This study shows that regional anesthesia combined with awake delayed extubation resulted in increased oxygenation index, decreased postoperative pulmonary complications and lung ultrasound scores after minimally invasive esophagectomy(MIE). In recent years, the MIE has been the most popular surgical procedure for the treatment of esophageal cancer, which can significantly reduce the surgical trauma pulmonary complications[ 13 , 14 ]. Despite improved perioperative management, the morbidity and mortality rates are still the highest after esophagectomy among all solid tumor surgeries. MIE involves dissection and trauma to large muscles, postoperative pain after MIE is still common and is a major factor affecting patients' recovery[ 15 ]. Adequate pain control can decrease PPCs, such as atelectasis or pneumonia and improve the quality of life for thoracic patients[ 16 ]. Regional analgesia techniques seem to be effective in postoperative management. Zhang et al. reported that continuous paravertebral block alleviated the pain of patients in the resting and active state for patients undergoing MIE, which enabled patients to get out of bed early, cough and sputum effectively, and decreased the incidence of pulmonary complications[ 7 ]. Postoperative pain in MIE mainly comes from the trauma of thoracic and abdomen, especially originated from the upper abdominal incision[ 15 ]. So, we applied SAPB for thoracic analgesia and used TAPB combined with RSB for abdominal analgesia. In this study, regional anesthesias produced a good postoperative analgesic effect and the analgesic consumption in the group N and ND was significantly lower than in the group C during the first 24 hours postoperatively. However, regional anesthesias failed to decrease the incidence of PPCs, nor improve oxygenation. This is consistent to a previous Cochrane review which included 14 studies and showed no significant difference in respiratory complications between groups[ 17 ]. Postoperative pulmonary complications mainly include atelectasis, pneumonia and respiratory failure, which usually cause to hypoxemia. Previous studies showed that perioperative interventions, including protective ventilation strategy[ 18 , 19 ], high-flow nasal cannula[ 20 ], epidural analgesia and regional anesthesias[ 21 ], respiratory physiotherapy[ 22 , 23 ], can reduce PPCs and improve oxygenation with thoracic and abdominal surgery. However, no high-quality evidence was found for interventions to reduce incidence of PPCs[ 24 , 25 ]. An intraoperative mechanical ventilation strategy with a higher level of PEEP and recruitment maneuvers did not reduce PPCs and protect postoperative spirometry in noncardiac surgery[ 26 – 28 ]. During general anesthesia, the intraoperative strategies demonstrated the effectiveness in improving intraoperative oxygenation and respiratory compliance, but failed to affect additional postoperative pulmonary outcomes[ 29 ]. A systematic review of respiratory physiotherapy in abdominal surgery concluded that physiotherapy provided no benefit[ 30 ]. A meta-analysis showed that most (11/12) trials reported no benefit of respiratory physiotherapy for PPC outcomes in abdominal and thoracic surgery[ 25 ]. In the fact, bronchial secretions are the main contributor to the PPCs and hypoxeamia. The MIE usually suffers long operation time and vast area of trauma that often involves neck, chest, and abdomen, which may impact the ability to manage secretions. Endotracheal intubation and mechanical ventilation can cause impairment in mucociliary clearance, which cause secretion retention, airway occlusion, atelectasis, and pneumonia[ 31 ]. Poor early postoperative laryngeal reflex protection and increased secretions from neck anastomosis also could increase the risk of aspiration. Though secretions in the proximal large airways are accessible to suctioning, airways beyond the 3rd generation are beyond the suction catheter’s reach[ 32 ]. Quintana et al. reported that respiratory physiotherapy, consisting of a set of techniques for mobilizing and eliminating pulmonary secretions, could minimize pulmonary complications in mechanically ventilated patients[ 13 ]. In our study, we adopted the respiratory physiotherapy technique during the awake period, in order to eliminate the secretions produced during the surgery. Our results showed that oxygenation index was significantly higher in group ND than in group C and N at 24 hours postoperatively, postoperative pulmonary complications were significantly lower in group ND than in group C and N. The additional volume of sputum aspirated during delayed extubation in group ND was 3.96 mL, which showed that awake delayed extubation was effective for sputum removal. The secretions elimination during awake delayed extubation help the re-expansion of atelactasis and allow adequate pulmonary ventilation, increase expiratory flow rates, then decrease pulmonary complications and improve oxygenation. Rose et al. also revealed that promoting cough and clearing secretions in critically-ill adults and children to enable removal of the endotracheal tube and breathing without the machine[ 33 ]. This trial also showed that the early out-of-bed activity, the time to first flatus and hospital stays of group ND were better than those in group C. Good analgesia effect and secretions elimination after operation in group ND reduced the frequency of coughing to expel sputum, alleviated postoperative pain and decreased the amount of remedial analgesics, enabled patients to get out of bed early, which further reduced the occurrence of pulmonary complications and shortened the hospital stays after operation. Hanada et al. showed that early mobilization reduced PPCs in patients undergoing video-assisted thoracoscopic surgery on the esophagus[ 34 ]. In this study, a lung protective ventilation strategy throughout the operation comprising limiting tidal volume, PEEP, and use of recruitment manoeuvres was selected. Michelet et al. found improved oxygenation index and a reduced duration of postoperative intermittent positive-pressure ventilation of approximately 1 hour, with a lung protective strategy during operation[ 35 ]. The agitation scores during PACU in the ND group were not significantly different from those of groups C and N, and the patients could cooperate the respiratory physiotherapy, which showed that the awake delayed extubation was a safe and feasible way of sputum excretion. Regional anesthesia analgesia, intraoperative dexmedetomidine, and postoperative tracheal surface anesthesia ensured patient tolerance to endotracheal tube during conscious extubation. As limitations of our study were mentioned that it was a single-centre study with a small sample size, and multicenter studies should be conducted in the future. In addition, the causes of postoperative pulmonary complications include multiple influencing factors. Only pain and delayed extubation were discussed in this study. Furthermore, our findings apply only to thoracolaparoscopic esophageal cancer surgery, not all thoracic surgeries. Conclusion This study demonstrated that regional anesthesia combined with awake delayed extubation can improve postoperative oxygenation index, reduce the incidence of PPCs, promote patients' recovery, and shorten hospital stays. It is recommended that future studies expand the sample size and generalize to other thoracic surgical procedures. Abbreviations PPCs Postoperative pulmonary complications SAM Serratus anterior plane block TAPB Transversus abdominis plane block RSB Rectus abdominis sheath block RAM Rectus abdominal muscle. TAM Transverse abdominis muscle. LA Local anesthetic. Declarations Acknowledgements We would like to thank Xiaopei Gao from the Chengdu Third People's Hospital, Sichuan Province for providing helpful advice and invaluable support regarding the experiments. Authors’ contributions JHY and YBZ generated the experimental hypothesis, designed the study, and wrote the manuscript; JHY, HYH and YLC generated and analyzed the experimental data; YHH, JL, YLC and SY have been involved in acquisition of data. Funding Funding: This work was supported by the University-level Scientific Research Development Program of North Sichuan Medical College [CBY21-QA48]; and the 2023 Scientific Research Development Plan of the Affiliated Hospital of North Sichuan Medical College [2023JC035]. Data Availability All data generated or analyzed during this study are included in this published article. Ethics approval and consent to participate This prospective, randomized, single-blinded trial protocol was approved by the Ethics Committee of the Affiliated Hospital of North Sichuan Medical College, No: 2022ER238-1. The study was registered at www.chictr.org.cn (identity number ChiCTR2200066726). Written informed consent and information release approvals were obtained from all patients before they participated. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Author details a Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China. b Department of Anesthesiology, The Sichuan Provincial Armed Police Corps Hospital, Leshan, China. c Department of General Surgery, Shanghai Fengxian District Central Hospital, Shanghai, 201499, China. References Yang YM, Hong P, Xu WW, He QY, Li B. Advances in targeted therapy for esophageal cancer. SIGNAL TRANSDUCT TAR. 2020;5(1):229. Kuwano H, Nishimura Y, Oyama T, Kato H, Kitagawa Y, Kusano M, Shimada H, Takiuchi H, Toh Y, Doki Y, et al. Guidelines for Diagnosis and Treatment of Carcinoma of the Esophagus April 2012 edited by the Japan Esophageal Society. ESOPHAGUS-TOKYO. 2015;12(1):1–30. 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An analysis of the factors contributing to a reduction in the incidence of pulmonary complications following an esophagectomy for esophageal cancer. LANGENBECK ARCH SURG. 2008;393(2):127–33. Fagevik OM, Hahn I, Nordgren S, Lonroth H, Lundholm K. Randomized controlled trial of prophylactic chest physiotherapy in major abdominal surgery. BRIT J SURG. 1997;84(11):1535–8. Singh P, Gossage J, Markar S, Pucher PH, Wickham A, Weblin J, Chidambaram S, Bull A, Pickering O, Mythen M, et al. Association of Upper Gastrointestinal Surgery of Great Britain and Ireland (AUGIS)/Perioperative Quality Initiative (POQI) consensus statement on intraoperative and postoperative interventions to reduce pulmonary complications after oesophagectomy. BRIT J SURG. 2022;109(11):1096–106. Odor PM, Bampoe S, Gilhooly D, Creagh-Brown B, Moonesinghe SR. Perioperative interventions for prevention of postoperative pulmonary complications: systematic review and meta-analysis. BMJ-BRIT MED J. 2020;368:m540. Hemmes SN, Gama DAM, Pelosi P, Schultz MJ. High versus low positive end-expiratory pressure during general anaesthesia for open abdominal surgery (PROVHILO trial): a multicentre randomised controlled trial. Lancet. 2014;384(9942):495–503. Bluth T, Serpa NA, Schultz MJ, Pelosi P, Gama DAM, Bluth T, Bobek I, Canet JC, Cinnella G, de Baerdemaeker L, et al. Effect of Intraoperative High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers vs Low PEEP on Postoperative Pulmonary Complications in Obese Patients: A Randomized Clinical Trial. JAMA-J AM MED ASSOC. 2019;321(23):2292–305. Treschan TA, Schaefer M, Kemper J, Bastin B, Kienbaum P, Pannen B, Hemmes SN, de Abreu MG, Pelosi P, Schultz MJ. Ventilation with high versus low peep levels during general anaesthesia for open abdominal surgery does not affect postoperative spirometry: A randomised clinical trial. EUR J ANAESTH. 2017;34(8):534–43. Lagier D, Zeng C, Fernandez-Bustamante A, Vidal MM. Perioperative Pulmonary Atelectasis: Part II. Clinical Implications. ANESTHESIOLOGY 2022, 136(1):206–236. Pasquina P, Tramer MR, Granier JM, Walder B. Respiratory physiotherapy to prevent pulmonary complications after abdominal surgery: a systematic review. Chest. 2006;130(6):1887–99. Konrad F, Schreiber T, Brecht-Kraus D, Georgieff M. Mucociliary transport in ICU patients. Chest. 1994;105(1):237–41. Volpe MS, Adams AB, Amato MB, Marini JJ. Ventilation patterns influence airway secretion movement. RESP CARE. 2008;53(10):1287–94. Rose L, Adhikari NK, Leasa D, Fergusson DA, McKim D. Cough augmentation techniques for extubation or weaning critically ill patients from mechanical ventilation. COCHRANE DB SYST REV. 2017;1(1):D11833. Hanada M, Kanetaka K, Hidaka S, Taniguchi K, Oikawa M, Sato S, Eguchi S, Kozu R. Effect of early mobilization on postoperative pulmonary complications in patients undergoing video-assisted thoracoscopic surgery on the esophagus. ESOPHAGUS-TOKYO. 2018;15(2):69–74. Michelet P, D'Journo XB, Roch A, Doddoli C, Marin V, Papazian L, Decamps I, Bregeon F, Thomas P, Auffray JP. Protective ventilation influences systemic inflammation after esophagectomy: a randomized controlled study. Anesthesiology. 2006;105(5):911–9. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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 Advisory Board 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-3850116","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":271374166,"identity":"63b7f82b-bad9-427d-a6c5-2cd8b6ce0714","order_by":0,"name":"Jinghao Yang","email":"","orcid":"","institution":"Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College","correspondingAuthor":false,"prefix":"","firstName":"Jinghao","middleName":"","lastName":"Yang","suffix":""},{"id":271374167,"identity":"82e18046-117f-48b3-be3f-039cd15667ec","order_by":1,"name":"Yihang He","email":"","orcid":"","institution":"Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College","correspondingAuthor":false,"prefix":"","firstName":"Yihang","middleName":"","lastName":"He","suffix":""},{"id":271374168,"identity":"a5dbe71c-88ce-4eea-8d76-0b283709578f","order_by":2,"name":"Jing Lin","email":"","orcid":"","institution":"Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College","correspondingAuthor":false,"prefix":"","firstName":"Jing","middleName":"","lastName":"Lin","suffix":""},{"id":271374169,"identity":"850fa122-5bce-41dc-a782-aa84592af3d2","order_by":3,"name":"Shan Yu","email":"","orcid":"","institution":"epartment of Anesthesiology, The Sichuan Provincial Armed Police Corps Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shan","middleName":"","lastName":"Yu","suffix":""},{"id":271374170,"identity":"78369c99-2bcc-45f7-91e1-4fcb30d139cb","order_by":4,"name":"Yongliang Chang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDUlEQVRIiWNgGAWjYLCCBwYgkgdE2MAYBEACQksajGFAQAsDXMthwloMjvcefpFQYJcn73724OeCX+cT+9nPHmAuqPiDW8uZc2kWCQbJxYZn8pKlZ/bdTpzZk5fAPOMMHltu5JgZJBgwJ26cwWMgzdtzO3HDgRwDZt42glrqQVqMf/P2nEvcf/4NUMs/vFqMHyQYHE6cL8FjJs3z40DiBgmQLQ24tUieOWMGDOTjiRt4csyseRuSjWfceGNwmOeYMU4tfMd7jD98+FOdOL/9jPFtnj92sv39OYaPeWrkcGpROMDAJgF24QEgwdjG4NgApA/gVA8E8g0MzB+gDCD4w2CPT/UoGAWjYBSMTAAAJINbFlPx348AAAAASUVORK5CYII=","orcid":"","institution":"Department of General Surgery, Shanghai Fengxian District Central Hospital","correspondingAuthor":true,"prefix":"","firstName":"Yongliang","middleName":"","lastName":"Chang","suffix":""},{"id":271374171,"identity":"51b53f70-b8e8-42d6-99d1-7f447f8fb42d","order_by":5,"name":"Youbo Zuo","email":"","orcid":"","institution":"Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College","correspondingAuthor":false,"prefix":"","firstName":"Youbo","middleName":"","lastName":"Zuo","suffix":""}],"badges":[],"createdAt":"2024-01-10 11:18:37","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3850116/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3850116/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":50877360,"identity":"432564ad-fb21-42d8-ba49-952f29c201d5","added_by":"auto","created_at":"2024-02-08 19:18:28","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":737694,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eUltrasound guided one puncture of RSB combined with TAPB.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ea\u003c/strong\u003e: ultrasound image showing the position of RSB combined TAPB.\u003cstrong\u003e b\u003c/strong\u003e: The ultrasound image of the spread of local anesthetic after local anesthetic injection. RAM, rectus abdominal muscle. TAM, transverse abdominis muscle. LA, local anesthetic. White arrows indicate the needle injection path.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3850116/v1/e2d0ed06d399f2affe2419d3.png"},{"id":50877361,"identity":"e22e5284-3b1a-4a8c-af56-b27a9f51edfa","added_by":"auto","created_at":"2024-02-08 19:18:28","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":321033,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCONSORT flow diagram for the trial.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3850116/v1/065e5350d83af08fab514878.png"},{"id":50877561,"identity":"5cc5df86-2d53-440a-b565-b135922c82c5","added_by":"auto","created_at":"2024-02-08 19:26:28","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":360644,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eOxygenation index, oxygen saturation, postoperative agitation score and postoperative pain score.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ea.\u003c/strong\u003e oxygenation index at three time points \u003cstrong\u003eb. \u003c/strong\u003eoxygenation saturation at three time points. \u003cstrong\u003ec.\u003c/strong\u003e agitation score within 60 min after surgery \u003cstrong\u003ed.\u003c/strong\u003e pain score at 60 min after extubation. * p\u0026lt;0.05, ** p\u0026lt;0.01, *** p\u0026lt;0.001, **** p\u0026lt;0.0001.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-3850116/v1/073833c98167ba267992af9a.png"},{"id":50877363,"identity":"9cbf1c24-d395-46fa-81bb-cbd414428172","added_by":"auto","created_at":"2024-02-08 19:18:28","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":112030,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDatas of the recovery and sufentanil consumptions.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ea. the time of first flatus in three groups \u003cstrong\u003eb.\u003c/strong\u003e the time of first defecation in three groups. \u003cstrong\u003ec. \u003c/strong\u003ehospital stays in three groups \u003cstrong\u003ed. \u003c/strong\u003esufentanil consumptions in three groups. * p\u0026lt;0.05, ** p\u0026lt;0.01, *** p\u0026lt;0.001, **** p\u0026lt;0.0001.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-3850116/v1/c241272a40eb95f78034ab0c.png"},{"id":64735914,"identity":"6327edde-af91-46dc-984d-118aa51de71c","added_by":"auto","created_at":"2024-09-18 07:50:38","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2518322,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3850116/v1/a83af436-ae9b-4e60-878e-9a6784baf59a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The effects of regional anesthesia combined with awake delayed extubation in patients undergoing esophageal cancer surgery: a single-blind randomized controlled trial","fulltext":[{"header":"Introduction","content":"\u003cp\u003eEsophageal cancer is one of the most common cancers worldwide, and surgical resection is one of the mainly clinical treatments for esophageal cancer[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. However, esophagectomy is associated with a high risk of postoperative morbidity and mortality, even with the development of minimally invasive endoscopic surgery and enhanced recovery programs[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Postoperative pulmonary complications (PPCs) are the most common complications after esophageal cancer surgery, with an incidence of up to 52%[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Atelectasis, pneumonia and respiratory failure are the main PPCs. These complications usually lead to hypoxaemia, an increase in hospital stays, intensive care unit admission rate and mortality, and decreased quality of life[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. As PPCs is a common cause of death following esophagectomy, improving postoperative oxygenation through decreased PPCs may further improve outcome.\u003c/p\u003e \u003cp\u003eIdeal postoperative analgesia contributes to the patient\u0026rsquo;s cough and expectoration, and would decrease complications such as hypoxemia, atelectasis, and pulmonary infection. Zhang et al. reported that continuous paravertebral block analgesia increased the satisfaction of postoperative analgesia and decreased the incidence of pulmonary complications for patients undergoing minimally invasive esophagectomy (MIE)[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, Brovman found that the regional anesthetic techniques were not associated with a lower incidence of pulmonary complications in lobectomy surgery[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe MIE usually suffers long operation time and vast area of trauma that often involves neck, chest, and abdomen. The trauma and esophageal anastomosis at the neck after MIE would increase secretions. The poor pharyngeal clearance of secretions could lead to laryngeal penetration and aspiration, and aspiration pneumonia[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] and the patients of MIE in the early stages of anesthesia recovery usually have no sufficient airway protection. Additionally, previous studies have reported severe secretion retention in patients with a tracheostomy tube than in those without. Good analgesia improves cough, however, postoperative sputum expectoration is still difficult.\u003c/p\u003e \u003cp\u003eIntraoperative lung recruitment, including lung protection ventilation strategy, have demonstrated the effectiveness in improving intraoperative oxygenation and early respiratory compliance, but not consistently translate into lower PPCs[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Strategies aiming to maintain lung recruitment in the post-anesthesia care unit, ICU or surgical ward may independently improve postoperative outcomes and be at least as valuable as intraoperative lung expansion interventions. Respiratory physiotherapy, consisting of a set of techniques for mobilizing and eliminating pulmonary secretions, could minimize pulmonary complications in mechanically ventilated patients[\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. However, few studies have analyzed the effectiveness of respiratory physiotherapy during extubation in prevention of hypoxemia for MIE patients. In the present study, we aimed to determine whether awake delayed extubation combined with respiratory physiotherapy improves postoperative oxygenation after esophagectomy.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eThis study was conducted as a single-blind and controlled trial. The inclusion criteria were patients diagnosed with esophageal cancer scheduled for minimally invasive esophagectomy, aged 18\u0026thinsp;\u0026minus;\u0026thinsp;79 years, physical status of I to III, according to the American Society of Anesthesiologists (ASA), and body mass index (BMI) between 18 and 30 kg / m\u003csup\u003e2\u003c/sup\u003e. Exclusion criteria were diaphragmatic dysfunction, severe immune system diseases, severe cardio-cerebrovascular disease allergy to local anesthetics, chronic opioid use prior to esophagectomy, renal failure, and inability to provide informed consent. Patients would be excited if the minimally invasive surgery converted to open surgery, operation time was more than 6 hours, or blood loss was more than 600 mL.\u003c/p\u003e \u003cp\u003e The study complied with the principles of the Declaration of Helsinki and was approved by the Ethics Committee of the Affiliated Hospital of North Sichuan Medical College, No: 2022ER238-1. The study was registered at \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ewww.chictr.org.cn\u003c/span\u003e\u003cspan address=\"http://www.chictr.org.cn\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (identity number ChiCTR2200066726). Written informed consent and information release approvals were obtained from all patients before they participated.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eRandomization and intervention\u003c/h2\u003e \u003cp\u003eNinety patients diagnosed with esophageal cancer undergoing elective thoracolaparoscopic esophagectomy were randomly divided into three groups in a 1:1:1 ratio: the controlled group (C group), the regional anesthesia group (N group), and the regional anesthesia combined with the awake extubation group (ND group). The randomization was conducted by randomization numbers generated by SPSS. Randomization results were kept in a sealed envelope and sent to an independent anesthesiologist who performed the regional anesthesia on the morning of surgery. Staff involved in data collection and analysis were blinded to group assignment. The anesthesiologists guiding the intervention, the participants and the coordinating researcher were not blinded for allocation.\u003c/p\u003e \u003cp\u003eThe patients in the C group didn\u0026rsquo;t receive any regional analgesic technique. The patients in the N group received ultrasound guided serratus anterior plane block (SAPB) with 30 mL of 0.33% ropivacaine, and the combination block of bilateral transversus abdominis plane block (TAPB) and rectus abdominis sheath block (RSB) with 10 mL of 0.25% ropivacaine in each plane by one puncture technique. Based on the regional blocks, the patients in the ND group received awake delayed extubation which means removing the endotracheal tube 30 min after waking up. All patients received postoperative patient controlled intravenous analgesia (PCIA) after surgery.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eAnesthesia and surgery\u003c/h2\u003e \u003cp\u003eAfter the patient entering the operation room, peripheral venous access was routinely established, pulse oximetry, electrocardiogram and noninvasive blood pressure were monitored, and radial artery cannulation were performed under local anesthesia to monitor invasive arterial pressure. Patients in groups N and ND received ultrasound-guided right serratus anterior plane block (SAPB) and bilateral rectus abdominis sheath block (RSB) combined transversus abdominis plane block (TAPB) under sedation and analgesia before anesthesia induction, while group C received no regional block. Anesthesia induction was performed with midazolam 0.03 mg / kg, sufentanil 0.3\u0026ndash;0.5 \u0026micro;g / kg, propofol 1.5-2 mg / kg and cisatracurium 0.15 mg / kg. Single-lumen endotracheal intubation was performed 3\u0026ndash;5 min after induction. Anesthesia was maintained with sevoflurane, intermittent intravenous injection of sufentanil and cisatracurium. The anesthetic dosage was continuously adjusted according to the mean arterial pressure within 20% of the baseline value. Intraoperative intravenous dexmedetomidine 0.5 \u0026micro;g / (kg*h) was pumped intravenously within 10 min, and then 0.4 \u0026micro;g / (kg*h) was continuously pumped intravenously until 30 min before closure of the incision. A lung protective ventilation strategy throughout the operation was applied, including limiting tidal volume (6\u0026ndash;8 mL / kg), positive end-expiratory pressure (5 cm H\u003csub\u003e2\u003c/sub\u003eO), maneuver recruitment and low fraction of inspired oxygen (40%-60%). The ventilatory frequency was adjusted to maintain the end-tidal carbon dioxide pressure between 35 and 45 mmHg.\u003c/p\u003e \u003cp\u003eEphedrine was administrated if the blood pressure was more than 20% below the baseline, and atropine was administered if the heart rate was lower than 50 bpm. At the end of surgery, postoperative analgesia was performed with a patient-controlled intravenous analgesia (PCIA) device. PCIA analgesia in all patients consisted of 150 ug sufentanil, 10 mg tropisetron with saline to 150 mL, a background infusion dose of 2 mL / h, and a bolus dose of 0.5 mL, with a 15-minute lockout time and a maximum of 10mL over 1 hour. When the VAS score was above 4, patients received intravenous tramadol (100 mg) as rescue analgesia. Neuromuscular blockade was reversed by neostigmine and glycopyrrolate when the return of spontaneous breathing appeared after surgery.\u003c/p\u003e \u003cp\u003eAll patients will undergo MIE with two-field lymphadenectomy, gastric conduit reconstruction, and an intrathoracic anastomosis. The operation was performed by conventional thoracolaparoscopic surgery. The procedure starts with an abdominal laparoscopic phase, which involves mobilization of the stomach, abdominal lymphadenectomy and gastric conduit construction. Then, the patient will be placed in (semi) prone position for thoracoscopy to mobilize the esophagus and perform a mediastinal lymphadenectomy. One of the trocarports is widened to a mini-thoracotomy for specimen extraction and when indicated, for the creation of the anastomosis. Gastrointestinal continuity is finally restored by a stapled or hand-sewn intrathoracic esophagogastric anastomosis. A maximum of one thoracic drain is placed on each side.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eUltrasound guided SAPB, TAPB, and RSB\u003c/h2\u003e \u003cp\u003eThe patients in the N and ND group received SAPB, and one-puncture technique of RSB combined with TAPB. The block was performed by a qualified anesthesiologist using ultrasound guidance (Mindray M9 Ultrasound System) and a high-frequency linear ultrasound probe. Firstly, the right SAPB was located between the fourth and fifth ribs of the midaxillary line, and 30 mL 0.33% ropivacaine was injected. Secondly, the probe was placed transversely in the midline of abdomen between the xiphoid process and the umbilicus, and moved outward along the costal margin, showing the rectus abdominis overlapping on the transverse abdominis (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea). The needle was inserted from inner side, and when the tip of the needle reached to the posterior rectus sheath, 0.5 mL saline was injected to adjust its position. Then, 10 mL of 0.25% ropivacaine was administered, and we can see local anesthetic spread inward. Then, the needle broke through the posterior rectus sheath, and 10 mL of 0.25% ropivacaine was injected, local anesthetic spreading outward. After the completion of the block, one membrane double capsule of ultrasound signs would be found (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb). The same block operation was performed on the opposite side.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eAwake delayed extubation and respiratory physiotherapy\u003c/h2\u003e \u003cp\u003eAt the end of the operation, 5 mL of 2% lidocaine was instilled through the endotracheal tube, and drain the air in the balloon at the same time, letting the local anesthetic distribute around the balloon, then the balloon was re-inflated. After the patient was fully awake, respiratory physiotherapy techniques that consist of lateral rotation, manual lung hyperinflation, tapotement and aspiration, were applied[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Let the patient in right tilt position associated with manually tapotement to facilitate the mobilization and drainage of the secretions away from the bottom of pulmonary, using the force of gravity. Then aspiration was administrated using a disposable sputum aspirator with sputum collector, the sputum volume was collected, and the tube was removed after 30 min.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eOxygenation and postoperative pulmonary complication\u003c/h2\u003e \u003cp\u003eArterial blood samples were collected before anesthesia (T0), at 1 hour after extubation (T1), and 24 hours after operation (T2) for blood gas analysis, oxygenation index was calculated based on arterial partial oxygen level (PaO\u003csub\u003e2\u003c/sub\u003e) and FIO\u003csub\u003e2\u003c/sub\u003e. The PPCs of the patients were defined according to the guidelines for European perioperative clinical outcome (EPCO) definitions, including pulmonary atelectasis, pneumonia, respiratory failure and pleural effusion. Patients were instructed preoperatively to use a visual analog scale (VAS) ranging from 0 cm (no pain) to 10 cm (most severe pain) and the PCIA pump device.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eSample size calculation\u003c/h2\u003e \u003cp\u003eThe sample size for the study was calculated based on a pilot study of 5 patients per group. The mean oxygenation index was 293\u0026thinsp;\u0026plusmn;\u0026thinsp;53 in the N group and 340\u0026thinsp;\u0026plusmn;\u0026thinsp;64 in the ND group. Assuming a two-sided type I error of 0.05 and type II error of 0.20 which eventually brings a power of 0.80 (1-β), 24 participants were needed per group. Considering possible drop-outs, we included at least 30 patients per group.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eSPSS 21.0 statistical software was used for data analysis. Continuous variables were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD) or median (interquartile range, IQR) and were compared using one-way analysis of variance (ANOVA). Categorical variables were described as frequencies (percentages), and comparisons were done by chi-square or Fisher's exact tests. Comparison of the three treatment groups of continuous variables satisfying normal distribution and chi-square was analyzed by ANOVA, and further two-by-two comparisons were made using the least squares test of variance. For variables that did not satisfy normal distribution and chi-square, the Kruskal-Wallis test was used to compare the three treatment groups, and further two-by-two comparisons were made using the Bonferroni correction.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 96 patients were selected in this study. Six patients were excluded. The remaining 90 patients were randomly assigned to group C, N, and ND (n\u0026thinsp;=\u0026thinsp;30). During the trial, 10 patients lost to follow-up, and 80 patients were included in the final analyses (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003ePre- and intraoperative data\u003c/h2\u003e \u003cp\u003eThere was no significant difference in demographic parameters, operation conditions, fluid and anesthetic administration among three groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Intraoperative sufentanil consumption was significantly smaller in the ND group than in the C group. The awake time of the patients was significantly smaller in the ND group than in the C group.\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\u003eThe demographic data and perioperative characteristics of the three groups\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 \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eC group (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN group (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eND group (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\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\u003eMale / Female (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23/3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.584\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (year)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65.77\u0026thinsp;\u0026plusmn;\u0026thinsp;6.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e67.86\u0026thinsp;\u0026plusmn;\u0026thinsp;6.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e63.37\u0026thinsp;\u0026plusmn;\u0026thinsp;7.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.399\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg / m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.42\u0026thinsp;\u0026plusmn;\u0026thinsp;2.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.67\u0026thinsp;\u0026plusmn;\u0026thinsp;2.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.84\u0026thinsp;\u0026plusmn;\u0026thinsp;2.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.599\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eASA (Ⅱ / Ⅲ)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21/5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.955\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eComorbidities, n (%)\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\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypertension (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5(19.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8(29.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3(11.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.234\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiabetes (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1(3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(3.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.593\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCOPD (n)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1(3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(7.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4(14.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.352\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnesthesia time (min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e286.00\u0026thinsp;\u0026plusmn;\u0026thinsp;62.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e283.81\u0026thinsp;\u0026plusmn;\u0026thinsp;57.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e276.59\u0026thinsp;\u0026plusmn;\u0026thinsp;40.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.801\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOperation time (min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e226.96\u0026thinsp;\u0026plusmn;\u0026thinsp;51.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e221.56\u0026thinsp;\u0026plusmn;\u0026thinsp;38.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e219.63\u0026thinsp;\u0026plusmn;\u0026thinsp;28.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.791\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntraoperative sufentanil consumption (\u0026micro;g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e67.12\u0026thinsp;\u0026plusmn;\u0026thinsp;14.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51.00\u0026thinsp;\u0026plusmn;\u0026thinsp;11.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e51.39\u0026thinsp;\u0026plusmn;\u0026thinsp;10.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.0001\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAwaking time(min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65.08\u0026thinsp;\u0026plusmn;\u0026thinsp;47.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.37\u0026thinsp;\u0026plusmn;\u0026thinsp;45.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e37.96\u0026thinsp;\u0026plusmn;\u0026thinsp;18.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.0023\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePacu time(min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e86.81\u0026thinsp;\u0026plusmn;\u0026thinsp;38.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e92.59\u0026thinsp;\u0026plusmn;\u0026thinsp;49.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.22\u0026thinsp;\u0026plusmn;\u0026thinsp;19.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.133\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eColloid volume (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1780.77\u0026thinsp;\u0026plusmn;\u0026thinsp;320.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1707.41\u0026thinsp;\u0026plusmn;\u0026thinsp;431.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1696.30\u0026thinsp;\u0026plusmn;\u0026thinsp;363.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.579\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCrystal volume (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e550.00\u0026thinsp;\u0026plusmn;\u0026thinsp;202.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e518.52\u0026thinsp;\u0026plusmn;\u0026thinsp;168.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e507.41\u0026thinsp;\u0026plusmn;\u0026thinsp;38.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.674\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e86.35\u0026thinsp;\u0026plusmn;\u0026thinsp;35.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e87.78\u0026thinsp;\u0026plusmn;\u0026thinsp;17.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100.74\u0026thinsp;\u0026plusmn;\u0026thinsp;54.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.334\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrine volume (mL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e521.15\u0026thinsp;\u0026plusmn;\u0026thinsp;294.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e485.19\u0026thinsp;\u0026plusmn;\u0026thinsp;328.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e464.81\u0026thinsp;\u0026plusmn;\u0026thinsp;176.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.751\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eadditional sputum volume(mL)\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\u003e3.96(1,15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eVariables are expressed as Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD, number or Median (interquartile range). BMI body mass index, ASA American Society of Anesthesiology. * p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, ** p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, *** p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, **** p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003ePostoperative data\u003c/h2\u003e \u003cp\u003eAt 1 hour and 24 hours postoperatively, the oxygenation index of ND group was significantly higher than the C group(P\u0026lt;0.05, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) and N group (P\u0026lt;0.05, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Additionally, oxygen saturation was significantly higher in N and ND groups than in C group, at 1 hour postoperatively (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Among 80 patients, 37 (46.25%) experienced postoperative pulmonary complications, including 24 pulmonary atelectasis, 13 pneumonia, 11 respiratory failure and 4 pleural effusion for postoperative pulmonary complications. The postoperative pulmonary complications rate in the ND group was significantly lower than in the N and C groups (61.5% vs.51.8% vs. 25.9%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.026\u003csup\u003e*\u003c/sup\u003e, Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). There was a significant difference in respiratory failure (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.044) between the three groups (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The ND group had significantly lower agitation scores than the C group in the PACU at 60 min postoperatively (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The movement pain scores in the ND group was lower than that of the C group in the PACU at the above time point (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Sufentanil consumptions at 24 hours postoperatively was significantly lower in the ND group than in the C group (P\u0026lt;0.01, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The time of first flatus was significantly earlier in ND group than in N group and C group (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The time of first defecation was significantly earlier in ND group than in N group (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Hospital stays in the ND group were significantly smaller than in the C and N groups (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \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\u003eVarious postoperative pulmonary complications in different groups.\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" 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\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eC group (n\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN group (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eND group (n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\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\u003ePulmonary Complications\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.026\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePulmonary Atelectasis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.453\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePneumonia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.483\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRespiratory Failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.044\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePleural Effusion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.066\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eValues are presented as n. Data were analyzed by chi-squared test. * p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, ** p\u0026thinsp;\u0026lt;\u0026thinsp;0.01, *** p\u0026thinsp;\u0026lt;\u0026thinsp;0.001, **** p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study shows that regional anesthesia combined with awake delayed extubation resulted in increased oxygenation index, decreased postoperative pulmonary complications and lung ultrasound scores after minimally invasive esophagectomy(MIE).\u003c/p\u003e \u003cp\u003eIn recent years, the MIE has been the most popular surgical procedure for the treatment of esophageal cancer, which can significantly reduce the surgical trauma pulmonary complications[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Despite improved perioperative management, the morbidity and mortality rates are still the highest after esophagectomy among all solid tumor surgeries. MIE involves dissection and trauma to large muscles, postoperative pain after MIE is still common and is a major factor affecting patients' recovery[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Adequate pain control can decrease PPCs, such as atelectasis or pneumonia and improve the quality of life for thoracic patients[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Regional analgesia techniques seem to be effective in postoperative management. Zhang et al. reported that continuous paravertebral block alleviated the pain of patients in the resting and active state for patients undergoing MIE, which enabled patients to get out of bed early, cough and sputum effectively, and decreased the incidence of pulmonary complications[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Postoperative pain in MIE mainly comes from the trauma of thoracic and abdomen, especially originated from the upper abdominal incision[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. So, we applied SAPB for thoracic analgesia and used TAPB combined with RSB for abdominal analgesia. In this study, regional anesthesias produced a good postoperative analgesic effect and the analgesic consumption in the group N and ND was significantly lower than in the group C during the first 24 hours postoperatively. However, regional anesthesias failed to decrease the incidence of PPCs, nor improve oxygenation. This is consistent to a previous Cochrane review which included 14 studies and showed no significant difference in respiratory complications between groups[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePostoperative pulmonary complications mainly include atelectasis, pneumonia and respiratory failure, which usually cause to hypoxemia. Previous studies showed that perioperative interventions, including protective ventilation strategy[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], high-flow nasal cannula[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], epidural analgesia and regional anesthesias[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], respiratory physiotherapy[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], can reduce PPCs and improve oxygenation with thoracic and abdominal surgery. However, no high-quality evidence was found for interventions to reduce incidence of PPCs[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. An intraoperative mechanical ventilation strategy with a higher level of PEEP and recruitment maneuvers did not reduce PPCs and protect postoperative spirometry in noncardiac surgery[\u003cspan additionalcitationids=\"CR27\" citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. During general anesthesia, the intraoperative strategies demonstrated the effectiveness in improving intraoperative oxygenation and respiratory compliance, but failed to affect additional postoperative pulmonary outcomes[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. A systematic review of respiratory physiotherapy in abdominal surgery concluded that physiotherapy provided no benefit[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. A meta-analysis showed that most (11/12) trials reported no benefit of respiratory physiotherapy for PPC outcomes in abdominal and thoracic surgery[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. In the fact, bronchial secretions are the main contributor to the PPCs and hypoxeamia. The MIE usually suffers long operation time and vast area of trauma that often involves neck, chest, and abdomen, which may impact the ability to manage secretions. Endotracheal intubation and mechanical ventilation can cause impairment in mucociliary clearance, which cause secretion retention, airway occlusion, atelectasis, and pneumonia[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Poor early postoperative laryngeal reflex protection and increased secretions from neck anastomosis also could increase the risk of aspiration.\u003c/p\u003e \u003cp\u003eThough secretions in the proximal large airways are accessible to suctioning, airways beyond the 3rd generation are beyond the suction catheter\u0026rsquo;s reach[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Quintana et al. reported that respiratory physiotherapy, consisting of a set of techniques for mobilizing and eliminating pulmonary secretions, could minimize pulmonary complications in mechanically ventilated patients[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In our study, we adopted the respiratory physiotherapy technique during the awake period, in order to eliminate the secretions produced during the surgery. Our results showed that oxygenation index was significantly higher in group ND than in group C and N at 24 hours postoperatively, postoperative pulmonary complications were significantly lower in group ND than in group C and N. The additional volume of sputum aspirated during delayed extubation in group ND was 3.96 mL, which showed that awake delayed extubation was effective for sputum removal. The secretions elimination during awake delayed extubation help the re-expansion of atelactasis and allow adequate pulmonary ventilation, increase expiratory flow rates, then decrease pulmonary complications and improve oxygenation. Rose et al. also revealed that promoting cough and clearing secretions in critically-ill adults and children to enable removal of the endotracheal tube and breathing without the machine[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis trial also showed that the early out-of-bed activity, the time to first flatus and hospital stays of group ND were better than those in group C. Good analgesia effect and secretions elimination after operation in group ND reduced the frequency of coughing to expel sputum, alleviated postoperative pain and decreased the amount of remedial analgesics, enabled patients to get out of bed early, which further reduced the occurrence of pulmonary complications and shortened the hospital stays after operation. Hanada et al. showed that early mobilization reduced PPCs in patients undergoing video-assisted thoracoscopic surgery on the esophagus[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this study, a lung protective ventilation strategy throughout the operation comprising limiting tidal volume, PEEP, and use of recruitment manoeuvres was selected. Michelet et al. found improved oxygenation index and a reduced duration of postoperative intermittent positive-pressure ventilation of approximately 1 hour, with a lung protective strategy during operation[\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. The agitation scores during PACU in the ND group were not significantly different from those of groups C and N, and the patients could cooperate the respiratory physiotherapy, which showed that the awake delayed extubation was a safe and feasible way of sputum excretion. Regional anesthesia analgesia, intraoperative dexmedetomidine, and postoperative tracheal surface anesthesia ensured patient tolerance to endotracheal tube during conscious extubation.\u003c/p\u003e \u003cp\u003eAs limitations of our study were mentioned that it was a single-centre study with a small sample size, and multicenter studies should be conducted in the future. In addition, the causes of postoperative pulmonary complications include multiple influencing factors. Only pain and delayed extubation were discussed in this study. Furthermore, our findings apply only to thoracolaparoscopic esophageal cancer surgery, not all thoracic surgeries.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study demonstrated that regional anesthesia combined with awake delayed extubation can improve postoperative oxygenation index, reduce the incidence of PPCs, promote patients' recovery, and shorten hospital stays. It is recommended that future studies expand the sample size and generalize to other thoracic surgical procedures.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003ePPCs \u0026nbsp; \u0026nbsp; \u0026nbsp; Postoperative pulmonary complications\u003c/p\u003e\n\u003cp\u003eSAM \u0026nbsp; \u0026nbsp; \u0026nbsp;Serratus anterior plane block \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTAPB \u0026nbsp; \u0026nbsp; Transversus abdominis plane block\u003c/p\u003e\n\u003cp\u003eRSB \u0026nbsp; \u0026nbsp; \u0026nbsp;Rectus abdominis sheath block\u003c/p\u003e\n\u003cp\u003eRAM \u0026nbsp; \u0026nbsp; Rectus abdominal muscle.\u003c/p\u003e\n\u003cp\u003eTAM \u0026nbsp; \u0026nbsp; Transverse abdominis muscle.\u003c/p\u003e\n\u003cp\u003eLA \u0026nbsp; \u0026nbsp; \u0026nbsp; Local anesthetic.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe would like to thank Xiaopei Gao from the Chengdu Third People\u0026apos;s Hospital, Sichuan Province for providing helpful advice and invaluable support regarding the experiments.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJHY and YBZ\u0026nbsp;generated the experimental hypothesis, designed the study, and wrote the manuscript; JHY, HYH and YLC generated and analyzed the experimental data; YHH, JL, YLC and SY\u0026nbsp;have been involved in acquisition of data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFunding: This work was supported by the University-level Scientific Research Development Program of North Sichuan Medical College [CBY21-QA48]; and the 2023 Scientific Research Development Plan of the Affiliated Hospital of North Sichuan Medical College [2023JC035].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included in this published article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis prospective, randomized, single-blinded trial protocol was\u0026nbsp;approved by the Ethics Committee of the Affiliated Hospital of North Sichuan Medical College, No: 2022ER238-1. The study was registered at www.chictr.org.cn (identity number ChiCTR2200066726). Written informed consent and information release approvals were obtained from all patients before they participated.\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 declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor details\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ea\u0026nbsp;\u003c/sup\u003eDepartment of Anesthesiology, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, China.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u0026nbsp;\u003c/sup\u003eDepartment of Anesthesiology, The Sichuan Provincial Armed Police Corps Hospital, Leshan, China.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u0026nbsp;\u003c/sup\u003eDepartment of General Surgery, Shanghai Fengxian District Central Hospital, Shanghai, 201499, China.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eYang YM, Hong P, Xu WW, He QY, Li B. 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Epidural analgesia and avoidance of blood transfusion are associated with reduced mortality in patients with postoperative pulmonary complications following thoracotomic esophagectomy: a retrospective cohort study of 335 patients. BMC ANESTHESIOL. 2019;19(1):162.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKlevebro F, Elliott JA, Slaman A, Vermeulen BD, Kamiya S, Rosman C, Gisbertz SS, Boshier PR, Reynolds JV, Rouvelas I, et al. Cardiorespiratory Comorbidity and Postoperative Complications following Esophagectomy: a European Multicenter Cohort Study. ANN SURG ONCOL. 2019;26(9):2864\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNozaki I, Mizusawa J, Kato K, Igaki H, Ito Y, Daiko H, Yano M, Udagawa H, Nakagawa S, Takagi M, et al. Impact of laparoscopy on the prevention of pulmonary complications after thoracoscopic esophagectomy using data from JCOG0502: a prospective multicenter study. 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Cough augmentation techniques for extubation or weaning critically ill patients from mechanical ventilation. COCHRANE DB SYST REV. 2017;1(1):D11833.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHanada M, Kanetaka K, Hidaka S, Taniguchi K, Oikawa M, Sato S, Eguchi S, Kozu R. Effect of early mobilization on postoperative pulmonary complications in patients undergoing video-assisted thoracoscopic surgery on the esophagus. ESOPHAGUS-TOKYO. 2018;15(2):69\u0026ndash;74.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMichelet P, D'Journo XB, Roch A, Doddoli C, Marin V, Papazian L, Decamps I, Bregeon F, Thomas P, Auffray JP. Protective ventilation influences systemic inflammation after esophagectomy: a randomized controlled study. Anesthesiology. 2006;105(5):911\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Oxygenation index, Awake delayed extubation, Regional anesthesia, Postoperative pulmonary complications, Esophagectomy","lastPublishedDoi":"10.21203/rs.3.rs-3850116/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3850116/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective:\u0026nbsp;\u003c/strong\u003ePostoperative pulmonary complications (PPCs) are the most frequent complications after esophagectomy, which usually causes to hypoxemia. The aim of this study is to evaluate whether regional anesthesia combined with awake delayed extubation improves postoperative oxygenation index after esophagectomy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u0026nbsp;Ninety patients diagnosed with esophageal cancer undergoing elective thoracolaparoscopic esophagectomy were randomized to three groups, control group (C group), regional anesthesia group (N group) and regional anesthesia combined with awake delayed extubation group (ND group). Regional anesthesia included serratus anterior plane block, transversus abdominis plane block, and rectus abdominis sheath block. Awake delayed extubation was defined as removing the endotracheal tube 30 min after waking up. The primary outcome was postoperative oxygenation index; secondary outcomes were the incidence of PPCs, analgesics consumption, postoperative pain scores, time to first flatus, time to first defecation, and hospital stays.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u0026nbsp;The oxygenation index of\u0026nbsp; ND group was significantly higher than the N group（\u003cem\u003eP\u003c/em\u003e＜0.05) and C group（\u003cem\u003eP\u003c/em\u003e\u0026lt;0.05) at 1 hour and 24 hours postoperatively. The incidence of PPCs was significantly lower in the ND group than in the N group and C group (61.5% vs.51.8% vs. 25.9%,\u0026nbsp;\u003cem\u003ep\u003c/em\u003e\u0026nbsp;= 0.026\u003csup\u003e*\u003c/sup\u003e).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e\u0026nbsp;Regional anesthesia combined with awake delayed extubation can significantly improve postoperative oxygenation index, reduce the incidence of PPCs, and promote patient recovery after thoracolaparoscopic esophageal cancer surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial registration:\u003c/strong\u003e The study was registered on Chinese Clinical Trial Registry, (ChiCTR2200066726) on 12/05/2023.\u003c/p\u003e","manuscriptTitle":"The effects of regional anesthesia combined with awake delayed extubation in patients undergoing esophageal cancer surgery: a single-blind randomized controlled trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-08 19:18:23","doi":"10.21203/rs.3.rs-3850116/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"61279fc5-1cee-4bfe-a1c9-814c10e048ba","owner":[],"postedDate":"February 8th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-09-18T07:42:30+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-08 19:18:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3850116","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3850116","identity":"rs-3850116","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}