Effect of Nalbuphine Combined with Ropivacaine on Analgesia and Prolactin after Cesarean Section

Effect of Nalbuphine Combined with Ropivacaine on Analgesia and Prolactin after Cesarean Section | 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 Effect of Nalbuphine Combined with Ropivacaine on Analgesia and Prolactin after Cesarean Section Xiaoxiao Wang, Min Huang, Huiling Li, Ying Qin This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8466755/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. To investigate the impact in women of nalbuphine and ropivacaine transverse abdominis plane block (TAPB) on pain relief and prolactin levels after cesarean section. Methods. Sixty pregnant women who underwent cesarean section and joint spinal-epidural anesthesia were categorized into two groups: Group A received 20ml of 0.5% ropivacaine and 10ml of normal saline injected into each side; Group B received 20ml of 0.5% ropivacaine, 1ml of nalbuphine, and 9ml of normal saline injected into each side. Serum prolactin (PRL) and cortisol levels were recorded before the operation (T0), and 2 (T1) and 24 (T4) hours after anesthesia. The time when colostrum was expressed was also recorded. The visual analogue scale (VAS) and Ramsay sedation scores were recorded at 2 (T1), 6 (T2), 12 (T3), and 24 hours (T4) after surgery. The incidence of postoperative nausea, vomiting, respiratory depression, itching, bradycardia, colostrum, and analgesic pump use were recorded. Results. Relative to group B, the prolactin levels pre-surgery (T0) showed no notable variance ( P > 0.05), although the prolactin levels at 2 (T1) and 24 hours (T4) post-surgery were considerably greater in group B than in group A ( P < 0.05). Colostrum production occurred sooner in group B than in group A ( P 0.05); however, the cortisol concentrations in group A at 2 (T1) and 24 hours (T4) post-surgery were considerably greater than those in group B ( P 0.05). In group B, the VAS pain levels were significantly lower than those in group A at T1–T4 ( P 0.05). Moreover, group B used an analgesic pump less frequently than group A ( P < 0.05). Conclusion. Nalbuphine combined with ropivacaine in transversus abdominis plane block may enhance maternal serum prolactin secretion, facilitating early lactation; It may also reduce serum cortisol levels, alleviating postoperative stress responses in cesarean section patients. Trial registration The trial was registered on November 04, 2025 at http://www.chictr.org.cn.(Clinical trial number：ChiCTR2500111707). Retrospectively registered. Nabuphine transverse abdominis plane block cesarean section prolactin nerve block Introduction The rate of cesarean section has been increasing annually in China [ 1 ]. Postoperative pain after cesarean section may inhibit prolactin secretion [ 2 ]. Prolactin secretion is regulated by hormones such as adrenaline and dopamine. In turn, post-cesarean section pain excites the sympathetic nerves and increases the release of dopamine and adrenaline, which inhibits the release of prolactin and leads to delayed lactation [ 3 ]. A decrease in prolactin levels is an independent risk factor for postpartum depression [ 4 ]. Good analgesia helps to shorten the time of colostrum administration, increase the amount of lactation, and provides a good foundation for the early establishment of exclusive breastfeeding [ 5 ]. Postoperative pain after cesarean section is mainly innervated by the anterior branch of T12–L1 nerves. Related to this, the transversus abdominis plane block can block the sensory nerves of T7–L1 and has no significant effect on the motor nerves. Therefore, transversus abdominis plane block can effectively block postoperative pain after cesarean section permitting early post-operative ambulation. Nalbuphine is an opioid that agonizes the κ receptor and selectively antagonizes the µ2 receptor, which can effectively reduce µ2 receptor-induced nausea and vomiting. Nalbuphine is more effective than sufentanil [ 6 , 7 ] in the treatment of uterine contraction pain. The amount of intravenous nalbuphine passing through the placenta to the fetus has been found to be very low [ 8 ]. Therefore, nalbuphine along with ropivacaine transversus abdominis plane block has high safety and efficacy in women undergoing cesarean section under combined lumbar and rigid anesthesia. This study explored the effects of the combination of nalbuphine and ropivacaine transversus abdominis plane block on postoperative analgesia and prolactin among women undergoing cesarean section. A secondary aim was to provide theoretical support and a new research direction for the development of a more effective postoperative analgesic regimen in situations of cesarean section. Information and methodology General information This study was conducted under the approval and supervision of the Medical Ethics Committee of Youjiang Medical university for nationalities. (Ethics Review No. 2022010401). Sixty women who underwent cesarean section surgery under lumbar rigid anesthesia at the Youjiang Medical university for nationalities. From January 2023 to December 2023 were selected. All enrolled individuals signed informed consent forms and were divided into group A (n = 30, ropivacaine trans abdominal plane block (TAPB) anesthesia) and group B (n = 30, nalbuphine combined with ropivacaine TAPB anesthesia) according to the randomized envelope lottery method. The inclusion criteria were as follows: (1) American Society of Anesthesia (ASA) grades I–II; (2) age 22–35 years; (3) gestational week 38–40 weeks; (4) singleton; and (5) body mass index (BMI) < 30 kg/m2. The exclusion criteria were as follows: (1) serious vital organ function abnormality, pregnancy comorbidities, or psychiatric diseases; (2) abnormal coagulation parameters; (3) skin puncture site (i.e., spinal skin, abdominal skin, spinal anesthesia); (4) anesthesia of the spine; and (5) anesthesia of the abdomen with nalbuphine and TAPB. Other exclusion criteria related to the anatomic region: spinal skin, transversus abdominis plane block - abdominal skin) infection and breakage; (6) a history of allergy to ropivacaine or nalbuphine; and (7) a history of long-term use of sedative and analgesic drugs. Methods Preparation for anesthesia In both groups, women were prohibited from drinking water for 2 hours and fasted for 8 hours before surgery. On entering the operating room, the study subjects were monitored for heart rate (HR), oxygen saturation (SPO2), blood pressure (BP), and respiratory rate (RR). Intraoperatively, subjects were observed for changes in vital signs and postoperative conditions. Open peripheral venous access to increase fluid volume as needed was also initiated. Combined lumbar and rigid anesthesia Both treatments groups were anesthetized with lumbar-rigid combined anesthesia. This consisted of 1.5 mL of 0.5% ropivacaine (ropivacaine hydrochloride injection [specification: 10 mL: 100 mg, production lot number: 231008CA, Jiangsu Hengrui Pharmaceutical Co., Ltd.]) injected into the subarachnoid space. The epidural catheter was left in place and fixed appropriately. The plane of anesthesia was adjusted so that it was below the T6 dermatome. Transversus abdominis plane block At the end of the surgery, a transversus abdominis plane block was initiated in the two cohort groups by trained personnel. The skin around the puncture point was sterilized, the perforated towel was spread, and the ultrasonic probe was placed vertically in the anterior axillary line between the costal margins and the iliac crest, identifying the structures of the skin and subcutaneous tissues, the external abdominal oblique and internal oblique muscles, the transversus abdominis plane, the transversus abdominis muscle, and other structures. Next, 22G puncture needles were inserted one by one using an in-patient technique, and the tip was pointed to reach the transverse abdominis plane. After reaching the plane of the transversus abdominis muscle and withdrawing no blood or gas, 0.5% ropivacaine 20 mL and saline 10 mL were injected into the plane on each side of group A subjects. Group B subjects received 0.5% ropivacaine 20 mL and 1 ml of 10 mg/mL nalbuphine (nalbuphine hydrochloride injection, specification: 1 mL:10 mg, Batch No. 23010661) into the plane of transversus abdominis muscle. Postoperative analgesic program Postoperatively, all individuals used the intravenous analgesic pump PCIA (drug formulation: sufentanil 2 μg/kg, sodium chloride injection diluted to 100 mL; parameter settings: background dose 2 mL/hour, single compression dose 2 mL, lock time 15 minutes; sufentanil citrate injection, specification: 1 mL:50 μg, production lot number: 31A090411, Yichang Renfu Pharmaceutical Co. Yichang Renfu Pharmaceutical Co.). Observational indicators (1) The general demographic information of the study subjects was recorded. (2) Four milliliters of venous blood was extracted from each individual at T0, T1, and T4. The plasma was centrifuged at 4000 r/min for 8 minutes and then stored in a refrigerator at –80°C. The cortisol level was measured by liquid chromatography tandem mass spectrometry, and the serum prolactin (PRL) level was measured by enzyme-linked immunosorbent assay. (3) The time of colostrum production was recorded. (4) The Ramsay sedation score and visual analogue scale (VAS) were recorded at T1, T2, T3, and T4 after surgery in both groups. The Ramsay sedation score was 0–6 points: 1, anxious and restless; 2, awake and quietly cooperative; 3, drowsy and responsive to instructions; 4, drowsy and responsive to stimuli; 5, drowsy and unresponsive to stimuli [9]. The VAS score was 0–10 points: 0 for no pain; 1–3 for mild pain; 4–6 for moderate pain; 7–10 for severe pain; and 10 for intolerable pain [10]. (5) The incidence of adverse reactions, including postoperative nausea and vomiting, skin itching, and respiratory depression, was recorded in both groups. (6) The number of postoperative analgesic pump presses was recorded for both groups. Statistical analysis SPSS 25.0 software was used to analyze the statistical data. Measurement data conformed to a normal distribution and was presented as the mean ± standard deviation (x ± s), and count data were tested using χ 2 test. Differences were considered statistically significant when P 0.05), (Table 1). Table 1 . Demographic datas Group A Group B t P ASA grading 1.23 ± 0.43 1.20 ± 0.41 0.31 0.760 Age (years) 30.47 ± 3.15 30.23 ± 3.08 0.29 0.770 BMI 28.51 ± 0.69 28.77 ± 0.84 –1.29 0.200 Length of surgery (hours) 1.51 ± 0.08 1.49 ± 0.05 1.15 0.250 Comparison of prolactin levels at different time points. At T0, there was no statistically significant difference between the prolactin levels of the individuals in groups A and B ( P > 0.05), whereas at T1 and T4, the prolactin levels of those in group B were significantly higher than those in group A ( P < 0.05), (Table 2). Table 2 . Comparison of prolactin levels at different time points Group Number of cases T0 (s/mL) T1 (s/mL) T4 (s/mL) Group A 30 263.76 ± 53.88 381.86 ± 75.75 460.33 ± 61.00 Group B 30 272.45 ± 58.09 615.10 ± 93.79* 603.48 ± 72.20* t –0.60 –10.60 –8.30 P 0.550 0.000 0.000 Comparison of maternal serum cortisol levels at different time points. At T0, there was no statistically significant difference in cortisol levels between groups A and B ( P > 0.05), whereas at T1 and T4, the cortisol levels in group A were significantly higher than those in group B ( P < 0.05) (Table 3). Table 3. Comparison of serum cortisol levels at different time points Group Number of cases T0 (nmol/L) T1 (nmol/L) T4 (nmol/L) Group A 30 285.95 ± 68.11 568.53 ± 73.11 932.55 ± 52.37 Group B 30 315.11 ± 56.56 399.90 ± 47.09* 592.15 ± 77.86* t –1.80 8.23 12.73 P 0.075 0.000 0.000 Comparison of the mean value of the time of postoperative colostrum secretion. In group B, postoperative colostrum was produced earlier than in group A ( P < 0.05) (Table 4). Table 4. Comparison of the mean values of postoperative colostrum secretion time . Group Number of cases Lactation time (hours) Group A 30 23.17±2.87 Group B 30 20.89±2.63* t 3.22 p 0.002 Comparison of maternal VAS scores at different time points. At T1, T2, T3, and T4, the VAS pain scores of the women in group B were lower than those in group A ( P < 0.05) (Table 5). Table 5. Comparison of maternal VAS scores at different time points . Group Number of cases T1 T2 T3 T4 Group A 30 2.30±0.70 2.77±0.68 4.57±0.50 3.83±0.70 Group B 30 1.43±0.50* 2.20±0.66* 3.80±0.66* 3.30±0.60* t 5.49 3.27 5.04 3.18 P 0.000 0.002 0.000 0.002 Comparison of Ramsay sedation scores at different time points. At T1, T2, T3, and T4 there was no statistically significant difference in the Ramsay sedation scores between the two groups ( P > 0.05) (Table 6). Table 6. Comparison of Ramsay sedation scores at different time points . Group Number of cases T1 T2 T3 T4 Group A 30 2.67±0.61 2.33±0.55 2.27±0.45 2.13±0.34 Group B 30 2.70±0.53 2.36±0.49 2.23±0.43 2.13±0.34 t -0.23 -0.25 0.29 0.00 P 0.822 0.804 0.770 1.000 Comparison of the incidence of postoperative adverse events. The difference in the incidence of postoperative adverse events (i.e., nausea and vomiting, skin itching, and respiratory depression) between the two groups was not statistically significant ( P > 0.05) (Table 7). Table 7 . Comparison of the incidence of postoperative adverse events. Groups Number of cases Nausea and vomiting Itchy skin Respiratory depression Incidence Group A 30 3 0 0 10 Group B 30 3 0 0 10 χ 2 0.00 P 1.000 Comparison of the number of postoperative analgesic pump compressions. The number of postoperative analgesic pump compressions used by the individuals in group B was lower than that in group A ( P < 0.05) (Table 8). Table 8. Comparison of the number of postoperative analgesic pump compressions . Groups Number of cases Number of analgesic pump presses (times) Group A 30 7.70±1.29 Group B 30 4.27±1.17* t 10.79 P 0.000 Discussion To reduce the dose of opioids after cesarean section, analgesic regimens such as transversus abdominis plane block, wound tube anesthesia, and single wound infiltration anesthesia can be applied. Transversus abdominis plane block, wound tube, and wound infiltration are the most recommended techniques[11]. Transversus abdominis plane block significantly reduced pain at rest and during exercise and lowered postoperative morphine use[12]. Additionally, general anesthesia combined with transversus abdominis plane block reduced perioperative opioid dependence in individuals that underwent surgery and reduced the stress response to surgery [13-17]. Nalbuphine agonizes the κ receptor and selectively antagonizes the μ2 receptor. Nalbuphine is fast-acting, effective in suppressing visceral pain, and can be safely used for postoperative analgesia after cesarean section. Prior studies found that nalbuphine content in maternal milk was low and did not affect breastfeeding after surgery [18]. Therefore, nalbuphine combined with ropivacaine transversus abdominis plane block is predicted to be effective and safe for intraoperative analgesia during cesarean section. In the present study, there was no statistically significant difference in the demographic data between the two groups. In addition, the difference in prolactin levels between groups A and B was not statistically significant at T0 ( P > 0.05), whereas the prolactin levels of group B were significantly higher than those of group A at T1 and T4 ( P < 0.05). This result, combined with the fact that the time of colostrum secretion of group B was earlier than that of group A, suggests that the combination of nalbuphine and ropivacaine transversus abdominis muscle planar blockade increased the secretion of serum prolactin in favor of the secretion of colostrum. The combination of ropivacaine transversus abdominis plane block and nalbuphine enhances the analgesic effect, reduces pain after cesarean section, decreases sympathetic excitation, and likely reduces the release of dopamine and adrenaline, all of which is favorable for prolactin secretion. Moreover, nalbuphine increased serum prolactin levels in healthy individuals [19]. Cortisol can reflect the degree of stress after surgery. At T0, the difference in cortisol levels between groups A and B were not statistically significant ( P > 0.05), whereas at T1 and T4, the cortisol levels in group A were significantly higher than those in group B ( P < 0.05). The results suggest that nalbuphine combined with ropivacaine transversus abdominis plane block reduces stress post-operatively, possibly by inhibiting the release of 5-hydroxytryptamine and SP and resulting in less serum cortisol [20]. It has also been shown that nalbuphine inhibits labor pain better than pethidine [21]. We showed that at all time points, the VAS pain scores of the group B subjects were lower than those of group A ( P < 0.05), and the number of postoperative analgesic pump compressions by group B was lower than that of group A ( P < 0.05). This suggests that nalbuphine combined with transversus abdominis muscle planar blockade with ropivacaine was more effective. In addition, there was no significant difference between the two groups in terms of the incidence of postoperative adverse effects and the Ramsay’s sedation score at all time points ( P > 0.05). Furthermore, the transversus abdominis muscle block combined with nalbuphine did not result in an excessive depth of anesthesia or increased the risk of adverse events. The antagonism of nalbuphine on the μ-receptor was found to reduce itching and respiratory depression [21,22]. This study has several limitations. First, the sample size was small and there were unaccounted factors that could confound the data and interpretation. Additionally, the study was not blinded or placebo controlled. Thus, bias in the researchers and study subjects may have impacted results. Further, the VAS and Ramsay sedation scores are subjective. Finally, prolactin and cortisol were measured only three times, and this would not capture dynamic changes in these hormones. Limitations of This Study This study still has certain limitations, which are reflected in the following aspects: 1. Small sample size: A total of 60 cases were enrolled in this study. Although this meets the basic statistical requirements, the limitation of the sample size still needs to be emphasized. A small sample size may affect the reliability of the results; especially when there are many influencing factors, the results may be biased and fail to fully reflect the real situation of the research objects. 2. Limitations of subjective scoring: Both the VAS (Visual Analogue Scale) and Ramsay Sedation Scale used in this study are subjective scoring methods. Despite detailed education on the scoring criteria during preoperative visits, differences in individual patients' subjective perceptions may still lead to scoring errors. Such subjectivity may affect the accurate evaluation of pain and sedation status. 3. Challenges of individualized dosage requirements: Factors such as maternal body weight and abdominal wall thickness may affect the drug diffusion effect. In addition, patients vary in pain sensitivity. Therefore, in clinical practice, it is necessary to dynamically adjust the drug volume (15-30ml per side) and concentration (0.2%-0.5%) to achieve the optimal analgesic effect. In conclusion, Nalbuphine combined with ropivacaine in transversus abdominis plane block may enhance maternal serum prolactin secretion, facilitating early lactation; It may also reduce serum cortisol levels, alleviating postoperative stress responses in cesarean section patients. Declarations Acknowledgments The authors thank all anesthesiologists, urologic surgeons and nurses who contributed to the study. Authors’ contributions Xiaoxiao Wang: Methodology, Investigation, Formal analysis, Writing – original draft. Min Huang: Conceptualization, Methodology. Huiling Li: Conceptualization, Methodology, Investigation. Ying Qin: Supervision, Project administration, Funding acquisition. Funding 1.Guangxi Medical and Health Appropriate Technology and Popularization and Application Project [grant numbers S2022137] 2.2025 Foshan Science and Technology Innovation Project [grant numbers 2520001002838]. Data availability The datasets used and analyzed in the current study are available from the corresponding author on reasonable request. Ethics approval and consent to participate This study protocol was reviewed and approved by the Medical Ethics Committee of Youjiang Medical university for nationalities. (Ethics Review No. 2022010401) .The trial was registered on November 04, 2025 at http://www.chictr.org.cn(Clinical trial number：ChiCTR2500111707), adhered to the CONSORT statement, and was conducted in accordance with the principles of the Declaration of Helsinki. Informed consent was obtained from all participants, who were informed of their rights, including the option to withdraw from the study at any stage. 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Effect of adding nalbuphine to intrathecal bupivacaine with morphine on postoperative nausea and vomiting and pruritus after elective cesarean delivery: a randomized double blinded study. Minerva Anestesiol. 2019 Mar;85(3):255-262. Zeng Z, Lu J, Shu C, Chen Y, Guo T, Wu QP, Yao SL, Yin P. A comparision of nalbuphine with morphine for analgesic effects and safety : meta-analysis of randomized controlled trials. Sci Rep. 2015 Jun 3;5:10927. 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. 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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-8466755","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":583692424,"identity":"fc952549-dda7-40b8-9ccf-39b2aa58b224","order_by":0,"name":"Xiaoxiao Wang","email":"","orcid":"","institution":"Youjiang Medical university for nationalities","correspondingAuthor":false,"prefix":"","firstName":"Xiaoxiao","middleName":"","lastName":"Wang","suffix":""},{"id":583692425,"identity":"7b8ef841-a39f-4af9-8514-b4104dd68ca2","order_by":1,"name":"Min Huang","email":"","orcid":"","institution":"School of Medicine, the Sixth Affiliated Hospital of South China University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Min","middleName":"","lastName":"Huang","suffix":""},{"id":583692426,"identity":"acdaddc2-d0fc-48e7-b5b0-32d64c493d57","order_by":2,"name":"Huiling Li","email":"","orcid":"","institution":"Youjiang Medical university for nationalities","correspondingAuthor":false,"prefix":"","firstName":"Huiling","middleName":"","lastName":"Li","suffix":""},{"id":583692427,"identity":"9e43426a-cc67-4f07-897e-6d45b187139f","order_by":3,"name":"Ying Qin","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA50lEQVRIiWNgGAWjYFAC5sMPJCpq6vnlHx848OEHUVrY0gwszhxLkGxISzw4s4coLTwKEpVtzAkGB3KMD3OwEaGB70YOg8ENNrY8gwNnPhxm4GGQ5xc7gF+L5I3cAw9n8MgUSx7s3XC4wILBcObsBPxaDG7kJRhLSLAx9h3m3XB4Bg9DgsFtglpyDKT/GDAzNhzjeXCYh41ILRISCcyJE87wMBCnRfLMszQDiQPHjCVnsBkAA1mCsF/4jicffiD5r0aOX4L58YcPP2zk+aUJaGG4gKpAgoByEDh/gAhFo2AUjIJRMLIBAATaTXPE5vw2AAAAAElFTkSuQmCC","orcid":"","institution":"School of Medicine, the Sixth Affiliated Hospital of South China University of Technology","correspondingAuthor":true,"prefix":"","firstName":"Ying","middleName":"","lastName":"Qin","suffix":""}],"badges":[],"createdAt":"2025-12-28 15:53:29","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8466755/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8466755/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103292989,"identity":"0edc884a-4b73-49de-b376-958391f9620b","added_by":"auto","created_at":"2026-02-24 06:42:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":847418,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8466755/v1/71ba0c10-88d0-4fdb-ab21-3ccf8bb91e7f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of Nalbuphine Combined with Ropivacaine on Analgesia and Prolactin after Cesarean Section","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe rate of cesarean section has been increasing annually in China [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Postoperative pain after cesarean section may inhibit prolactin secretion [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Prolactin secretion is regulated by hormones such as adrenaline and dopamine. In turn, post-cesarean section pain excites the sympathetic nerves and increases the release of dopamine and adrenaline, which inhibits the release of prolactin and leads to delayed lactation [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. A decrease in prolactin levels is an independent risk factor for postpartum depression [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Good analgesia helps to shorten the time of colostrum administration, increase the amount of lactation, and provides a good foundation for the early establishment of exclusive breastfeeding [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Postoperative pain after cesarean section is mainly innervated by the anterior branch of T12\u0026ndash;L1 nerves. Related to this, the transversus abdominis plane block can block the sensory nerves of T7\u0026ndash;L1 and has no significant effect on the motor nerves. Therefore, transversus abdominis plane block can effectively block postoperative pain after cesarean section permitting early post-operative ambulation. Nalbuphine is an opioid that agonizes the κ receptor and selectively antagonizes the \u0026micro;2 receptor, which can effectively reduce \u0026micro;2 receptor-induced nausea and vomiting. Nalbuphine is more effective than sufentanil [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] in the treatment of uterine contraction pain. The amount of intravenous nalbuphine passing through the placenta to the fetus has been found to be very low [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Therefore, nalbuphine along with ropivacaine transversus abdominis plane block has high safety and efficacy in women undergoing cesarean section under combined lumbar and rigid anesthesia. This study explored the effects of the combination of nalbuphine and ropivacaine transversus abdominis plane block on postoperative analgesia and prolactin among women undergoing cesarean section. A secondary aim was to provide theoretical support and a new research direction for the development of a more effective postoperative analgesic regimen in situations of cesarean section.\u003c/p\u003e"},{"header":"Information and methodology","content":"\u003cp\u003e\u003cstrong\u003eGeneral information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted under the approval and supervision of the Medical Ethics Committee of Youjiang Medical university for nationalities. (Ethics Review No. 2022010401). Sixty women who underwent cesarean section surgery under lumbar rigid anesthesia at the Youjiang Medical university for nationalities. From January 2023 to December 2023 were selected. All enrolled individuals signed informed consent forms and were divided into group A (n = 30, ropivacaine trans abdominal plane block (TAPB) anesthesia) and group B (n = 30, nalbuphine combined with ropivacaine TAPB anesthesia) according to the randomized envelope lottery method. The inclusion criteria were as follows: (1) American Society of Anesthesia (ASA) grades I\u0026ndash;II; (2) age 22\u0026ndash;35 years; (3) gestational week 38\u0026ndash;40 weeks; (4) singleton; and (5) body mass index (BMI) \u0026lt; 30 kg/m2. The exclusion criteria were as follows: (1) serious vital organ function abnormality, pregnancy comorbidities, or psychiatric diseases; (2) abnormal coagulation parameters; (3) skin puncture site (i.e., spinal skin, abdominal skin, spinal anesthesia); (4) anesthesia of the spine; and (5) anesthesia of the abdomen with nalbuphine and TAPB. Other exclusion criteria related to the anatomic region: spinal skin, transversus abdominis plane block - abdominal skin) infection and breakage; (6) a history of allergy to ropivacaine or nalbuphine; and (7) a history of long-term use of sedative and analgesic drugs.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePreparation for anesthesia\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn both groups, women were prohibited from drinking water for 2 hours and fasted for 8 hours before surgery. On entering the operating room, the study subjects were monitored for heart rate (HR), oxygen saturation (SPO2), blood pressure (BP), and respiratory rate (RR). Intraoperatively, subjects were observed for changes in vital signs and postoperative conditions. Open peripheral venous access to increase fluid volume as needed was also initiated.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCombined lumbar and rigid anesthesia\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBoth treatments groups were anesthetized with lumbar-rigid combined anesthesia. This consisted of 1.5 mL of 0.5% ropivacaine (ropivacaine hydrochloride injection [specification: 10 mL: 100 mg, production lot number: 231008CA, Jiangsu Hengrui Pharmaceutical Co., Ltd.]) injected into the subarachnoid space. The epidural catheter was left in place and fixed appropriately. The plane of anesthesia was adjusted so that it was below the T6 dermatome.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTransversus abdominis plane block\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt the end of the surgery, a transversus abdominis plane block was initiated in the two cohort groups by trained personnel. The skin around the puncture point was sterilized, the perforated towel was spread, and the ultrasonic probe was placed vertically in the anterior axillary line between the costal margins and the iliac crest, identifying the structures of the skin and subcutaneous tissues, the external abdominal oblique and internal oblique muscles, the transversus abdominis plane, the transversus abdominis muscle, and other structures. Next, 22G puncture needles were inserted one by one using an in-patient technique, and the tip was pointed to reach the transverse abdominis plane. After reaching the plane of the transversus abdominis muscle and withdrawing no blood or gas, 0.5% ropivacaine 20 mL and saline 10 mL were injected into the plane on each side of group A subjects. Group B subjects received 0.5% ropivacaine 20 mL and 1 ml of 10 mg/mL nalbuphine (nalbuphine hydrochloride injection, specification: 1 mL:10 mg, Batch No. 23010661) into the plane of transversus abdominis muscle.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePostoperative analgesic program\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePostoperatively, all individuals used the intravenous analgesic pump PCIA (drug formulation: sufentanil 2 \u0026mu;g/kg, sodium chloride injection diluted to 100 mL; parameter settings: background dose 2 mL/hour, single compression dose 2 mL, lock time 15 minutes; sufentanil citrate injection, specification: 1 mL:50 \u0026mu;g, production lot number: 31A090411, Yichang Renfu Pharmaceutical Co. Yichang Renfu Pharmaceutical Co.).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObservational indicators\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e(1) The general demographic information of the study subjects was recorded.\u003c/p\u003e\n\u003cp\u003e(2) Four milliliters of venous blood was extracted from each individual at T0, T1, and T4. The plasma was centrifuged at 4000 r/min for 8 minutes and then stored in a refrigerator at \u0026ndash;80\u0026deg;C. The cortisol level was measured by liquid chromatography tandem mass spectrometry, and the serum prolactin (PRL) level was measured by enzyme-linked immunosorbent assay.\u003c/p\u003e\n\u003cp\u003e(3) The time of colostrum production was recorded.\u003c/p\u003e\n\u003cp\u003e(4) The Ramsay sedation score and visual analogue scale (VAS) were recorded at T1, T2, T3, and T4 after surgery in both groups. The Ramsay sedation score was 0\u0026ndash;6 points: 1, anxious and restless; 2, awake and quietly cooperative; 3, drowsy and responsive to instructions; 4, drowsy and responsive to stimuli; 5, drowsy and unresponsive to stimuli [9]. The VAS score was 0\u0026ndash;10 points: 0 for no pain; 1\u0026ndash;3 for mild pain; 4\u0026ndash;6 for moderate pain; 7\u0026ndash;10 for severe pain; and 10 for intolerable pain [10].\u003c/p\u003e\n\u003cp\u003e(5) The incidence of adverse reactions, including postoperative nausea and vomiting, skin itching, and respiratory depression, was recorded in both groups.\u003c/p\u003e\n\u003cp\u003e(6) The number of postoperative analgesic pump presses was recorded for both groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSPSS 25.0 software was used to analyze the statistical data. Measurement data conformed to a normal distribution and was presented as the mean \u0026plusmn; standard deviation (x \u0026plusmn; s), and count data were tested using \u0026chi;\u003cem\u003e\u003csup\u003e2\u0026nbsp;\u003c/sup\u003e\u003c/em\u003etest. Differences were considered statistically significant when\u003cem\u003e\u0026nbsp;P\u003c/em\u003e \u0026lt; 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eDemographic data.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe general information (i.e., ASA classification, age, BMI, and duration of surgery) was not significantly different between the two groups (\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026gt; 0.05), (Table 1).\u003c/p\u003e\n\u003cp\u003eTable 1\u003cstrong\u003e. Demographic\u003c/strong\u003e datas\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"563\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 122px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eASA grading\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 122px;\"\u003e\n \u003cp\u003e1.23 \u0026plusmn; 0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e1.20 \u0026plusmn; 0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e0.760\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 122px;\"\u003e\n \u003cp\u003e30.47 \u0026plusmn; 3.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e30.23 \u0026plusmn; 3.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e0.770\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 122px;\"\u003e\n \u003cp\u003e28.51 \u0026plusmn; 0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e28.77 \u0026plusmn; 0.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e\u0026ndash;1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e0.200\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eLength of surgery (hours)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 122px;\"\u003e\n \u003cp\u003e1.51 \u0026plusmn; 0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e1.49 \u0026plusmn; 0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 87px;\"\u003e\n \u003cp\u003e1.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e0.250\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of prolactin levels at different time points.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt T0, there was no statistically significant difference between the prolactin levels of the individuals in groups A and B (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05), whereas at T1 and T4, the prolactin levels of those in group B were significantly higher than those in group A (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05), (Table 2).\u003c/p\u003e\n\u003cp\u003eTable 2\u003cstrong\u003e.\u003c/strong\u003e Comparison of prolactin levels at different time points\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"579\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 71px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 139px;\"\u003e\n \u003cp\u003eT0 (s/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 150px;\"\u003e\n \u003cp\u003eT1 (s/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003eT4 (s/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 71px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 139px;\"\u003e\n \u003cp\u003e263.76 \u0026plusmn; 53.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 150px;\"\u003e\n \u003cp\u003e381.86 \u0026plusmn; 75.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e460.33 \u0026plusmn; 61.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 71px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 139px;\"\u003e\n \u003cp\u003e272.45 \u0026plusmn; 58.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 150px;\"\u003e\n \u003cp\u003e615.10 \u0026plusmn; 93.79*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e603.48 \u0026plusmn; 72.20*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 71px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 139px;\"\u003e\n \u003cp\u003e\u0026ndash;0.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 150px;\"\u003e\n \u003cp\u003e\u0026ndash;10.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026ndash;8.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 68px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 71px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 139px;\"\u003e\n \u003cp\u003e0.550\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 150px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of maternal serum cortisol levels at different time points.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt T0, there was no statistically significant difference in cortisol levels between groups A and B (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05), whereas at T1 and T4, the cortisol levels in group A were significantly higher than those in group B (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) (Table 3).\u003c/p\u003e\n\u003cp\u003eTable 3. Comparison of serum cortisol levels at different time points\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"562\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003eT0 (nmol/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 138px;\"\u003e\n \u003cp\u003eT1 (nmol/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003eT4 (nmol/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e285.95 \u0026plusmn; 68.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 138px;\"\u003e\n \u003cp\u003e568.53 \u0026plusmn; 73.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e932.55 \u0026plusmn; 52.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e315.11 \u0026plusmn; 56.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 138px;\"\u003e\n \u003cp\u003e399.90 \u0026plusmn; 47.09*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e592.15 \u0026plusmn; 77.86*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026ndash;1.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 138px;\"\u003e\n \u003cp\u003e8.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e12.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 119px;\"\u003e\n \u003cp\u003e0.075\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 138px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of the mean value of the time of postoperative colostrum secretion.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn group B, postoperative colostrum was produced earlier than in group A (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) (Table 4).\u003c/p\u003e\n\u003cp\u003eTable 4. Comparison of the\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003emean values of postoperative colostrum secretion time\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"562\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 213px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 253px;\"\u003e\n \u003cp\u003eLactation time (hours)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 213px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 253px;\"\u003e\n \u003cp\u003e23.17\u0026plusmn;2.87\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 213px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 253px;\"\u003e\n \u003cp\u003e20.89\u0026plusmn;2.63*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003et\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 213px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 253px;\"\u003e\n \u003cp\u003e3.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 213px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 253px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of maternal VAS scores at different time points.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt T1, T2, T3, and T4, the VAS pain scores of the women in group B were lower than those in group A (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) (Table 5).\u003c/p\u003e\n\u003cp\u003eTable 5. Comparison of maternal VAS scores at different time points\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"561\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eT2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eT3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003eT4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e2.30\u0026plusmn;0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e2.77\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e4.57\u0026plusmn;0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e3.83\u0026plusmn;0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e1.43\u0026plusmn;0.50*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e2.20\u0026plusmn;0.66*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e3.80\u0026plusmn;0.66*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e3.30\u0026plusmn;0.60*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e5.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e3.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e5.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e3.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of Ramsay sedation scores at different time points.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAt T1, T2, T3, and T4 there was no statistically significant difference in the Ramsay sedation scores between the two groups (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05) (Table 6).\u003c/p\u003e\n\u003cp\u003eTable 6. Comparison of \u003cstrong\u003eRamsay\u003c/strong\u003e sedation \u003cstrong\u003escores\u003c/strong\u003e at different time points\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"561\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroup\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003eT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 115px;\"\u003e\n \u003cp\u003eT2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003eT3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eT4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e2.67\u0026plusmn;0.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 115px;\"\u003e\n \u003cp\u003e2.33\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003e2.27\u0026plusmn;0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e2.13\u0026plusmn;0.34\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e2.70\u0026plusmn;0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 115px;\"\u003e\n \u003cp\u003e2.36\u0026plusmn;0.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003e2.23\u0026plusmn;0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e2.13\u0026plusmn;0.34\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e-0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 115px;\"\u003e\n \u003cp\u003e-0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003e0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 99px;\"\u003e\n \u003cp\u003e0.822\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 115px;\"\u003e\n \u003cp\u003e0.804\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003e0.770\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of the incidence of postoperative adverse events.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe difference in the incidence of postoperative adverse events (i.e., nausea and vomiting, skin itching, and respiratory depression) between the two groups was not statistically significant (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05) (Table 7).\u003c/p\u003e\n\u003cp\u003eTable 7\u003cstrong\u003e.\u003c/strong\u003e Comparison of the incidence of postoperative adverse \u003cstrong\u003eevents.\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 66px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003eNausea and vomiting\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 116px;\"\u003e\n \u003cp\u003eItchy skin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003eRespiratory depression\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 105px;\"\u003e\n \u003cp\u003eIncidence\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 116px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 105px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 116px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 105px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026chi;\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 116px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 105px;\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 116px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 105px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eComparison of the number of postoperative analgesic pump compressions.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe number of postoperative analgesic pump compressions used by the individuals in group B was lower than that in group A (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) (Table 8).\u003c/p\u003e\n\u003cp\u003eTable 8. Comparison of the number of postoperative analgesic pump compressions\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"563\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroups\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 212px;\"\u003e\n \u003cp\u003eNumber of cases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 255px;\"\u003e\n \u003cp\u003eNumber of analgesic pump presses (times)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroup A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 212px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 255px;\"\u003e\n \u003cp\u003e7.70\u0026plusmn;1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003eGroup B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 212px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 255px;\"\u003e\n \u003cp\u003e4.27\u0026plusmn;1.17*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 212px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 255px;\"\u003e\n \u003cp\u003e10.79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 212px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 255px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eTo reduce the dose of opioids after cesarean section, analgesic regimens such as transversus abdominis plane block, wound tube anesthesia, and single wound infiltration anesthesia can be applied. Transversus abdominis plane block, wound tube, and wound infiltration are the most recommended techniques[11]. Transversus abdominis plane block significantly reduced pain at rest and during exercise and lowered postoperative morphine use[12]. Additionally, general anesthesia combined with transversus abdominis plane block reduced perioperative opioid dependence in individuals that underwent surgery and reduced the stress response to surgery [13-17]. Nalbuphine agonizes the \u0026kappa; receptor and selectively antagonizes the \u0026mu;2 receptor. Nalbuphine is fast-acting, effective in suppressing visceral pain, and can be safely used for postoperative analgesia after cesarean section. Prior studies found that nalbuphine content in maternal milk was low and did not affect breastfeeding after surgery [18]. Therefore, nalbuphine combined with ropivacaine transversus abdominis plane block is predicted to be effective and safe for intraoperative analgesia during cesarean section.\u003c/p\u003e\n\u003cp\u003eIn the present study, there was no statistically significant difference in the demographic data between the two groups. In addition, the difference in prolactin levels between groups A and B was not statistically significant at T0 (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05), whereas the prolactin levels of group B were significantly higher than those of group A at T1 and T4 (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). This result, combined with the fact that the time of colostrum secretion of group B was earlier than that of group A, suggests that the combination of nalbuphine and ropivacaine transversus abdominis muscle planar blockade increased the secretion of serum prolactin in favor of the secretion of colostrum. The combination of ropivacaine transversus abdominis plane block and nalbuphine enhances the analgesic effect, reduces pain after cesarean section, decreases sympathetic excitation, and likely reduces the release of dopamine and adrenaline, all of which is favorable for prolactin secretion. Moreover, nalbuphine increased serum prolactin levels in healthy individuals [19]. Cortisol can reflect the degree of stress after surgery. At T0, the difference in cortisol levels between groups A and B were not statistically significant (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05), whereas at T1 and T4, the cortisol levels in group A were significantly higher than those in group B (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). The results suggest that nalbuphine combined with ropivacaine transversus abdominis plane block reduces stress post-operatively, possibly by inhibiting the release of 5-hydroxytryptamine and SP and resulting in less serum cortisol [20]. It has also been shown that nalbuphine inhibits labor pain better than pethidine [21]. We showed that at all time points, the VAS pain scores of the group B subjects were lower than those of group A (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05), and the number of postoperative analgesic pump compressions by group B was lower than that of group A (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). This suggests that nalbuphine combined with transversus abdominis muscle planar blockade with ropivacaine was more effective. In addition, there was no significant difference between the two groups in terms of the incidence of postoperative adverse effects and the Ramsay\u0026rsquo;s sedation score at all time points (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05). Furthermore, the transversus abdominis muscle block combined with nalbuphine did not result in an excessive depth of anesthesia or increased the risk of adverse events. The antagonism of nalbuphine on the \u0026mu;-receptor was found to reduce itching and respiratory depression [21,22].\u003c/p\u003e\n\u003cp\u003eThis study has several limitations. First, the sample size was small and there were unaccounted factors that could confound the data and interpretation. Additionally, the study was not blinded or placebo controlled. Thus, bias in the researchers and study subjects may have impacted results.\u003c/p\u003e\n\u003cp\u003eFurther, the VAS and Ramsay sedation scores are subjective. Finally, prolactin and cortisol were measured only three times, and this would not capture dynamic changes in these hormones.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations of This Study\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study still has certain limitations, which are reflected in the following aspects:\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;1. Small sample size: A total of 60 cases were enrolled in this study. Although this meets the basic statistical requirements, the limitation of the sample size still needs to be emphasized. A small sample size may affect the reliability of the results; especially when there are many influencing factors, the results may be biased and fail to fully reflect the real situation of the research objects.\u003c/p\u003e\n\u003cp\u003e2.\u0026nbsp;Limitations of subjective scoring: Both the VAS (Visual Analogue Scale) and Ramsay Sedation Scale used in this study are subjective scoring methods. Despite detailed education on the scoring criteria during preoperative visits, differences in individual patients\u0026apos; subjective perceptions may still lead to scoring errors. Such subjectivity may affect the accurate evaluation of pain and sedation status.\u003c/p\u003e\n\u003cp\u003e3. Challenges of individualized dosage requirements: Factors such as maternal body weight and abdominal wall thickness may affect the drug diffusion effect. In addition, patients vary in pain sensitivity. Therefore, in clinical practice, it is necessary to dynamically adjust the drug volume (15-30ml per side) and concentration (0.2%-0.5%) to achieve the optimal analgesic effect.\u003c/p\u003e\n\u003cp\u003eIn conclusion, Nalbuphine combined with ropivacaine in transversus abdominis plane block may enhance maternal serum prolactin secretion, facilitating early lactation; It may also reduce serum cortisol levels, alleviating postoperative stress responses in cesarean section patients.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank all anesthesiologists, urologic surgeons and nurses who contributed to the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eXiaoxiao Wang:\u0026nbsp;\u003c/strong\u003eMethodology, Investigation, Formal analysis, Writing \u0026ndash; original draft. \u003cstrong\u003eMin Huang:\u003c/strong\u003e Conceptualization, Methodology. \u003cstrong\u003eHuiling Li:\u003c/strong\u003e Conceptualization, Methodology, Investigation. \u003cstrong\u003eYing Qin:\u003c/strong\u003e Supervision, Project administration, Funding acquisition.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.Guangxi Medical and Health Appropriate Technology and Popularization and Application Project [grant numbers S2022137]\u003c/p\u003e\n\u003cp\u003e2.2025 Foshan Science and Technology Innovation Project [grant numbers 2520001002838].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and analyzed in the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study protocol was reviewed and approved by the Medical Ethics Committee of Youjiang Medical university for nationalities. (Ethics Review No. 2022010401) .The trial was registered on November 04, 2025 at http://www.chictr.org.cn(Clinical trial number：ChiCTR2500111707), adhered to the CONSORT statement, and was conducted in accordance with the principles of the Declaration of Helsinki. Informed consent was obtained from all participants, who were informed of their rights, including the option to withdraw from the study at any stage.\u0026nbsp;\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 interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZHOU Zhili,LIN Xuezheng,CHEN Jian et al. Effect of dexmedetomidine epidural self-controlled analgesia on prolactin secretion and stress-inflammatory response after cesarean section in expectant mothers[J]. Guangdong Medicine,2021,42(05):594-597.\u003c/li\u003e\n\u003cli\u003eZeng J, Sun X, Luo M, Rao Y, Gong G. Butorphanol Tartrate Nasal Spray for Post-Cesarean Analgesia and Prolactin Secretion. Med Sci Monit. 2025 Jan 21;31:e945224.\u003c/li\u003e\n\u003cli\u003eNairi Gizi G\u0026uuml;laiti, Xu Guiping. Effect of multimodal analgesia on maternal lactogen after cesarean section[J]. China Maternal and Child Health Care,2018,33(03):499-501.\u003c/li\u003e\n\u003cli\u003eLU Yonghong CHEN, Ruihong CHEN Xiaoli et al. Relationship between changes in serum Hcy, prolactin and progesterone and postpartum depression[J]. Experimental and Laboratory Medicine,2019,37(06):1138-1139+1142.\u003c/li\u003e\n\u003cli\u003eBauchat Jeanette Ｒ，Weiniger Carolyn F，Pervez S，et al． Society for obstetric anesthesia and perinatology consensus statement: monitoring recommendations for prevention and detection of respiratory depression associated with administration of neuraxial morphine for cesarean delivery analgesia． Anesth Analg，2019， 129( 2) : 458-474．\u003c/li\u003e\n\u003cli\u003eZheng K, Chen B, Sun J. Nalbuphine May Be Superior to Sufentanil in Relieving Postcesarean Uterine Contraction Pain in Multiparas: A Retrospective Cohort Study. Drug Des Devel Ther. 2023 May 8;17:1405-1415.\u003c/li\u003e\n\u003cli\u003eWang L, Wang Y, Ma Y, Mu X, Zhang Z, Wang H, Zheng Z, Nie H. Sufentanil Combined with Nalbuphine via Patient-Controlled Intravenous Analgesia After Cesarean Section: A Retrospective Evaluation. Drug Des Devel Ther. 2022 Oct 21;16:3711-3721.\u003c/li\u003e\n\u003cli\u003eSchoppmann S, Spiess D, M\u0026uuml;ller D, Burch A, Zimmermann R, Sim\u0026otilde;es-W\u0026uuml;st AP. Nalbuphine: a candidate for treatment of women overwhelmed with sudden, intense labor pain? J Matern Fetal Neonatal Med. 2022 Dec;35(25):6112-6114.\u003c/li\u003e\n\u003cli\u003ePRICE D D,MCGRATH P A,RAFII A,et al. The validation of visual analogue scales as ratio scale measures for chronic and experimental pain[J]. Pain, 1983, 17(1):45-56.\u003c/li\u003e\n\u003cli\u003eRAMSAY M A,SAVEGE T M,SIMPSON B R,et al. Controlled sedation with alphaxalone-alphadolone[J]. British Medical Journal, 1974,2(5920):656-659.\u003c/li\u003e\n\u003cli\u003eSultan P, Sultan E, Carvalho B. Regional anaesthesia for labour, operative vaginal delivery and caesarean delivery: a narrative review. Anaesthesia. 2021 Jan;76 Suppl 1:136-147.\u003c/li\u003e\n\u003cli\u003eJunge J, Inchiosa MA, Xu JL. Exploring the transversus abdominis plane block in cesarean sections and the subsequent toxicity risk to neonates via breast milk. J Anaesthesiol Clin Pharmacol. 2019 Apr-Jun;35(2):153-156.\u003c/li\u003e\n\u003cli\u003eElshazly M, El-Halafawy YM, Mohamed DZ, Wahab KAE, Mohamed TMK. The Feasibility and Efficacy of erector spinae plane block versus Transversus Abdominis Plane Block In Laparoscopic Bariatric Surgery : A Randomized Comparative Trial. Korean J Anesthesiol. 2022 May 18.\u003c/li\u003e\n\u003cli\u003eRyu C, Choi GJ, Jung YH, Baek CW, Cho CK, Kang H. Postoperative Analgesic Effectiveness of Peripheral Nerve Blocks in Cesarean Delivery: A Systematic Review and Network Meta-Analysis. J Pers Med. 2022 Apr 14;12(4):634. \u003c/li\u003e\n\u003cli\u003eGuinn NR, Schwartz J, Arora RC, Morton-Bailey V, Aronson S, Brudney CS, Bennett-Guerrero E; Perioperative Quality Initiative (POQI-8) and the Enhanced Recovery After Surgery-Cardiac Society (ERAS-C) Investigators. Perioperative Quality Initiative and Enhanced Recovery After Surgery-Cardiac Society Consensus Statement on the Management of Preoperative Anemia and Iron Deficiency in Adult Cardiac Surgery Patients. Anesth Analg. 2022 Sep 1;135(3):532-544.\u003c/li\u003e\n\u003cli\u003eHuang JY, Wang LZ, Chang XY, Xia F. Impact of Transversus Abdominis Plane Block With Bupivacaine or Ropivacaine Versus Intrathecal Morphine on Opioid-related Side Effects After Cesarean Delivery: A Meta-analysis of Randomized Controlled Trials. Clin J Pain. 2021 Dec 17;38(3):231-239. \u003c/li\u003e\n\u003cli\u003eSilverman M, Zwolinski N, Wang E, Lockwood N, Ancuta M, Jin E, Li J. Regional Analgesia for Cesarean Delivery: A Narrative Review Toward Enhancing Outcomes in Parturients. J Pain Res. 2023 Nov 10;16:3807-3835.\u003c/li\u003e\n\u003cli\u003eHuang CY, Li SX, Yang MJ, Xu LL, Chen XZ. A comparative study of three concentrations of intravenous nalbuphine combined with hydromorphone for post-cesarean delivery analgesia. Chin Med J (Engl). 2020 Mar 5;133(5):523-529.\u003c/li\u003e\n\u003cli\u003eGoletiani NV, Mendelson JH, Sholar MB, Siegel AJ, Skupny A, Mello NK. Effects of nalbuphine on anterior pituitary and adrenal hormones and subjective responses in male cocaine abusers. Pharmacol Biochem Behav. 2007 Apr;86(4):667-77.\u003c/li\u003e\n\u003cli\u003eREN Yingying,LIU Dingguo. Comparison of the effects of nalbuphine combined with ropivacaine and alone in intrathecal labor analgesia[J]. Heilongjiang Medicine,2023,47(02):150-153.\u003c/li\u003e\n\u003cli\u003eIbrahim AS, Aly MG, Thabet ME, Abdelaziz MR. Effect of adding nalbuphine to intrathecal bupivacaine with morphine on postoperative nausea and vomiting and pruritus after elective cesarean delivery: a randomized double blinded study. Minerva Anestesiol. 2019 Mar;85(3):255-262.\u003c/li\u003e\n\u003cli\u003eZeng Z, Lu J, Shu C, Chen Y, Guo T, Wu QP, Yao SL, Yin P. A comparision of nalbuphine with morphine for analgesic effects and safety : meta-analysis of randomized controlled trials. Sci Rep. 2015 Jun 3;5:10927. \u003c/li\u003e\n\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":"Nabuphine, transverse abdominis plane block, cesarean section, prolactin, nerve block","lastPublishedDoi":"10.21203/rs.3.rs-8466755/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8466755/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective.\u003c/strong\u003e To investigate the impact in women of nalbuphine and ropivacaine transverse abdominis plane block (TAPB) on pain relief and prolactin levels after cesarean section.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods.\u003c/strong\u003e Sixty pregnant women who underwent cesarean section and joint spinal-epidural anesthesia were categorized into two groups: Group A received 20ml of 0.5% ropivacaine and 10ml of normal saline injected into each side; Group B received 20ml of 0.5% ropivacaine, 1ml of nalbuphine, and 9ml of normal saline injected into each side. Serum prolactin (PRL) and cortisol levels were recorded before the operation (T0), and 2 (T1) and 24 (T4) hours after anesthesia. The time when colostrum was expressed was also recorded. The visual analogue scale (VAS) and Ramsay sedation scores were recorded at 2 (T1), 6 (T2), 12 (T3), and 24 hours (T4) after surgery. The incidence of postoperative nausea, vomiting, respiratory depression, itching, bradycardia, colostrum, and analgesic pump use were recorded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults.\u003c/strong\u003e Relative to group B, the prolactin levels pre-surgery (T0) showed no notable variance (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05), although the prolactin levels at 2 (T1) and 24 hours (T4) post-surgery were considerably greater in group B than in group A (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). Colostrum production occurred sooner in group B than in group A (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). Prior to surgery (T0), the cortisol levels in group A and group B showed no notable variance (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05); however, the cortisol concentrations in group A at 2 (T1) and 24 hours (T4) post-surgery were considerably greater than those in group B (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). Differences were found in the frequency of negative reactions between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05). In group B, the VAS pain levels were significantly lower than those in group A at T1–T4 (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05). No notable variance was observed in the Ramsay sedation scores between the two groups at T1-T4 (\u003cem\u003eP\u003c/em\u003e\u0026gt; 0.05). Moreover, group B used an analgesic pump less frequently than group A (\u003cem\u003eP\u003c/em\u003e\u0026lt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion.\u003c/strong\u003e Nalbuphine combined with ropivacaine in transversus abdominis plane block may enhance maternal serum prolactin secretion, facilitating early lactation; It may also reduce serum cortisol levels, alleviating postoperative stress responses in cesarean section patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTrial registration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe trial was registered on November 04, 2025 at http://www.chictr.org.cn.(Clinical trial number：ChiCTR2500111707). Retrospectively registered.\u003c/p\u003e","manuscriptTitle":"Effect of Nalbuphine Combined with Ropivacaine on Analgesia and Prolactin after Cesarean Section","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-02 19:30:43","doi":"10.21203/rs.3.rs-8466755/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":"5b8c6029-ce98-4a58-a0c5-fef2f024c728","owner":[],"postedDate":"February 2nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-24T06:42:10+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-02 19:30:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8466755","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8466755","identity":"rs-8466755","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}