Postoperative nausea and vomiting (PONV) is a common adverse effect of anesthesia. Identifying risk factors for PONV is crucial because it is associated with a longer stay in the post-anesthesia care unit, readmissions, and perioperative costs. This retrospective study used artificial intelligence to analyze data of 37,548 adult patients (aged ≥20 years) who underwent surgery under general anesthesia at Tohoku University Hospital from January 1, 2010 to December 31, 2019. To evaluate PONV, patients who experienced nausea and/or vomiting or used antiemetics within 24 hours after surgery were extracted from postoperative medical and nursing records. We create a model that predicts probability of PONV using the gradient tree boosting model, which is a widely used machine learning algorithm in many applications due to its efficiency and accuracy. The model implementation used the LightGBM framework. Data were available for 33,676 patients. Total blood loss was identified as the strongest contributor to PONV, followed by sex, total infusion volume, and patient\'s age. Other identified risk factors were duration of surgery (60-400 min), no blood transfusion, use of desflurane for maintenance of anesthesia, laparoscopic surgery, lateral positioning during surgery, propofol not used for maintenance of anesthesia, and epidural anesthesia at the lumbar level. The duration of anesthesia and the use of either sevoflurane or fentanyl were not identified as risk factors for PONV. We used artificial intelligence to evaluate the extent to which risk factors for PONV contribute to the development of PONV. Intraoperative total blood loss was identified as the potential risk factor most strongly associated with PONV, although it may correlate with duration of surgery, and insufficient circulating blood volume. The use of sevoflurane and fentanyl and the anesthesia time were not identified as risk factors for PONV in this study.

BACKGROUND: This is an updated and expanded version of the original Cochrane review, first published in 2014. Postoperative oral intake is traditionally withheld after major abdominal gynaecologic surgery until the return of bowel function. The concern is that early oral intake will result in vomiting and severe paralytic ileus, with subsequent aspiration pneumonia, wound dehiscence, and anastomotic leakage. However, clinical studies suggest that there may be benefits from early postoperative oral intake. Currently, gynaecologic surgery can be performed through various routes: open abdominal, vaginal, laparoscopic, robotic, or a combination. In this version, we included women undergoing major gynaecologic surgery through all of these routes, either alone or in combination.
OBJECTIVE: To assess the effects of early versus delayed (traditional) initiation of oral intake of food and fluids after major gynaecologic surgery.
METHODS: On 13 June 2023, we searched the Cochrane Gynaecology and Fertility Group\'s Specialised Register, CENTRAL, MEDLINE, Embase, the citation lists of relevant publications, and two trial registries. We also contacted experts in the field for any additional studies.
METHODS: We included randomised controlled trials (RCTs) that compared the effect of early versus delayed initiation of oral intake of food and fluids after major gynaecologic surgery, performed by abdominal, vaginal, laparoscopic, and robotic approaches. Early feeding was defined as oral intake of fluids or food within 24 hours post-surgery, regardless of the return of bowel function. Delayed feeding was defined as oral intake after 24 hours post-surgery, and only after signs of postoperative ileus resolution. Primary outcomes were: postoperative ileus, nausea, vomiting, cramping, abdominal pain, bloating, abdominal distension, need for postoperative nasogastric tube, time to the presence of bowel sounds, time to the first passage of flatus, time to the first passage of stool, time to the start of a regular diet, and length of postoperative hospital stay. Secondary outcomes were: infectious complications, wound complications, deep venous thrombosis, urinary tract infection, pneumonia, satisfaction, and quality of life.
METHODS: Two review authors independently selected studies, assessed the risk of bias, and extracted the data. We calculated the risk ratio (RR) with a 95% confidence interval (CI) for dichotomous data. We examined continuous data using the mean difference (MD) and a 95% CI. We tested for heterogeneity between the results of different studies using a forest plot of the meta-analysis, the statistical tests of homogeneity of 2 x 2 tables, and the I² value. We assessed the certainty of the evidence using GRADE methods.
RESULTS: We included seven randomised controlled trials (RCTs), randomising 902 women. We are uncertain whether early feeding compared to delayed feeding has an effect on postoperative ileus (RR 0.49, 95% CI 0.21 to 1.16; I² = 0%; 4 studies, 418 women; low-certainty evidence). We are uncertain whether early feeding affects nausea or vomiting, or both (RR 0.94, 95% CI 0.66 to 1.33; I² = 67%; random-effects model; 6 studies, 742 women; very low-certainty evidence); nausea (RR 1.24, 95% CI 0.51 to 3.03; I² = 74%; 3 studies, 453 women; low-certainty evidence); vomiting (RR 0.83, 95% CI 0.52 to 1.32; I² = 0%; 4 studies, 559 women; low-certainty evidence), abdominal distension (RR 0.99, 95% CI 0.75 to 1.31; I² = 0%; 4 studies, 559 women; low-certainty evidence); need for postoperative nasogastric tube placement (RR 0.46, 95% CI 0.14 to 1.55; 3 studies, 453 women; low-certainty evidence); or time to the presence of bowel sounds (MD -0.20 days, 95% CI -0.46 to 0.06; I² = 71%; random-effects model; 3 studies, 477 women; low-certainty evidence). There is probably no difference between the two feeding protocols for the onset of flatus (MD -0.11 days, 95% CI -0.23 to 0.02; I² = 9%; 5 studies, 702 women; moderate-certainty evidence). Early feeding probably results in a slight reduction in the time to the first passage of stool (MD -0.18 days, 95% CI -0.33 to -0.04; I² = 0%; 4 studies, 507 women; moderate-certainty evidence), and may lead to a slightly sooner resumption of a solid diet (MD -1.10 days, 95% CI -1.79 to -0.41; I² = 97%; random-effects model; 3 studies, 420 women; low-certainty evidence). Hospital stay may be slightly shorter in the early feeding group (MD -0.66 days, 95% CI -1.17 to -0.15; I² = 77%; random-effects model; 5 studies, 603 women; low-certainty evidence). The effect of the two feeding protocols on febrile morbidity is uncertain (RR 0.96, 95% CI 0.75 to 1.22; I² = 47%; 3 studies, 453 women; low-certainty evidence). However, infectious complications are probably less common in women with early feeding (RR 0.20, 95% CI 0.05 to 0.73; I² = 0%; 2 studies, 183 women; moderate-certainty evidence). There may be no difference between the two feeding protocols for wound complications (RR 0.82, 95% CI 0.50 to 1.35; I² = 0%; 4 studies, 474 women; low-certainty evidence), or pneumonia (RR 0.35, 95% CI 0.07 to 1.73; I² = 0%; 3 studies, 434 women; low-certainty evidence). Two studies measured participant satisfaction and quality of life. One study found satisfaction was probably higher in the early feeding group, while the other study found no difference. Neither study found a significant difference between the groups for quality of life (P > 0.05).
CONCLUSIONS: Despite some uncertainty, there is no evidence to indicate harmful effects of early feeding following major gynaecologic surgery, measured as postoperative ileus, nausea, vomiting, or abdominal distension. The potential benefits of early feeding include a slightly faster initiation of bowel movements, a slightly sooner resumption of a solid diet, a slightly shorter hospital stay, a lower rate of infectious complications, and a higher level of satisfaction.

BACKGROUND: OFA (Opioid-free anesthesia) has the potential to reduce the occurrence of opioid-related adverse events and enhance postoperative recovery. Our research aimed to investigate whether OFA, combining esketamine and dexmedetomidine, could serve as an alternative protocol to traditional OBA (opioid-based anesthesia) in shoulder arthroscopy, particularly in terms of reducing PONV (postoperative nausea and vomiting).
METHODS: A total of 60 patients treated with shoulder arthroscopy from September 2021 to September 2022 were recruited. Patients were randomly assigned to the OBA group (n = 30) and OFA group (n = 30), receiving propofol-remifentanil TIVA (total intravenous anesthesia) and esketamine-dexmedetomidine intravenous anesthesia, respectively. Both groups received ultrasound-guided ISBPB(interscalene brachial plexus block)for postoperative analgesia.
RESULTS: The incidence of PONV on the first postoperative day in the ward (13.3% vs. 40%, P < 0.05) was significantly lower in the OFA group than in the OBA group. Moreover, the severity of PONV was less severe in the OFA group than in the OBA group in PACU (post-anesthesia care unit) (0 [0, 0] vs. 0 [0, 3], P<0.05 ) and in the ward 24 h postoperatively ( 0 [0, 0] vs. 0 [0, 2.25], P<0.05). Additionally, the OFA group experienced a significantly shorter length of stay in the PACU compared to the OBA group (39.4 ± 6.76 min vs. 48.7 ± 7.90 min, P < 0.001).
CONCLUSIONS: Compared to the OBA with propofol-remifentanil, the OFA with esketamine- dexmedetomidine proved to be feasible for shoulder arthroscopy, resulting in a reduced incidence of PONV and a shorter duration of stay in the PACU.
BACKGROUND: The Chinese Clinical Trial Registry (No: ChiCTR2100047355), 12/06/2021.

BACKGROUND: Post-operative nausea and vomiting remain an unresolved concern in Türkiye and some parts of the world, impacting the quality of the patient\'s recovery process and diminishing overall satisfaction.
OBJECTIVE: This study was conducted as a descriptive investigation to compare the incidence of nausea and vomiting following breast cancer surgery with the nausea and vomiting risk scores proposed by Apfel and Koivuranta.
METHODS: This study was conducted with 100 patients admitted to the General Surgery service of a university hospital between 31 August 2019 and 31 May 2021 for breast cancer surgery. The patient information form developed by the researchers, Apfel Nausea and Vomiting Risk Score, and Koivuranta Nausea and Vomiting Risk Score were used as data collection tools.
RESULTS: It was identified that 61% of the patients experienced nausea and vomiting within the initial 24 h following surgery. A significant correlation was found between age, post-operative opioid use, motion sickness or history of PONV, and nausea and vomiting (p < 0,05). The sensitivity of the Apfel score obtained was 80%, the specificity was 46%, and the AUC value was 0.686. The sensitivity of the Koivuranta score was 80%, the specificity was 35%, and the AUC value was 0.675 (p < 0.05).
CONCLUSIONS: It has been observed that patients experience high rates of nausea and vomiting after breast cancer surgery and that the Apfel and Koivuranta Risk Scores are equally applicable in predicting post-operative nausea and vomiting.

UNASSIGNED: Pre-operative prediction of postoperative nausea and vomiting (PONV) is primarily based on the patient\'s medical history. The predictive value of gastric morphological parameters observed on ultrasonography has not been comprehensively assessed.
UNASSIGNED: A prospective observational study was conducted to evaluate the pre-operative ultrasonographic measurement of gastric morphology for predicting PONV. The gastric antrum of the participants was assessed using ultrasound before anesthesia, and the occurrence of PONV in the first 6 hours and during the 6-24 hours after surgery was reported. The main indicators included the thickness of the muscularis propria (TMP) and the cross-sectional area of the inner side of the muscularis propria (CSA-ISMP). These were recorded and analyzed. Logistic regression analysis was applied to identify factors for PONV.
UNASSIGNED: A total of 72 patients scheduled for elective gynecological laparoscopic surgery were investigated in the study. The pre-operative CSA-ISMP of patients with PONV in the first 6 hours was significantly greater than that of those without PONV (2.765 ± 0.865 cm² vs 2.349 ± 0.881 cm², P=0.0308), with an area under the curve of 0.648 (95% CI, 0.518 to 0.778, P=0.031). Conversely, the pre-operative TMP of patients with PONV during the 6-24 hours was significantly smaller than that of those without PONV (1.530 ± 0.473 mm vs 2.038 ± 0.707 mm, P=0.0021), with an area under the curve of 0.722 (95% CI, 0.602 to 0.842, P=0.003). Logistic regression analysis confirmed that CSA-ISMP was an independent risk factor for PONV in the first 6 hours (OR=2.986, P=0.038), and TMP was an independent protective factor for PONV during the 6-24 hours after surgery (OR=0.115, P=0.006).
UNASSIGNED: Patients with a larger pre-operative CSA-ISMP or a thinner TMP are prone to develop PONV in the first 6 hours or during the 6-24 hours after surgery, respectively.
UNASSIGNED: http://www.chictr.org.cn (ChiCTR2100055068).

BACKGROUND: Intrathecal morphine provides effective analgesia for a range of operations. However, widespread implementation into clinical practice is hampered by concerns for potential side-effects. We undertook a systematic review, meta-analysis, and meta-regression with the primary objective of determining whether a threshold dose for non-pulmonary complications could be defined and whether an association could be established between dose and complication rates when intrathecal morphine is administered for perioperative or obstetric analgesia.
METHODS: We systematically searched the literature for randomised controlled trials comparing intrathecal morphine vs control in patients undergoing any type of surgery under general or spinal anaesthesia, or women in labour. Primary outcomes were rates of postoperative nausea and vomiting, pruritus, and urinary retention within the first 24 postoperative hours, analysed according to doses (1-100 μg; 101-200 μg; 201-500 μg; >500 μg), type of surgery, and anaesthetic strategy. Trials were excluded if doses were not specified.
RESULTS: Our analysis included 168 trials with 9917 patients. The rates of postoperative nausea and vomiting, pruritus, and urinary retention were significantly increased in the intrathecal morphine group, with an odds ratio (95% confidence interval) of 1.52 (1.29-1.79), P<0.0001; 6.11 (5.25-7.10), P<0.0001; and 1.73 (1.17-2.56), P=0.005, respectively. Meta-regression could not establish an association between dose and rates of non-pulmonary complications. There was no subgroup difference according to surgery for any outcome. The quality of evidence was low (Grading of Recommendations Assessment, Development, and Evaluation [GRADE] system).
CONCLUSIONS: Intrathecal morphine significantly increased postoperative nausea and vomiting, pruritus, and urinary retention after surgery or labour in a dose-independent manner.
UNASSIGNED: PROSPERO (CRD42023387838).

BACKGROUND: Currently, the prevalence of obesity is on the rise annually. Bariatric surgery stands out as the most efficacious approach for addressing obesity. Obese patients are more prone to experience moderate to severe pain after surgery due to lower pain thresholds. Regional block, as an important component of multimodal analgesia in bariatric surgery, is crucial in reducing opioid consumption and alleviating postoperative pain in patients undergoing bariatric surgery. Transversus abdominis plane block (TAPB) has gained widespread utilization in bariatric surgery; however, its limitation of inadequate reduction of visceral pain in obese patients remains a significant concern. Therefore, it is imperative to explore new and more efficient strategies for analgesia. Quadratus lumborum block (QLB) has emerged as a popular nerve block in recent years, frequently utilized in conjunction with general anesthesia for abdominal surgery. In the cadaver study of QLB, it was confirmed that the dye level could reach up to T6 when using the subcostal anterior quadratus lumborum muscle approach, which could effectively reduce the incision pain and visceral pain of bariatric surgery patients during the perioperative period. However, there is currently a lack of research on the use of subcostal anterior QLB in patients undergoing bariatric surgery. Our study aims to investigate whether subcostal anterior QLB can provide superior perioperative analgesic efficacy for bariatric surgery under general anesthesia compared to TAPB, leading to reduced postoperative opioid consumption and a lower incidence of postoperative nausea and vomiting (PONV).
METHODS: This study is a prospective, randomized controlled trial aiming to recruit 66 patients undergoing bariatric surgery. The participants will be randomly allocated into two groups in a 1:1 ratio: subcostal anterior QLB group (n = 33) and TAPB group (n = 33). The study aims to investigate the efficacy of subcostal anterior QLB and TAPB in obese patients who are scheduled to undergo bariatric surgery. Our primary outcome is to observe the amount of opioids used in the two groups 24 h after operation. The secondary outcomes included VAS of pain during rest/activity after operation, the type and dose of additional analgesics, the occurrence and severity of PONV, the type and dose of additional antiemetic drugs, postoperative anesthesia care unit (PACU) time, time of first postoperative exhaust, time to first out of bed activity, time to first liquid diet and postoperative admission days.
CONCLUSIONS: Opioid analgesics are prone to causing adverse reactions such as nausea, vomiting, and respiratory depression, especially in obese patients. Multimodal analgesia, including nerve block, can effectively reduce the dose of opioids and alleviate their adverse effects. Currently, TAPB is the most prevalent nerve block analgesia method for abdominal surgery. Recent studies have indicated that subcostal anterior QLB offers advantages over TAPB, including a wider block plane, faster onset, and longer maintenance time. It is not clear which of the two nerve block analgesia techniques is better for postoperative analgesia in patients undergoing bariatric surgery. Our objective in this investigation is to elucidate the superior method between TAPB and subcostal anterior QLB for postoperative pain management in bariatric surgery.
BACKGROUND: ChiCTR ChiCTR2300070556. Registered on 17 April 2023.

BACKGROUND: Bariatric surgery is one of the most effective ways to treat morbid obesity, and postoperative nausea and vomiting (PONV) is one of the common complications after bariatric surgery. At present, the mechanism of the high incidence of PONV after weight-loss surgery has not been clearly explained, and this study aims to investigate the effect of surgical position on PONV in patients undergoing bariatric surgery.
OBJECTIVE: To explore the effect of the operative position during bariatric surgery on PONV.
METHODS: Data from obese patients, who underwent laparoscopic sleeve gastrectomy (LSG) in the authors\' hospital between June 2020 and February 2022 were divided into 2 groups and retrospectively analyzed. Multivariable logistic regression analysis and the t-test were used to study the influence of operative position on PONV.
RESULTS: There were 15 cases of PONV in the supine split-leg group (incidence rate, 50%) and 11 in the supine group (incidence rate, 36.7%) (P = 0.297). The mean operative duration in the supine split-leg group was 168.23 ± 46.24 minutes and 140.60 ± 32.256 minutes in the supine group (P < 0.05). Multivariate analysis revealed that operative position was not an independent risk factor for PONV (odds ratio = 1.192, 95% confidence interval: 0.376-3.778, P = 0.766).
CONCLUSIONS: Operative position during LSG may affect PONV; however, the difference in the incidence of PONV was not statistically significant. Operative position should be carefully considered for obese patients before surgery.

UNASSIGNED: Previously, we reported that antiemetics (droperidol and/or dexamethasone) could significantly reduce the incidence of postoperative nausea and vomiting (PONV) after laparoscopic gynecological surgery (LGS). We retrospectively investigated anesthesia practice during the era earlier than the above-mentioned report to identify factors affecting PONV.
UNASSIGNED: We investigated 1,221 patients who underwent LGS at Juntendo University Hospital between 2007 and 2009. Effects of nine covariates likely to affect PONV on the actual incidence of PONV were examined with the multivariate logistic regression analysis.
UNASSIGNED: The actual incidence of PONV developing until nine hours after the transfer to the ward was 47.3% (577/1,221) in the total cohort. The multivariate logistic regression analysis revealed that longer duration of anesthesia (in hours) was associated with the increased incidence of PONV (odds ratio [OR], 1.170; 95% confidence interval [CI], 1.000-1.360; p = 0.0467), the use of the reversal agent neostigmine co-administrated with atropine was associated with the lower incidence of PONV (OR, 0.746; 95% CI, 0.585-0.950; p = 0.0177), and no use of PCA and the use of fentanyl PCA without droperidol were associated with the higher incidence of PONV, compared with the use of fentanyl PCA with droperidol (OR, 1.810; 95% CI, 1.250-2.640; p = 0.0019; and OR, 2.500; 95% CI, 1.880-3.310; p < 0.0001; respectively).
UNASSIGNED: Longer duration of anesthesia was associated with the increased incidence of PONV. Addition of droperidol to the PCA infusate and the use of reversal agent neostigmine co-administrated with atropine were associated with the reduced incidence of PONV.

This meta-analysis investigated the effects of intravenous magnesium sulfate on the postoperative recovery quality, as assessed using the Quality of Recovery (QoR) questionnaire, in adult surgical patients. Seven randomized controlled trials involving 622 patients were included. Compared with the placebo, magnesium sulfate significantly improved the global QoR score on postoperative day 1 (standardized mean difference [SMD]: 1.24; 95% confidence interval: 0.70-1.78; p < 0.00001). It also enhanced specific QoR dimensions, with substantial effects on pain (SMD: 1, p < 0.00001) and physical comfort (SMD: 0.85, p < 0.0001), a moderate effect on emotional state (SMD: 0.65, p = 0.002), and small improvements in physical independence (SMD: 0.43, p < 0.00001) and psychological support (SMD: 0.37, p < 0.0001). In addition, magnesium sulfate reduced the intraoperative opioid consumption (SMD: -0.66, p < 0.0001), postoperative pain severity, and the incidence of postoperative nausea and vomiting (risk ratio: 0.48, p = 0.008). The extubation times were unaffected, whereas the post-anesthesia care unit stay was slightly prolonged. These findings highlight the potential of magnesium sulfate as a valuable adjunct for multimodal analgesia and enhanced recovery. Future studies should aim to elucidate the optimal dosing strategies, timing of administration, and specific surgical populations that may derive maximum benefits.