Postoperative nausea and vomiting (PONV) after orthognathic surgery: a retrospective study and literature review

Do Regional Nerve Blocks During Bimaxillary Surgery Decrease Postoperative Pain and Vomiting Compared With Patient-Controlled Analgesia?

BACKGROUND

Postoperative pain after orthognathic surgery is commonly managed with opioids, which can cause nausea and vomiting.

PURPOSE

The purpose of this study was to determine whether regional nerve blocks during bimaxillary surgery reduced postoperative pain and vomiting compared with patient-controlled analgesia (PCA).

STUDY DESIGN, SETTING, AND SAMPLE

This retrospective cohort study recruited patients who underwent bimaxillary surgery between August 2018 and September 2020 at the Fourth Military Medical University Hospital. Participants whose procedures involved the cheekbone, temporomandibular joint, mandibular angle, or an autogenous iliac bone graft and those who were admitted to the intensive care unit after surgery were excluded.

PREDICTOR VARIABLES

The primary predictor variables were postoperative analgesia management, regional maxillary and inferior alveolar nerve blocks, and PCA.

OUTCOME VARIABLES

The primary outcome variables were moderate-to-severe postoperative pain and postoperative vomiting (POV) during the first 24 hours. Moderate-to-severe pain was defined as pain numerical rating scale ≥4, POV was defined as vomiting of gastrointestinal contents.

COVARIATES

The study covariates included demographic, surgical, and anesthesia characteristics.

ANALYSES

Statistical analyses were conducted using an unpaired t-test, χ2 test, or Fisher's exact test for the bivariate analysis. A multivariate logistic regression analysis was performed to assess the associations between the primary predictor variables and outcomes. Statistical significance was set at P < .05.

RESULTS

354 participants were included in the study (262 in the nerve block group, mean age 22.5 ± 4.0 years; 92 in the PCA group, mean age 22.6 ± 4.4 years; P = .81). There was no significant difference in sex between the groups (63.4 and 55.4% females in nerve block and PCA groups, respectively, P = .18). The multivariate regression analyses demonstrated that nerve blocks did not decrease moderate-to-severe postoperative pain (7.6 vs 10.9%, adjusted odds ratio = 0.67, 95% confidence interval: 0.22-2.01, P = .48), although they were associated with decreased POV (38.5 vs 65.2%, adjusted odds ratio = 0.34, 95% confidence interval: 0.18-0.65, P = .001).

CONCLUSION AND RELEVANCE

For bimaxillary surgery, regional nerve blocks as opioid-free postoperative analgesia were not significantly associated with decreased postoperative pain but were associated with a lower POV risk.

Postoperative nausea and vomiting in orthognathic surgery: systematic review and meta-analysis

PURPOSE

Postoperative nausea and vomiting (PONV) is a frequently reported adverse event following orthognathic surgery. The aim of this work is to conduct a systematic review of the literature on the subject, and to discuss the role of maxillofacial surgeons and the steps that can be taken to prevent or control PONV in orthognathic surgery.

METHODS

A systematic review was conducted according to the PRISMA guidelines, using the search strategy: (orthognathic AND (nausea OR vomiting)). The authors searched PubMed, Embase, Dimensions, Web of Science and Google Scholar databases, without any language restrictions. RevMan 5.4 was used to create a risk of bias graph and a forest plot.

RESULTS

The included articles were classified as having a low risk of bias, despite the limited literature on the subject. Various measures have been reported to be beneficial in preventing or managing PONV, such as the use of dexamethasone, antiemetic drugs, gastric aspiration, and anesthetic blocks. Effective bleeding control and faster surgeries can also be helpful.

CONCLUSIONS

Throat packs have not been found to be effective in preventing PONV. Although no definitive protocol has been established in the literature, the Enhanced Recovery After Surgery (ERAS) protocol could be a useful approach. Overall, a multimodal approach may be taken to prevent PONV, and further research is needed to establish definitive protocols.

Impact of general anesthesia on postoperative complications in orthognathic surgery: a retrospective comparison of total intravenous anesthesia versus volatile anesthesia

Orthognathic surgery has a high incidence of postoperative nausea (PON) and vomiting (POV), delaying mobility initiation and postoperative recovery. Bleeding is another risk associated with this surgical procedure. We aimed to compare total intravenous anesthesia (TIVA) and volatile anesthesia in patients undergoing orthognathic surgery in terms of postoperative nausea and vomiting (PONV) incidence and hemodynamic changes. This retrospective study included 82 patients who underwent bilateral sagittal split ramus osteotomies at Saga University Hospital between April 2016 and April 2021. We compared the effects of TIVA and volatile anesthesia on PONV onset after surgery, acute postoperative hemodynamic changes (blood pressure and heart rate), and factors contributing to PONV. PON was significantly lower in the TIVA group than in the volatile anesthesia group. The total dose of fentanyl contributed to the onset of POV, while the onset of PON was associated with low volumes of fluid infusion and urine in the TIVA and volatile anesthesia groups, respectively. Furthermore, post-extubation hemodynamic change was significantly smaller in the TIVA group than in the volatile anesthesia group. Therefore, TIVA could have a reduced risk of PONV and hemodynamic changes in patients undergoing orthognathic surgery. Employing TIVA could mitigate perioperative complications and enhance patient safety.

An Enhanced Recovery After Surgery (ERAS) Protocol for Orthognathic Surgery Reduces Rates of Postoperative Nausea

For many surgical procedures, enhanced recovery after surgery (ERAS) protocols have improved patient outcomes, particularly postoperative nausea and vomiting. The purpose of this study was to evaluate postoperative nausea following orthognathic surgery after the implementation of an ERAS protocol. This retrospective cohort study included patients between 12 and 35 years old who underwent orthognathic surgery at Boston Children's Hospital from April 2018 to December 2022. Patients with syndromes or a hospital stay greater than 48 hours were excluded from the study. The primary predictor was enrollment in our institutional ERAS protocol. The main outcome variable was postoperative nausea. Intraoperative and postoperative covariates were compared between groups using unpaired t tests and chi squared analysis. Univariate and multivariate regression models with 95% confidence intervals were performed to identify predictors for nausea. A P value<0.05 was considered significant. There were 128 patients (68 non-ERAS, 60 ERAS) included in this study (51.6% female, mean age 19.02±3.25 years). The ERAS group received less intraoperative fluid (937.0±462.3 versus 1583.6±847.6 mL, P ≤0.001) and experienced less postoperative nausea (38.3% versus 63.2%, P =0.005). Enhanced recovery after surgery status ( P =0.005) was a predictor for less postoperative nausea, whereas bilateral sagittal split osteotomy ( P =0.045) and length of stay ( P =0.007) were positive predictors for postoperative nausea in multivariate logistic regression analysis. Implementing an ERAS protocol for orthognathic surgery reduces postoperative nausea. Level of Evidence: Level III-therapeutic.

The online attention analysis on orthognathic surgery research

OBJECTIVES

Altmetrics is one of the fields of bibliometrics that seeks to assess the impact and interest of a given subject through Internet users. The aim of this study is to make an altmetric analysis of the orthognathic surgery literature.

METHODS

A literature search was conducted using Dimensions app up to December 2023. A list of the 100 most mentioned articles on the topic was compiled. A Google Trends search was performed with same strategy to visualize important data regarding internet search. Charts and tables were created using Microsoft Excel and VOSviewer software to allow bibliometric visualization.

RESULTS

There was a very poor correlation between the number of mentions and the number of citations (r = 0.0202). Most articles discussed on technical innovations associated to orthognathic surgery, majority related to virtual planning (n = 26). Other topics considered interesting to internet readers were complications (n = 18), surgical technique (n = 14), and psychological aspects/quality of life (n = 13).

CONCLUSION

Online interest in orthognathic surgery closely aligns with the level of academic interest but is also influenced by factors such as location and economic status. The internet is a powerful tool for disseminating scientific research to a broad audience, making it more accessible and engaging than traditional academic channels.

Effects of intra-operative magnesium sulfate infusion on orthognathic surgery: A prospective and randomized controlled trial

Purpose

To comprehensively understand the effects of intra-operative infusion of magnesium sulfate on patients who underwent orthognathic surgery, including remifentanil consumption, postoperative pain, postoperative nausea and vomiting (PONV), inflammatory response, and serum magnesium levels.

Methods

Seventy-five adult patients undergoing orthognathic surgery under general balanced anesthesia were randomly divided into two groups. One group (Group M) received 50 mg/kg of magnesium sulfate in 20 mL 0.9 % saline after intubation, followed by a continuous infusion at a rate of 15 mg/kg/h until 30 min before the anticipated end of surgery. The other group (Group C) received an equal volume of isotonic saline as a placebo. (Clinical trial registration number: chiCTR2100045981).

Results

The primary outcome was remifentanil consumption. The secondary outcomes included the pain score assessed using the verbal numerical rating scale (VNRS) and PONV assessed using a Likert scale. Remifentanil comsumption in Group M was lower than Group C (mean ± SD: 0.146 ± 0.04 μg/kg/min vs. 0.173 ± 0.04 μg/kg/min, P = 0.003). At 2 h after surgery, patients in Group C suffered more severe PONV than those in Group M (median [interquartile range, IQR]: 1 [3] vs. 1 [0], mean rank: 31.45 vs. 42.71, P = 0.040). At post-anesthesia care unit (PACU), postoperative pain in Group C was severe than Group M (3 [1] vs. 3 [0], mean rank: 31.45 vs. 42.71, P = 0.013). Changes in haemodynamics and surgical field scores did not differ between the groups (all P > 0.05). The levels of cytokines (IL-4, IL-6, IL-8, IL-10, TNF-a, and MIP-1β) were not significantly different between the groups after surgery (all P > 0.05). Postoperative serum magnesium levels in Group C were lower than those in Group M (0.74 ± 0.07 mmol/L vs. 0.91 ± 0.08 mmol/L, P = 0.000) and the preoperative level (0.74 ± 0.07 mmol/L vs. 0.83 ± 0.06 mmol/L, P = 0.219).

Conclusions

In orthognathic surgery, magnesium sulfate administration can reduce remifentanil requirement and relieve PONV and postoperative pain in the early postoperative phase.

Prevention of postoperative nausea and vomiting after orthognathic surgery: a scoping review

INTRODUCTION

Postoperative nausea and vomiting (PONV) is one of the most common adverse events following orthognathic surgery. It's a distressing feeling for patients and continues to be the cause of postoperative complications such as bleeding, delayed healing, and wound infection. This scoping review aims to identify effective PONV prophylaxis strategies during orthognathic surgery that have emerged in the past 15 years.

METHODS

We searched Pubmed, Cochrane Controlled Register of Trials, and Embase from 2008 to May 2023. Studies meeting the following criteria were eligible for inclusion: (1) recruited patients undergo any orthognathic surgery; (2) evaluated any pharmacologic or non-pharmacologic method to prevent PONV. Studies meeting the following criteria were excluded: (1) case series, review papers, or retrospective studies; (2) did not report our prespecified outcomes.

RESULTS

Twenty-one studies were included in this review. Pharmacological methods for PONV prevention include ondansetron and dexamethasone (3 studies), peripheral nerve block technique (4 studies), dexmedetomidine (1 study), pregabalin (2 studies), nefopam (2 studies), remifentanil (1 study), propofol (2 studies), and penehyclidine (1 study). Non-pharmacologic methods include capsicum plaster (1 study), throat packs (2 studies) and gastric aspiration (2 studies).

CONCLUSIONS

Based on current evidence, we conclude that prophylactic antiemetics like dexamethasone, ondansetron, and penehyclidine are the first defense against PONV. Multimodal analgesia with nerve block techniques and non-opioid analgesics should be considered due to their notable opioid-sparing and PONV preventive effect. For the non-pharmacological methods, throat packs are not recommended for routine use because of their poor effect and serious complications. More prospective RCTs are required to confirm whether gastric aspiration can prevent PONV effectively for patients undergoing orthognathic surgery.

Does Anesthesiologist Experience Influence Early Postoperative Outcomes Following Orthognathic Surgery?

BACKGROUND

Anesthesia provider experience impacts nausea and vomiting in other surgical specialties but its influence within orthognathic surgery remains unclear.

PURPOSE

The study purpose was to evaluate whether anesthesiologist experience with orthognathic surgery impacts postoperative outcomes, including nausea, emesis, narcotic use, and perioperative adverse events, for patients undergoing orthognathic surgery.

STUDY DESIGN, SETTING, SAMPLE

This is a retrospective cohort study of subjects aged 12 to 35 years old who underwent orthognathic surgery, including Le Fort 1 osteotomy ± bilateral sagittal split osteotomy, at Boston Children's Hospital from August 2018 to January 2022. Subjects were excluded if they had incomplete medical records, a syndromic diagnosis, or a hospital stay of greater than 2 days.

PREDICTOR VARIABLE

The predictor variable was attending anesthesia provider experience with orthognathic surgery. Providers were classified as experienced or inexperienced, with experienced providers defined as having anesthetized ≥10 orthognathic operations during the study period.

MAIN OUTCOME VARIABLES

The primary outcome variable was postoperative nausea. Secondary outcome variables were emesis, narcotic use in the hospital, and perioperative adverse events within 30 days of their operation.

COVARIATES

Study covariates included age, sex, race, comorbidities (body mass index, history of psychiatric illness, cleft lip and/or palate, chronic pain, postoperative nausea/vomiting, gastrointestinal conditions), enhanced recovery after surgery protocol enrollment, and intraoperative factors (operation performed, anesthesia/procedure times, estimated blood loss, intravenous fluid and narcotic administration, and anesthesiologist's years in practice).

ANALYSES

χ2 and unpaired t-tests were used to compare primary predictor and covariates against outcome variables. A P-value <.05 was considered significant.

RESULTS

There were 118 subjects included in the study after 4 were excluded (51.7% female, mean age 19.1 ± 3.30 years). There were 71 operations performed by 5 experienced anesthesiologists (mean cases/provider 15.4 ± 5.95) and 47 cases by 22 different inexperienced providers (mean cases/provider 1.91 ± 1.16). The nausea rate was 52.1% for experienced providers and 53.2% for inexperienced providers (P = .909). There were no statistically significant associations between anesthesiologist experience and any outcome variable (P > .341).

CONCLUSIONS AND RELEVANCE

Anesthesia providers' experience with orthognathic surgery did not significantly influence postoperative nausea, emesis, narcotic use, or perioperative adverse events.

Is Postoperative Pain Associated With Nausea and Vomiting Following Orthognathic Surgery?

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse side-effect following orthognathic surgery, with pain potentially contributing as a risk factor.

PURPOSE

The study's purpose was to measure the association between postoperative pain and PONV.

STUDY DESIGN, SETTING, SAMPLE

This prospective cohort study involved patients who underwent bimaxillary surgery at Erciyes University, Oral and Maxillofacial Surgery Hospital. Patients with a history of routine antiemetic use, pregnancy, breastfeeding, morbid obesity, cardiac dysrhythmia, mental retardation, or psychiatric illness were excluded.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

The predictor variable was postoperative pain, which was measured using a 100-mm visual analogue scale (VAS). VAS scores were documented at the 30-minute postoperative mark (referred to as VAS1), and the mean of hourly VAS scores over the initial three postoperative hours (denoted as VAS2).

MAIN OUTCOME VARIABLE(S)

The primary outcome was the occurrence of PONV, defined as active vomiting, retching, or nausea leading to vomiting. The secondary outcome was the timing of PONV, categorized as early (within 6 hours), late (6-24 hours), and delayed (beyond 24 hours postoperatively).

COVARIATES

The study's covariates were age, sex, body mass index, Apfel risk scores, surgery duration, history of PONV or motion sickness, and smoking status.

ANALYSES

Descriptive statistics and χ2 tests were used for data analysis, with statistical significance set at P value < .05.

RESULTS

The sample was composed of 86 subjects with a median age of 20 years (range: 18-30 years), of which 37.2% were male. The frequency of PONV was 50%. Postoperative pain, as measured by VAS scores, was significantly higher in the PONV group compared to the non-PONV group. The median VAS1 score was 60.0 (PONV group, range 40-90) versus 50.0 (non-PONV, range 0-90) (P = .041); for VAS2, it was 60.0 (PONV, range 40-80) compared to 40.0 (non-PONV, range 30-60) (P < .001).

CONCLUSIONS AND RELEVANCE

The frequency of PONV observed in patients undergoing bimaxillary surgery is substantial, necessitating the identification and management of risk factors to enhance perioperative care and patient outcomes. By improving PONV management and addressing postoperative pain, health-care providers can enhance the perioperative experience and patient outcomes in bimaxillary surgery.

The efficacy of gastric aspiration in reducing postoperative vomiting after oral and maxillofacial surgery: A meta-analysis

BACKGROUND

Gastric aspiration is applied in oral and maxillofacial procedures to reduce postoperative vomiting (POV), yet its clinical benefit remains largely uncertain. Our study aimed to determine the role of gastric aspiration in the amelioration of POV by a meta-analysis.

METHODS

With adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, global recognized databases, including PubMed, Embase, and Cochrane Central, were searched to obtain randomized controlled trials (RCTs) investigating the effects of gastric aspiration in oral and maxillofacial surgery. The incidence and the number of episodes of POV and the frequency of rescue antiemetic use were extracted as parametric data for pooled estimation. Funnel plots and Egger's test were utilized to assess bias. The recommendation of evidence was rated by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system.

RESULTS

After detailed evaluation, 5 RCTs containing 274 participants were eventually included. The results of pooled estimation indicated that gastric aspiration could not reduce the incidence of POV (risk ratio [95% CI] = 0.94 [0.73, 1.21], P = .621), the number of episodes of POV (standard mean difference [95% CI] = -0.13 [-0.45, 0.19], P = .431) or the frequency of rescue antiemetic use (RR [95% CI] = 0.86 [0.49, 1.52], P = .609). No publication bias was detected by the funnel plot and Egger test. The overall recommendation of evidence was rated low regarding each outcome.

CONCLUSION

Based on current evidence, gastric aspiration is not recommended for oral and maxillofacial surgery. Meanwhile, more large-scale high-quality RCTs are needed.

Enhanced recovery pathways for head and neck surgery with free tissue transfer reconstruction

The enhanced recovery after surgery (ERAS) pathway is designed to facilitate recovery after surgery by packaging evidence-based protocols specific to each aspect of the perioperative period, including the preoperative, intraoperative, postoperative, and post-discharge periods. The ERAS pathway, which was originally developed for use with colonic resection, is now being expanded to include a variety of surgical procedures, and the ERAS Society has published a consensus review of the ERAS pathway for head and neck surgery with free tissue transfer reconstruction (HNS-FTTR). The ERAS pathway for HNS-FTTR consists of various important protocols, including early postoperative mobilization, early postoperative enteral nutrition, abolition of preoperative fasting, preoperative enteral fluid loading, multimodal pain management, and prevention of postoperative nausea and vomiting. In recent years, meta-analyses investigating the utility of the ERAS pathway in head and neck cancer surgery have also been presented, and all reports showed that the length of the postoperative hospital stay was reduced by the implementation of the ERAS pathway. The ERAS pathway is now gaining traction in the field of head and neck surgery; however, the details of its efficacy remain uncertain. We believe the future direction will require research focused on improving the quality of postoperative patient recovery and patient satisfaction. It will be important to use patient-reported outcomes to determine whether the ERAS pathway is actually beneficial.

The Pharyngeal Packs for Dental and Otolaryngological Surgery: A Meta-Analysis of High-Quality Randomized Controlled Trials

Background: Pharyngeal packs are employed to mitigate postoperative nausea and vomiting (PONV) and have become prevalent in dental and otolaryngological surgeries. However, their clinical efficacy continues to be a topic of debate. The objective of the present study was to conduct a quantitative assessment of the impact of pharyngeal packing in dental and otolaryngological surgeries through meta-analysis. Methods: We identified relevant randomized controlled trials (RCTs) through systematic searches of online databases, including PubMed, Embase, and Cochrane Central. Potential eligible studies were evaluated using the Jadad scoring system (range 0-5 points), with only high-quality RCTs (3 points or more) being included. The incidence of PONV, morbidity, and the level of throat pain were aggregated and estimated. Publication bias was evaluated using funnel plot symmetry and the Egger test. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was utilized to rate the evidence. Results: Ten high-quality RCTs comprising 1026 participants were ultimately included. Subsequent quantitative pooled estimation unveiled that the utilization of pharyngeal packing did not lead to a significant reduction in the incidence of nausea (P = .272), vomiting (P = .775), overall PONV (P = .118), or throat pain (P = .149). By contrast, the application of pharyngeal packs was found to significantly increase the level of throat pain (P = .003). No obvious publication bias was detected, and the majority of evidence was rated high or moderate. Conclusion: Based on the existing evidence, we conclude that pharyngeal packing lacks clinical benefit and is not advised for dental and otolaryngological surgeries.

Assessing the impact of aprepitant and ondansetron on postoperative nausea and vomiting in orthognathic surgeries: a randomized controlled trial

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common side effect associated with general anesthesia. Both ondansetron and aprepitant been effectively used to prevent PONV. However, there is a disagreement of opinions regarding the superiority of these two drugs. This study aims to compare the efficacy of aprepitant with ondansetron in preventing PONV following orthognathic surgeries.

METHODS

In this double-blinded clinical trial, 80 patients scheduled for orthognathic surgery at Imam Hossein Hospital, Tehran, Iran, were randomly assigned to two groups. A standardized anesthesia protocol was used for all patients. The first group received a placebo capsule administered one hour before the surgical procedure along with 4 mg (2 ml) of ondansetron intravenously after anesthesia induction. The second group was given 80 mg aprepitant capsules one hour before the surgery, followed by an injection of 2 ml intravenous distilled water after anesthesia induction. The occurrence and severity of PONV, the amount of rescue medication required, and the complete response of patients assessed within 24 h after the surgery.

RESULTS

There were no significant differences in demographic data between the two groups. Patients in the aprepitant group had a significantly lower incidence and severity of nausea (2.5% versus 27.5%), vomiting (5% versus 25%), and required fewer rescue medications (7.5% versus 62.5%) compared to the ondansetron group. Additionally, the aprepitant group showed a higher complete response rate (90% versus 67.5%) in the 0-2 and 12-24 postoperative hours.

CONCLUSION

According to the findings of this study, aprepitant has demonstrated a greater efficacy in preventing PONV following orthognathic surgery, when compared to ondansetron.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT code: IRCT20211205053279N3), date of registration: 16/12/2022.

Body mass index and weight loss in patients submitted to orthognathic surgery: a prospective study

OBJECTIVE

To compare the body mass index (BMI) and the weight loss (WL) in patients with dentofacial deformities who underwent monomaxillary versus bimaxillary orthognathic surgery.

MATERIALS AND METHODS

This prospective longitudinal study included 69 patients with dentofacial deformities who underwent surgical orthodontic treatment. Patients were divided into two groups according to the type of orthognathic surgery: monomaxillary or bimaxillary. A preoperative nutritional assessment based on BMI was performed; the percentage of involuntary WL between the preoperative and postoperative periods was also calculated. Data were collected at preoperative and 10, 40, and 90 days postoperative (PO). Statistical analysis was performed using SPSS 17.0 (IBM Corp., Armonk, NY, USA), and data are reported with 95% confidence interval.

RESULTS

According to BMI, patients who underwent monomaxillary surgery presented: underweight = 2.6%, normal weight = 51.3%, overweight = 35.9%, and obese = 10.3%. The subjects who underwent bimaxillary surgery presented: normal weight = 43.3%, overweight = 36.7%, and obese = 20%. BMI was similar between the groups at all time points (preoperative, p= 0.237; 10 days PO, p= 0.325; 40 days PO, p= 0.430; and 90 days PO, p= 0.609). All patients lost weight postoperatively, and WL was similar among the PO measurements (p= 0.163).

CONCLUSIONS

Although both monomaxillary and bimaxillary orthognathic surgeries resulted in WL and lower BMI, there was no statistically significant difference in these metrics between the two types of surgery.

Efficacy of an enhanced recovery after surgery pathway to manage pain, nausea and vomiting after head and neck surgeries with free tissue transfer reconstruction

BACKGROUND

Pain and post-operative nausea and vomiting are the main factors that impair the quality of recovery after surgery. Very few reports have analyzed patient-reported outcomes to investigate the efficacy of an enhanced recovery after surgery protocol to alleviate these symptoms after head and neck surgeries with free tissue transfer reconstruction.

METHODS

We investigated post-operative pain and post-operative nausea and vomiting in 47 patients who underwent head and neck surgeries with free tissue transfer reconstruction with enhanced recovery after surgery support between February 2021 and August 2022. Patient-reported outcomes were assessed using the visual analog scale and Japanese version of the Quality of Recovery-40.

RESULTS

Significant increases in the mean visual analog scale scores for pain and post-operative nausea and vomiting were observed only on post-operative Day 1 compared with preoperative values (pain: 3.19 ± 2.78 vs. 1.96 ± 2.42, P = 0.0408; post-operative nausea and vomiting: 1.52 ± 2.09 vs. 0.54 ± 1.37, P = 0.0194). From post-operative Day 2, there were no significant differences between the pre- and post-operative visual analog scale scores, and no significant increases in the incidences of moderate or severe pain and post-operative nausea and vomiting compared with preoperatively. The Japanese version of the Quality of Recovery-40 score for post-operative pain showed no significant deterioration compared with preoperatively, while the Japanese version of the Quality of Recovery-40 score for post-operative nausea and vomiting showed significant deterioration compared with the preoperative value on post-operative Days 2, 4 and 7.

CONCLUSIONS

The visual analog scale and Japanese version of the Quality of Recovery-40 scores for post-operative pain and visual analog scale score for post-operative nausea and vomiting suggested that the enhanced recovery after surgery strategy favorably controlled pain and post-operative nausea and vomiting after head and neck surgeries with free tissue transfer reconstruction. However, as the post-operative Japanese version of the Quality of Recovery-40 score for post-operative nausea and vomiting was lower than the preoperative value, there is still a need for further improvement of the enhanced recovery after surgery pathway.

Postoperative Nausea and Vomiting Prediction: Machine Learning Insights from a Comprehensive Analysis of Perioperative Data

Postoperative nausea and vomiting (PONV) are common complications after surgery. This study aimed to present the utilization of machine learning for predicting PONV and provide insights based on a large amount of data. This retrospective study included data on perioperative features of patients, such as patient characteristics and perioperative factors, from two hospitals. Logistic regression algorithms, random forest, light-gradient boosting machines, and multilayer perceptrons were used as machine learning algorithms to develop the models. The dataset of this study included 106,860 adult patients, with an overall incidence rate of 14.4% for PONV. The area under the receiver operating characteristic curve (AUROC) of the models was 0.60-0.67. In the prediction models that included only the known risk and mitigating factors of PONV, the AUROC of the models was 0.54-0.69. Some features were found to be associated with patient-controlled analgesia, with opioids being the most important feature in almost all models. In conclusion, machine learning provides valuable insights into PONV prediction, the selection of significant features for prediction, and feature engineering.

Comparative Efficacy of Granisetron and Droperidol After Orthognathic Surgery for Prophylaxis of Postoperative Nausea and Vomiting: A Retrospective Study

BACKGROUND

In the fall of 2021, granisetron was approved for postoperative nausea and vomiting (PONV) management in Japan. However, the comparative efficacy of droperidol and granisetron in the field of orthognathic surgery has not been determined.

PURPOSE

We compare the efficacy of droperidol and granisetron for PONV prophylaxis following orthognathic surgery.

STUDY DESIGN, SETTING, SAMPLE

We performed a retrospective cohort study of patients who underwent orthognathic surgery at a single institution from September 2020 to December 2022. Patients who had undergone Le Fort I osteotomy with sagittal split ramus osteotomy or isolated sagittal split ramus osteotomy were included. Patients were divided into three groups; the isolated droperidol (D), isolated granisetron (G), and droperidol with granisetron (DG) groups. General anesthesia was performed using total intravenous anesthesia for all patients; however, droperidol and granisetron were administered at the anesthesiologist's discretion.

PREDICTOR VARIABLE

PONV prophylactic therapy included isolated droperidol, isolated granisetron, and droperidol with granisetron administration.

OUTCOME VARIABLES

Postoperative nausea (PON) and postoperative vomiting (POV) were determined through medical examination within 48 hours following surgery. Secondary outcomes included complications due to droperidol and/or granisetron administration.

COVARIATES

Age, sex, body mass index, Apfel's score, duration of surgery, duration of anesthesia, intraoperative blood loss, and type of surgery.

ANALYSES

Statistical analysis was conducted using Fisher exact test, Mann-Whitney U test with Bonferroni correction for univariate comparison, and modified Poisson regression for comparison of PON and POV prophylactic efficacy for multivariate analyses. P values <.05 were considered statistically significant.

RESULTS

Our study included 218 participants. There were no significant differences in covariates between groups D (n = 111), G (n = 52), and DG (n = 55). No significant difference in PON incidence was observed between groups. However, POV incidence was significantly lower in group DG than group D (relative risk, 0.21; 95% confidence interval, 0.05 to 0.86; P = .03). No significant difference in complication incidence was observed between groups.

CONCLUSIONS AND RELEVANCE

Granisetron was as effective as droperidol for PONV management, while droperidol combined with granisetron was more effective than isolated droperidol for POV management. As compared to the use of each drug separately, their combination was considered safe, with no increase in complication rates.

Enhanced Recovery After Surgery for Head and Neck Oncologic Surgery Requiring Microvascular Reconstruction

It has been demonstrated since the 1990's that surgical outcomes can be improved through protocolized perioperative interventions. Since then, multiple surgical societies have engaged in adopting Enhanced Recovery After Surgery (ERAS) Societal recommendations to improve patient satisfaction, decrease the cost of interventions, and improve outcomes. In 2017, ERAS released consensus recommendations detailing the perioperative optimization of patients undergoing head and neck free flap reconstruction. This population was identified as a high resource demand, oftentimes burdened with challenging comorbidity, and poorly described cohort for which a perioperative management protocol could help to optimize outcomes. The following pages aim to further detail perioperative strategies to streamline patient recovery after head and neck reconstructive surgery.

Predicting early postoperative PONV using multiple machine-learning- and deep-learning-algorithms

OBJECTIVE

PONV reduces patient satisfaction and increases hospital costs as patients remain in the hospital for longer durations. In this study, we build a preliminary artificial intelligence algorithm model to predict early PONV in patients.

METHODS

We use R for statistical analysis and Python for the machine learning prediction model.

RESULTS

Average characteristic engineering results showed that haloperidol, sex, age, history of smoking, and history of PONV were the first 5 contributing factors in the occurrence of early PONV. Test group results for artificial intelligence prediction of early PONV: in terms of accuracy, the four best algorithms were CNNRNN (0.872), Decision Tree (0.868), SVC (0.866) and adab (0.865); in terms of precision, the three best algorithms were CNNRNN (1.000), adab (0.400) and adab (0.868); in terms of AUC, the top three algorithms were Logistic Regression (0.732), SVC (0.731) and adab (0.722). Finally, we built a website to predict early PONV online using the Streamlit app on the following website: ( https://zhouchengmao-streamlit-app-lsvc-ad-st-app-lsvc-adab-ponv-m9ynsb.streamlit.app/ ).

CONCLUSION

Artificial intelligence algorithms can predict early PONV, whereas logistic regression, SVC and adab were the top three artificial intelligence algorithms in overall performance. Haloperidol, sex, age, smoking history, and PONV history were the first 5 contributing factors associated with early PONV.

The Beneficial Effect of Preoperative dexmedetomidine in controlling postoperative pain, nausea, and Vomiting After Orthognathic Surgery: A Triple-blind Randomized Clinical Trial

PURPOSE

Controlling postoperative pain and nausea (PONV) following orthognathic surgery can be challenging. The aim of the study was to assess the efficacy of dexmedetomidine (DEX) in reducing pain and preventing nausea and vomiting in subjects undergoing orthognathic surgery.

METHODS

The authors implemented a triple-blinded, randomized clinical trial. Healthy adults with class III jaw deformity scheduled for bimaxillary orthognathic surgery were included. Subjects were randomized to the DEX or placebo groups. The DEX group received premedication with DEX 1 μg/kg IV over 10 minutes followed by a maintenance dose (0.2 μg/kg/hour). while the placebo group received normal saline. The primary outcome variables were postoperative pain, postoperative nausea, and postoperative vomiting . Pain was assessed using a visual analog scale at 1, 3, 6, 12, 18, and 24 hours, postoperatively). Nausea and vomiting were recorded throughout the postoperative period. Statistical analysis was performed using χ², t test, and repeated measures ANOVA with a P value < .05 considered significant.

RESULTS

A total of 60 consecutive subjects with a mean age of 24.6 ± 3.5 years completed the study. There were 38 females (63.33%) and 22 males (36.66%). The mean visual analog scalewas significantly lower in the DEX group at all time-points (P < .05). There was a significantly greater demand for rescue analgesics in the placebo group compared to the DEX group (P = .01). Fourteen subjects (46.7%) in the placebo group and one subject (3.3%) in the DEX group reported nausea (P < .001). Postoperative vomiting was not observed in any of the subjects.

CONCLUSION

Premedication with DEX can be considered a viable treatment option for reducing postoperative pain and postoperative nausea after bimaxillary orthognathic surgery.

Ambulatory sagittal split ramus osteotomy: strategy for enhanced recovery after surgery

The sagittal split ramus osteotomy (SSRO) has been performed mainly on an inpatient basis because of the duration of anaesthesia and the potential risk of postoperative complications, such as bleeding, pain, nausea, and vomiting. However, advances in both surgical and anaesthetic management have enabled the reduction of these risks and shortened the length of hospital stay. Thus, the SSRO may be feasible even in the ambulatory setting in elective cases. The clinical records of all patients who underwent an outpatient SSRO between August 2011 and September 2020 at Lilla Craniofacial Clinic were reviewed retrospectively. Data on age, sex, duration of surgery, operative procedures, intraoperative bleeding, and admission status were investigated. In total, 143 patients underwent a bilateral SSRO. The SSRO was performed as an isolated procedure in 73 patients and concomitantly with other surgical procedures in the remaining 70 patients. Overall, 142 of the 143 patients were discharged on the day of surgery (99.3%); only one (0.7%) required an overnight stay because of a submental haemorrhage after genioplasty. No emergency hospitalizations or readmissions occurred after discharge. Multimodal perioperative management, both surgical and anaesthetic, facilitated enhanced patient recovery after surgery, and SSRO was performed successfully and safely as an ambulatory procedure.

Risk factors for postoperative nausea and vomiting in patients of orthognathic surgery according to the initial onset time: a cross-sectional study

Background

A high incidence (40-73%) of postoperative nausea and vomiting (PONV) has been reported following orthognathic surgery, and various risk factors have been associated with it. Identifying PONV risk factors based on initial onset time will help establish preventive measures. This study aimed to identify factors that are significantly related to PONV based on the initial onset time after orthognathic surgery.

Methods

This study included 590 patients who underwent orthognathic surgery. Multivariate logistic regression analysis was performed to identify the risk factors that are significantly related to PONV. The objective variables were classified into three categories: no PONV, early PONV (initial onset time: 0-2 h after anesthesia), and late PONV (initial onset time: 2-24 h after anesthesia). The explanatory variables included relevant risk factors for PONV, as considered in previous studies.

Results

Total intravenous anesthesia with propofol was a significant depressant factor for early PONV (adjusted odds ratio [aOR] = 0.340, 95% confidence interval [CI] = 0.209-0.555) and late PONV (aOR = 0.535, 95% CI = 0.352-0.814). The administration of a combination of intraoperative antiemetics (vs. no administration) significantly reduced the risk of early PONV (aOR = 0.464, 95% CI = 0.230-0.961). Female sex and young age were significant risk factors for late PONV (aOR = 1.492, 95% CI = 1.170-1.925 and unit aOR = 1.033, 95% CI = 1.010-1.057, respectively).

Conclusion

We identified factors that are significantly related to PONV based on the initial onset time after orthognathic surgery. Total intravenous anesthesia with propofol significantly reduced the risk of PONV not only in the early period (0-2 h after anesthesia) but also in the late period (2-24 h after anesthesia).

Gastric Negative Pressure Suction Method Reduces the Incidence of PONV after Orthognathic Surgery

Objective

To investigate the effect of gastric negative pressure suction on the incidence of postoperative nausea and vomiting (PONV) in patients undergoing orthognathic surgery.

Methods

A retrospective study of 772 patients who underwent orthognathic surgery from October 2016 to January 2021 was performed, excluding possible confounding factors. The patients were divided into a negative gastric suction group (group 1) and a group without gastric suction (group 2), according to whether gastric suction was used after general anaesthesia. There were 386 patients in each group. The incidence of PONV was compared between the two groups.

Results

The incidence of PONV was 29% in the negative gastric suction group and 58.8% in the non-gastric suction group. The incidence of PONV in the gastric negative pressure suction group was significantly lower than that in the non-gastric negative pressure suction group, and the difference was statistically significant (p &lt; 0.05).

Conclusion

By reducing the risk of perioperative bleeding in orthognathic surgery, gastric negative pressure aspiration can reduce the incidence and operation time of PONV after orthognathic surgery.

Efficacy of gastric aspiration to reduce postoperative vomiting after orthognathic surgery: double-blind randomised clinical trial

Orthognathic surgery is a treatment modality indicated to correct dentofacial deformities. Postoperative vomiting can be associated with multifactorial origin mainly correlated to patient-related symptoms, anaesthetic and surgical factors. Swallowed blood has been related to one of those multifactorial vomiting causes. This present study was to compare the efficacy of gastric aspiration after bimaxillary orthognathic surgery. A double blind randomised clinical trial was carried out and patients were divided in two groups (n = 44/39 respectively). There was statistically significant difference between the control and study groups in the overall incidence of vomiting (p = 0.031) A stratified analysis by sex between both groups was performed demonstrating a four-fold eduction in the odds for vomiting events independent of patient gender (OR = 0.24; 95% CI 0.07 to 0.72). Gastric aspiration after orthognathic surgery can reduce the effects of postoperative vomiting decreasing inpatient period and, consequently, hospitalisation costs.

Cross-sectional Study of PONV Risk Factors for Oral Surgery After Intubated General Anesthesia With Total Intravenous Anesthesia

OBJECTIVE

The incidence of postoperative nausea and vomiting (PONV) after general anesthesia with total intravenous anesthesia (TIVA) was reported to be significantly lower than with volatile inhalational agents (13.3% vs 25%). However, no investigation of PONV risk factors associated with TIVA has ever been reported. This cross-sectional retrospective study aimed to investigate whether known risk factors influenced PONV in intubated general anesthetics utilizing TIVA for dental or oral and maxillofacial surgery.

METHODS

Subjects were 761 patients who underwent dental or oral and maxillofacial surgery under TIVA with propofol, fentanyl, and remifentanil. Univariate and multivariable logistic regression analyses were performed using PONV (within 24 hours) as the dependent variable and previously reported risk factors as independent variables.

RESULTS

Age (odds ratio [OR]: 1.020 per year decrease; 95% confidence interval [CI]: 1.0002-1.0418; P = .047) and female sex (OR: 2.73; 95% CI: 1.60-4.84; P < .001) were positively associated with PONV. Sagittal split ramus osteotomy (SSRO) (OR: 2.28; 95% CI: 1.21-4.33; P = .011) and bimaxillary osteotomy (OR: 5.69; 95% CI: 2.09-15.99; P < .001) were more likely to be associated with PONV than operations that were neither bimaxillary osteotomy nor SSRO. Late PONV (2-24 hours) had an ∼2.7 times higher incidence than early PONV (0-2 hours).

CONCLUSION

These findings suggest further PONV countermeasures, aside from TIVA with propofol and prophylactic antiemetics for orthognathic surgeries especially bimaxillary osteotomy, are needed.

Subramanya Kumar AVS. Efficacy of palonosetron in the management of postoperative nausea vomiting in oral and maxillofacial surgery

Objective:

The objective is to evaluate the efficacy of prophylactic single intravenous dose of palonosetron in the management of postoperative nausea and vomiting (PONV) following oral and maxillofacial surgical interventions performed through an intraoral approach under general anesthesia (GA).

Materials and Methods:

A prospective study was conducted on 100 subjects who underwent intraoral surgical procedures for the management of maxillofacial trauma, pathology, dentofacial anomalies, and deformities under GA. All subjects received a prophylactic single intravenous dose of 0.075 mg palonosetron along with premedication. Predisposing factors for PONV such as patient age, gender, Apfel risk score, history of motion sickness, smoking, type of procedure, and administration of postoperative opioids were taken into consideration. All the patients were monitored for PONV for the 1^st 24 h postoperatively (PO). First, at an interval of 30 min for 1^st 4 h and then at every 2 h interval for next 8 h followed by monitoring every 6 h interval till 24 h. Time and frequency of rescue medication were noted.

Results:

Seventy-nine percentage subjects did not have PONV. 15% subjects had a single episode of vomiting PO which could be attributed to multiple intra oral surgical sites performed as well as longer duration of exposure to anesthetic agents in addition to providing opioid analgesics for the management of postoperative pain. Only 6% subjects needed rescue antiemetic drug. Palonosetron did not show any significant changes in cardiac status and serum profile.

Conclusion:

Palonosetron is effective in the management of PONV for maxillofacial surgical procedures performed through an intraoral approach under GA.

Role of general anesthetic agents in postoperative nausea and vomiting: A review of literature

Postoperative nausea and vomiting (PONV) is considered to be the most unpleasant experience associated with surgery and is believed to be one of the most common reasons for poor patient satisfaction in the postoperative period. It also results in prolonged hospitalization and increased use of resources such as intravenous fluids and drug supplements along with prolonged medical attention, all of which have psychological and financial implications. In addition to this, PONV can result in aspiration, laryngospasm, dehydration, electrolyte disturbances, gastric bleeding, increased intracranial pressure, increased intraocular pressure, and wound dehiscence particularly when the surgical intervention is performed through an intraoral approach. It is a well-known fact that there are many etiological factors as well as predisposing factors for PONV. Hence, this review is intended to evaluate as an individual factor what the role was played by the anesthetic agents used for GA in the incidence of PONV.

Penehyclidine for prevention of postoperative nausea and vomiting following bimaxillary orthognathic surgery: a randomized, double-blind, controlled trial

PURPOSE

To investigate the efficacy and safety of low-dose bolus plus continuous infusion of penehyclidine in preventing postoperative nausea and vomiting (PONV) following bimaxillary surgery.

METHODS

Three hundred fifty-four patients were randomly allocated into three groups. In the Control group, placebo (normal saline) was injected before anesthesia and infused over 48 h after surgery; in the Bolus group, 0.5 mg penehyclidine was injected before anesthesia, whereas placebo was infused after surgery; in the Infusion group, 0.25 mg penehyclidine were injected before anesthesia, another 0.25 mg penehyclidine was infused after surgery. The primary endpoint was the incidence of PONV within 72 h.

RESULTS

A total of 353 patients were included in intention-to-treat analysis. The PONV incidence was 61.0% (72/118) in the Control group, 40.2% (47/117) in the Bolus group, and 28.0% (33/118) in the Infusion group. The incidence was significantly lower in the Bolus group than in the Control group (RR 0.66; 95% CI 0.51-0.86; adjusted P = 0.003) and in the Infusion group than in the Control group (RR 0.46; 95% CI 0.33-0.63; adjusted P < 0.001); the difference between the Infusion and Bolus groups was not statistically significant (RR 0.70; 95% CI 0.48-1.00; adjusted P = 0.144). Emergence agitation occurred more frequently in the Bolus group than in the Control group (36.8% [43/117] vs. 21.2% [25/118], adjusted P = 0.027), but did not differ significantly between the Infusion and Control groups.

CONCLUSIONS

A low-dose bolus plus continuous infusion of penehyclidine was effective in preventing PONV without increasing emergence agitation.

TRIAL REGISTRATION

Clinicaltrials.gov. Identifier: NCT04454866.

Evolution of Hematological Parameters in Patients Undergoing Orthognathic Surgery With a View to Hospital Discharge: A Prospective Study

BACKGROUND

The length of hospital stays of patients undergoing orthognathic surgery depends on related local and systemic factors. Hematological changes resulting from orthognathic surgery, followed up in the postoperative period until hospital discharge, have neither yet been established for specific cases, nor for normal situations. This study aimed to describe the hemodynamic parameters of patients undergoing orthognathic surgery, considering a prediction of hospital discharge. A prospective analytical study was carried out on a sample of convenience for this purpose.

METHODS

The erythrogram, leukogram, and platelet count were assessed 24 and 72 hours after surgery and compared with preoperative values. Intraoperative volume loss was also assessed. Inferential statistical analyses were performed as analysis of variance or Friedman test, paired Wilcoxon test, Mann-Whitney test, and 2-tailed Spearman correlation.

RESULTS

The red blood cell count (mean ± standard deviation [median]); (4.60 ± 0.24 [4.56]), hemoglobin (12.82 ± 1.03 [12.75]), hematocrit (39.51 ± 3.47 [39.60]), and red cell distribution with (32.60 ± 0.88 [33.05]) were higher preoperatively (P < 0.001). Mean corpuscular volume (83.87 ± 5.63 [83.10]), mean corpuscular hemoglobin (27.50 ± 1.47 [28.00]), leukocytes (6262.00 ± 1448.36 [6380.00]). The volume loss varied between 463.87 and 752.13 mL (608.00 ± 144.13 [630.00]).

CONCLUSIONS

The results of the hematological evaluations corroborate the expectation of standard discharge from the hospital, with reflected changes resulting from volume loss and intense postoperative inflammatory response, even under the anti-inflammatory pharmacological effect.

Is Prevention of Postoperative Vomiting Surgery Dependent? A Retrospective Cohort Study of Total Knee Arthroplasty

The study of postoperative nausea and vomiting (PONV) has been ongoing since the early days of general anesthesia. The search for risk factors of PONV and the development of new agents to treat PONV are the two main strategies to combat the adverse side effects of general anesthesia. Female sex, non-smoking status, a history of PONV/motion sickness, and postoperative opioid use are the four independent risk factors for PONV derived after a series of prospective studies, evidence-based systematic reviews, and meta-analyses. The two frequently asked questions that arise ask whether risk factors apply to different clinical settings and whether prevention measures of PONV can be surgery dependent. We conducted a comprehensive review of 665 patients who underwent primary total knee arthroplasty (TKA) between January and December 2019. As nausea is subjective and its measurement is not standardized, postoperative vomiting (POV) was used as a study endpoint. The exclusion criteria were desflurane anesthesia, spinal anesthesia, anesthesia without bispectral index monitoring, and day surgery. Three well-recognized risk factors, consisting of body weight, sevoflurane consumption, and postoperative opioid consumption, were not considered as independent risk factors of POV, while female sex, preoperative adductor canal block (ACB), and dexamethasone were identified as being so in this study. The risk of POV in the female sex was 2.49 times that in the male sex; however, when dexamethasone was used, this risk was reduced by >40% compared with no antiemetic use, and by >50% when patients received preoperative ACB compared with those without the block. The clinical characteristics of our TKA patients—female dominance, old age, and their fairly constant body weights that were distinct from those of other surgical patients—suggested that age may play a crucial role in determining the relative contributions of the different risk factors of POV. We concluded that risk factors of POV are dependent on clinical settings. Based on these results, it is reasonable to speculate that a surgery-dependent plan for the prevention of POV is feasible for patients in similar clinical settings.

A Comprehensive Single-Center Analysis of Postoperative Nausea and Vomiting Following Orthognathic Surgery

BACKGROUND

Postoperative nausea and vomiting (PONV) remains a major clinical end-point for directing enhanced recovery after surgery (ERAS) protocols in facial plastic surgery. This study aimed to identify risk factors for PONV and evaluate strategies for PONV reduction in orthognathic surgery patients.

METHODS

A retrospective cohort study was performed among patients receiving orthognathic surgery at our institution from 2011 to 2018. Patient demographics, surgical operative and anesthesia notes, medications, and nausea/vomiting were assessed for each patient. The amount of opioid analgesia given both perioperatively and postoperatively was recorded and converted into morphine equivalents (MEQ). Stepwise regression analysis was used to identify significant risk factors for PONV. Post hoc analyses were employed to compare PONV among patients based on MEQ dosage and antiemetic prophylaxis regimes.

RESULTS

A total of 492 patients were included; mean age was 23.0 years (range: 13-60); 54.4% were female. The majority of patients received concurrent Le Fort I osteotomy, BSSO, and genioplasty (70.1%). During hospitalization, 59.4% of patients experienced nausea requiring antiemetic medications and 28.4% experienced emesis. Stepwise regression yielded Apfel scores (P = 0.003) and postoperative opioids (P = 0.013) as the strongest predictors of PONV. Post hoc analyses showed that undertreatment with prophylactic antiemetics (based on Apfel) predicted increased PONV (+12.9%, P = 0.020), and that lower postoperative MEQs (<28.0) predicted decreased PONV (-11.8%, P = 0.01).

CONCLUSIONS

The study findings confirm the high incidence of PONV among orthognathic surgical patients and stratify previously reported PONV risk factors. More aggressive utilization of antiemetic medications and decreased dependence on opioid analgesia may decrease nausea/vomiting following orthognathic surgery.

Do oropharyngeal throat packs prevent fluid ingestion during orthognathic surgery?

The oropharyngeal throat pack is commonly used in oral and maxillofacial surgery despite debated evidence regarding its barrier function. The study objectives were to investigate whether the oropharyngeal pack reduces blood ingestion and to evaluate its relationship with postoperative nausea and vomiting (PONV) and throat pain. This was a single-center, parallel group, single-blind randomized controlled trial. Participants undergoing orthognathic surgery, age ≥16 years, were included in the study. After intubation and prior to surgery start, the treatment group received oropharyngeal packing; the control group received no packing. Outcome variables were the quality of gastric contents aspirated by nasogastric tube (bloody or not bloody), PONV, and throat pain (visual analog scale). Thirty patients (treatment n = 15; control n = 15) were randomized and analyzed. There was no difference between the groups in quality of gastric contents (P = 1.00) or incidence of PONV at 2 hours and 24 hours (P = 1.00). Throat pain incidence and severity at 2 hours were both higher in the treatment group, but this was not statistically significant (P = 0.128, P = 0.223). The results indicate that the oropharyngeal pack is not an effective barrier against blood ingestion. Oropharyngeal packs do not improve or worsen PONV, but may increase throat pain.

Benefits of the enhanced recovery after surgery pathway for orthognathic surgery

The enhanced recovery after surgery (ERAS) protocol was designed to improve patient outcomes and decrease complications, opioid use, and postoperative nausea and vomiting (PONV). The aim of this retrospective cohort study was to examine the effectiveness of ERAS protocols implemented in orthognathic surgeries from 2017 to 2018 at the University of Alabama at Birmingham Hospital by measuring opioid use and PONV. Two groups were identified through chart review, a non-ERAS group (traditional) of patients who had surgery without a protocol and an ERAS group of patients who had surgery with the ERAS protocol. The anesthesia and surgical teams followed a standardized protocol for perioperative management. All procedures were performed by a single surgeon and included single- and double-jaw surgeries and adjunctive procedures. The patient charts were analyzed for postoperative opioid consumption (measured in morphine milligram equivalents, MME) and PONV. IBM SPSS Statistics version 26 was used to conduct the statistical analyses. The ERAS group received less opioids during the postoperative period than the control group (31.2 MME vs 54.6 MME, P= 0.002). The ERAS group also had a lower incidence of PONV, with 1.2 episodes of PONV compared to 2.4 episodes in the non-ERAS group (P= 0.008). This study demonstrates that the ERAS protocol is effective in decreasing postoperative opioid consumption and PONV.

Common postoperative complications after general anesthesia in oral and maxillofacial surgery

AIM AND OBJECTIVES

Anesthesia is Greek word meaning loss of sensation, and involves painful invasive procedure to be performed with little distress and no pain to the patient. Postoperative anesthetic complications are very common and duration of surgery is frequently cited as major risk factor for postoperative complications. The recognition and treatment of these complications are important when providing good quality care. The purpose of this study was to evaluate mild, moderate, and severe postoperative complications in patients undergoing maxillofacial surgery under general anesthesia and also determine the safety of general anesthesia in healthy and patients with comorbidities.

SUBJECTS AND METHODS

This prospective study was conducted in the oral and maxillofacial surgery department. Two hundred and twenty patients who were operated under general anesthesia were taken in study. All relevant past medical and dental records were noted and were supported by preformulated questionnaire and was filled preoperatively and after surgery to 12 weeks.

RESULTS

Mild-to-moderate and severe complications were noted. Females showed more complications than males. Most common complications were sore throat, dysphagia, nausea, vomiting, pain, swelling in normal patients, and in patients with comorbidities delayed wound healing, hypertension, and infection were also seen.

CONCLUSION

The use of General Anesthesia is considered safe but it has few risks associated with it and past medical conditions should be evaluated preoperatively.

Impact of preoperative body mass index on perioperative outcomes is optimized by enhanced recovery protocols in laparoscopic radical cystectomy with intracorporeal urinary diversion

Background

We aimed to examine whether body mass index (BMI) had an impact on clinical outcomes of laparoscopic radical cystectomy with intracorporeal urinary diversion. Furthermore, we analyzed the optimization of enhanced recovery protocols (ERPs) on the impact of BMI on clinical outcomes.

Methods

By searching our database, data of 83 consecutive patients were retrospectively collected, including 37 patients with a BMI <24 kg/m² (group A) and 46 patients with a BMI ≥24 kg/m² (group B). The baseline and peri-operative variables of the two groups were compared. Subgroup analysis was conducted for ERPs (11 patients in group A₁, 18 patients in group B₁) and conventional recovery protocols (CRPs; 26 patients in group A₂, 28 patients in group B₂). The primary outcomes were 30-day overall complication rate and ΔALB_min (reduction proportion of minimum albumin). The secondary outcomes were operative time and length of stay.

Results

The baseline variables were similar between the two groups (P>0.05). The 30-day overall complication rate, operative time, and length of stay were similar between the two groups (P>0.05). But post-operative nausea and vomiting (PONV) was higher in group A than in group B (32.4% vs. 8.7%, P=0.014). Group A was associated with lower serum albumin level pre-operatively and on post-operative days 1–3. ΔALB_min was higher in group A than in group B (33.08%±9.88% vs. 27.92%±8.52%, P<0.05). In the subgroup analysis, the CRPs group presented similar results, with group A₂ showing higher PONV rate, lower albumin level pre- and post-operatively, and higher level of reduction proportion (P<0.05). For the ERPs group, the PONV rate, pre-operative albumin level, and reduction proportion were similar between group A₁ and B₁ (P>0.05). Multivariable analysis showed that PONV and CRPs were independently associated with ΔALB_min ≥34% (P<0.05).

Conclusions

BMI had no impact on the 30-day overall complication rate, operative time, and length of stay of patients who underwent laparoscopic radical cystectomy with intracorporeal urinary diversion. BMI <24 kg/m² was associated with higher PONV rate and more albumin loss, both of which could be optimized by ERPs.

Preoperative Ultrasound-Guided Trigeminal Nerve Block in Orthognathic Surgery: A Prospective Study About Its Efficacy of Intraoperative Anesthetic Dosage and Postoperative Analgesia

PURPOSE

Ultrasound-guided trigeminal nerve block is rarely used in orthognathic surgery, and its impact of postoperative analgesia and the auxiliary effect on hypotensive anesthesia have not been fully reported. The purpose of this study is to measure the efficacy of ultrasound-guided trigeminal nerve block on intraoperative anesthetic dosage and postoperative analgesia.

PATIENTS AND METHODS

In this single-blind, prospective, controlled trial, all patients were randomly assigned to 2 groups (n = 21/group): GEA group (general anesthesia) and TNB group (ultrasound-guided trigeminal nerve block [UGTNB] with general anesthesia). The primary variable was postoperative pain (visual analog scale scores, VAS scores) at postoperative 2, 4, 6, 12, and 24 hours. Satisfaction with postoperative pain management during postoperative 24 hours; the number of patients with moderate-to-severe pain (VAS score: >3) at postoperative 2, 4, 6, 12, 24 hours; and the consumption of opioids and nicardipine intraoperatively, etc. were secondary variables. Data were analyzed using the unpaired t, χ2, and Wilcoxon nonparametric tests.

RESULTS

In this study, 40 patients at the Peking University School and Hospital of Stomatology between January 2019 to March 2019 were included with a mean age of 24.13 ± 5.07 for statistical analysis and 37.5% were male. Compared to GEA group, the TNB group had a significantly lower VAS scores at postoperative 6 hours and 12 hours, which were 2[0,2] and 0[0,2], respectively. Furthermore, patients in TNB group were more satisfied with pain management at postoperative 24 hours than patients in GEA group (5[4,5] vs 4[3,5]; P = .03). Statistically less amount of opioids and nicardipine in TNB group were used intraoperatively (P < .01).

CONCLUSION

UGTNB use in orthognathic surgery may improve analgesia in the 24 hours after the operation, additionally, facilitate hypotensive anesthesia with fewer agents and fewer adverse effects postoperatively.

Risk factors for postoperative nausea and vomiting after the removal of impacted third molars: a cross-sectional study

BACKGROUND

A better understanding of the risk factors for postoperative nausea and vomiting (PONV) could improve patient outcomes. This study aimed to analyze the risk factors for PONV and its onset after third molar impaction surgery, and to demonstrate the importance of controlling anesthesia-related factors regardless of patient-specific factors.

METHODS

We included patients who reported nausea and vomiting within 12 h of extubation. Patients with incomplete data, those who could not communicate, and those with gastrointestinal disorders were excluded. We evaluated patient-specific risk factors, and the use of volatile anesthetics and intraoperative fentanyl anesthetic-related factors. Multiple logistic regression analysis was performed taking patient background factors into account.

RESULTS

In total, 182 patients who underwent disimpaction of the third molar under general anesthesia between January 2017 and December 2018 at Nagoya Ekisaikai Hospital, were included. Approximately 12.6% (n = 23) patients experienced PONV, with no significant difference in terms of sex, smoking status, age, and body mass index compared to patients without PONV. Multiple logistic regression analysis revealed no interaction between fentanyl and volatile anesthetics. The major risk factor for PONV was the use of volatile anesthetics. Patients in whom anesthesia was maintained by volatile anesthetics were 13.35 times more likely to have PONV than those in whom total intravenous anesthesia was induced (P < 0.001).

CONCLUSION

Maintenance of anesthesia with volatile anesthetics is a risk factor for PONV.

Reduction in post-operative nausea and vomiting (PONV) by preoperative risk stratification and adherence to a standardized anti emetic prophylaxis protocol in the day-care surgical population

Context

Postoperative nausea (PON) and postoperative vomiting (POV) are the most undesirable morbidity after anaesthesia. There is paucity of data on PONV from the Indian subcontinent.

Aims

We aim to study the prevalence of PON and POV, associated risk factors and the effect of following standardized risk stratification and prophylaxis protocols in the day care patient population.

Settings and Design

This was a prospective cohort study at a tertiary care teaching institute.

Methods and Material

Data from 500 patients undergoing day care surgery over a period of 12 months were analysed. We used the Apfel scoring system for evaluation of risk of post-operative nausea and vomiting (PONV) for each participant. A standard PONV prophylaxis protocol was used intra-operatively.

Statistical analysis used

Data analysis was done using the Mann-Whitney U test, the Chi-square and Fisher's exact test.

Results

The period prevalence of post-operative nausea (PON) and post-operative vomiting (POV) was 2.04% and 2.45%, respectively, in this study. The prevalence of PONV in each risk category was lower than that predicted by the Apfel score due to utilization of a standard anti-emetic prophylactic protocol. We found younger age, previous history of nausea, previous history of vomiting, urological surgeries and alcohol consumption as significant risk factors for postoperative nausea. Longer duration of surgery, previous history of nausea, alcohol consumption and higher BMI were the significant risk factors for postoperative vomiting.

Conclusions

Adherence to preoperative risk stratification and a standard anti-emetic prophylactic protocol can significantly reduce the prevalence of postoperative nausea and vomiting.

Bilateral mandibular block improves pain relief and morphine consumption in mandibular osteotomies: a prospective, randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

The sensory innervation of the lower jaw mainly depends on the third root of the trigeminal nerve, the mandibular nerve (V3). The aim of this single-center, prospective, randomized, double-blind, placebo-controlled study was to evaluate the effectiveness of bilateral V3 block for postoperative analgesia management in mandibular osteotomies.

METHODS

107 patients undergoing mandibular surgery (75 scheduled osteotomies and 32 mandible fractures) were randomized in two groups. A bilateral V3 block was performed in each group, either with ropivacaine 0.75% (block group, n=50) or with a placebo (placebo group, n=57). A postoperative multimodal analgesia was equally provided to both groups. The primary outcome was the cumulative morphine consumption at 24 hours. Secondary outcomes were the occurrence of severe pain and the incidence of postoperative nausea and vomiting (PONV) in the first 24 hours. Data were analyzed on an intention-to-treat basis.

RESULTS

The cumulative morphine consumption at 24 hours was significantly lower in the block group (median 8.0 mg (IQR 2.0-21.3) vs 12.0 mg (IQR 8.0-22.0), p=0.03), as well as the incidence of severe pain during the 24 hours of follow-up (4.0% vs 22.8%, p<0.01). The mandibular block had no impact on the incidence of PONV.

CONCLUSION

Bilateral V3 block for mandibular osteotomies is an effective opioid-sparing procedure. It provided better postoperative analgesia in the first 24 hours, and it did not affect PONV incidence.

TRIAL REGISTRATION NUMBER

NCT02618993.

Evaluation of the Nasopharyngeal Cannula Use After Orthognathic Surgery: Permeability of the Nasal Airways and Discomfort of the Patient With Cleft Lip and Palate

It is believed that the use of the nasopharyngeal cannula can maintain the patent upper airway in the immediate post-operative period of orthognathic surgery. The present study is a randomized clinical trial with the objective of evaluating the difference in the use of the nasopharyngeal cannula in the post-operative period of orthognathic surgery with respect to permeability and discomfort. The sample was composed of 26 individuals with repaired cleft lip and palate randomly distributed in 2 groups with and without nasopharyngeal cannula. The evaluation was composed by Visual Analogue Scale (VAS), test with Altman mirror in 4 pre-operative periods, 6, 24, 30 hours after the operation. Rhinomanometry was also performed, a flow- pressure technique in 2 distinct moments, 6 and 24 hours after surgery. As a result, greater discomfort, greater obstruction as well as a reduction in the area of bilateral minimum nasal cross-section (ASTM) and increased resistance in the group with nasopharyngeal cannula are observed. In the intra-group comparison with the lowest ASTM values, the test group showed a significant difference between the first and the second moments (P = 0.001). It can be concluded that the nasopharyngeal cannula contributes to increase discomfort, worsens airway permeability by decreasing ASTM and increasing nasal resistance. Regarding the length of stay of the nasopharyngeal cannula, it can be said that from 6 hours onwards it does not contribute to the reduction of discomfort, airway permeability and assist in hemostasis.

Effects of throat packs during orthognathic surgery: a double-blind randomized controlled clinical trial

Throat packs are commonly used in maxillofacial surgeries. However, the evidence to support the benefits of their use is controversial. The aim of this study was to evaluate the effectiveness of throat packs in preventing postoperative nausea and vomiting, and their influence on the incidence of sore throat and dysphagia in patients undergoing orthognathic surgery. This was a prospective double-blind randomized study with 54 patients, who were randomized to two groups: with throat pack (n=27) and without throat pack (n=27). Fifty patients (25 in each group) were included in the analysis; 66% female and 34% male, mean age 29.44±8.53 years. Postoperative nausea and vomiting (Kortilla scale), sore throat (visual analogue scale), and dysphagia were evaluated. Statistically significant differences in favour of the without-pack group were found for the variables throat pain at 24hours (P=0.002) and dysphagia at 2 hours (P=0.007) and 24 hours (P<0.001). There was no difference between the groups regarding postoperative nausea and vomiting (P=1.00). The results of this study indicate that throat packs as utilized here do not prevent postoperative nausea and vomiting and are associated with worse sore throats and postoperative dysphagia.

Effect of Body Mass Index on Postoperative Nausea and Vomiting: Propensity Analysis

The impact of body mass index (BMI) on postoperative nausea and vomiting (PONV) is controversial, and few studies have focused on their relationship. We investigated the effects of BMI on PONV, taking into account other PONV risk factors. We analyzed adults over the age of 18 years who received general anesthesia between 2015 and 2019, using propensity score matching. Before propensity score matching, odds ratios (ORs) for PONV were lower for overweight (OR, 0.91; 95% confidence interval (CI), 0.87–0.96; p < 0.0001) or obese patients (OR, 0.77; 95% CI, 0.71–0.84; p < 0.0001) than for normal-BMI patients. After matching, the ORs for PONV of overweight (OR, 0.89; 95% CI, 0.80–0.98; p = 0.016) and obese patients (OR, 0.71; 95% CI, 0.63–0.79; p < 0.0001) were low. However, the ORs of underweight patients did not differ from those of normal-BMI patients, irrespective of matching. Therefore, the incidence of PONV may be lower among adults with a higher-than-normal BMI.

Incidence and risk factors for postoperative nausea and vomiting in orthognathic surgery: a 10-year retrospective study

Objectives

Postoperative nausea and vomiting (PONV) is considered as one of the most incessant and anguishing factors for patients who have surgery under general anesthesia. The occurrence of PONV after orthognathic surgery can lead to dehydration, infection, bleeding at the surgical site, and patient discomfort, all of which leave a patient with a negative impression of anesthesia and surgery. The purpose of this study is to assess the incidence of PONV after orthognathic surgery and to correlate it with factors related to patient, anesthesia, and surgery.

Materials and Methods

A 10-year retrospective survey was done for patients who underwent orthognathic surgery between January 2008 and March 2018. The incidence of PONV was evaluated, correlations with factors related to patient, anesthesia, and surgery were studied, and the duration between the end of surgery and the occurrence of the first episode of PONV was tabulated.

Results

The medical records of 109 patients were screened, out of which 101 satisfied the inclusion criteria. Amongst these patients, 60 patients (59.4%) suffered from PONV. Patient’s sex, induction agent used, intravenous fluids administered intraoperatively, duration and type of surgery, and the presence of a nasogastric tube were seen to have a significant influence on precipitating PONV. It was noted that among the patients who suffered from PONV, 61.7% of them experienced it 48-96 hours after the end of surgery.

Conclusion

Despite the improved anesthetic equipments, drugs, and surgical techniques currently used, the incidence of PONV was high in our study. Certain factors that were seen to influence PONV in this study need to be considered in order to develop an efficacious protocol to reduce PONV in orthognathic surgeries.

The benefit of bilateral inferior alveolar nerve block in managing postoperative nausea and vomiting (PONV) after mandibular osteotomy

INTRODUCTION

The purpose of our study was to evaluate the benefit of bilateral inferior alveolar nerve block (BIANB) in managing postoperative pain, nausea and vomiting and opioid and antiemetic consumption in mandibular osteotomy.

MATERIAL AND METHODS

51 patients operated for bilateral sagittal split osteotomy (BSSO) were included in this prospective randomized controlled, double-blind, superiority trial. In the first group (n = 25), standard protocol was applied (general anesthesia and postoperative multimodal analgesia). The second group (n = 26) received bilateral inferior alveolar nerve block anesthesia at the start of surgery in addition to routine protocol. Postoperative monitoring was conducted every 4 h over the first 24 h and targeted the following criteria: postoperative nausea and vomiting (PONV), the visual analog scale (VAS) for pain, consumption of morphine (cumulative dose) and antiemetic agents, need for removal of guiding elastics.

RESULTS

PONV was significantly lower in the BIANB group (15.4 % VS 40 %, p = 0.049), as were mean VAS scores for pain (1 VS 1.57, p = 0.045) and medians of morphine bolus (8 [6-16] VS 5.5 [1-8], p = 0.033). We found no significant difference in incidence of guiding elastic removal, and antiemetic consumption.

DISCUSSION

The use of BIANB in BSSO improved postoperative patient comfort in terms of PONV and pain. Furthermore, it led to a decrease in opioid consumption. In conclusion, it is an additional therapeutic means of improving patients' postoperative comfort.

A prospective, randomized, double-blind trial to compare body weight-adjusted and fixed doses of palonosetron for preventing postoperative nausea and vomiting in obese female patients

Background

Postoperative nausea and vomiting (PONV) is a common postsurgical complication. Palonosetron is effective for PONV prevention at the usual dose of 75 μg, but the ideal dose for obese patients has not yet been investigated. The aim of this study was to compare body weight-adjusted and fixed doses of palonosetron for preventing PONV in obese female patients.

Materials and methods

We performed a prospective, randomized, double-blind trial involving 80 female patients, aged 18–80 years with an American Society of Anesthesiologists physical status of 2 and 3 and a body mass index (BMI) ≥ 30 kg m^-2 who were scheduled to undergo elective breast surgery. Patients received an intravenous body weight-adjusted dose of palonosetron (1 μg kg ^-1, GI = 40 patients) or a fixed dose of palonosetron (75 μg, GII = 40 patients). All patients received dexamethasone (4 mg). The incidence of PONV, complete response rate (CR), severity of nausea and need for rescue antiemetics and analgesics were assessed at: 0–1 h, 1–6 h, 6–24 h and 24–48 h postoperatively.

Results

The mean (± SD) BMI was 35.0 (±5.2) kg m^-2 for GI and 35.7 (±3.6) kg m^-2 for GII. There was no significant difference between groups in PONV incidence, CR, severity of nausea, and need for rescue antiemetics or analgesics. The incidence of PONV for GI and GII was 15% and 27.5%, respectively, during the first 48 h (P = 0.17).

Conclusions

A body weight-adjusted dose of palonosetron was as effective as 75 μg for preventing PONV for 48 h in obese female patients who underwent breast surgery. Hence, the fixed dose may be preferable to the body weight-adjusted dose.

Prevalence of postoperative nausea and vomiting: A systematic review and meta-analysis

Objective:

Postoperative nausea and vomiting (PONV) is a daily phenomenon, to which less attention has been paid in a variety of surgeries. Despite the individual studies, there is no comprehensive study on the prevalence of PONV. The aim of this study was to determine the global prevalence of PONV.

Materials and Methods:

In this systematic and meta-analysis study, descriptive studies of four databases (PubMed, Web of Science, Scopus, and Google Scholar) were searched for relevant texts from the time they were created until 31 December 2018. The random effects model was used for meta-analysis of studies included. All the steps were carried out by two individuals. Hoy et al.'s tool was used to evaluate its risk bias.

Results:

A total of 23 studies that were performed on 22,683 people from 11 countries were entered into the final phase. The prevalence of PONV, nausea, and vomiting was 27.7%, 31.4%, and 16.8%, respectively. The prevalence of PONV was higher during the first 24 h in European countries.

Conclusion:

Considering the high prevalence of PONV and our goal to better control it, it is necessary to use high cost-effective approaches and recommendations and to educate health caregivers and patients.

Comparison of Sufentanil- and Fentanyl-based Intravenous Patient-controlled Analgesia on Postoperative Nausea and Vomiting after Laparoscopic Nephrectomy: A Prospective, Double-blind, Randomized-controlled Trial

Background: The incidence of postoperative nausea and vomiting (PONV) remains high. The effects of sufentanil for PONV is not firmly confirmed. The aim of this study was to compare the effect of sufentanil- and fentanyl-based intravenous patient-controlled analgesia (IV-PCA) on the incidence of PONV after laparoscopic nephrectomy. Methods: Eighty-six patients were randomly allocated to receive either the sufentanil (n =43) or fentanyl (n =43). IV-PCA was prepared using either sufentanil 3 µg/kg or fentanyl 20 µg/kg, ramosetron 0.3 mg, and ketorolac 120 mg. The primary outcome of was the incidence of PONV during 24 h after post anesthesia care unit (PACU) discharge. The secondary outcomes were the modified Rhodes index and patient satisfaction scores at 24 h after PACU discharge, need for rescue antiemetics, pain score, need for additional analgesics, and cumulative consumption of IV-PCA Results: The incidence of PONV was comparable between the sufentanil and fentanyl groups (64.3% vs. 65%, p = 0.946; respectively). The number of patients who required antiemetics (p = 0.946) and the modified Rhodes index at 24 h after post-anesthesia care unit discharge (p = 0.668) were also comparable in both groups. No significant differences were found in the secondary outcomes, including the analgesic profiles and adverse events between the groups. Conclusions: In conclusion, sufentanil- and fentanyl-based IV-PCA showed similar incidence of PONV with comparable analgesic effects after laparoscopic nephrectomy. Based on these results, we suggest that sufentanil and fentanyl may provide comparable effects for IV-PCA after laparoscopic nephrectomy.

Incidence of postoperative nausea and vomiting is not increased by combination of low concentration sevoflurane and propofol compared with propofol alone in patients undergoing laparoscopic gynecological surgery

Background

The incidence of postoperative nausea and vomiting (PONV) is higher in patients receiving volatile anesthetics than those receiving total intravenous anesthesia (TIVA) with propofol. However, it is unclear whether its incidence is increased when a low concentration of sevoflurane is used in combination with propofol.

Methods

This prospective, randomized, controlled trial enrolled women undergoing laparoscopic gynecological surgery. Patients were randomly assigned to receive general anesthesia either with propofol alone (group P) or with 0.8% sevoflurane and propofol (group SP, n = 36, each group) for maintenance of anesthesia. The incidence of PONV and the number of patients who required antiemetics were compared.

Results

There were no differences in the incidence of PONV and the number of patients who required antiemetics between the P and SP groups.

Conclusions

A combination of 0.8% sevoflurane and propofol to maintain anesthesia does not increase the incidence of PONV compared with TIVA with propofol.

Trial registration

UMIN-CTR UMIN000023647, registered 14 August 2016.