Small dose of propofol combined with dexamethasone for postoperative vomiting in pediatric Moyamoya disease patients: a prospective, observer-blinded, randomized controlled study

Postoperative Nausea and Vomiting in Pediatric Patients

Postoperative nausea and vomiting (PONV), postoperative vomiting (POV), post-discharge nausea and vomiting (PDNV), and opioid-induced nausea and vomiting (OINV) continue to be causes of pediatric morbidity, delay in discharge, and unplanned hospital admission. Research on the pathophysiology, risk assessment, and therapy for PDNV, OINV and pain therapy options in children has received increased attention. Multimodal pain management with the use of perioperative regional and opioid-sparing analgesia has helped decrease nausea and vomiting. Two common emetogenic surgical procedures in children are adenotonsillectomy and strabismus repair. Although PONV risk factors differ between adults and children, the approach to decrease baseline risk is similar. As PONV and POV are frequent in children, antiemetic prophylaxis should be considered for those at risk. A multimodal approach for antiemetic and pain therapy involves preoperative risk evaluation and stratification, antiemetic prophylaxis, and pain management with opioid-sparing medications and regional anesthesia. Useful antiemetics include dexamethasone and serotonin 5-hydroxytryptamine-3 (5-HT3) receptor antagonists such as ondansetron. Multimodal combination prophylactic therapy using two or three antiemetics from different drug classes and propofol total intravenous anesthesia should be considered for children at high PONV risk. "Enhanced recovery after surgery" protocols include a multimodal approach with preoperative preparation, adequate intravenous fluid hydration, opioid-sparing analgesia, and prophylactic antiemetics. PONV guidelines and management algorithms help provide effective postoperative care for pediatric patients.

Assessment of P values for demographic data in randomized controlled trials

In a large number of randomized controlled trials, researchers provide P values for demographic data, which are commonly reported in table 1 of the article for the purpose of emphasizing the lack of differences between or among groups. As such, the authors intend to demonstrate that statistically insignificant P values in the demographic data confirm that group randomization was adequately performed. However, statistically insignificant P values do not necessarily reflect successful randomization. It is more important to rigorously establish a plan for statistical analysis during the design and planning stage of the study, and to consider whether any of the variables included in the demographic data could potentially affect the research results. If a researcher rigorously designed and planned a study, and performed it accordingly, the conclusions drawn from the results would not be influenced by P values, regardless of whether they were significant. In contrasts, imbalanced variables could affect the results after variance controlling, even though whole study process are well planned and executed. In this situation, the researcher can provide results with both the initial method and a second stage of analysis including such variables. Otherwise, for brief conclusions, it would be pointless to report P values in a table simply listing baseline data of the participants.

Antiemetic effect of propofol administered at the end of surgery in laparoscopic assisted vaginal hysterectomy

Background

Postoperative nausea and vomiting (PONV) commonly occur after general anesthesia, especially in women. In this study, we evaluated the antiemetic efficacy of propofol administered at the end of surgery in highly susceptible patients undergoing a laparoscopy-assisted vaginal hysterectomy.

Methods

A total of 107 women undergoing a laparoscopy-assisted vaginal hysterectomy under general anesthesia were enrolled for this prospective, double-blind, randomized study. Fifteen minutes before the end of surgery, all patients received 50 µg fentanyl and 1 of following 3 doses; 0.5 mg/kg of propofol (propofol 0.5 group), 1 mg/kg of propofol (propofol 1.0 group), and normal saline (control group). All patients received intravenous patient-controlled analgesia (PCA). Emergence time, a visual analog scale for pain and nausea, duration of postanesthesia care unit (PACU) stay, and frequency of antiemetic use were recorded at 0-2, 2-24, and 24-48 hours postoperatively.

Results

The incidence of nausea significantly lower in the propofol 0.5 and propofol 1.0 groups than in the control group (12.1 vs 14.7 vs 40%). During the first postoperative 2 hours, antiemetics were less frequently administered in the propofol 0.5 and propofol 1.0 groups than in the control group (3.0 vs 5.9 vs 22.5%). Emergence time was slightly longer in the propofol 0.5 and propofol 1.0 groups than in the control group, but there was no significant difference in PACU stay time was observed between the 3 groups.

Conclusions

The results of this study suggest that low-dose propofol administration at the end of surgery may effectively reduce the incidence of PONV within 2 hours postoperatively in highly susceptible women undergoing a laparoscopiy-assisted vaginal hysterectomy and receiving opioid-based PCA.