Anesthesiology Research and Practice

Purpose. Preoperative oral carbohydrate (CHO) is a rapid postoperative rehabilitation protocol that improves perioperative outcomes and is widely used in adult surgical patients. However, pregnant women are excluded because of the possibility of aspiration due to delayed gastric emptying. This meta-analysis was conducted to evaluate the efficacy of preoperative oral CHO in elective cesarean section. Methods. PubMed, Embase, Web of Science, and the Cochrane Library were searched from inception to July 2023. Randomized controlled trials were included. The risk of bias was assessed using the Cochrane tool. Risk ratios and 95% confidence intervals were calculated. Meta-analysis was performed using random-effects models to estimate risk ratios and mean differences (MDs) with 95% confidence intervals (CIs). The outcomes included thirst and hunger scores, incidence of vomiting and nausea, time to flatus, and homeostatic model assessment of insulin resistance (HOMA-IR). Results. A total of nine studies with 1211 patients were included in the analysis. The levels of thirst and hunger were evaluated using a 10-point visual analog scale, with 0 representing the best and 10 representing the worst. The severity of hunger (weighted mean difference (WMD: −2.34, 95% CI: −3.13 to −1.54), time to flatus (WMD: −3.51 hours, 95% CI: −6.85 to −0.17), and HOMA-IR (WMD: −1.04, 95% CI: −1.31 to −0.77) were significantly lower in the CHO group compared to the control group. However, there were no significant differences in the severity of thirst or the incidence of vomiting and nausea between the CHO and control groups. Conclusion. Preoperative oral CHO during cesarean section alleviates thirst and hunger, shortens the time of postoperative flatus, and reduces HOMA-IR. However, the available evidence is insufficient to reach a clear consensus on the benefits or harms of preoperative oral CHO during cesarean section. Therefore, it is premature to make a definitive recommendation for or against its routine use.

Background. In recent years, the attention paid to colorectal cancer (CRC) surgery and postoperative analgesia has increased. Objective. The objective of the current study was to compare the impact of ultrasound-guided erector spinae plane block (ESPB) and transmuscular quadratus lumborum block (TQLB) upon providing relief to patients with postoperative pain who underwent laparoscopic resection for CRC. Methods. In this prospective, comparative, and randomized study, the authors considered a total of 60 patients who chose to undergo laparoscopic resection for colorectal cancer. The total number of patients was randomly divided into two groups (such as ESPB and TQLB) so that each group had a total of 30 patients. For the former group, i.e., the ESPB group, 20 ml of 0.25% bupivacaine was administered at each side for bilateral ultrasound-guided erector spinae plane block, while the latter group received the same dose of medicine for bilateral ultrasound-guided transmuscular quadratus lumborum block (TQLB). The researchers recorded the first time to rescue an analgesic, the whole amount of rescue analgesia under consumption in the first 24 hours after the surgical procedure, and associated adverse events. Results. Among the groups considered, the ESPB group took a significantly lengthy time to raise a first request for rescue analgesic (280 ± 15.5 min) in comparison with the TQLB group (260 ± 13.8 min). Likewise, the consumption of overall nalbuphine was remarkably lesser in the ESPB group during the first 24 hours (24 ± 2.5 mg) compared to the TQLB group (30.5 ± 1.55 mg). Conclusion. The analgesic efficacy of ESPB was better when compared to TQLB in terms of time to rescue analgesia and overall opioid consumption during the first 24 hours. This study was registered at ClinicalTrials.gov on 10/10/2022 (registration number: NCT05574283).

Background. In regional anesthesia, the efficacy of novel blocks is typically evaluated using randomized controlled trials (RCTs), the findings of which are aggregated in systematic reviews and meta-analyses. Systematic review authors frequently point out the small sample size of RCTs as limiting conclusions from this literature. We sought to determine via statistical simulation if small sample size could be an expected property of RCTs focusing on novel blocks with typical effect sizes. Methods. We simulated the conduct of a series of RCTs comparing a novel block versus placebo on a single continuous outcome measure. Simulation analysis inputs were obtained from a systematic bibliographic search of meta-analyses. Primary outcomes were the predicted number of large trials (empirically defined as N ≥ 256) and total patient enrollment. Results. Simulation analysis predicted that a novel block would be tested in 16 RCTs enrolling a median of 970 patients (interquartile range (IQR) across 1000 simulations: 806, 1269), with no large trials. Among possible modifications to trial design, decreasing the statistical significance threshold from to was most effective at increasing the total number of patients represented in the final meta-analysis, but was associated with early termination of the trial sequence due to futility in block vs. block comparisons. Conclusion. Small sample size of regional anesthesia RCTs comparing novel block to placebo is a rational outcome of trial design. Feasibly large trials are unlikely to change conclusions regarding block vs. placebo comparisons.

Background. The postorthognathic surgery patients experienced moderate to severe pain and could be at risk for opioid-related side effects. The aim of this study was to evaluate the efficacy of a single dose of intravenous paracetamol to control postorthognathic surgery pain and reduce opioid consumption. Methods. The patients were randomized into two groups. The study group received intravenous paracetamol and the control group received a placebo immediately postoperation. The visual analogue pain scale (VAS) at 1-, 4-, 8-, 12-, 16-, 20-, and 24 -h postoperatively, morphine consumption, side effects from morphine, and patient satisfaction were analyzed. Results. Sixty-two patients (thirty-one patients in each group) were included. The postoperative VAS in the study group was significantly lower than those in the control group ( value <0.001) at all time points. The total postoperative morphine consumption in the study group (45.1 ± 21.2 mcg/kg) was significantly lower compared with the control group (136.5 ± 49.9 mcg/kg) ( value <0.001). Patient satisfaction was significantly higher in the study group (4.7 ± 0.5 out of 5 points) than in the control group (4.1 ± 0.7 out of 5 points) ( value <0.001). The incidence of nausea and vomiting was significantly lower in the study group compared with the control group ( value <0.001 and 0.002, respectively). Conclusion. A single dose of intravenous paracetamol as part of multimodal analgesia was effective for postorthognathic surgery pain. It provided significant benefits to patients, including reduced pain scores, decreased opioid consumption, reduced nausea and vomiting, and improved satisfaction. This trial is registered with TCTR20210908002.

Background. Zoster-associated pain (ZAP) is often refractory to conventional treatments and can seriously affect patients’ physical and mental health. High-voltage pulsed radio frequency (H-PRF) is a new method for treating ZAP with pulse voltages above 60 V or even up to 100 V. The purpose of this paper was to conduct a systematic review and meta-analysis to evaluate the efficacy of H-PRF in the management of ZAP. Methods. PubMed, Embase, and the Cochrane library were searched from their inception to June 2022 to identify controlled trials which evaluated the effectiveness of H-PRF compared with standard PRF and sham operations. The primary outcome was pain scores at different treatment times. The secondary outcomes included SF-36 scores, rescue analgesic dose, and side effects. Results. We reviewed 6 randomized controlled trials involving 428 patients. There was no significant difference between the H-PRF and standard PRF pain scores at 1 week after surgery and the sham operation group at 1 month. At 1, 3, and 6 months, the H-PRF group had better pain score than the standard PRF group, and at 3 months, the pain score was better than the sham operation group. The H-PRF group showed improvement in the SF-36 score, and there were no significant complications in the H-PRF group. Conclusions. H-PRF is an effective and safe treatment method that has better effects in relieving pain and improving the quality of life and physical and mental health. Although H-PRF provides pain relief rates comparable to those of the control group in the early stages, it remains the preferred and alternative treatment for relieving herpes zoster-related pain.

Background. Postpartum hemorrhage (PPH) is a serious postdelivery condition with a high incidence of morbidity and mortality for women who undergo childbirth with or without a caesarean section. Melatonin has been suggested to increase the contractility of myometrium and reduce the pain score postoperatively, therefore it is believed that the use of melatonin before surgery may decrease blood loss, reduce pain score, and decrease the need for postoperative opioids. Objectives. The main objectives of this study are focused on the investigation of melatonin as a premedication agent to reduce blood loss and decrease pain score postoperatively in patients undergoing cesarean section under spinal anesthesia. Methods. 80 patients were scheduled for spinal anesthesia-based cesarean sections and randomly assigned to two groups, melatonin group (M) 40 patients and placebo group (P) 40 patients to receive either 10 mg of sublingual melatonin or a placebo of 90 minutes preoperatively. Hemoglobin levels were been measured preoperative and 12 hrs. Postoperatively, blood loss volume was calculated by measuring both the weight of used materials before and after the surgery and the volume sucked in the suction bottle after placental delivery. Postoperative visual pain score and analgesic requirements were used to evaluate pain levels. Results. Analyzed collected data showed a significant decrease in blood loss in the melatonin group in comparison with the placebo group as measured by the hemoglobin level. On the other hand, there is a significant decrease in pain score and analgesia requirement with the melatonin group compared to the placebo group. Conclusion. Melatonin is a promising premedication drug that has a significant impact on postpartum hemorrhage by reducing blood loss and pain levels of mothers who have undergone C-sections.