AIM: To compare the efficacy and safety of sedation protocols for endoscopic submucosal dissection (ESD) between dexmedetomidine-remifentanil and propofol-remifentanil. METHODS: Fifty-nine patients scheduled for ESD were randomly allocated into a dexmedetomidine-remifentanil (DR) group or a propofol-remifentanil (PR) group. To control patient anxiety, dexmedetomidine or propofol was infused to maintain a score of 4-5 on the Modified Observer’s Assessment of Alertness/Sedation scale. Remifentanil was infused continuously at a rate of 6 μg/kg per hour in both groups. The ease of advancing the scope into the throat, gastric motility grading, and satisfaction of the endoscopist and patient were assessed. Hemodynamic variables and hypoxemic events were compared to evaluate patient safety. RESULTS: Demographic data were comparable between the groups. The hemodynamic variables and pulse oximetry values were stable during the procedure in both groups despite a lower heart rate in the DR group. No oxygen desaturation events occurred in either group. Although advancing the scope into the throat was easier in the PR group (“very easy” 24.1% vs 56.7%, P = 0.010), gastric motility was more suppressed in the DR group (“no + mild” 96.6% vs 73.3%, P = 0.013). The endoscopists felt that the procedure was more favorable in the DR group (“very good + good” 100% vs 86.7%, P = 0.042), whereas patient satisfaction scores were comparable between the groups. En bloc resection was performed 100% of the time in both groups, and the complete resection rate was 94.4% in the DR group and 100% in the PR group (P = 0.477). CONCLUSION: The efficacy and safety of dexmedetomidine and remifentanil were comparable to propofol and remifentanil during ESD. However, the endoscopists favored dexmedetomidine perhaps due to lower gastric motility.

Craniotomy patients have a high incidence of postoperative nausea and vomiting (PONV). This prospective, randomized, double-blind, multi-center study was performed to evaluate the efficacy of prophylactic ramosetron in preventing PONV compared with ondansetron after elective craniotomy in adult patients. A total of 160 American Society of Anesthesiologists physical status I–II patients aged 19–65 years who were scheduled to undergo elective craniotomy for various intracranial lesions were enrolled in this study. All patients received total intravenous anesthesia (TIVA) with propofol and remifentanil. Patients were randomly allocated into three groups to receive ondansetron (4 mg; group A, n = 55), ondansetron (8 mg; group B, n = 54), or ramosetron (0.3 mg; group C, n = 51) intravenously at the time of dural closure. The incidence of PONV, the need for rescue antiemetics, pain score, patient-controlled analgesia (PCA) consumption, and adverse events were recorded 48 h postoperatively. Among the initial 160 patients, 127 completed the study and were included in the final analysis. The incidences of PONV were lower (nausea, 14% vs. 59% and 41%, respectively; P < 0.001; vomiting, P = 0.048) and the incidence of complete response was higher (83% vs. 37% and 59%, respectively; P < 0.001) in group C than in groups A and B at 48 h postoperatively. There were no significant differences in the incidence of PONV or need for rescue antiemetics 0–2 h postoperatively, but significant differences were observed in the incidence of PONV and complete response among the three groups 2–48 h postoperatively. No statistically significant intergroup differences were observed in postoperative pain, PCA consumption, or adverse events. Intravenous administration of ramosetron at 0.3 mg reduced the incidence of PONV and rescue antiemetic requirement in craniotomy patients. Ramosetron at 0.3 mg was more effective than ondansetron at 4 or 8 mg for preventing PONV in adult craniotomy patients. Clinical Research Information Service (CRiS) Identifier: KCT0000320 . Registered 9 January 2012.

Moderate to deep sedation has been recommended during endoscopic submucosal dissection (ESD). However, it is often accompanied by adverse events such as respiratory depression or aspiration pneumonia. This study investigated the respiratory complications and ESD outcomes of two sedation protocols: moderate sedation with analgesic supplementation (MSAS) and analgesia targeted light sedation (ATLS). The clinical data of 293 patients who underwent ESD between May and December 2012 were reviewed. During the first 4 months, 155 patients were managed by moderate sedation [Modified Observer Assessment of Alertness/Sedation (MOAA/S) at 2-3] with the MSAS protocol. During the latter period, 138 patients were managed using the ATLS protocol (MOAA/S at 4-5). For both protocols, propofol and remifentanil were infused for sedation and pain control, respectively. The ATLS protocol required less propofol [22.9 (sd 17.3) vs 88.1 (44.0) µg kg(-1) min(-1), P<0.001] and more remifentanil [6.8 (sd 3.1) vs 4.9 (3.0) µg kg(-1) hr(-1), P<0.001] than the MSAS protocol. The desaturation events during the procedure occurred significantly less often (2.2 vs 12.9%, P=0.001) and recovery was significantly faster [19.7 (sd 4.8) vs 27.9 (16.0) min, P<0.001] with the ATLS protocol than with the MSAS protocol. The incidence of aspiration pneumonia with the ATLS protocol was 1.4% compared with 5.2% with the MSAS protocol (P=0.109). There were no differences in outcomes and complications of ESD. The ATLS protocol reduced the incidence of desaturation events without affecting ESD performance compared with the MSAS protocol. There was also a trend towards a low incidence of aspiration pneumonia with the ATLS protocol.

Background: Postoperative nausea and vomiting (PONV) is a common complication after surgery, which increases physical and psychological discomfort and delays recovery. The aim of this study was to test the hypothesis that ramosetron is comparable to ondansetron for the treatment of established PONV after laparoscopic surgery using a prospective, randomized, double-blinded, noninferiority study. Methods: Patients who had at least two risk factors of PONV and underwent laparoscopic surgery under general anesthesia were assessed for eligibility. Patients who developed PONV within the first 2 h after anesthesia received ondansetron (4 mg) or ramosetron (0.3 mg) intravenously in a randomized double-blind manner. Patients were then observed for 24 h after drug administration. The incidence of nausea and vomiting, severity of nausea, rescue antiemetic necessity, and adverse effects at 0–2 or 2–24 h after drug administration was evaluated. The primary endpoint was the rate of patients exhibiting a complete response, defined as no emesis and no further rescue antiemetic medication for 24 h after drug administration. Results: Among the 583 patients, 210 (36.0%) developed PONV and were randomized to either the ondansetron (n=105) or ramosetron (n=105) group. Patient’s characteristics were similar between the groups. The complete response rate was 44.1% in the ondansetron group and 52.9% in the ramosetron group after 24 h of initial antiemetic administration. The incidence of adverse events was not different between the groups. Conclusion: We found evidence to support the noninferiority of ramosetron (0.3 mg) compared to ondansetron (4 mg) for the treatment of established PONV in moderate to high-risk patients undergoing laparoscopic surgery.

Shin S, et al. J Korean Med Sci. 2018 Jan;33(9):e46. https://doi.org/10.3346/jkms.2018.33.e46