Background: Although programmed intermittent epidural bolus (PIEB) is effective for labor analgesia, an appropriate flow rate has not been established. Therefore, we investigated the analgesic effect based on different epidural injection flow rates.Methods: Nulliparous women scheduled for spontaneous labor were enrolled in this randomized trial. After injection of intrathecal 0.2% ropivacaine 3 mg with fentanyl 20 μg, participants were randomized to three study groups. Epidural analgesics, 10 ml during one hour, were administered with patient controlled epidural analgesia as follows (0.2% ropivacaine 60 ml, fentanyl 180 μg, and 0.9% saline 40 ml): continuous (n = 28, 10 ml/h for continuous infusion), PIEB (n = 29, 240 ml/h for bolus infusion of 10 ml), or manual (n = 28, 1200 ml/h for bolus injection of 10 ml). The primary outcome was hourly consumption of the epidural solution. The time interval between labor analgesia and the first breakthrough pain was investigated.Results: The median (Q1, Q3) hourly consumption of epidural anesthetics was significantly different among the groups (continuous: 14.3 [8.7, 16.9] ml, PIEB: 9.4 [6.2, 9.8] ml, manual: 8.6 [7.6, 9.9] ml; P < 0.001). The time to breakthrough pain for the PIEB group was longer than that for the other groups (continuous: 78.5 [35.8, 185.0] min, PIEB: 200.0 [88.5, 441.5] min, manual: 60.5 [37.3, 162.0] min, P = 0.027).Conclusions: PIEB, with a low-flow rate, provided more adequate labor analgesia than a continuous epidural infusion or manual injection with a high-flow rate.

The incidence of hyperkalemia (>5.5 mEq/L) or high blood potassium (5–5.5 mEq/L) during living-donor liver transplantation (LDLT) is reported to be more than 10%. It occurs more frequently in the early post-reperfusion period and is a major cause of post-reperfusion arrhythmia and cardiac arrest. Unlike deceased-donor liver transplantation, the pattern of blood potassium changes immediately after reperfusion has not been described in LDLT. From January 2021 to March 2021, fifteen consecutive patients were enrolled. Baseline blood potassium was measured from blood samples obtained 10-min (T_-10) and immediately before (T₀) reperfusion. During the first 5 min after reperfusion, blood potassium measurements were conducted every one minute (T₁–T₅). The blood potassium levels at T_-10 and T₀ were 3.8 ± 0.4 and 3.9 ± 0.4 mEq/L, respectively. After reperfusion, mean increases (95% CI) in blood potassium from T_-10 and T₀ were 0.5 (0.4–0.6) and 0.4 (0.3–0.5) mEq/L, respectively. Blood potassium peaked at T₁, returned to baseline at T₃, and fell below the baseline at T₅. Peak blood potassium after reperfusion showed strong correlations with blood potassium measured at T_-10 (p < 0.001) and T₀ (p < 0.0001). These findings can support the establishment of future research plans and perioperative management of blood potassium in LDLT.

Despite rapid advancements in laparoscopic surgical techniques and perioperative management, postoperative pain remains a significant clinical issue. We examined the analgesic efficacy of nefopam as an adjuvant in patient-controlled analgesia (PCA) for acute postoperative pain in patients undergoing laparoscopic colorectal cancer surgery. We retrospectively analyzed the medical records of 120 patients who did or did not receive 80 mg of nefopam as an adjuvant in fentanyl PCA; they were allocated to the nefopam (n = 60) or non-nefopam group (n = 60). The demographic, clinical, and anesthetic data, with data on pain severity and opioid administration at the postoperative anesthesia care unit (PACU) on postoperative days (PODs) 1, 3, and 5, were compared between the groups. The pain score and opioid administration did not differ at the PACU or on PODs 1, 3, or 5. The day of PCA discontinuation, time to pass flatus, length of the hospital stay, and incidence of nausea/vomiting, dizziness, and headache also did not differ between the groups. Fentanyl PCA with 80 mg of nefopam as an adjuvant did not have a superior analgesic effect after laparoscopic colorectal cancer surgery.

Background: Oxygen demand–supply mismatch is supposed to be one of the major causes of myocardial injuries after noncardiac surgery (MINS). Impaired tissue oxygenation during the surgery can lead to intraoperative hyperlactatemia. Therefore, we aimed to evaluate the relationship between intraoperative lactate level and MINS. Methods: A total of 1905 patients divided into groups according to intraoperative hyperlactatemia: 1444 patients (75.8%) into normal (≤2.2 mmol/L) and 461 patients (24.2%) into hyperlactatemia (>2.2 mmol/L) groups. The primary outcome was the incidence of MINS, and all-cause mortality within 30 days was compared. Results: In the crude population, the risks for MINS and 30-day mortality were higher for the hyperlactatemia group than the normal group (17.7% vs. 37.7%, odds ratio [OR]: 2.83, 95% confidence interval [CI]: 2.24–3.56, p < 0.001 and 0.8% vs. 4.8%, hazard ratio [HR]: 5.86, 95% CI: 2.9–12.84, p < 0.001, respectively). In 365 propensity score-matched pairs, intraoperative hyperlactatemia was consistently associated with MINS and 30-day mortality (21.6% vs. 31.8%, OR: 1.69, 95% CI: 1.21–1.36, p = 0.002 and 1.1% vs. 3.8%, HR: 3.55, 95% CI: 1.71–10.79, p < 0.03, respectively). Conclusion: Intraoperative lactate elevation was associated with a higher incidence of MINS and 30-day mortality.

Current guidelines recommend delaying noncardiac surgery for 6 months after drug eluting stent implantation. However, this recommendation is largely based on limited evidence and various event definitions. Whether early surgery within 6 months of coronary stent implantation increases myocardial injury in patients with normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) has not yet been investigated. This retrospective study assessed patients who received coronary stent implantation and underwent noncardiac surgery (vascular, abdominal, or thoracic) between 2010 and 2017 with normal preoperative hs-cTnI (n = 186). Patients were divided into early (within 6 months of PCI) and late (after 6 months of PCI) groups. The primary endpoint was the incidence of myocardial injury as diagnosed by hs-cTnI within 3 days post-operation. The secondary outcomes were myocardial infarction, stent thrombosis, emergent coronary revascularization, major bleeding (bleeding requiring transfusion or intracranial bleeding), stroke, renal failure, heart failure, or death within 30 days post-operation. Inverse probability treatment weighting (IPTW) was carried out to adjust for the intergroup baseline differences. Myocardial injury occurred in 28.6% (8/28) and 27.8% (44/158) of the early and late groups, respectively, with no difference between groups (odds ratio [OR] 1.067, 95% confidence interval [CI] 0.404, 2.482; p = 0.886). Secondary outcomes did not differ between the groups. IPTW analysis also showed no differences in myocardial injury and secondary outcomes between the groups. In conclusion, early surgery within 6 months after coronary stent implantation did not increase the incidence of myocardial injury in patients with normal preoperative hs-cTnI.

Objectives: The indications for endoscopic submucosal dissection (ESD) for gastric adenoma and gastric cancer have expanded, leading to an increase in the number of patients with high procedural complexity. Post-ESD perforations prolong hospital stays and increase costs. However, no studies have focused on detecting micro-perforations during ESD. This study aimed to identify signs of perforation using abdominal ultrasound during gastric ESD. Materials and methods: This pilot study analyzed 50 patients who underwent abdominal ultrasound (VScan Air™, GE Healthcare) during ESD at Samsung Medical Center (March 2023–July 2024). Perforation was assessed via ultrasound, and post-procedure X-rays were performed for three days to detect free air. Results: Among 50 patients (median age 60, 76.1% male), the median procedure time was 60 min. Lesions were most common in the antrum (30.4%) and lesser curvature (17.4%). Pathology revealed 32.6% well-differentiated and 10.9% moderately differentiated adenomas, with 15.2% showing high-grade dysplasia. Free air was detected in three patients after procedures involving the body wall of the stomach. Abdominal US showed indirect signs of perforation, including an abnormal peritoneal line, hyperechoic shadowing, and an absence of normal gas patterns, confirmed by X-ray. Conclusions: Abdominal US is a simple, useful tool for rapid detection of perforation during ESD, enabling timely intervention. Further multicenter studies are needed to confirm these findings.