Epidural analgesia has been effective for postoperative pain control, but its use has declined owing to adverse effects, such as motor blockade and delayed recovery. However, in obstetric anesthesia, it remains the gold standard of care, especially with the development of programmed intermittent epidural bolus (PIEB), which delivers boluses of local anesthetic at fixed intervals to improve drug spread and reduce motor blockade. Clinical studies on labor analgesia have demonstrated that PIEB offers superior analgesia, lower anesthetic consumption, and higher maternal satisfaction than continuous epidural infusion. These advantages align well with Enhanced Recovery after Surgery protocols, supporting early mobilization and opioid-sparing strategies. While most evidence comes from obstetric settings, emerging data suggest that PIEB also benefits perioperative patients and holds promise for broader surgical applicability. This review explores current knowledge and emerging evidence regarding the potential application of PIEB beyond labor analgesia.

Background:The intraoperative co-administration of lidocaine and dexmedetomidine has been proposed as an opioid-sparing strategy; however, its effectiveness as an intraoperative multimodal analgesia (MMA) strategy remains unclear. We evaluated its effect on postoperative opioid consumption in patients undergoing major laparoscopic gynecologic surgery. Methods:We conducted a randomized controlled trial comparing intraoperative placebo with lidocaine-dexmedetomidine co-administration in patients undergoing major laparoscopic gynecologic surgery within a standardized Enhanced Recovery after Surgery (ERAS) pathway. Patients were assigned to receive intraoperative placebo or lidocaine at 1.5 mg/kg/h co-administered with dexmedetomidine at either 0.4 or 0.7 μg/kg/h. The primary outcome was 24-h cumulative opioid consumption. Results:Twenty-four-hour cumulative opioid consumption differed significantly between the groups (P = 0.004). Median morphine-equivalent dose was 16.6 mg (12.1, 22.3) in the control group, 11.3 mg (8.1, 19.5) in the lidocaine-dexmedetomidine 0.4 group, and 11.1 mg (6.8, 16.5) in the 0.7 group, corresponding to relative reductions of 32% and 33% in median consumption, respectively. Both dexmedetomidine doses (0.4 and 0.7 μg/kg/h), when co-administered with lidocaine, were associated with significantly lower opioid consumption than the control group, with no significant differences between the two doses. Pain scores during mobilization were lower in both treatment groups during the first 48 h postoperatively, without an increase in adverse events. Conclusion:Intraoperative co-administration of lidocaine and dexmedetomidine effectively reduced postoperative opioid consumption and pain during mobilization as an intraoperative MMA strategy within an ERAS pathway. The higher dexmedetomidine dose provided no additional opioid-sparing benefit during the first 24 postoperative hours.

Background: Effective perioperative analgesia is essential to prevent abrupt changes in cerebral blood flow following carotid endarterectomy (CEA). We aimed to evaluate whether multimodal analgesia, including intermediate cervical plexus block (CPB), reduces 24 h postoperative opioid consumption compared with local infiltration. Methods: This randomized, observer-blinded study included 40 patients undergoing CEA. Patients were randomly allocated to either the multimodal group (multimodal analgesia with intermediate CPB, n = 20) or the control group (local infiltration, n = 20). The primary outcome was 24 h intravenous (IV) opioid conversion to IV morphine equivalents. Secondary outcomes included pain scores at rest and during motion, time to first opioid use, hypertension incidence, antihypertensive use, postoperative nausea/vomiting, satisfaction with pain management, quality of first-night sleep, Korean version of the Quality of Recovery-15 (QoR-15K) scores, complications, cerebral hyperperfusion syndrome, and intraoperative analgesia nociception index values. Results: In the intention-to-treat analysis, 24 h postoperative opioid consumption was 13.3 (6.7, 20.0) mg and 10.0 (6.7, 13.3) mg in the control and multimodal groups, respectively, with no significant difference (P = 0.191). The multimodal group had significantly lower immediate postoperative pain at rest (P < 0.001) and during movement (P < 0.001), as well as longer time to first opioid use (P = 0.047) and higher QoR-15K scores (P = 0.004). No significant differences were observed in the other parameters. Conclusions: Multimodal analgesia with intermediate CPB did not reduce 24 h opioid consumption after CEA. However, it was associated with better early postoperative pain control and recovery scores.

We sought to evaluate the efficacy of intravenous dexamethasone in reducing rebound pain post-orthopedic wrist and hand surgery, administered prior to supraclavicular brachial plexus blockade. We conducted a randomized placebo-controlled trial on 56 patients scheduled for elective wrist and hand surgery under supraclavicular brachial plexus blockade. We randomized participants into either a control group, receiving 0.9 KCT0007208 ); first submitted 5 April 2022.

INTRODUCTION:Intrathecal morphine (ITM) provides effective analgesia for pure laparoscopic donor hepatectomy (PLDH); however, its analgesic effect may be insufficient during the immediate postoperative period. We evaluated whether adding bilateral transversus abdominis plane block (TAPB) to ITM enhances analgesia and recovery in living liver donors undergoing PLDH. METHODS:This randomized controlled trial was conducted at a single center in Korea between 9 May 2023 and 9 October 2024. 80 living liver donors scheduled for PLDH were prospectively randomized into two groups: a control group receiving ITM alone and a TAPB group receiving bilateral TAPB plus ITM. The primary outcome was the worst pain score recorded at rest in the postanesthesia care unit (PACU). RESULTS:The worst pain score at rest during the PACU stay was significantly lower in the TAPB group than in the control group (median difference: 3; 95% CI 2 to 4; p<0.001). Lower pain scores persisted in the TAPB group for up to 4 hour postoperatively and were accompanied by significantly decreased cumulative opioid consumption at 1, 4 and 24 hours postoperatively (p=0.029, p=0.023, and p=0.018, respectively). At 24 hours postoperatively, the TAPB group reported a higher Quality of Recovery-15K score than the control group (p=0.030). Incidence of opioid-related complications was comparable between groups. CONCLUSIONS:Bilateral TAPB combined with ITM significantly enhanced analgesia and reduced opioid requirements during the immediate postoperative period after PLDH in living liver donors. Additionally, TAPB improved the Quality of Recovery at 24 hours postoperatively. TRIAL REGISTRATION:Clinical research information service identifier: KCT0008406.

INTRODUCTION:This study compared the analgesic effect of single-shot erector spinae plane block (ESPB) or posterior quadratus lumborum block (QLB) versus systemic analgesia alone after laparoscopic major liver resection. METHODS:This randomized controlled trial was conducted at a single referral center between August 2022 and January 2024. 114 patients undergoing laparoscopic major liver resection were randomized to one of three groups: control, ESPB, or QLB (1:1:1). The control group received systemic analgesia without regional anesthesia, whereas both ESPB and QLB groups received an additional regional anesthesia using 40 mL of 0.5 % ropivacaine. The primary outcome was cumulative opioid consumption within 24 h post-surgery. Secondary outcomes included cumulative opioid consumption, pain intensity, and recovery parameters during 72 h post-surgery. RESULTS:Cumulative opioid consumption (median [IQR]) within 24 h post-surgery was not significantly different among the groups (control, 35 mg [25, 53]; ESPB, 32 mg [21, 44]; QLB, 29 mg [22, 40]; adjP > 0.99). Cumulative opioid consumption at 1 and 48 h also did not significantly differ among the three groups (adjP = 0.336 and 0.732) but was significantly lower at 72 h post-surgery (adjP = 0.032). Pain at rest during the postanesthesia care unit (PACU) stay and at 48 h post-surgery was lower in ESPB and QLB versus control, while pain when coughing in both block groups was reduced only during the PACU stay. CONCLUSIONS:Neither ESPB nor posterior QLB resulted in a significant decrease in cumulative opioid consumption within 24 h after laparoscopic major liver resection.

STUDY OBJECTIVE:To determine if single-injection bilateral posterior quadratus lumborum block (QLB) with ropivacaine would improve postoperative analgesia in the first 24 h after laparoscopic hepatectomy, compared with 0.9% saline. DESIGN:Prospective, double blinded, randomized controlled trial. SETTING:A single tertiary care center from November 2021 and January 2023. PATIENTS:A total of 94 patients scheduled to undergo laparoscopic hepatectomy due to hepatocellular carcinoma. INTERVENTIONS:Ninety-four patients were randomized into a QLB group (receiving 20 mL of 0.375% ropivacaine on each side, 150 mg in total) or a control group (receiving 20 mL of 0.9% saline on each side). MEASUREMENTS:The primary outcome was the cumulative opioid consumption during the initial 24-h post-surgery. Secondary outcomes included pain scores and intraoperative and recovery parameters. MAIN RESULTS:The mean cumulative opioid consumption during the initial 24-h post-surgery was 30.8 ± 22.4 mg in the QLB group (n = 46) and 34.0 ± 19.4 mg in the control group (n = 46, mean differences: -3.3 mg, 95% confidence interval, -11.9 to 5.4, p = 0.457). The mean resting pain score at 1 h post-surgery was significantly lower in the QLB group than in the control group (5 [4-6.25] vs. 7 [4.75-8], p = 0.035). No significant intergroup differences were observed in the resting or coughing pain scores at other time points or in other secondary outcomes. CONCLUSIONS:Preoperative bilateral posterior QLB did not reduce cumulative opioid consumption during the first 24 h after laparoscopic hepatectomy.

IntroductionThe large-scale artificial intelligence (AI) language model chatbot, Chat Generative Pre-Trained Transformer (ChatGPT), is renowned for its ability to provide data quickly and efficiently. This study aimed to assess the medical responses of ChatGPT regarding anesthetic procedures.MethodsTwo anesthesiologist authors selected 30 questions representing inquiries patients might have about surgery and anesthesia. These questions were inputted into two versions of ChatGPT in English. A total of 31 anesthesiologists then evaluated each response for quality, quantity, and overall assessment, using 5-point Likert scales. Descriptive statistics summarized the scores, and a paired sample t-test compared ChatGPT 3.5 and 4.0.ResultsRegarding quality, “appropriate” was the most common rating for both ChatGPT 3.5 and 4.0 (40 and 48%, respectively). For quantity, responses were deemed “insufficient” in 59% of cases for 3.5, and “adequate” in 69% for 4.0. In overall assessment, 3 points were most common for 3.5 (36%), while 4 points were predominant for 4.0 (42%). Mean quality scores were 3.40 and 3.73, and mean quantity scores were − 0.31 (between insufficient and adequate) and 0.03 (between adequate and excessive), respectively. The mean overall score was 3.21 for 3.5 and 3.67 for 4.0. Responses from 4.0 showed statistically significant improvement in three areas.ConclusionChatGPT generated responses mostly ranging from appropriate to slightly insufficient, providing an overall average amount of information. Version 4.0 outperformed 3.5, and further research is warranted to investigate the potential utility of AI chatbots in assisting patients with medical information.

Objective To investigate the hepatic effects of high-dose intravenous (IV) iron, including those on liver function and the degree of fibrosis, in a rat model of cirrhosis. Methods We evenly allocated 25 Sprague–Dawley rats into five groups: normal rats (control group), cirrhotic rats receiving IV normal saline (liver cirrhosis [LC] group), and cirrhotic rats receiving 20, 40, or 80 mg/kg IV ferric carboxymaltose (LC-iron20, LC-iron40, and LC-iron80 group, respectively). Biochemical parameters were compared at 0, 7, 14, 21, and 28 days. The degrees of hepatic fibrosis and iron deposition were evaluated. Inflammatory and oxidative stress markers were also compared. Results There were no significant differences in the 28-day serum alanine aminotransferase levels among the LC-iron20, LC-iron40, and LC-iron80 groups (69 ± 7, 1003 ± 127, 1064 ± 309, 919 ± 346, and 820 ± 195 IU/L in the control, LC, LC-iron20, LC-iron40, and LC-iron80 groups, respectively). Hepatic iron accumulation increased in a dose-dependent manner, but the degree of hepatic fibrosis was comparable among the groups. The inflammatory and oxidative stress marker levels did not differ significantly according to the IV iron dose. Conclusions Administration of IV iron at various high doses appears safe in our rat model of cirrhosis.

BACKGROUND:This study aimed to compare the analgesic effects of programmed intermittent epidural boluses (PIEB) and continuous epidural infusion (CEI) for postoperative analgesia after elective cesarean section (CS).METHODS:Seventy-four women who underwent elective CS were randomized to receive either PIEB or CEI. The PIEB group received 4 ml-intermittent boluses of 0.11% ropivacaine every hour at a rate of 120 ml/h. The CEI group received a constant rate of 4 ml/h of 0.11% ropivacaine. The primary outcome was the pain score at rest at 36 h after CS. Secondary outcomes included the pain scores during mobilization, time-weighted pain scores, the incidence of motor blockade, and complications-related epidural analgesia during 36 h after CS.RESULTS:The pain score at rest at 36 h after CS was significantly lower in the PIEB group compared with that in the CEI group (3.0 vs. 0.0; median difference: 2, 95% CI [1, 2], P < 0.001). The mean time-weighted pain scores at rest and during mobilizations were also significantly lower in the PIEB group than in the CEI group (pain at rest; mean difference [MD]: 37.5, 95% CI [24.6, 50.4], P < 0.001/pain during mobilization; MD: 56.6, 95% CI [39.8, 73.5], P < 0.001). The incidence of motor blockade was significantly reduced in the PIEB group compared with that in the CEI group (P < 0.001).CONCLUSIONS:PIEB provides superior analgesia with less motor blockade than CEI in postpartum women after CS, without any apparent adverse events.

Study objective: To investigate the analgesic efficacy of erector spinae plane block (ESPB) in major gynecologic surgery, expressed as cumulative opioid consumption 24 h after surgery. Design: A single-center, patient-assessor blinded, randomized controlled study. Setting: Samsung medical center (tertiary university hospital), between February 2022 to January 2023. Patients: Eighty-eight females undergoing major surgery with long midline incision for gynecologic malignancy. Interventions: Patients were randomly assigned to receive standard systemic analgesia (Control group) or ESPB (ESPB group). ESPB was performed bilaterally at the level of the 9th thoracic vertebra with a mixture of 20 mL of 0.5% ropivacaine and 100 mu g of epinephrine. Measurements: The primary outcome was cumulative opioid consumption at 24 h postoperatively. Secondary outcomes included opioid consumption and pain severity during the 72 h after surgery. The variables regarding postoperative recovery and patient-centered outcomes were compared. Main results: The mean cumulative opioid consumption 24 h after surgery was 35.8 mg in the ESPB group, which was not significantly different from 41.4 mg in the control group (mean difference, 5.5 mg; 95% CI -1.7 to 12.8 mg; P = 0.128). However, patient satisfaction regarding analgesia was significantly higher in the ESPB group compared with the control group at 24 h postoperative (median difference, -1; 95% CI -3 to 0; P = 0.038). There were no significant differences in the variables associated with postoperative recovery. Conclusion: ESPB did not reduce opioid consumption during the 24 h postoperative but attenuated pain intensity during the early period after surgery.

Interscalene brachial plexus block (ISBPB) provides optimal analgesia for shoulder surgery. However, several limitations still exist, including the short duration of analgesia, rebound pain, a high incidence of unilateral diaphragmatic paresis, and potential risk of nerve damage, prompting the search for alternative techniques. Many alternatives to ISBPB have been studied to alleviate these concerns, and clinicians should choose an appropriate option based on the patient's condition. In this mini-review, we aimed to present recent updates on ISBPB while discussing our clinical experiences in shoulder surgery.

Background and Aims Posterior quadratus lumborum block is accepted analgesic strategy in abdominal surgery. We examined whether bilateral, single-injection posterior quadratus lumborum block with ropivacaine could improve on postoperative analgesia compared to 0.9% saline in patients undergoing laparoscopic hepatectomy. Methods Ninety-four patients were randomized to receive bilateral posterior quadratus lumborum block (20 mL of 0.375% ropivacaine on each side, 150 mg total) or control group (20 mL of 0.9% saline on each side). Primary outcome was cumulative opioid consumption during the first 24 h after surgery. Secondary outcomes included pain scores, intraoperative parameters and recovery parameters. Results Mean cumulative opioid consumption during the first 24 h after surgery was 31.2 ± 22.4 mg in quadratus lumborum block group (n=46) and 34.5 ± 19.4 mg in control group (n=46, mean difference: -3.3 mg, 95% confidence interval, -12.0 to 5.4, p=0.453). Median resting pain score at 1 h post- surgery was significantly lower in quadratus lumborum block group (5 [4, 6.25] vs. 7 [4.75, 8] , p=0.035). There were no significant differences in resting or coughing pain scores at other time points and other secondary outcomes. Conclusions Bilateral posterior quadratus lumborum block did not reduce the cumulative opioid consumption during the first 24 h after laparoscopic hepatectomy. ethics committee approval

Background Compared with open surgery, laparoscopic liver resection is a minimally invasive surgical technique. However, a number of patients experience moderate-to-severe postoperative pain after laparoscopic liver resection. This study aims to compare the postoperative analgesic effects of erector spinae plane block (ESPB) and quadratus lumborum block (QLB) in patients undergoing laparoscopic liver resection. Methods One hundred and fourteen patients undergoing laparoscopic liver resection will be randomly allocated to three groups (control, ESPB, or QLB) in a 1:1:1 ratio. In the control group, participants will receive systemic analgesia consisting of regular NSAIDs and fentanyl-based patient-controlled analgesia (PCA) according to the institutional postoperative analgesia protocol. In the two experimental groups (ESPB or QLB group), the participants will receive preoperative bilateral ESPB or bilateral QLB in addition to systemic analgesia according to the institutional protocol. ESPB will be performed at the 8th thoracic vertebra level with ultrasound guidance before surgery. QLB will be performed in the supine position on the posterior plane of the quadratus lumborum with ultrasound guidance before surgery. The primary outcome is cumulative opioid consumption 24 h after surgery. Secondary outcomes are cumulative opioid consumption, pain severity, opioid-related adverse events, and block-related adverse events at predetermined time points (24, 48, and 72 h after surgery). Differences in plasma ropivacaine concentrations in the ESPB and QLB groups would be investigated, and the quality of postoperative recovery among the groups will be compared. Discussion This study will reveal the usefulness of ESPB and QLB in terms of postoperative analgesic efficacy and safety in patients undergoing laparoscopic liver resection. Additionally, the study results will provide information on the analgesic superiority of ESPB versus QLB in the same population. Trial registration Prospectively registered with the Clinical Research Information Service on August 3, 2022; KCT0007599.

The scalp nerve block, created by injecting local anesthetics around the scalp nerves, is reported to effectively reduce pain after surgery. In this study, we evaluated the efficacy of scalp nerve block in patients with hemifacial spasm (HFS) undergoing microvascular decompression (MVD). Seventy-four patients who underwent MVD for HFS were enrolled. The block group received scalp nerve block with 0.5% ropivacaine before surgery. The primary outcome was cumulative dose of rescue analgesics 24 h postoperatively. The secondary outcomes were included pain scores, postoperative antiemetic consumption, and Quality of Recovery-15 scale. The cumulative dose of rescue analgesics at 24 h postoperatively was not significantly different between the two groups (4.80 ± 3.64 mg vs. 5.92 ± 3.95 mg, p = 0.633). However, the pain score was significantly reduced in the block group at 6, 12, and 24 h postoperatively. Postoperative antiemetic consumption was lower in the block group than the control group at 12 h. There were no significant differences between the two groups for other secondary outcomes. In MVD for HFS, a preoperative scalp nerve block might reduce postoperative pain in the early postoperative period, but a larger study using a multimodal approach is needed to confirm the efficacy of a scalp block.

BACKGROUND:Children receiving proton therapy require repeated sedation. In this study, we aimed to investigate the utility of the perfusion index (PI) for evaluating consciousness level during repeated propofol sedation. METHODS:In this prospective observational study, children aged from birth to 19 years old scheduled for proton therapy under repeated propofol sedation were enrolled. The primary outcome was the equivalence of PI values 5 min after anesthesia induction on consecutive sedation. Total consumption of propofol during sedation, time to reach the University of Michigan sedation scale (UMSS) score 1 after end of proton therapy, and duration of post-anesthesia care unit (PACU) stay were recorded. RESULTS:The PI values measured 5 min after induction of anesthesia were not equivalent to each other in consecutive sedation except for the second versus third (1st vs. 2nd: 97.5% CI: -1.34, 0.91; p = 0.206, 0.034; 2nd vs. 3rd: 97.5% CI: -0.87, 0.94; p = 0.023, 0.036 3rd vs. 4th: 97.5% CI: -2.08, -0.26; p < 0.99, <0.001; 4th vs. 5th: 97.5% CI: 0.21, 2.28; p < 0.001, >0.99; respectively). In consecutive sedation, there was not a significantly different difference in the time to reach UMSS score 1 (p > 0.99, all) for total consumption of propofol, time to reach UMSS score 1 after the end of proton therapy, and duration of PACU stay. CONCLUSIONS:During repeated propofol sedation in children, PI was insufficient to be used as an indicator of consciousness level assessment. However, we suggest that the information related to repeated sedation provided by this study may be helpful in clinical practice.

BACKGROUND Preoperative anxiety is a common problem in pregnant women undergoing elective cesarean section. We aimed to determine the anxiolytic effects of chewing gum in pregnant women undergoing elective cesarean section under regional anesthesia. METHODS This was a single-center, prospective, randomized controlled trial. Sixty-six women were randomly assigned to either the control group (n=33) or gum group (n=33) in a 1:1 ratio. In the gum group, the participants chewed xylitol gum for at least 10 min/h, regardless of fasting. Gum chewing was started at 5 pm a day before surgery and continued till the participant entered the operation room. In the control group, participants were requested to follow fasting guidelines without further instruction. The primary outcome was preoperative anxiety measured using the Amsterdam Preoperative Anxiety and Information Scale (APAIS) immediately before surgery. RESULTS The APAIS score immediately before surgery showed no significant difference between the control and the gum group (19.2±5.8 vs. 19.1±4.1, P>0.99). There were no statistically significant differences in the eight items related to anxiety: unfitness, concentration difficulty, hunger, thirst, dry mouth, fatigue, headache, and nausea. However, the pain score during the procedure of combined spinal epidural anesthesia was significantly lower in the chewing gum group [4 (IQR, 3-5.5)] than in the control group [5 (IQR, 3-7), P=0.045]. CONCLUSIONS Preoperative gum chewing did not reduce anxiety levels measured immediately before entering the operating room in the participants undergoing elective cesarean section. TRIAL REGISTRATION Clinical Trial Registry of Korea; https://cris.nih.go.kr/cris/index.jsp and identifier: KCT0006602; date of registration: September 27, 2021; principal investigator's name: RyungA Kang).

BACKGROUND:Intrathecal morphine (ITM) injection is an effective postoperative analgesic strategy in open or laparoscopic donor hepatectomy; however, the optimal dose has not been determined. In this trial, we compared the post-operative analgesic effects of two doses (300 vs. 400 μg) of ITM injections. METHODS:In this prospective randomized non-inferiority trial, 56 donors were divided into either the 300 μg or 400 μg ITM group (n = 28, each). The primary outcome was the resting pain score at 24 h postoperatively. Pain scores, cumulative opioid consumption, and side effects (postoperative nausea and vomiting [PONV]) were compared up to 48 h postoperatively. RESULTS:Fifty-five donors participated in the entire study. The mean resting pain scores at 24 h after surgery were 1.7 ± 1.6 and 1.7 ± 1.1 in the ITM 300 and ITM 400 groups, respectively (mean difference, 0 [95% CI, -.8 to .7], p = .978). The upper limit of the 95% CI was lower than the prespecified non-inferiority margin (δ = 1), indicating that non-inferiority had been established. The incidence of PONV was lower in the ITM 300 group than in the ITM 400 group at 18 (p = .035) and 24 h postoperatively (p = .015). There were no significant differences in the resting and coughing pain scores and cumulative opioid consumption at any time point. CONCLUSION:For laparoscopic donor hepatectomy, preoperative ITM 300 μg exhibited non-inferior postoperative analgesic effects compared to ITM 400 μg, with a lower incidence of PONV.