Relationship between preinduction electroencephalogram patterns and propofol sensitivity in adult patients.

PURPOSE: To determine the precise induction dose, an objective assessment of individual propofol sensitivity is necessary. This study aimed to investigate whether preinduction electroencephalogram (EEG) data are useful in determining the optimal propofol dose for the induction of general anesthesia in healthy adult patients. METHODS: Seventy healthy adult patients underwent total intravenous anesthesia (TIVA), and the effect-site target concentration of propofol was observed to measure each individual's propofol requirements for loss of responsiveness. We analyzed preinduction EEG data to assess its relationship with propofol requirements and conducted multiple regression analyses considering various patient-related factors. RESULTS: Patients with higher relative delta power (ρ = 0.47, p < 0.01) and higher absolute delta power (ρ = 0.34, p = 0.01) required a greater amount of propofol for anesthesia induction. In contrast, patients with higher relative beta power (ρ = -0.33, p < 0.01) required less propofol to achieve unresponsiveness. Multiple regression analysis revealed an independent association between relative delta power and propofol requirements. CONCLUSION: Preinduction EEG, particularly relative delta power, is associated with propofol requirements during the induction of general anesthesia. The utilization of preinduction EEG data may improve the precision of induction dose selection for individuals.

The Effect of Postoperative Single-Injection Adductor Canal Block in Total Knee Arthroplasty Under Spinal Anesthesia With Intraoperative Dexmedetomidine Infusion.

Background: Single-injection adductor canal block (SACB) is one of the multimodal pain managements in total knee arthroplasty. The effect of an intrathecal local anesthetic is prolonged with an intraoperative dexmedetomidine infusion. Currently, SACB's effect along with the prolonged spinal anesthesia effect by dexmedetomidine has not been studied elsewhere. Methods: Seventy-eight patients were randomized to either the SACB group (n = 39) or the control group (n = 39). Spinal anesthesia and continuous infusion of dexmedetomidine were performed intraoperatively. The SACB was performed using 15 mL of either 0.5% ropivacaine or normal saline in postanesthesia care unit postoperatively. Primary endpoint examined the average numerical rating scale (NRS) pain scores at 2, 6, 12, and 24 hours after SACB while resting or moving. The secondary outcomes were the morphine equivalent, postoperative nausea and vomiting score, quadriceps strength, and overall satisfaction score. Results: The SACB group showed a lower average NRS pain score until 24 hours than the control group (2.4 vs 3.3 resting, 3.4 vs 4.1 moving). Resting and moving NRS scores at 6 and 12 hours were significantly lower in the SACB group, whereas no difference was found at 2, 24, and 48 hours, regardless of movement. The satisfaction score was higher in the SACB group than in the control group (9 [7.3-10.0] vs 7 [5.3-8.8]), and morphine equivalent at 2 hours was lower in the SACB group (2 [1-3]) than in the control group (2.9 [1.6-4]). Conclusions: SACB provided an additional analgesic effect in patients undergoing total knee arthroplasty under spinal anesthesia with continuous dexmedetomidine intravenous infusion.

Visceral Adipose Tissue Reduction Measured by Deep Neural Network Architecture Improved Reflux Esophagitis Endoscopic Grade.

INTRODUCTION: Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography (CT) and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. METHODS: Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal CT at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression. RESULTS: We enrolled 6,570 patients who underwent EGD and abdominal CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (hazard ratio: 3.22, 95% confidence interval: 1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated. DISCUSSION: Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.

Preoperative frailty assessment with ultrasound in elderly patients scheduled for total knee arthroplasty.

BACKGROUND: Frailty, a decline in physical and cognitive reserve capacity, renders patients susceptible to various stressors and has been linked to adverse outcomes and increased healthcare utilization. This study aimed to determine whether ultrasound measurements of the rectus abdominis (RA) and biceps brachii (BB) could predict frailty in patients scheduled for total knee arthroplasty. METHODS: Frailty was assessed using the Clinical Frailty Scale in adults aged ≥60 years. Ultrasound measurements of the rectus abdominis, BB, and quadriceps femoris muscles, along with thigh circumference measurements, were obtained before surgery. The predictive ability of the unadjusted and BMI- and body surface area (BSA)-adjusted measurements were evaluated using receiver operating characteristic curve analysis and area under the curve (AUC) values. Postoperative outcomes, such as admission to the intensive care unit or skilled nursing facility, delirium, falls, re-hospitalization, and 30-day mortality were recorded. RESULTS: We analyzed data from 148 patients. BB thickness provided a fair prediction of frailty. Average measurements of both BB adjusted for BMI (0.708, 95% CI 0.602-0.814; P<0.001), and BSA (0.708, 95% CI 0.598-0.817; P<0.001) had the highest AUC values. RA muscle measurements could not discriminate frailty. The BMI-adjusted measurements for: right quadriceps femoris thickness (AUC 0.614, 95% CI 0.503-0.725; P=0.044), left thigh circumference (AUC 0.648, 95% CI 0.528-0.769; P=0.016), and average thigh circumference (AUC 0.630, 95% CI 0.511-0.750; P=0.033) had statistically significant but poor AUC values. CONCLUSIONS: Preoperative ultrasound measurements of the bilateral BB can fairly predict frailty in patients scheduled for total knee arthroplasty.

Comparison of remimazolam and dexmedetomidine for intraoperative sedation in patients undergoing lower extremity surgery under spinal anesthesia: a randomized clinical trial.

BACKGROUND: Dexmedetomidine sedation has advantages, such as low incidence of respiratory depression and prolonged block duration, but also significant disadvantages, such as slow onset, high rate of sedation failure, and a long context-sensitive half-life. Remimazolam provides rapid sedation and recovery, high sedation efficacy and has minimal hemodynamic effects. We hypothesized that patients who received remimazolam would require less rescue midazolam than dexmedetomidine. METHODS: Patients (n=103) scheduled for surgery under spinal anesthesia were randomized to receive dexmedetomidine (DEX group) or remimazolam (RMZ group) targeting a Modified Observer's Assessment of Alertness/Sedation score of 3 or 4. Rescue midazolam was administered if the patient failed to be sedated after the initial loading dose or despite infusion rate adjustment. RESULTS: Rescue midazolam administration was significantly higher in the DEX group (0% vs 39.2%; p<0.001). Patients in the RMZ group reached the target sedation level more rapidly. The incidences of bradycardia (0% vs 25.5%; p<0.001) and hypertension (0% vs 21.6%; p<0.001) were higher in the DEX group. Respiratory depression occurred at a higher rate in the RMZ group (21.2% vs 2.0%; p=0.002), but no patients required manual ventilation. Patients in the RMZ group recovered faster, had a shorter PACU stay and higher satisfaction scores. Hypotensive episodes in the PACU were more frequent in the DEX group (1.9% vs 29.4%; p<0.001). CONCLUSIONS: Remimazolam showed excellent sedation efficacy, minimal hemodynamic effects, and fewer adverse events in the PACU than dexmedetomidine. However, it is important to note that respiratory depression was more frequent with the use of remimazolam. TRIAL REGISTRATION NUMBER: NCT05447507.

Noninvasive hemoglobin monitoring for maintaining hemoglobin concentration within the target range during major noncardiac surgery: A randomized controlled trial.

STUDY OBJECTIVE: The effect of noninvasive CO-oximetry hemoglobin (SpHb) monitoring on the clinical outcomes of patients undergoing surgery remains unclear. This trial aimed to evaluate whether SpHb monitoring helps maintain hemoglobin levels within a predefined target range during major noncardiac surgeries with a potential risk of intraoperative hemorrhage. DESIGN: A single-center, prospective, randomized controlled trial. SETTING: University hospital. PATIENTS: One hundred and thirty patients undergoing elective noncardiac surgery with a potential risk of hemorrhage. INTERVENTIONS: Patients were randomly allocated to undergo either SpHb-guided management (SpHb group) or usual care (control group). MEASUREMENTS: The primary outcome was the rate of deviation of the total hemoglobin concentration (determined from laboratory testing) from a pre-specified target range (8-14 g/dL). This was defined as the number of laboratory tests revealing such deviations divided by the total number of laboratory tests performed during the surgery. MAIN RESULTS: The primary outcome occurred significantly less frequently in the SpHb group as compared to that in the control group (15/555 [2.7%]) vs. 68/598 [11.4%]; relative risk, 0.24; 95% confidence interval, 0.13-0.41; P < 0.001). Fewer point-of-care blood tests were performed in the SpHb group than in the control group (median [interquartile range], 2 [1-4] vs. 4 [2-5]; P < 0.001). There were no significant intergroup differences in the number of patients who received red blood cell transfusions during surgery (SpHb vs. control, 33.8% vs. 46.2%; P = 0.201). The incidence of unnecessary red blood cell preparation (>2 units) was lower in the SpHb group than in the control group (3.1% vs. 16.9%; P = 0.024). CONCLUSIONS: Compared with routine care, SpHb-guided management resulted in significantly lower rates of hemoglobin deviation outside the target range intraoperatively in patients undergoing major noncardiac surgeries with a potential risk of hemorrhage. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (identifier: NCT03816514).

Positive end-expiratory pressure during one-lung ventilation for preventing atelectasis after video-assisted thoracoscopic surgery: a triple-arm, randomized controlled trial.

BACKGROUND: There is little evidence regarding the benefits of lung-protective ventilation in patients undergoing one-lung ventilation for thoracic surgery. This study aimed to determine the optimal level of positive end-expiratory pressure (PEEP) during one-lung ventilation for minimizing postoperative atelectasis through lung ultrasonography. METHODS: A total of 142 adult patients scheduled for video-assisted thoracoscopic surgery at Seoul National University Hospital between May 2019 and February 2020 were enrolled in this study. Patients were randomly assigned to different groups: 1) PEEP 3 cmH2O group; 2) PEEP 6 cmH2O group; and 3) PEEP 9 cmH2O group during one-lung ventilation. The lung ultrasound score was used to evaluate lung aeration using ultrasonography 1 hour after surgery. RESULTS: The 1-hour post-surgery lung ultrasound scores were 8.1±2.5, 6.8±2.6, and 5.9±2.6 in the PEEP 3, 6, and 9 cmH2O groups, respectively (P<0.001). The PEEP 3 cmH2O group showed significantly higher lung ultrasound scores than the PEEP 6 (adjusted P=0.034) and 9 cmH2O groups (adjusted P<0.001). The PaO2/FiO2 ratio measured at 10 minutes after the end of one-lung ventilation was significantly lower in the PEEP 3 cmH2O group (392 [331 to 469]) than the PEEP 6 cmH2O (458 [384 to 530], adjusted P=0.018) or PEEP 9 cmH2O groups (454 [374 to 522], adjusted P=0.016). CONCLUSIONS: Although the optimal level of PEEP during one-lung ventilation was not determined, the application of higher PEEP can prevent aeration loss in the ventilated lung after video-assisted thoracoscopic surgery under one-lung ventilation.

Handheld ultrasound-assisted versus palpation-guided combined spinal-epidural for labor analgesia: a randomized controlled trial.

Preprocedural ultrasound assistance can enhance the efficacy of neuraxial anesthesia in obstetrics. We investigated whether the use of handheld ultrasound can shorten the procedural time of labor combined spinal-epidural (CSE) analgesia compared with conventional landmark-guided methods. Eighty-four women requesting labor analgesia were randomly assigned to either handheld ultrasound-assisted or palpation-guided CSE analgesia. Primary outcome was procedure time of the CSE analgesia. Secondary outcomes included identification time, performance time, number of needle manipulations required for epidural/spinal success, first-attempt success rate, periprocedural pain scores, the incidence of accidental dural puncture, and patient satisfaction. Total procedure time did not significantly differ between the ultrasound and palpation groups (median [IQR], 191.5 [167-224] vs. 204.5 [163-358] s; P = 0.442). However, the performance time was significantly shorter in the ultrasound group (134.5 [115-177] vs. 183 [129-296] s; P = 0.011), although identification time was longer in the ultrasound group (53 [41-72] vs. 30.5 [21-45] s; P < 0.001). The epidural success rate at first insertion attempt was higher in the ultrasound group (85.7% vs. 59.5%, P = 0.014). Preprocedural handheld ultrasound assistance resulted in equivalent total procedure times but reduced performance times and higher first-attempt success rates. Therefore, clinicians may consider this technique for labor CSE analgesia.Trial registration: NCT04759547.

Comparison between low-volume local anesthetic with intravenous dexamethasone and conventional volume without dexamethasone for superior trunk block after arthroscopic shoulder surgery: a randomized controlled non-inferiority trial.

INTRODUCTION: This study aimed to investigate whether low-volume local anesthetic with intravenous dexamethasone can reduce the incidence of diaphragmatic paresis while maintaining the analgesic duration compared with conventional volume of local anesthetic without intravenous dexamethasone when performing ultrasound-guided superior trunk block in patients undergoing arthroscopic shoulder surgery. METHODS: Eighty-four adult patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly assigned to receive ultrasound-guided superior trunk block using 7 mL of 0.5% ropivacaine with 0.15 mg/kg of intravenous dexamethasone (treatment group), or 15 mL of 0.5% ropivacaine with intravenous normal saline (control group). The co-primary outcomes were (1) the duration of analgesia (time between block completion and onset of surgical pain with a Numeric Rating Scale pain score of 4 or higher), which was compared against a non-inferiority margin of 3 hours, and (2) the incidence of diaphragmatic paresis evaluated using M-mode ultrasonography in the post-anesthesia care unit. RESULTS: The mean duration of analgesia was 12.4 (6.8) and 11.2 (4.6) hours in the treatment and control groups, respectively (mean difference: -1.2 hours; 95% CI -3.8 to 1.3]; p for non-inferiority<0.001), meeting the non-inferiority criteria. The incidence of diaphragmatic paresis was 45.2% and 85.4% in the treatment and control groups, respectively (relative risk: 0.53; 97.5% CI 0.35 to 0.80; p<0.001). CONCLUSIONS: Superior trunk block using low-volume local anesthetic with intravenous dexamethasone can reduce the incidence of diaphragmatic paresis while providing non-inferior analgesic duration compared with the conventional volume of local anesthetic in patients undergoing arthroscopic shoulder surgery. TRIAL REGISTRATION NUMBER: Clinical Research Information Service of Republic of Korea Registry (KCT0005998).

Influence of laminectomy on the lumbosacral cerebrospinal fluid volume: A retrospective magnetic resonance imaging study.

The cerebrospinal fluid volume affects the block height of spinal anaesthesia. Laminectomy of the lumbar spine may result in increased lumbosacral cerebrospinal fluid volume. This study aimed to test the hypothesis that the lumbosacral cerebrospinal fluid volume of patients with a history of lumbar laminectomy would be larger than that of patients with normal lumbar spine anatomy using magnetic resonance imaging. Lumbosacral spine magnetic resonance images of 147 patients who underwent laminectomy at the L2 vertebrae or below (laminectomy group) and 115 patients without a history of spinal surgery (control group) were retrospectively reviewed. The lumbosacral cerebrospinal fluid volumes between the L1-L2 intervertebral disc level and the end of the dural sac were measured and compared between the two groups. The mean (standard deviation) lumbosacral cerebrospinal fluid volume was 22.3 (7.8) ml and 21.1 (7.4) ml in the laminectomy and control groups, respectively (mean difference 1.2 ml; 95% confidence interval -0.7 to 3.0 ml; P = 0.218). In the prespecified subgroup analysis according to the number of laminectomy levels, patients who underwent more than two levels of laminectomy exhibited slightly larger lumbosacral cerebrospinal fluid volume (n = 17, 30.5 (13.5) ml) compared with those who underwent two (n = 40, 20.7 (5.6) ml; P = 0.014) or one level of laminectomy (n = 90, 21.4 (6.2) ml; P = 0.010) and the control group (21.1 (7.4) ml; P = 0.012). In conclusion, the lumbosacral cerebrospinal fluid volume did not differ between patients who underwent lumbar laminectomy and those without a history of laminectomy. However, patients who underwent laminectomy at more than two levels had a slightly larger volume of lumbosacral cerebrospinal fluid than those who underwent less extensive laminectomy and those without a history of lumbar spine surgery. Further studies are warranted to confirm the subgroup analysis findings and elucidate the clinical implications of such differences in the lumbosacral cerebrospinal fluid volume.

Association of Volatile Versus Intravenous Anesthesia With Prognosis After Nephrectomy for Renal Cell Carcinoma.

BACKGROUND/AIM: A recent preclinical study reported that renal cell carcinoma was more susceptible to sevoflurane-mediated metastatic potentiation, compared to non-small cell lung cancer, suggesting that the effect of anesthetic agents on the metastatic potential varies according to cancer type. Based on this report, we conducted a retrospective cohort study to compare recurrence-free survival after nephrectomy, between renal cell carcinoma patients receiving volatile anesthesia and those receiving intravenous anesthesia. PATIENTS AND METHODS: We reviewed the electronic medical records of patients who underwent partial or radical nephrectomy for renal cell carcinoma at the Seoul National University Hospital. Patients were divided into two groups according to whether volatile or intravenous anesthesia was used for nephrectomy. A total of 651 patients (582 in the volatile and 69 in the intravenous group) were enrolled in the study. Recurrence-free survival after nephrectomy was compared using Cox proportional hazards regression analysis with inverse probability of treatment weighting. RESULTS: Cox regression analysis with inverse probability of treatment weighting revealed that volatile anesthesia had no impact on recurrence-free survival [hazard ratio (HR)=0.45; 95% confidence interval (CI)=0.07-2.85; p=0.398] or overall survival (HR=1.41; 95% CI=0.31-6.44; p=0.661). CONCLUSION: We found no significant association between volatile anesthesia and poor outcomes after nephrectomy for renal cell carcinoma. Volatile anesthetic-promoted metastatic potentiation of renal cell carcinoma, shown in a preclinical study, does not seem to be translated in the clinical setting.

Risk prediction models incorporating institutional case volume for mortality after hip fracture surgery in the elderly.

INTRODUCTION: While higher institutional case volume is associated with better postoperative outcomes in various types of surgery, institutional case volume has been rarely included in risk prediction models for surgical patients. This study aimed to develop and validate the predictive models incorporating institutional case volume for predicting in-hospital mortality and 1-year mortality after hip fracture surgery in the elderly. MATERIALS AND METHODS: Data for all patients (≥ 60 years) who underwent surgery for femur neck fracture, pertrochanteric fracture, or subtrochanteric fracture between January 2008 and December 2016 were extracted from the Korean National Health Insurance Service database. Patients were randomly assigned into the derivation cohort or the validation cohort in a 1:1 ratio. Risk prediction models for in-hospital mortality and 1-year mortality were developed in the derivation cohort using the logistic regression model. Covariates included age, sex, type of fracture, type of anaesthesia, transfusion, and comorbidities such as hypertension, diabetes, coronary artery disease, chronic kidney disease, cerebrovascular disease, and dementia. Two separate models, one with and the other without institutional case volume as a covariate, were constructed, evaluated, and compared using the likelihood ratio test. Based on the models, scoring systems for predicting in-hospital mortality and 1-year mortality were developed. RESULTS: Analysis of 196,842 patients showed 3.6% in-hospital mortality (7084/196,842) and 15.42% 1-year mortality (30,345/196,842). The model for predicting in-hospital mortality incorporating the institutional case volume demonstrated better discrimination (c-statistics 0.692) compared to the model without the institutional case volume (c-statistics 0.688; likelihood ratio test p value < 0.001). The performance of the model for predicting 1-year mortality was also better when incorporating institutional case volume (c-statistics 0.675 vs. 0.674; likelihood ratio test p value < 0.001). CONCLUSIONS: The new institutional case volume incorporated scoring system may help to predict in-hospital mortality and 1-year mortality after hip fracture surgery in the elderly population.

Retrospective analysis of the incidence and predictors of postoperative nausea and vomiting after orthopedic surgery under spinal anesthesia.

BACKGROUND: Postoperative nausea and vomiting (PONV) commonly occurs after spinal anesthesia; however, its incidence rate and predictors have been scarcely studied. Therefore, we aimed to investigate its incidence rate and potential predictors. METHODS: The electronic medical records of 6,610 consecutive patients undergoing orthopedic surgery under spinal anesthesia were reviewed between January 2016 and December 2020. The primary outcome was PONV incidence within 24 h after spinal anesthesia. Along with its incidence rate, we investigated its predictors using multivariable logistic regression analysis. RESULTS: Among the 5,691 patients included in the analysis, 1,298 (22.8%) experienced PONV within 24 h after spinal anesthesia. Female sex (odds ratio [OR]: 3.23, 95% CI [2.72, 3.83], P < 0.001), nonsmoker (OR: 2.12, 95% CI [1.46, 3.07], P < 0.001), history of PONV (OR: 1.52, 95% CI [1.26, 1.82], P < 0.001), prophylactic 5-hydroxytryptamine receptor antagonist use (OR: 0.35, 95% CI [0.24, 0.50], P < 0.001), prophylactic steroid use (OR: 0.53, 95% CI [0.44, 0.62], P < 0.001), baseline heart rate ≥ 60 beats/min (OR: 1.38, 95% CI [1.10, 1.72], P = 0.005), and postoperative opioid use (OR: 2.57, 95% CI [1.80, 3.67], P < 0.001), were significant predictors of the primary outcome. CONCLUSIONS: Our study showed the common incidence of PONV after spinal anesthesia and its significant predictors. A better understanding of its predictors may provide important information for its management.

Relationships between common carotid artery blood flow and anesthesia, pneumoperitoneum, and head-down tilt position: a linear mixed-effect analysis.

This study investigated the effects of pneumoperitoneum and the head-down tilt position on common carotid artery (CCA) blood flow in surgical patients. METHODS: This prospective observational study included 20 patients who underwent gynecological surgery. CCA blood flow was measured using Doppler ultrasound at four-time points: awake in the supine position [T1], 3 min after anesthesia induction in the supine position [T2], 3 min after pneumoperitoneum in the supine position [T3], and 3 min after pneumoperitoneum in the head-down tilt position [T4]. Hemodynamic and respiratory parameters were also recorded at each time point. Linear mixed-effect analyses were performed to compare CCA blood flow across the time points and assess its relationship with hemodynamic parameters. RESULTS: Compared with T1, CCA blood flow decreased significantly at T2 (345.4 [288.0-392.9] vs. 293.1 [253.0-342.6], P = 0.048). CCA blood flow were also significantly lower at T3 and T4 compared with T1 (345.4 [288.0-392.9] vs. 283.6 [258.8-307.6] and 287.1 [242.1-321.4], P = 0.005 and 0.016, respectively). CCA blood flow at T3 and T4 did not significantly differ from that at T2. Changes in CCA blood flow were significantly associated with changes in cardiac index and stroke volume index (P = 0.011 and 0.024, respectively). CONCLUSION: CCA blood flow was significantly decreased by anesthesia induction. Inducing pneumoperitoneum, with or without the head-down tilt position, did not further decrease CCA blood flow if the cardiac index remained unchanged. The cardiac index and stroke volume index were significantly associated with CCA blood flow. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT04233177, January 18, 2020).

Effect of real-time binaural music on sedation with dexmedetomidine during spinal anesthesia: A triple-arm, assessor-blind, randomized controlled trial.

STUDY OBJECTIVE: Binaural audio induces sedation and reduces pain and anxiety in surgical patients. This study tested the hypothesis that dexmedetomidine requirement for adequate sedation during spinal anesthesia would be lower in patients listening to music with binaural sound than that in patients listening to plain or no music. DESIGN: A triple-arm, assessor-blind, randomized controlled study. SETTING: Operating room. PATIENTS: One hundred and eighty-nine patients undergoing orthopedic surgery under spinal anesthesia. INTERVENTIONS: Patients were randomly assigned to music with binaural sound, plain music, or no music groups. Dexmedetomidine was infused for sedation during surgery. The loading infusion rate was 6 µg/kg predicted body weight (PBW)/h, followed by continuous infusion at 0.6 µg/kg PBW/hr. Loading was stopped after achieving adequate sedation, defined as the Observer's Assessment of Alertness/Sedation (OAA/S) scale score of 3. Infusion rate was adjusted every 30 min per the OAA/S scale. MEASUREMENTS: Primary outcomes were the difference in the dexmedetomidine loading dose adjusted for the patient's PBW between (1) the binaural and plain music groups and (2) the binaural and control groups. Secondary outcomes were the total dose and total loading time of dexmedetomidine; Patient State Index; relative powers of the alpha, theta, and delta bands; recovery from sedation; and patient satisfaction score. MAIN RESULTS: The final analyses included 184 patients. The PBW-adjusted dexmedetomidine loading dose was significantly lower in patients listening to music with binaural sound (1.15 ± 0.30 µg/kg PBW) than that in patients without music (1.33 ± 0.33 µg/kg PBW; mean difference, 0.18 µg/kg PBW; 95% confidence interval [CI], 0.06 to 0.29; P = 0.002). However, the difference was not statistically significant when compared with the plain music group (1.26 ± 0.36 µg/kg PBW; mean difference, 0.11 µg/kg PBW; 95% CI, -0.01 to 0.23; P = 0.070). Dexmedetomidine total dose, recovery from sedation, and patient satisfaction score showed no difference among the three groups. CONCLUSIONS: Compared with no music, music with binaural sound reduced the dexmedetomidine loading dose; however, this sedative-sparing effect of binaural sound was not found when compared to plain music.

Effect of remifentanil on post-operative analgesic consumption in patients undergoing shoulder arthroplasty after interscalene brachial plexus block: a randomized controlled trial.

PURPOSE: Remifentanil is useful in balanced anesthesia; however, there is concern regarding opioid-induced hyperalgesia. The effect of remifentanil on rebound pain, characterized by hyperalgesia after peripheral nerve block has rarely been studied. This study evaluated whether intraoperative remifentanil infusion may increase postoperative analgesic requirement in patients receiving preoperative interscalene brachial plexus block (IBP). METHODS: Sixty-eight patients undergoing arthroscopic shoulder surgery under general anesthesia were randomly allocated to remifentanil (R) or control (C) group. Preoperative IBP with 0.5% ropivacaine 15 mL was performed in all patients. Intraoperative remifentanil was administered only in the R group. Postoperative pain was controlled using intravenous patient-controlled analgesia (IV-PCA) and rescue analgesics. The primary outcome was the dosage of fentanyl-nefopam IV-PCA infused over 24 h postoperatively. The secondary outcomes included the numeric rating scale (NRS) score recorded at 4-h intervals over 24 h, amount of rescue analgesics and total postoperative analgesics used over 24 h, occurrence of intraoperative hypotension, postoperative nausea and vomiting (PONV) and delirium. RESULTS: The dosage of fentanyl-nefopam IV-PCA was significantly less in C group than R group for postoperative 24 h. Fentanyl 101 [63-158] (median [interquartile range]) µg was used in the C group, while fentanyl 161 [103-285] µg was used in the R group (median difference 64 µg, 95% CI 10-121 µg, P = 0.02). Nefopam 8.1 [5.0-12.6] mg was used in the C group, while nefopam 12.9 [8.2-22.8] mg was used in the R group (median difference 5.1 mg, 95% CI 0.8-9.7 mg, P = 0.02). The total analgesic consumption: the sum of PCA consumption and administered rescue analgesic dose, converted to morphine milligram equivalents, was higher in the R group than C group (median difference 10.9 mg, 95% CI 3.0-19.0 mg, P = 0.01). The average NRS score, the incidence of PONV and delirium, were similar in both groups. The incidence of intraoperative hypotension was higher in R group than C group (47.1% vs. 20.6%, P = 0.005). CONCLUSIONS: Remifentanil administration during arthroscopic shoulder surgery in patients undergoing preoperative IBP increased postoperative analgesic consumption.

Ultrasound-assisted spinal anesthesia: A randomized comparison between midline and paramedian approaches.

STUDY OBJECTIVE: Neuraxial ultrasonography can improve the technical performance of spinal anesthesia. However, there are no data regarding the optimal approach for ultrasound-assisted spinal anesthesia. This study aimed to compare the midline and paramedian approaches for ultrasound-assisted spinal anesthesia in adult orthopedic patients. DESIGN: A single-center, prospective, randomized controlled trial. SETTING: Operating room. PATIENTS: One hundred and twelve patients undergoing orthopedic surgery were included. INTERVENTIONS: Patients were randomized to undergo either the midline or paramedian approach for preprocedural ultrasound-assisted spinal anesthesia. MEASUREMENTS: The primary outcome was the number of needle passes required for successful dural puncture. Secondary outcomes were the number of needle insertions, first pass/attempt success rate, procedural time, and the incidence of periprocedural complications. MAIN RESULTS: The median number of needle passes was significantly lower in the paramedian group (1 [IQR, 1-2]) than in the midline group (3 [2-6]; P < 0.001). The paramedian approach showed higher first pass/attempt success rates compared with the midline group (58.9% vs. 21.4%; 91.1% vs. 53.6%; both, P < 0.001). Total procedure times were significantly shorter in the paramedian group than in the midline group (113 [72.5-146.5] vs. 196 [138-298.5] seconds; P < 0.001). The quality of sonographic images was graded as good in 94.6% of paramedian sagittal oblique views and 54.5% of transverse median views. No significant intergroup differences were found in the incidence of periprocedural complications. CONCLUSIONS: Compared with the midline approach, the ultrasound-assisted paramedian approach showed improved efficacy in terms of the number of needle manipulations, first pass success rates, and procedural time. These results suggest that the paramedian approach may be more efficient for preprocedural ultrasound-assisted spinal anesthesia. TRIAL REGISTRATION NUMBER: NCT03491943.

Anatomical changes of the ligamentum flavum and the epidural space after spinal surgery: a retrospective magnetic resonance imaging study.

BACKGROUND: Anatomical changes of the ligamentum flavum (LF) and epidural space (ES) after spinal surgery may affect the loss-of-resistance during interlaminar epidural procedure and distribution of drug administered into the ES. This study aims to investigate clinically relevant anatomical changes of the LF and ES after spinal surgery. METHODS: We reviewed pre- and postoperative lumbar magnetic resonance imaging data from 34 patients who underwent spinal surgeries at two vertebral body levels. The presence and thickness of LF (midline, right, and left) and the cross-sectional area of the ES were checked at L2, L3, L4, L5, and S1 levels. RESULTS: Intact LF was observed in only 4/34 (12%) and 9/27 (33%) patients at the upper and lower vertebral level of surgery, respectively. Intact LF was observed in 30/30 (100%), 28/33 (75%), and 2/4 (50%) patients, at two levels above, one level above, and one level below the segment level of surgery, respectively. Intact ES was observed in only 4/34 (12%) and 8/27(30%) patients at the upper and lower vertebral level of surgery, respectively. Intact ES was observed in 30/30 (100%), 29/33 (88%), and 3/4 (75%) patients, at two levels above, one level above, and one level below the segment level of surgery, respectively. The thickness of LF and the cross-sectional area of ES significantly decreased at the levels of spinal surgery. CONCLUSIONS: For epidural anesthesia in patients who have previously undergone spinal surgery, it is reasonable to select a needle insertion site other than the level of spinal surgery.

Inverse correlation between gastroesophageal reflux disease and atrophic gastritis assessed by endoscopy and serology.

BACKGROUND: Helicobacter pylori (H. pylori) infection is known to prevent the occurrence of gastroesophageal reflux disease (GERD) by inducing gastric mucosal atrophy. However, little is known about the relationship between atrophic gastritis (AG) and GERD. AIM: To confirm the inverse correlation between AG and the occurrence and severity of GERD. METHODS: Individuals receiving health checkups who underwent upper gastrointestinal endoscopy at Seoul National University Healthcare System Gangnam Center were included. The grade of reflux esophagitis was evaluated according to the Los Angeles classification. Endoscopic AG (EAG) was categorized into six grades. Serologic AG (SAG) was defined as pepsinogen I ≤ 70 ng/mL and pepsinogen I/II ratio ≤ 3.0. The association between the extent of EAG and SAG and the occurrence and severity of GERD was evaluated using multivariate logistic regression analysis. RESULTS: In total, 4684 individuals with GERD were compared with 21901 healthy controls. In multivariate logistic regression analysis, advanced age, male sex, body mass index > 23 kg/m2, presence of metabolic syndrome, current smoking, and alcohol consumption were associated with an increased risk of GERD. Seropositivity for H. pylori immunoglobulin G antibodies was associated with a decreased risk of GERD. There was an inverse correlation between the extent of EAG and occurrence of GERD: Odds ratio (OR), 1.01 [95% confidence interval (CI): 0.90-1.14] in C1, 0.87 (0.78-0.97) in C2, 0.71 (0.62-0.80) in C3, 0.52 (0.44-0.61) in O1, 0.37 (0.29-0.48) in O2, and 0.28 (0.18-0.43) in O3. Additionally, the extent of EAG showed an inverse correlation with the severity of GERD. The presence of SAG was correlated with a reduced risk of GERD (OR = 0.49, 95%CI: 0.28-0.87, P = 0.014). CONCLUSION: The extent of EAG and SAG exhibited strong inverse relationships with the occurrence and severity of GERD. AG followed by H. pylori infection may be independently protect against GERD.