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.

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.

Correlation Between Pain Intensity and Quality of Recovery After Video-Assisted Thoracic Surgery for Lung Cancer Resection.

Purpose: The Quality of Recovery-15 (QoR-15) questionnaire provides a multifaceted assessment of postoperative recovery, and the resulting score is recommended as an endpoint in clinical studies focused on postoperative pain. We aimed to investigate the correlation between the QoR-15 score and postoperative pain intensity in surgical patients. Patients and Methods: Adult patients who underwent video-assisted thoracoscopic surgery (VATS) for lung cancer resection and were enrolled in a prospective registry or in a previous prospective study were included in this study. Baseline and perioperative data, including the results of assessment using the Korean version of the QoR-15 (QoR-15K) questionnaire at 48 hours postoperatively, were collected from the database. Correlations between the QoR-15K total score, questionnaire dimensions, and postoperative pain intensity at 48 hours postoperatively were determined using the Spearman correlation coefficient (ρ). Results: We analyzed a total of 137 eligible patients. Significant negative correlations were noted between the QoR-15K total score and pain intensity at rest (ρ = -0.45, 95% confidence interval [CI]: -0.57 - -0.31, P < 0.001) and during coughing (ρ = -0.55, 95% CI: -0.65 - -0.42, P < 0.001) at 48 hours postoperatively. The pain dimension and pain intensity at 48 hours postoperatively showed significant correlations with physical comfort, emotional state, and physical independence dimensions. Multivariable logistic regression revealed a significant negative association between the pain score at 24 hours postoperatively and good or excellent postoperative recovery. Conclusion: The results support the impact of postoperative pain on the overall postoperative quality of recovery in patients who underwent VATS for lung cancer resection. Moreover, the QoR-15K score may be considered as a primary endpoint in clinical studies on postoperative pain control.

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).

Intraoperative neurological pupil index and postoperative delirium and neurologic adverse events after cardiac surgery: an observational study.

Neurological pupil index (NPi) calculated by automated pupillometry predicts clinical outcomes in critically ill patients. However, there are few data on intraoperative NPi and postoperative outcome after cardiac surgery. We evaluated the relationships between intraoperative NPi and clinical outcomes, such as delirium, in cardiac surgery patients. NPi was measured at baseline, after anesthesia induction, at 30 min intervals after initiation of cardiopulmonary bypass or anastomosis of coronary artery bypass graft, and at skin closure. Abnormal NPi was defined as one or more measurements of NPi < 3.0 during surgery. The worst intraoperative NPi was recorded, then multivariate logistic regression analysis was performed to evaluate the relationship between abnormal NPi and postoperative delirium following cardiac surgery. Among 123 included patients, postoperative delirium developed in 19.5% (24/123) of patients. Intraoperative abnormal NPi was significantly associated with postoperative delirium (odds ratio 6.078; 95% confidence interval 1.845-20.025; P = 0.003) after adjustment for Society of Thoracic Surgeons Predicted Risk of Mortality score, coronary artery disease, and use of calcium channel blockers. In conclusion, abnormal intraoperative NPi independently predicted postoperative delirium following cardiac surgery. Intraoperative application of pupillometry may have prognostic value for development of postoperative delirium, thereby enabling close surveillance and early intervention in high-risk patients.Registry number: ClinicalTrials.gov (NCT04136210).

Effects of intraoperative inspired oxygen fraction (FiO2 0.3 vs 0.8) on patients undergoing off-pump coronary artery bypass grafting: the CARROT multicenter, cluster-randomized trial.

BACKGROUND: To maintain adequate oxygenation is of utmost importance in intraoperative care. However, clinical evidence supporting specific oxygen levels in distinct surgical settings is lacking. This study aimed to compare the effects of 30% and 80% oxygen in off-pump coronary artery bypass grafting (OPCAB). METHODS: This multicenter trial was conducted in three tertiary hospitals from August 2019 to August 2021. Patients undergoing OPCAB were cluster-randomized to receive either 30% or 80% oxygen intraoperatively, based on the month when the surgery was performed. The primary endpoint was the length of hospital stay. Intraoperative hemodynamic data were also compared. RESULTS: A total of 414 patients were cluster-randomized. Length of hospital stay was not different in the 30% oxygen group compared to the 80% oxygen group (median, 7.0 days vs 7.0 days; the sub-distribution hazard ratio, 0.98; 95% confidence interval [CI] 0.83-1.16; P = 0.808). The incidence of postoperative acute kidney injury was significantly higher in the 30% oxygen group than in the 80% oxygen group (30.7% vs 19.4%; odds ratio, 1.94; 95% CI 1.18-3.17; P = 0.036). Intraoperative time-weighted average mixed venous oxygen saturation was significantly higher in the 80% oxygen group (74% vs 64%; P < 0.001). The 80% oxygen group also had a significantly greater intraoperative time-weighted average cerebral regional oxygen saturation than the 30% oxygen group (56% vs 52%; P = 0.002). CONCLUSIONS: In patients undergoing OPCAB, intraoperative administration of 80% oxygen did not decrease the length of hospital stay, compared to 30% oxygen, but may reduce postoperative acute kidney injury. Moreover, compared to 30% oxygen, intraoperative use of 80% oxygen improved oxygen delivery in patients undergoing OPCAB. Trial registration ClinicalTrials.gov (NCT03945565; April 8, 2019).

Preliminary Study on an Alternative Test Method with MCTT HCETM for Ocular Irritation Test of Ophthalmic Medical Devices.

The sustained growth of the market for ophthalmic medical devices has increased the demand for alternatives to animal testing for the evaluation of eye irritation. The International Organization for Standardization has acknowledged the need to develop novel in vitro tests to replace animal testing. Here, we evaluated the applicability of an alternative method based on a human corneal model to test the safety of ophthalmic medical devices. 2-Hydroxyethyl methacrylate (HEMA) and Polymethyl methacrylate (PMMA), which are used to fabricate contact lenses, were used as base materials. These materials were blended with eye irritant and non-irritant chemicals specified in the OECD Test Guideline (TG) 492 and Globally Harmonized System (GHS) classification. Then, three GLP-certified laboratories performed three replicates using the developed method using 3D reconstructed human cornea epithelium, MCTT HCETM. OECD TG 492 describes the procedure used to evaluate the eye hazard potential of the test chemical based on its ability to induce cytotoxicity in a reconstructed human cornea-like epithelium (RhCE) tissue. Results: The within-laboratory reproducibility (WLR) and between-laboratory reproducibility (BLR) were both 100%. When a polar extraction solvent was used, the sensitivity, specificity, and accuracy were all 100% in each laboratory. When a non-polar extraction solvent was used, the sensitivity was 80%, the specificity was 100%, and the accuracy was 90%. The proposed method exhibited excellent reproducibility and predictive capacity within and between laboratories. Therefore, the proposed method using the MCTT HCETM model could be used to evaluate eye irritation caused by ophthalmic medical devices.

Association between intraoperative plantar regional oxygen saturation and acute kidney injury after cardiac surgery.

Acute kidney injury (AKI) is one of the most common complications after cardiac surgery, associated with increased mortality and morbidity. Near-infrared spectroscopy (NIRS) continuously measures regional oxygen saturation(rSO2) in real-time. This exploratory retrospective study aimed to investigate the association between intraoperative plantar rSO2 and postoperative AKI in cardiac surgery patients. Between August 2019 and March 2021, 394 patients were included. Plantar and cerebral rSO2 were monitored using NIRS intraoperatively. The primary outcome was AKI within 7 postoperative days. The nonlinear association between plantar rSO2, cerebral rSO2, and mean arterial blood pressure (MBP) and AKI was assessed, and plantar rSO2<45% was related to an increased risk of AKI. Multivariable logistic regression analyses revealed that longer duration and higher area under the curve below plantar rSO2<45% and MBP<65 mmHg were more likely to be associated with increased odds of AKI. In additional multivariable regression analyses, association between plantar rSO2<45% and AKI was still maintained after adjusting the duration or AUC of MBP<65 mmHg as a covariate. Cerebral rSO2 levels were not associated with AKI. Independent of MAP, intraoperative plantar rSO2 was associated with AKI after cardiac surgery. However, intraoperative cerebral rSO2 was not associated with AKI. Intraoperative plantar rSO2 monitoring may be helpful in preventing AKI.

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.

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).

Relationship between intraoperative tidal volume and acute kidney injury following off-pump coronary artery bypass grafting: A retrospective observational study.

The effect of intraoperative tidal volume (VT) on clinical outcomes after off-pump coronary artery bypass grafting (OPCAB) has not been studied. The aim of this study was to assess the relationship between intraoperative tidal volume (VT) and acute kidney injury (AKI ) after OPCAB. A total of 1049 patients who underwent OPCAB between January 2009 and December 2018 were analyzed. Patients were divided into high (>8 ml/kg) and low VT (≤8 ml/kg) groups (intraoperative median VT standardized to predicted body weight). The data were fitted using a multivariable logistic regression model. Subgroup analyses were performed according to age, sex, comorbidities, preoperative laboratory variables, operative profiles, and Cleveland score. The risk of AKI was not significantly higher in the high than the low VT group (OR: 1.15, 95% CI: 0.80-1.66; P = .459); however, subgroup analyses revealed that a high VT may increase the risk of AKI in males, patients aged < 70 years, with chronic kidney disease, a left ventricular ejection fraction < 35%, or a long duration of surgery. High intraoperative VTs were not associated with an increased risk of AKI after OPCAB. Nonetheless, it may increase the risk of AKI in certain subgroups, such as younger age, male sex, reduced renal and cardiac function, and a long surgery time.

Synthesis and Assessment of AMPS-Based Copolymers Prepared via Electron-Beam Irradiation for Ionic Conductive Hydrogels.

In this study, ionic conductive hydrogels were prepared with 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). Acrylic acid (AA), acrylamide (AAm), and 2-hydroxyethyl acrylate (HEA) were used as comonomers to complement the adhesion properties and ion conductivity of AMPS hydrogels. Hydrogels were prepared by irradiating a 20 kGy dose of E-beam to the aqueous monomer solution. With the E-beam irradiation, the polymer chain growth and network formation simultaneously proceeded to form a three-dimensional network. The preferred reaction was determined by the type of comonomer, and the structure of the hydrogel was changed accordingly. When AA or AAm was used as a comonomer, polymer growth and crosslinking proceeded together, so a hydrogel with increased peel strength and tensile strength could be prepared. In particular, in the case of AA, it was possible to prepare a hydrogel with improved adhesion without sacrificing ionic conductivity. When the molar ratio of AA to AMPS was 3.18, the 90° peel strength of AMPS hydrogel increased from 171 to 428 gf/25 mm, and ionic conductivity slightly decreased, from 0.93 to 0.84 S/m. By copolymerisation with HEA, polymer growth was preferred compared with chain crosslinking, and a hydrogel with lower peel strength, swelling ratio, and ionic conductivity than the pristine AMPS hydrogel was obtained.

Intraoperative mild hyperoxia may be associated with improved survival after off-pump coronary artery bypass grafting: a retrospective observational study.

BACKGROUND: The effect of hyperoxia due to supplemental oxygen administration on postoperative outcomes in patients undergoing cardiac surgery remains unclear. This retrospective study aimed to evaluate the relationship between intraoperative oxygen tension and mortality after off-pump coronary artery bypass grafting (OPCAB). METHODS: The study included adult patients who underwent isolated OPCAB between July 2010 and June 2020. Patients were categorised into three groups based on their intraoperative time-weighted average arterial oxygen partial pressure (PaO2): normoxia/near-normoxia (< 150 mmHg), mild hyperoxia (150-250 mmHg), and severe hyperoxia (> 250 mmHg). The risk of in-hospital mortality was compared using weighted logistic regression analysis. Restricted cubic spline analysis was performed to analyse intraoperative PaO2 as a continuous variable. The risk of cumulative all-cause mortality was compared using Cox regression analysis. RESULTS: The normoxia/near-normoxia, mild hyperoxia, and severe hyperoxia groups included 229, 991, and 173 patients (n = 1393), respectively. The mild hyperoxia group had a significantly lower risk of in-hospital mortality than the normoxia/near-normoxia (odds ratio [OR], 0.12; 95% confidence interval [CI], 0.06-0.22) and severe hyperoxia groups (OR, 0.06; 95% CI, 0.03-0.14). Intraoperative PaO2 exhibited a U-shaped relationship with in-hospital mortality in the non-hypoxic range. The risk of cumulative all-cause mortality was significantly lower in the mild hyperoxia group (hazard ratio, 0.72; 95% CI, 0.52-0.99) than in the normoxia/near-normoxia group. CONCLUSIONS: Maintaining intraoperative PaO2 at 150-250 mmHg was associated with a lower risk of mortality after OPCAB than PaO2 at < 150 mmHg and at > 250 mmHg. Future randomised trials are required to confirm if mildly increasing arterial oxygen tension during OPCAB to 150-250 mmHg improves postoperative outcomes.

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.

Relationship between intraoperative dopamine infusion and postoperative acute kidney injury in patients undergoing open abdominal aorta aneurysm repair.

BACKGROUND: Acute kidney injury (AKI) is one of the most common complications in patients undergoing open abdominal aortic aneurysm (AAA) repair. Dopamine has been frequently used in these patients to prevent AKI. We aimed to clarify the relationship between intraoperative dopamine infusion and postoperative AKI in patients undergoing open AAA repair. METHODS: We analyzed 294 patients who underwent open AAA repair at a single tertiary center from 2009 to 2018, retrospectively. The primary outcome was the incidence of postoperative AKI, determined by the Kidney Disease Improving Global Outcomes definition, after open AAA repair. Secondary outcomes included survival outcome, hospital and intensive care unit length of stay, and postoperative renal replacement therapy (RRT). RESULTS: Postoperative AKI occurred in 21.8% (64 out of 294 patients) The risk of postoperative AKI by intraoperative dopamine infusion was greater after adjusting for risk factors (odds ratio [OR] 2.56; 95% confidence interval [CI], 1.09-5.89; P = 0.028) and after propensity score matching (OR 3.22; 95% CI 1.12-9.24; P = 0.030). On the contrary, intraoperative norepinephrine use was not associated with postoperative AKI (use vs. no use; 19.3 vs. 22.4%; P = 0.615). Patients who used dopamine showed higher requirement for postoperative RRT (6.8 vs. 1.2%; P = 0.045) and longer hospital length of stay (18 vs. 16 days, P = 0.024). CONCLUSIONS: Intraoperative dopamine infusion was associated with more frequent postoperative AKI, postoperative RRT, and longer hospital length of stay in patients undergoing AAA repair, when compared to norepinephrine. Further prospective randomized clinical trial may be necessary for this topic.

Increased preoperative serum vitamin B12 level as a predictor of postoperative mortality in patients undergoing cardiac surgery.

BACKGROUND: Serum vitamin B12 level is a useful prognostic marker for various conditions. The present study examined whether preoperative serum vitamin B12 level can predict mortality after cardiac surgery. METHODS: The present observational study comprised adult patients who underwent cardiac surgery at our institute between 2012 and 2019. The performance of preoperative vitamin B12 level in discriminating postoperative in-hospital mortality, the primary outcome of this study, was assessed by receiver operating characteristic (ROC) curve analysis. After dichotomizing vitamin B12 level using Youden's J Index, weighted logistic regression analysis was performed. Cumulative all-cause mortality, the secondary outcome, was also compared using the Kaplan-Meier estimator and Cox regression analysis. RESULTS: A total of 973 patients were analyzed. The area under the ROC curve of vitamin B12 level for predicting in-hospital mortality was 0.76 (95% confidence interval [CI]: 0.73-0.78). Weighted logistic regression analysis revealed that the high vitamin B12 group (>726 pg/mL) had a significantly increased risk of in-hospital mortality compared to the low vitamin B12 group (adjusted odds ratio, 12.01; 95% CI: 7.73-18.67). The risk of mortality was higher in the high vitamin B12 group than the low vitamin B12 group (log-rank test, P<0.001; adjusted hazard ratio, 2.41; 95% CI: 1.70-2.39). In addition, the high vitamin B12 group had significantly poorer survival than the low vitamin B12 group, even within the same EuroSCORE II stratum (< or ≥4%; log-rank test, P<0.001 and P=0.001, respectively). CONCLUSIONS: Preoperative measurement of serum vitamin B12 level may be an alternative for predicting the prognosis of patients undergoing cardiac surgery.

Effects of transcutaneous electrical nerve stimulation on myocardial protection in patients undergoing aortic valve replacement: a randomized clinical trial.

BACKGROUND: Cardiopulmonary bypass-related myocardial ischemia-reperfusion injury is a major contributor to postoperative morbidity. Although transcutaneous electrical nerve stimulation (TENS) has been found to have cardioprotective effects in animal studies and healthy volunteers, its effects on cardiac surgery under cardiopulmonary bypass patients have not been evaluated. We investigated the effects of TENS on myocardial protection in patients undergoing aortic valve replacement surgery using cardiopulmonary bypass. METHODS: Thirty patients were randomized to receive TENS or sham in three different anesthetic states - pre-anesthesia, sevoflurane, or propofol (each n = 5). TENS was applied with a pulse width of 385 µs and a frequency of 10 Hz using two surface electrodes at the upper arm for 30 min. Sham treatment was provided without stimulation. The primary outcome was the difference in myocardial infarct size following ischemia-reperfusion injury in rat hearts perfused with pre- and post-TENS plasma dialysate obtained from the patients using Langendorff perfusion system. The cardioprotective effects of TENS were determined by assessing reduction in infarct size following treatment. RESULTS: There were no differences in myocardial infarct size between pre- and post-treatment in any group (41.4 ± 4.3% vs. 36.7 ± 5.3%, 39.8 ± 7.3% vs. 27.8 ± 12.0%, and 41.6 ± 2.2% vs. 37.8 ± 7.6%; p = 0.080, 0.152, and 0.353 in the pre-anesthesia, sevoflurane, and propofol groups, respectively). CONCLUSIONS: In our study, TENS did not show a cardioprotective effect in patients undergoing aortic valve replacement surgery. TRIAL REGISTRATION: This study was registered at clinicaltrials.gov ( NCT03859115 , on March 1, 2019).

Performance of the ACEF and ACEF II risk scores in predicting mortality after off-pump coronary artery bypass grafting.

STUDY OBJECTIVE: The age, creatinine, and ejection fraction (ACEF) I and II scores are known to predict operative mortality after cardiac surgery. However, data from few cases of off-pump coronary artery bypass grafting (OPCAB) were considered during the development of these scores. This study aimed to validate and update the ACEF I and II scores for the prediction of in-hospital mortality after OPCAB. DESIGN: Single-center retrospective observational study. SETTING: Tertiary university hospital. PATIENTS: All adult patients (≥18 years) who underwent isolated OPCAB between 2011 and 2020 were included in our analysis. MEASUREMENTS: Predicted in-hospital mortality after OPCAB was calculated using ACEF and ACEF II scores. Performance of ACEF I and II scores in predicting in-hospital mortality after OPCAB was evaluated using receiver operating characteristics curves and calibration plots. Scores were recalibrated and modified using the closed testing procedure and multivariable fractional polynomial analysis. MAIN RESULTS: In total, 1450 patients were analyzed. The ACEF I and II scores discriminated in-hospital mortality with the c-statistics of 0.86 and 0.83, respectively. The calibration plots revealed that both scores overestimated the risk of in-hospital mortality. The ACEF I score was recalibrated by re-estimating only the model intercept. The ACEF II score was modified by substituting hematocrit with left main coronary artery disease. The c-statistic of the updated ACEF II score increased to 0.86. Both the updated ACEF I and II scores were well-calibrated. CONCLUSIONS: The ACEF I and II scores discriminated in-hospital mortality after OPCAB with excellent accuracy, although calibration properties were suboptimal. The updated scores showed even better discrimination and calibration. Thus, the ACEF I and ACEF II scores can be relatively straightforward and useful tools for prognostication of patients undergoing OPCAB.

Association Between Abdominal Fat and Mortality in Patients Undergoing Cardiovascular Surgery.

BACKGROUND: Obesity is associated with reduced postoperative mortality among patients undergoing cardiovascular surgery. However, body mass index cannot differentiate abdominal fat composition. This study evaluated the relationships between total abdominal, subcutaneous, and visceral fat composition and postoperative mortality in East Asian patients undergoing cardiovascular surgery. METHODS: Adult patients who underwent cardiovascular surgery between October 2004 and December 2016 were retrospectively included. Total, subcutaneous, and visceral fat areas were measured from cross-sectional computed tomography images. The relationships between each fat composition and mortality were evaluated. RESULTS: In all, 3661 patients were analyzed, and overall mortality was 19.9% (729 died) during the 4.6-year median follow-up period. The risks of all-cause and cardiac-cause mortality decreased as subcutaneous fat composition increased (adjusted hazard ratio 0.997; 95% confidence interval, 0.994 to 1.000; and adjusted hazard ratio 0.994; 95% confidence interval, 0.989 to 0.999; P = .02 and P = .01, respectively). No association was detected between the total and visceral fat area and mortality. CONCLUSIONS: Reduced abdominal subcutaneous fat, but not the total or visceral fat composition, was associated with higher all-cause and cardiac-cause mortality after cardiovascular surgery in East Asian patients, consisting mainly of normal weight or overweight patients.