Volatile Anesthetic Use Versus Total Intravenous Anesthesia for Patients Undergoing Heart Valve Surgery: A Nationwide Population-Based Study.

BACKGROUND: Many studies have suggested that volatile anesthetic use may improve postoperative outcomes after cardiac surgery compared to total intravenous anesthesia (TIVA) owing to its potential cardioprotective effect. However, the results were inconclusive, and few studies have included patients undergoing heart valve surgery. METHODS: This nationwide population-based study included all adult patients who underwent heart valve surgery between 2010 and 2019 in Korea based on data from a health insurance claim database. Patients were divided based on the use of volatile anesthetics: the volatile anesthetics or TIVA groups. After stabilized inverse probability of treatment weighting (IPTW), the association between the use of volatile anesthetics and the risk of cumulative 1-year all-cause mortality (the primary outcome) and cumulative long-term (beyond 1 year) mortality were assessed using Cox regression analysis. RESULTS: Of the 30,755 patients included in this study, the overall incidence of 1-year mortality was 8.5%. After stabilized IPTW, the risk of cumulative 1-year mortality did not differ in the volatile anesthetics group compared to the TIVA group (hazard ratio, 0.98; 95% confidence interval, 0.90-1.07; P = .602), nor did the risk of cumulative long-term mortality (hazard ratio, 0.98; 95% confidence interval, 0.93-1.04; P = .579) at a median (interquartile range) follow-up duration of 4.8 (2.6-7.6) years. CONCLUSIONS: Compared with TIVA, volatile anesthetic use was not associated with reduced postoperative mortality risk in patients undergoing heart valve surgery. Our findings indicate that the use of volatile anesthetics does not have a significant impact on mortality after heart valve surgery. Therefore, the choice of anesthesia type can be based on the anesthesiologists' or institutional preference and experience.

Comparison between head rotation and standard techniques for i-gel™ insertion: a randomized controlled trial.

BACKGROUND: This study evaluated the effect of head rotation on the first-attempt success rate of i-gel insertion, aiming to alleviate the effect of gravity on the tongue and reduce resistance between the device and the tongue. METHODS: Adult surgical patients were randomized to standard and head rotation technique groups. In the head rotation technique group, patients' heads were maximally rotated to the left before i-gel insertion. The primary endpoint was the first-attempt success rate. Secondary endpoints included the success rate within two attempts (using the allocated technique), time required for successful i-gel placement within two attempts, and success rate at the third attempt (using the opposite technique). RESULTS: Among 158 patients, the head rotation technique group showed a significantly higher first-attempt success rate (60/80, 75.0%) compared to the standard technique group (45/78, 57.7%; P = 0.021). The success rate within two attempts was similar between the groups (95.0% vs. 91.0%, P = 0.326). The time required for successful i-gel placement was significantly shorter in the head rotation technique (mean [SD], 13.4 [3.7] s vs. 16.3 [7.8] s; P = 0.030). When the head rotation technique failed, the standard technique also failed in all cases (n = 4), whereas the head rotation technique succeeded in five out of the seven patients where the standard technique failed. CONCLUSIONS: The head rotation technique significantly improved the first-attempt success rate and reduced the time required for successful i-gel insertion. It was effective when the standard technique failed. The head rotation technique may be an effective primary or alternative method for i-gel insertion. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT05201339).

Association Between Individualized Versus Conventional Blood Glucose Thresholds and Acute Kidney Injury After Cardiac Surgery: A Retrospective Observational Study.

OBJECTIVES: This study was designed to compare individualized and conventional hyperglycemic thresholds for the risk of acute kidney injury (AKI) after cardiac surgery. DESIGN: This was an observational study. SETTING: The study took place in a single-center tertiary teaching hospital. PARTICIPANTS: Adult patients who underwent cardiac surgery between January 2012 and November 2021 were enrolled. MEASUREMENTS AND MAIN RESULTS: Two blood glucose thresholds were used to define intraoperative hyperglycemia. While the conventional hyperglycemic threshold (CHT) was 180 mg/dL in all patients, the individualized hyperglycemic threshold (IHT) was calculated based on the preoperative hemoglobin A1c level. Various metrics of intraoperative hyperglycemia were calculated using both thresholds: any hyperglycemic episode, duration of hyperglycemia, and area above the thresholds. Postoperative AKI associations were compared using receiver operating characteristic curves and logistic regression analysis. Among the 2,427 patients analyzed, 823 (33.9%) developed AKI. The C-statistics of IHT-defined metrics (0.58-0.59) were significantly higher than those of the CHT-defined metrics (all C-statistics, 0.54; all p < 0.001). The duration of hyperglycemia (adjusted odds ratio, 1.09; 95% confidence interval, 1.02-1.16) and area above the IHT (1.003; 1.001-1.004) were significantly associated with the risk of AKI, except for the presence of any hyperglycemic episode. None of the CHT-defined metrics were significantly associated with the risk of AKI. CONCLUSIONS: Individually defined intraoperative hyperglycemia better predicted postcardiac surgery AKI than universally defined hyperglycemia. Intraoperative hyperglycemia was significantly associated with the risk of AKI only for the IHT. Target blood glucose levels in cardiac surgical patients may need to be individualized based on preoperative glycemic status.

Differences in Brain Metabolite Profiles Between Normothermia and Hypothermia.

BACKGROUND: This study evaluated the difference in brain metabolite profiles between normothermia and hypothermia reaching 25°C in humans in vivo. METHODS: Thirteen patients who underwent thoracic aorta surgery under moderate hypothermia were prospectively enrolled. Plasma samples were collected simultaneously from the arteries and veins to estimate metabolite uptake or release. Targeted metabolomics based on liquid chromatographic mass spectrometry and direct flow injection were performed, and changes in the profiles of respective metabolites from normothermia to hypothermia were compared. The ratios of metabolite concentrations in venous blood samples to those in arterial blood samples (V/A ratios) were calculated, and log2 transformation of the ratios [log2(V/A)] was performed for comparison between the temperature groups. RESULTS: Targeted metabolomics were performed for 140 metabolites, including 20 amino acids, 13 biogenic amines, 10 acylcarnitines, 82 glycerophospholipids, 14 sphingomyelins, and 1 hexose. Of the 140 metabolites analyzed, 137 metabolites were released from the brain in normothermia, and the release of 132 of these 137 metabolites was decreased in hypothermia. Two metabolites (dopamine and hexose) showed constant release from the brain in hypothermia, and 3 metabolites (2 glycophospholipids and 1 sphingomyelin) showed conversion from release to uptake in hypothermia. Glutamic acid demonstrated a distinct brain metabolism in that it was taken up by the brain in normothermia, and the uptake was increased in hypothermia. CONCLUSION: Targeted metabolomics demonstrated various degrees of changes in the release of metabolites by the hypothermic brain. The release of most metabolites was decreased in hypothermia, whereas glutamic acid showed a distinct brain metabolism.

Comparison of recovery profiles between total intravenous anaesthesia with propofol or remimazolam reversed with flumazenil in patients undergoing breast surgery: A randomised controlled trial.

BACKGROUND: Remimazolam, a short acting benzodiazepine, is being used for general anaesthesia. The results of studies comparing recovery after propofol with that of remimazolam are inconsistent. Given that flumazenil reverses the sedative effects of remimazolam, we hypothesised that it would speed up recovery from remimazolam general anaesthesia. OBJECTIVES: The aim of this trial was to compare the speed of recovery from general anaesthesia between propofol and remimazolam reversed with flumazenil in patients undergoing minimally invasive breast surgery. DESIGN: Randomised, single-centre, double-blind controlled trial. SETTING: A tertiary teaching hospital in South Korea from August 2022 to December 2022. PATIENTS: Adult patients (≥19 years of age) about to undergo general anaesthesia for scheduled breast cancer surgery. INTERVENTIONS: Patients were randomly allocated to either the propofol or the remimazolam/flumazenil group. The emergence process was monitored by only one anaesthesiologist. MAIN OUTCOME MEASURES: The primary outcome was the time to eye opening to command during recovery from the general anaesthesia. Time to removal of the supraglottic airway (SGA) time to discharge, and the Riker sedation agitation scale (SAS) score (1 to 4) during emergence were compared as secondary outcomes. RESULTS: The remimazolam group had a significantly shorter mean time to eye opening than the propofol group [127 ±â€Š51 vs. 314 ±â€Š140 s; mean difference 187 s (95% confidence interval (CI), 133 to 241 s; P  < 0.001]. The remimazolam group also had shorter times to SGA removal [169 ±â€Š51 vs. 366 ±â€Š149 s; mean difference 198 s (95% CI, 140 to 255 s); P  < 0.001] and time to discharge from the operating room [243 ±â€Š55 vs. 449 ±â€Š159 s; mean difference 206 s (95% CI, 145 to 267 s); P  < 0.001]. The SAS scores during emergence also differed significantly, with 1 patient in the propofol group and 25 in the remimazolam group attaining scores of 4 ( P  < 0.001). CONCLUSION: Administration of remimazolam with flumazenil may be a promising option for patients undergoing breast cancer surgery, providing faster recovery and better SAS scores than propofol during emergence from general anaesthesia. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05435911).

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).

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.

Association Between Preoperative Fibrinogen-to-Albumin Ratio and All-Cause Mortality After Off-Pump Coronary Artery Bypass Grafting: A Retrospective Observational Study.

BACKGROUND: The fibrinogen-to-albumin ratio (FAR) is a recently introduced prognostic marker for patients with coronary artery disease. The present study investigated whether the FAR is associated with clinical outcome after off-pump coronary artery bypass grafting (OPCAB). METHODS: We retrospectively reviewed 1759 patients who underwent OPCAB (median duration of follow-up, 46 months). To evaluate the association between FAR and mortality in OPCAB patients, time-dependent coefficient Cox regression analyses were used to assess the association between FAR and all-cause mortality. RESULTS: In multivariable time-dependent coefficient Cox regression analyses, preoperative FAR was an independent risk factor for all-cause mortality after OPCAB (adjusted hazard ratio, 1.051; 95% confidence interval, 1.021-1.082). In the restricted cubic spline function curve of the multivariable-adjusted relationship between the preoperative FARs, a linear increase in the relative hazard for all-cause mortality was observed as the FAR increased (P = .001). CONCLUSIONS: A higher FAR is associated with increased all-cause mortality after OPCAB. The preoperative FAR could be a prognostic factor for predicting higher mortality after OPCAB.

Effects of remote ischemic preconditioning on platelet activation and reactivity in patients undergoing cardiac surgery using cardiopulmonary bypass: a randomized controlled trial.

During cardiopulmonary bypass (CPB), platelet activation and dysfunction are associated with adverse outcomes. Remote ischemic preconditioning (RIPC) has been shown to attenuate platelet activation. We evaluated the effects of RIPC on platelet activation during CPB in patients undergoing cardiac surgery. Among 58 randomized patients, 26 in the RIPC group and 28 in the sham-RIPC group were analyzed. RIPC consisted of 4 cycles of 5-min ischemia induced by inflation of pneumatic cuff pressure to 200 mmHg, followed by 5-min reperfusion comprising deflation of the cuff on the upper arm. Platelet activation was assessed using flow cytometry analysis of platelet activation markers. The primary endpoint was the AUC of CD62P expression during the first 3 h after initiation of CPB. Secondary outcomes were the AUC of PAC-1 expression and monocyte-platelet aggregates (MPA) during 3 h of CPB. The AUCs of CD62P expression during 3 h after initiation of CPB were 219.4 ± 43.9 and 211.0 ± 41.2 MFI in the RIPC and sham-RIPC groups, respectively (mean difference, 8.42; 95% CI, -14.8 and 31.7 MFI; p =.471). The AUCs of PAC-1 expression and MPA did not differ between groups. RIPC did not alter platelet activation and reactivity during CPB in 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).

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.

Heart rate variability and oxygen reserve index during cardiorespiratory events in patients undergoing ophthalmic arterial chemotherapy: a prospective observational study.

Unexpected cardiorespiratory compromise has been reported during ophthalmic arterial chemotherapy in pediatric patients with retinoblastoma. Although the underlying mechanisms remain unclear, autonomic responses are presumed to contribute to these events. We hypothesized that periprocedural heart rate variability would differ between patients with and without events. Between April 2018 and September 2019, 38 patients (age under 7 years) were included. Heart rate variability was analyzed using electrocardiogram, and oxygen reserve index was also monitored. Cardiorespiratory events were defined as > 30% changes in blood pressure or heart rate, > 20% changes in end-tidal carbon dioxide, > 40% changes in peak inspiratory pressure, or pulse oxygen saturation < 90% during ophthalmic artery catheterization. Heart rate variability and oxygen reserve index were compared between patients with and without cardiorespiratory events. Cardiorespiratory events occurred in 13/38 (34%) patients. During the events, end-tidal carbon dioxide was significantly lower (median difference [95% CI], - 2 [- 4 to - 1] mmHg, p = 0.006) and the maximum peak inspiratory pressure was higher (30 [25-37] vs. 15 [14-16] hPa, p < 0.001), compared to patients without events. Standard deviation of normal-to-normal R-R interval, total power, and very low-frequency power domain increased during selection of the ophthalmic artery in patients with events (all adjusted p < 0.0001), without predominancy of specific autonomic nervous alterations. Oxygen reserve index was significantly lower in patients with events than those without throughout the procedure (mean difference [95% CI], - 0.19 [- 0.32 to - 0.06], p = 0.005). Enhanced compensatory autonomic regulation without specific autonomic predominancy, and reduced oxygen reserve index was observed in patients with cardiorespiratory events than in patients without events.

Association Between Intraoperative Hyperoxia and Acute Kidney Injury After Cardiac Surgery: A Retrospective Observational Study.

OBJECTIVE: Optimal oxygen management during cardiac surgery has not been established, and studies on the effects of perioperative hyperoxia on postoperative acute kidney injury (AKI) are scarce. The association between intraoperative hyperoxia and AKI after cardiac surgery involving cardiopulmonary bypass was evaluated for the present study. DESIGN: Retrospective observational study. SETTING: A tertiary teaching hospital. PARTICIPANTS: Adult patients who underwent cardiac surgery with cardiopulmonary bypass from November 2006-December 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The area above arterial oxygen partial pressure (PaO2) threshold of 300 mmHg (AOT300, mmHg × h) was used as a metric of intraoperative hyperoxia and was associated with postoperative AKI, using the logistic regression analysis. Data also were fitted using the restricted cubic spline model. Sensitivity analyses were conducted using different PaO2 thresholds (150, 200, 250, and 350 mmHg). A total of 2,926 patients were analyzed. Intraoperative AOT300 independently was associated with the risk of AKI (odds ratio 1.0009; 95% confidence interval 1.0002-1.0015). A PaO2 increment of 100 mmHg above PaO2 300 mmHg for an hour was associated with an increased risk of AKI by 9.4% (1.0009100 ≈ 1.094). In the spline model, the log-odds of AKI increased as AOT300 increased. In the sensitivity analyses, AOT250 and AOT350 also significantly were associated with the risk of AKI, whereas AOT150 and AOT200 were not. As the PaO2 threshold increased from 150 to 350 mmHg, the odds ratio gradually increased. CONCLUSIONS: Intraoperative hyperoxia significantly was associated with the risk of AKI after cardiac surgery involving cardiopulmonary bypass.

Effect of Perioperative Subglottic Secretion Drainage on Ventilator-Associated Pneumonia After Cardiac Surgery: A Retrospective, Before-and-After Study.

OBJECTIVES: Although postoperative subglottic secretion drainage prevents ventilator-associated pneumonia (VAP) after cardiac surgery, its role during the perioperative period is unclear. For the present study, the effect of subglottic secretion drainage during and after cardiac surgery on postoperative VAP was investigated. DESIGN: Retrospective, single-center, before-and-after study. SETTING: Perioperative care of cardiac surgical patients in a tertiary university hospital. PARTICIPANTS: Adult patients who underwent cardiac surgery from January 2013-December 2018. INTERVENTIONS: Conventional and subglottic suctioning endotracheal tubes were used in the control and intervention groups before and after a change in institutional policy, respectively. In the intervention group, subglottic secretion drainage was performed continuously during surgery and intermittently after surgery. MEASUREMENTS AND MAIN RESULTS: The risk of postoperative VAP, identified by the National Healthcare Safety Network surveillance definition algorithm, was compared by weighted logistic regression. Logistic regression analyses, with propensity score matching and inverse probability weighting, also were performed. A total of 2,576 patients were analyzed (control [n = 2108]; intervention [n = 468]). Postoperative VAP occurred less frequently in the intervention group (1/468 [0.2%]) compared with the control group (30/2,108 [1.4%]). In the multivariate weighted logistic regression analysis, the risk of VAP after cardiac surgery was significantly lower in the intervention group than in the control group (odds ratio 0.29; 95% confidence interval 0.14-0.58). Similar results were obtained in multivariate analyses after propensity score matching (odds ratio 0.04; 95% confidence interval 0.01-0.14) and inverse probability weighting (odds ratio 0.16; 95% confidence interval 0.05-0.42). CONCLUSIONS: Routine perioperative subglottic secretion drainage using subglottic suctioning endotracheal tubes in patients undergoing cardiac surgery was associated with a reduction in the risk of VAP after surgery.

Effects of anesthetics on microvascular reactivity measured by vascular occlusion tests during off-pump coronary artery bypass surgery: a randomized controlled trial.

Microvascular function may be modulated by various anesthetics. Desflurane and propofol anesthesia have different effects on microvascular function. However, there are few reports on the effects of sevoflurane and desflurane on microvascular function during cardiac surgery. We compared the effects of sevoflurane and desflurane on microvascular reactivity, as measured by the vascular occlusion tests (VOTs) during off-pump coronary artery bypass (OPCAB) surgery. Patients undergoing OPCAB were eligible for study inclusion. Patients were excluded if they were unsuitable for treatment with volatile agents or the VOT, had renal failure or uncontrolled diabetes, or were pregnant. The enrolled patients were randomized to receive sevoflurane or desflurane during surgery. Tissue oxygen saturation (StO2) dynamics during the VOT were measured at baseline (pre-anesthesia), pre-anastomosis, post-anastomosis of vessel grafts, and at the end of surgery. Macrohemodynamic variables, arterial blood gas parameters, and in-hospital adverse events were also evaluated. A total of 64 patients (32 in each group) were analyzed. StO2 dynamics did not differ between the groups. Compared to baseline, StO2 and the rate of recovery following vascular occlusion decreased at the end of surgery in both groups (adjusted p-value, < 0.001), and no group difference was observed. Macrohemodynamic variables, blood gas analysis results, and the rate of postoperative in-hospital adverse events were similar between the groups. Microvascular reactivity, as measured by the VOT during OPCAB, showed no difference between the sevoflurane and desflurane groups. Also, there were no group differences in macrohemodynamics or the rate of postoperative adverse events. TRIAL REGISTRATION : Clinicaltrials.gov, identifier NCT03209193; registered on July 3, 2017.

Intraoperative hyperglycemia in patients with an elevated preoperative C-reactive protein level may increase the risk of acute kidney injury after cardiac surgery.

PURPOSE: The effect of hyperglycemia on acute kidney injury (AKI) in patients undergoing cardiac surgery is unclear and may involve as yet unexplored factors. We hypothesized differential effects of intraoperative hyperglycemia on AKI after cardiac surgery depending on baseline inflammatory status, as reflected by the C-reactive protein (CRP) level. METHODS: This retrospective study included patients who underwent cardiac surgery seen at our hospital from 2008 to 2018. Patients were classified into four groups according to their preoperative CRP level (≥ 1 or < 1 mg/dl) and their intraoperative time-weighted average glucose concentration (> 140 or ≤ 140 mg/dl): low CRP and normoglycemia, low CRP and hyperglycemia, high CRP and normoglycemia, and high CRP and hyperglycemia. The data were analyzed by multivariable logistic regression analysis. RESULTS: The data of 3625 patients were analyzed. The logistic regression showed that patients in the high CRP and hyperglycemia group had a significantly higher risk of AKI than patients in the low CRP and normoglycemia group [odds ratio (OR), 1.58; 95% confidence interval (CI) 1.10-2.27], low CRP with hyperglycemia group (OR, 1.69; 95% CI 1.16-2.47) and high CRP with normoglycemia group (OR, 1.50; 95% CI 1.01-2.23). CONCLUSIONS: Intraoperative hyperglycemia in patients with an elevated preoperative CRP level was significantly related to an increased risk of AKI after cardiac surgery. Individualized perioperative glycemic control may therefore be necessary in these patients.

The impact of total intravenous anesthesia versus inhalation anesthesia on acute kidney injury after major abdominal surgery: a propensity score analysis.

PURPOSE: The effect of anesthetic types on postoperative acute kidney injury (AKI) remains unclear particularly in patients undergoing non-cardiac surgery. The purpose of this retrospective study was to compare total intravenous anesthesia (TIVA) and inhalation anesthesia in terms of the risk of AKI after open major abdominal surgery (MAS). METHODS: Adult patients who underwent open MAS (gastrectomy, hepatectomy, colectomy, or pancreatectomy) at our institute from 2016 to 2018 were included. Using the multivariable logistic regression, the risk of postoperative AKI was compared among patients who underwent TIVA (TIVA group) and inhalation anesthesia (inhalation group) both in the total cohort and in the propensity score-matched cohort. Additional multivariable logistic regression analysis was performed with inverse probability of treatment weighting (IPTW) using the propensity score. RESULTS: In total, 3616 patients were analyzed. The incidence of postoperative AKI was 5.0% (77/1546) and 7.8% (161/2070) in the TIVA and inhalation groups, respectively. The risk of AKI was significantly higher in the inhalation group [adjusted odds ratio (aOR) 1.72; 95% confidence interval (CI) 1.27-2.35; P = 0.002] than the TIVA group. In the matched cohort (n = 1518 in each group), the inhalation group also had a higher risk of AKI (aOR 1.66; 95% CI 1.20-2.31; P = 0.002). The multivariable logistic regression with IPTW showed similar results (aOR 1.59; 95% CI 1.30-1.95; P < 0.001). CONCLUSIONS: The risk of AKI after open MAS differed significantly according to the anesthetic used. Patients receiving inhalation anesthesia may have a greater risk of postoperative AKI than those undergoing TIVA.

Impact of Mitral Valve Repair Case Volume on Postoperative Mortality　- A Nationwide Korean Cohort Study.

BACKGROUND: Although mitral valve repair is recommended over replacement due to better outcomes, repair rates vary significantly among centers. This study examined the effect of institutional mitral valve repair volume on postoperative mortality.Methods and Results:All cases of adult mitral valve repair performed in Korea between 2009 and 2016 were analyzed. The association between case volume and 1-year mortality was analyzed after categorizing centers according to the number of mitral valve repairs performed as low-, medium-, or high-volume centers (<20, 20-40, and >40 cases/year, respectively). The effect of case volume on cumulative all-cause mortality was also assessed. In all, 6,041 mitral valve repairs were performed in 86 centers. The 1-year mortality in low-, medium-, and high-volume centers was 10.1%, 8.7%, and 4.7%, respectively. Low- and medium-volume centers had increased risk of 1-year mortality compared with high-volume centers, with odds ratios of 2.80 (95% confidence interval [CI] 2.15-3.64; P<0.001) and 2.66 (95% CI 1.94-3.64; P<0.001), respectively. The risk of cumulative all-cause mortality was also worse in low- and medium-volume centers, with hazard ratios of 1.96 (95% CI 1.68-2.29; P<0.001) and 1.77 (95% CI 1.47-2.12; P<0.001), respectively. CONCLUSIONS: Lower institutional case volume was associated with higher mortality after mitral valve repair. A minimum volume standard may be required for hospitals performing mitral valve repair to guarantee adequate outcome.

Association Between Postoperative Body Temperature and All-Cause Mortality After Off-Pump Coronary Artery Bypass Graft Surgery: A Retrospective Observational Study.

BACKGROUND: Inadvertent perioperative hypothermia is common in patients undergoing off-pump coronary artery bypass grafting (OPCAB). We investigated the association between early postoperative body temperature and all-cause mortality in patients undergoing OPCAB. METHODS: We reviewed the electronic medical records of 1714 patients who underwent OPCAB (median duration of follow-up, 47 months). Patients were divided into 4 groups based on body temperature at the time of intensive care unit admission after surgery (moderate-to-severe hypothermia, <35.5°C; mild hypothermia, 35.5°C-36.5°C; normothermia, 36.5°C-37.5°C; and hyperthermia, ≥37.5°C). Cox proportional hazards models were used to assess the association between body temperature and all-cause mortality. The association between early postoperative changes in body temperature and all-cause mortality was also assessed by dividing the patients into 4 categories according to the body temperature measured at postoperative intensive care unit admission and the average body temperature during the first 3 postoperative days. RESULTS: Compared to the normothermia group, the adjusted hazard ratios of all-cause mortality were 2.030 (95% confidence interval, 1.407-2.930) in the moderate-to-severe hypothermia group and 1.445 (95% confidence interval, 1.113-1.874) in the mild hypothermia group. Patients who were hypothermic at postoperative intensive care unit admission but attained normothermia thereafter were at a lower risk of all-cause mortality compared to patients who did not regain normothermia (adjusted hazard ratio, 0.631; 95% confidence interval, 0.453-0.878), while they were still at a higher risk of all-cause mortality than those who were consistently normothermic (adjusted hazard ratio, 1.435; 95% confidence interval, 1.090-1.890). CONCLUSIONS: Even mild early postoperative hypothermia was associated with all-cause mortality after OPCAB. Patients who regained normothermia postoperatively were at lower risk of all-cause mortality compared to those who did not.

The relationship between intraoperative cerebral oximetry and postoperative delirium in patients undergoing off-pump coronary artery bypass graft surgery: a retrospective study.

BACKGROUND: Cerebral oximetry has been widely used to measure regional oxygen saturation in brain tissue, especially during cardiac surgery. Despite its popularity, there have been inconsistent results on the use of cerebral oximetry during cardiac surgery, and few studies have evaluated cerebral oximetry during off pump coronary artery bypass graft surgery (OPCAB). METHODS: To evaluate the relationship between intraoperative cerebral oximetry and postoperative delirium in patients who underwent OPCAB, we included 1439 patients who underwent OPCAB between October 2004 and December 2016 and among them, 815 patients with sufficient data on regional cerebral oxygen saturation (rSO2) were enrolled in this study. We retrospectively analyzed perioperative variables and the reduction in rSO2 below cut-off values of 75, 70, 65, 60, 55, 50, 45, 40, and 35%. Furthermore, we evaluated the relationship between the reduction in rSO2 and postoperative delirium. RESULTS: Delirium occurred in 105 of 815 patients. In both univariable and multivariable analyses, the duration of rSO2 reduction was significantly longer in patients with delirium at cut-offs of < 50 and 45% (for every 5 min, adjusted odds ratio (OR) 1.007 [95% Confidence interval (CI) 1.001 to 1.014] and adjusted OR 1.012 [1.003 to 1.021]; p = 0.024 and 0.011, respectively). The proportion of patients with a rSO2 reduction < 45% was significantly higher among those with delirium (adjusted OR 1.737[1.064 to 2.836], p = 0.027). CONCLUSIONS: In patients undergoing OPCAB, intraoperative rSO2 reduction was associated with postoperative delirium. Duration of rSO2 less than 50% was 40% longer in the patients with postoperative delirium. The cut-off value of intraoperative rSO2 that associated with postoperative delirium was 50% for the total patient population and 55% for the patients younger than 68 years.