The effect of intraoperative positive end expiratory pressure and tidal volume on postoperative acute kidney injury after orthopedic surgery.

BACKGROUND: To test whether higher intraoperative PEEP levels and/or higher TV levels are associated with higher incidence of postoperative AKI within the first postoperative week, in adult patients having orthopedic surgeries under general anesthesia. METHODS: We conducted a sub analysis of a non-randomized alternating intervention cross over study performed in patients undergoing orthopedic surgery under general anesthesia at Cleveland Clinic, Cleveland, OH. We included four different combinations of PEEP (5 or 8 cm H2 O) and TV (6 or 10 mL/kg of PBW) that alternated each week in the six orthopedic operating rooms. Our primary outcome was postoperative AKI defined by the KDIGO criteria with baseline creatinine as the closest preoperative value to the time of surgery obtained within 30 days and postoperative value as the highest creatinine value within 7 days after surgery. Secondary outcome was the maximum postoperative in-hospital creatinine level within seven postoperative days. MAIN RESULTS: A total of 1933 patients were included in the analysis. The incidence of AKI was 6.8% in the study population and similar in high TV versus low TV group and high PEEP versus low PEEP group. Neither TV nor PEEP significantly impacted AKI incidence. The estimated odds ratio of AKI comparing TV = 6 mL/kg to TV = 10 mL/kg was 0.96 (97.5% CI: 0.63, 1.46; p = .811); while the estimated odds ratio of AKI comparing PEEP = 5cm H2 O to PEEP = 8cm H2 O was 0.92 (97.5% CI: 0.60, 1.39; p = .623). No interaction was found between TV and PEEP on AKI. Additionally, neither TV nor PEEP had a significant effect on the seven postoperative day creatinine levels. CONCLUSION: Higher levels of PEEP or TV during mechanical ventilation in adult patients undergoing orthopedic surgeries under general anesthesia do not increase the odds of developing postoperative AKI within the narrow limits studied.

Multiorgan talks in the presence of brain injury.

PURPOSE OF REVIEW: The brain is the command center of the rest of the body organs. The normal multiorgan talks between the brain and the rest of the body organs are essential for the normal body homeostasis. In the presence of brain injury, the disturbed talks between the brain and the rest of body organs will result in several pathological conditions. The aim of this review is to present the most recent findings for the pathological conditions that would result from the impaired multiorgan talks in the presence of brain injury. RECENT FINDINGS: The brain injury such as in acute ischemic stroke, subarachnoid hemorrhage and traumatic brain injury will result in cascade of pathological talks between the brain and the rest of body organs. These pathological talks could result in pathological conditions such as cardiomyopathy, acute lung and kidney injuries, impaired liver functions, and impaired gut barrier permeability as well. SUMMARY: Better understanding of the pathological conditions that could result from the impaired multiorgan talks in the presence of brain injury will open the doors for precise targeted therapies in the future for myriad of pathological conditions.

Risk Factors Associated With Postoperative Mortality Among COVID-19 Positive Patients: Results of 3027 Operations and Procedures.

OBJECTIVE: To investigate the predictors of postoperative mortality in coronavirus disease 2019 (COVID-19)-positive patients. BACKGROUND: COVID-19-positive patients have more postoperative complications. Studies investigating the risk factors for postoperative mortality in COVID-19-positive patients are limited. METHODS: COVID-19-positive patients who underwent surgeries/procedures in Cleveland Clinic between January 2020 and March 2021 were identified retrospectively. The primary outcome was postoperative/procedural 30-day mortality. Secondary outcomes were length of stay, intensive care unit admission, and 30-day readmission. RESULTS: A total of 2543 patients who underwent 3027 surgeries/procedures were included. Total 48.5% of the patients were male. The mean age was 57.8 (18.3) years. A total of 71.2% had at least 1 comorbidity. Total 78.7% of the cases were elective. The median operative time was 94 (47.0-162) minutes and mean length of stay was 6.43 (13.4) days. Postoperative/procedural mortality rate was 4.01%. Increased age [odds ratio (OR): 1.66, 95% CI, 1.4-1.98; P <0.001], being a current smoker [2.76, (1.3-5.82); P =0.008], presence of comorbidity [3.22, (1.03-10.03); P =0.043], emergency [6.35, (3.39-11.89); P <0.001] and urgent versus [1.78, (1.12-2.84); P =0.015] elective surgery, admission through the emergency department [15.97, (2.00-127.31); P =0.009], or inpatient service [32.28, (7.75-134.46); P <0.001] versus outpatients were associated with mortality in the multivariable analysis. Among all specialties, thoracic surgery [3.76, (1.66-8.53); P =0.002] had the highest association with mortality. Total 17.5% of the patients required intensive care unit admission with increased body mass index being a predictor [1.03, (1.01-1.05); P =0.005]. CONCLUSIONS: COVID-19-positive patients have higher risk of postintervention mortality. Risk factors should be carefully evaluated before intervention. Further studies are needed to understand the impact of pandemic on long-term surgical/procedural outcomes.

Postoperative Respiratory Failure After Elective Abdominal Surgery: A Case-Control Study.

INTRODUCTION: Postoperative respiratory failure (PRF) contributes significantly to morbidity and mortality. We sought to identify patient characteristics and perioperative risk factors associated with PRF in patients undergoing elective abdominal surgery to improve patient outcomes. METHODS: We retrospectively reviewed patients undergoing elective abdominal surgery from 2011 to 2016 at our institution. An experimental group consisting of adult patients with the Patient Safety Indicator 11 diagnosis of PRF was compared with a time-matched control group. RESULTS: Each group consisted of 233 patients. Comorbidities associated with PRF included ascites, coronary artery disease, chronic kidney disease, chronic obstructive pulmonary disease, diabetes mellitus type II, hypertension, and hypoalbuminemia (P < 0.05). American Society of Anesthesiologists score IV (20.2% versus 3.95%; P < 0.001), operative time (4.13 versus 2.55 h; P < 0.001), laparotomy with open operation (77.7% versus 45.5%; P < 0.001), and net intraoperative fluid balance (3635 versus 2410 mL; P < 0.001) were higher in patients with PRF. On multivariate analysis, age, American Society of Anesthesiologists score, chronic obstructive pulmonary disease, diabetes mellitus type II, laparotomy, and net intraoperative fluid balance maintained significance (P < 0.05). CONCLUSIONS: We identified contributing pre- and intra-operative risk factors for PRF undergoing elective abdominal surgery. These findings may help identify those at increased risk for respiratory failure and mitigate complications.

Oxygen Saturation and Postoperative Mortality in Patients With Acute Ischemic Stroke Treated by Endovascular Thrombectomy.

BACKGROUND: Monitored anesthesia care (MAC) and general anesthesia (GA) with endotracheal intubation are the 2 most used techniques for patients with acute ischemic stroke (AIS) undergoing endovascular thrombectomy. We aimed to test the hypothesis that increased arterial oxygen concentration during reperfusion period is a mechanism underlying the association between use of GA (versus MAC) and increased risk of in-hospital mortality. METHODS: In this retrospective cohort study, data were collected at the Cleveland Clinic between 2013 and 2018. To assess the potential mediation effect of time-weighted average oxygen saturation (Spo2) in first postoperative 48 hours between the association between GA versus MAC and in-hospital mortality, we assessed the association between anesthesia type and post-operative Spo2 tertiles (exposure-mediator relationship) through a cumulative logistic regression model and assessed the association between Spo2 and in-hospital mortality (mediator-outcome relationship) using logistic regression models. Confounding factors were adjusted for using propensity score methods. Both significant exposure-mediator and significant mediator-outcome relationships are needed to suggest potential mediation effect. RESULTS: Among 358 patients included in the study, 104 (29%) patients received GA and 254 (71%) received MAC, with respective hospital mortality rate of 19% and 5% (unadjusted P value <.001). GA patients were 1.6 (1.2, 2.1) (P < .001) times more likely to have a higher Spo2 tertile as compared to MAC patients. Patients with higher Spo2 tertile had 3.8 (2.1, 6.9) times higher odds of mortality than patients with middle Spo2 tertile, while patients in the lower Spo2 tertile did not have significant higher odds compared to the middle tertile odds ratio (OR) (1.8 [0.9, 3.4]; overall P < .001). The significant exposure-mediator and mediator-outcome relationships suggest that Spo2 may be a mediator of the relationship between anesthetic method and mortality. However, the estimated direct effect of GA versus MAC on mortality (ie, after adjusting for Spo2; OR [95% confidence interval {CI}] of 2.1 [0.9-4.9]) was close to the estimated association ignoring Spo2 (OR [95% CI] of 2.2 [1.0-5.1]), neither statistically significant, suggesting that Spo2 had at most a modest mediator role. CONCLUSIONS: GA was associated with a higher Spo2 compared to MAC among those treated by endovascular thrombectomy for AIS. Spo2 values that were higher than the middle tertile were associated with higher odds of mortality. However, GA was not significantly associated with higher odds of death. Spo2 at most constituted a modest mediator role in explaining the relationship between GA versus MAC and mortality.

Association Between Preoperative Statin Use and Respiratory Complications After Noncardiac Surgery: A Retrospective Cohort Analysis.

BACKGROUND: Statins possess pleiotropic effects, which potentially benefit noncardiovascular conditions. Previous work suggests that statins reduce inflammation and prevent acute respiratory distress syndrome and infections. However, there is a paucity of data regarding potential benefits of statins on respiratory and infectious complications, particularly after noncardiac surgery. We therefore evaluated respiratory and other complications in noncardiac surgery patients taking or not taking statins preoperatively. METHODS: We obtained data from the Cleveland Clinic Perioperative Health Documentation System and evaluated medical records of 92,139 inpatients who had noncardiac surgery. Among these, 31,719 patients took statins preoperatively. Statin patients were compared to nonstatin patients on incidence of intraoperative use of albuterol and postoperative respiratory complications for primary analysis. Infectious complications, cardiovascular complications, in-hospital mortality, and duration of hospitalization were compared for secondary analyses, using inverse probability of treatment weighting to control for potential confounding. RESULTS: Statin use was associated with lower odds of intraoperative albuterol treatment (odds ratio [OR] = 0.89; 97.5% confidence interval [CI], 0.82-0.97; P = .001; number needed to treat [NNT] = 216). Postoperative respiratory complications were also less common (OR = 0.82; 98.75% CI, 0.78-0.87; P < .001). Secondarily, statin use was associated with lower odds of infections, cardiovascular complications, in-hospital mortality, and shorter duration of hospitalization. The interaction between statin use and sex was significant (with significance criteria P < .10) for all primary and secondary outcomes except intraoperative use of albuterol. CONCLUSIONS: Preoperative statin use in noncardiac surgical patients was associated with slightly reduced odds of postoperative respiratory, infectious, and cardiovascular complications. However, the NNTs were high. Thus, despite the fact that statins appeared to be associated with lower odds of various complications, especially cardiovascular complications, our results do not support using statins specifically to reduce noncardiovascular complications after noncardiac surgery.

Sugammadex Versus Neostigmine for Reversal of Rocuronium Neuromuscular Block in Patients Having Catheter-Based Neurointerventional Procedures: A Randomized Trial.

BACKGROUND: Catheter-based endovascular neurointerventions require deep neuromuscular blocks during the procedure and rapid subsequent recovery of strength to facilitate neurological evaluation. We tested the primary hypothesis that sugammadex reverses deep neuromuscular blocks faster than neostigmine reverses moderate neuromuscular blocks. METHODS: Patients having catheter-based cerebral neurointerventional procedures were randomized to: (1) deep rocuronium neuromuscular block with posttetanic count 1 to 2 and 4-mg/kg sugammadex as the reversal agent or (2) moderate rocuronium neuromuscular block with train-of-four (TOF) count 1 during the procedure and neuromuscular reversal with 0.07-mg/kg neostigmine to a maximum of 5 mg. Recovery of diaphragmatic function was assessed by ultrasound at baseline before the procedure and 90 minutes thereafter. The primary outcome-time to reach a TOF ratio ≥0.9 after administration of the designated reversal agent-was analyzed with a log-rank test. Secondary outcomes included time to successful tracheal extubation and the difference between postoperative and preoperative diaphragmatic contraction speed and distance. RESULTS: Thirty-five patients were randomized to sugammadex and 33 to neostigmine. Baseline characteristics and surgical factors were well balanced. The median time to reach TOF ratio ≥0.9 was 3 minutes (95% confidence interval [CI], 2-3 minutes) in patients given sugammadex versus 8 minutes (95% CI, 6-10 minutes) in patients given neostigmine. Sugammadex was significantly faster by a median of 5 minutes (95% CI, 3-6 minutes; P < .001). However, times to tracheal extubation and diaphragmatic function at 90 minutes did not differ significantly. CONCLUSIONS: Sugammadex reversed deep rocuronium neuromuscular blocks considerably faster than neostigmine reversed moderate neuromuscular blocks. However, times to extubation did not differ significantly, apparently because extubation was largely determined by the time required for awaking from general anesthesia and because clinicians were willing to extubate before full neuromuscular recovery. Sugammadex may nonetheless be preferable to procedures that require a deep neuromuscular block and rapid recovery.

Machine Learning Models to Predict Major Adverse Cardiovascular Events After Orthotopic Liver Transplantation: A Cohort Study.

OBJECTIVE: To develop machine learning models that can predict post-transplantation major adverse cardiovascular events (MACE), all-cause mortality, and cardiovascular mortality in patients undergoing liver transplantation (LT). DESIGN: Retrospective cohort study. SETTING: High-volume tertiary care center. PARTICIPANTS: The study comprised 1,459 consecutive patients undergoing LT between January 2008 and December 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: MACE, all-cause mortality, and cardiovascular mortality were modeled using logistic regression, least absolute shrinkage and selection surgery regression, random forests, support vector machine, and gradient-boosted modeling (GBM). All models were built by splitting data into training and testing cohorts, and performance was assessed using five-fold cross-validation based on the area under the receiver operating characteristic curve and Harrell's C statistic. A total of 1,459 patients were included in the final cohort; 1,425 (97.7%) underwent index transplantation, 963 (66.0%) were female, the median age at transplantation was 57 (11-70) years, and the median Model for End-Stage Liver Disease score was 20 (6-40). Across all outcomes, the GBM model XGBoost achieved the highest performance, with an area under the receiver operating curve of 0.71 (95% confidence interval [CI] 0.63-0.79) for MACE, a Harrell's C statistic of 0.64 (95% CI 0.57-0.73) for overall survival, and 0.72 (95% CI 0.59-0.85) for cardiovascular mortality over a mean follow-up of 4.4 years. Examination of Shapley values for the GBM model revealed that on the cohort-wide level, the top influential factors for postoperative MACE were age at transplantation, diabetes, serum creatinine, cirrhosis caused by nonalcoholic steatohepatitis, right ventricular systolic pressure, and left ventricular ejection fraction. CONCLUSION: Machine learning models developed using data from a tertiary care transplantation center achieved good discriminant function in predicting post-LT MACE, all-cause mortality, and cardiovascular mortality. These models can support clinicians in recipient selection and help screen individuals who may be at elevated risk for post-transplantation MACE.

Association between Use of Angiotensin-converting Enzyme Inhibitors or Angiotensin Receptor Blockers and Postoperative Delirium.

BACKGROUND: Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers improve cognitive function. The authors therefore tested the primary hypothesis that preoperative use of angiotensin inhibitors is associated with less delirium in critical care patients. Post hoc, the association between postoperative use of angiotensin system inhibitors and delirium was assessed. METHODS: The authors conducted a single-site cohort study of adults admitted to Cleveland Clinic critical care units after noncardiac procedures between 2013 and 2018 who had at least one Confusion Assessment Method delirium assessment. Patients with preexisting dementia, Alzheimer's disease or other cognitive decline, and patients who had neurosurgical procedures were excluded. For the primary analysis, the confounder-adjusted association between preoperative angiotensin inhibitor use and the incidence of postoperative delirium was assessed. Post hoc, the confounder-adjusted association between postoperative angiotensin system inhibitor use and the incidence of delirium was assessed. RESULTS: The incidence of delirium was 39% (551 of 1,396) among patients who were treated preoperatively with angiotensin system inhibitors and 39% (1,344 of 3,468) in patients who were not. The adjusted odds ratio of experiencing delirium during critical care was 0.98 (95% CI, 0.86 to 1.10; P = 0.700) for preoperative use of angiotensin system inhibitors versus control. Delirium was observed in 23% (100 of 440) of patients who used angiotensin system inhibitors postoperatively before intensive care discharge, and in 41% (1,795 of 4,424) of patients who did not (unadjusted P < 0.001). The confounder-adjusted odds ratio for experiencing delirium in patients who used angiotensin system inhibitors postoperatively was 0.55 (95% CI, 0.43 to 0.72; P < 0.001). CONCLUSIONS: Preoperative use of angiotensin system inhibitors is not associated with reduced postoperative delirium. In contrast, treatment during intensive care was associated with lower odds of delirium. Randomized trials of postoperative angiotensin-converting enzymes inhibitors and angiotensin receptor blockers seem justified.

Association of Intraoperative Tidal Volumes and Acute Kidney Injury After Noncardiac Surgery.

BACKGROUND: Patients with acute lung injury who received lower tidal volume (VT) ventilation had significantly fewer days with acute kidney injury (AKI) when compared to those receiving higher VTs. There is a paucity of studies on the relationship between intraoperative VTs and postoperative AKI in patients undergoing noncardiac surgery. We therefore sought to assess the association of mean delivered intraoperative VT per kilogram based on predicted body weight (PBW) and postoperative AKI. METHODS: This retrospective cohort study was conducted in a large tertiary multispecialty academic medical center. Adult patients who underwent noncardiac surgery between January 2005 and July 2016 under general anesthesia with endotracheal intubation and mechanical ventilation were included. A total of 41,224 patients were included in the study.The relationship between mean intraoperative VT per PBW and AKI was assessed using logistic regression, adjusting for prespecified potential confounding variables. The secondary outcomes were postoperative major pulmonary complications, myocardial injury after noncardiac surgery (MINS), and in-hospital mortality. RESULTS: The incidence of AKI was 10.9% in the study population. Postoperative renal replacement therapy was required in 0.1% of patients. Higher delivered mean intraoperative VT per PBW was significantly associated with increased odds of AKI. The estimated odds ratio for each 1 mL increase in VT per kilogram of PBW (1 unit) was 1.05 (95% confidence interval [CI], 1.02-1.08; P = .001), after adjusting for potential confounding variables. A higher delivered mean intraoperative VT per PBW was significantly associated with increased odds of postoperative myocardial injury and was not significantly associated with major postoperative pulmonary complications or in-hospital mortality after noncardiac surgery. CONCLUSIONS: In adult patients undergoing noncardiac surgery, higher delivered mean intraoperative VTs per PBW are associated with an increased odds of developing AKI.

Association of Testosterone Replacement Therapy and the Incidence of a Composite of Postoperative In-Hospital Mortality and Cardiovascular Events in Men Undergoing Cardiac Surgery.

BACKGROUND: Data on testosterone replacement therapy and cardiovascular outcomes are conflicting, with the Food and Drug Administration requiring prescription testosterone preparations to indicate a possible increased cardiovascular risk. Whether patients on testosterone replacement therapy undergoing cardiac surgery have an increased risk of postoperative in-hospital mortality and cardiovascular events remains unknown. We therefore sought to identify the impact of testosterone replacement on the incidence of a composite of postoperative in-hospital mortality and cardiovascular events in men undergoing cardiac surgery. METHODS: After institutional review board approval, data from male American Society of Anesthesiologists III/IV patients ≥40 years of age who underwent cardiac surgery between May 2005 and March 2017 at the Cleveland Clinic (Cleveland, OH) main campus were included. The primary exposure was preoperative testosterone use. The primary outcome was a collapsed composite of postoperative in-hospital mortality and cardiovascular events, including myocardial infarction, stroke, and pulmonary embolism. The secondary outcome was a collapsed composite of minor cardiovascular events, including postoperative rhythm disturbance requiring permanent device, atrial fibrillation, and deep venous thrombosis. We compared patients who received testosterone and those who did not, using propensity score matching within surgical procedure matches. Moreover, as a sensitivity analysis, we used a multivariable logistic regression model to assess the association between testosterone replacement therapy and major or minor cardiovascular events adjusted for potential baseline and intraoperative confounders by including all eligible patients. RESULTS: Among 20,604 patients who met inclusion and exclusion criteria, 301 patients who used testosterone routinely within 1 month before the surgery were matched to 1505 of 20,303 patients who did not use testosterone. Among the matched cohort, 8 (2.7%) patients in the testosterone group and 45 (3.0%) in the nontestosterone group had ≥1 major cardiovascular adverse event after surgery. The adjusted odds ratio was 0.89 (95% CI, 0.41-1.90; P = .756), comparing testosterone to nontestosterone patients. As for the secondary outcomes, 89 (30%) patients in the testosterone group and 525 (35%) patients in the nontestosterone group had ≥1 minor cardiovascular event. The odds of minor events were not significantly different, with an odds ratio of 0.78 (95% CI, 0.60-1.02; P = .074) comparing testosterone to nontestosterone patients. CONCLUSIONS: Preoperative testosterone is not associated with a statistically significant increased incidence of a composite of postoperative in-hospital mortality and cardiovascular events after cardiac surgery.

Vasopressor Infusion During Prone Spine Surgery and Acute Renal Injury: A Retrospective Cohort Analysis.

BACKGROUND: Hypotension is associated with acute kidney injury, but vasopressors used to treat hypotension may also compromise renal function. We therefore tested the hypothesis that vasopressor infusion during complex spine surgery is not associated with impaired renal function. METHODS: In this retrospective cohort analysis, we considered adults who had complex spine surgery between January 2005 and September 2014 at the Cleveland Clinic Main Campus. Our primary outcome was postoperative estimated glomerular filtration rate. Secondarily, we evaluated renal function using Acute Kidney Injury Network criteria. We obtained data for 1814 surgeries, including 689 patients (38%) who were given intraoperative vasopressors infusion for ≥30 minutes and 1125 patients (62%) who were not. Five hundred forty patients with and 540 patients without vasopressor infusions were well matched across 32 potential confounding variables. RESULTS: In matched patients, vasopressor infusions lasted an average of 173 ± 100 minutes (SD) and were given a median dose (1st quintile, 3rd quintile) of 3.4-mg (1.5, 6.7 mg) phenylephrine equivalents. Mean arterial pressure and the amounts of hypotension were similar in each matched group. The postoperative difference in mean estimated glomerular filtration rate in patients with and without vasopressor infusions was only 0.8 mL/min/1.73 m (95% CI, -0.6 to 2.2 mL/min/1.73 m) (P = .28). Intraoperative vasopressor infusion was also not associated with increased odds of augmented acute kidney injury stage. CONCLUSIONS: Clinicians should not avoid typical perioperative doses of vasopressors for fear of promoting kidney injury. Tolerating hypotension to avoid vasopressor use would probably be a poor strategy.

Simulation Versus Problem Based Learning for Cerebrospinal Drainage Catheter Insertion and Management: A Randomized Trial in a Large Academic Anesthesiology Residency Program.

OBJECTIVE: Cerebrospinal fluid drainage catheter-related complications can be reduced by following strict guidelines during their introduction, maintenance, and removal. The authors therefore aimed to determine whether simulation-based learning would improve senior anesthesiology residents' patient care performance during the insertion and management of these catheters compared to interactive problem-based learning (PBL) using the Anaesthetists' Non-Technical Skills global rating scale (ANTS). DESIGN: Prospective randomized trial. SETTING: Vascular or hybrid operating rooms in a large academic tertiary care center. PARTICIPANTS: Senior anesthesia (categorical anesthesia-3) residents rotating through the vascular rotation at the Cleveland Clinic main campus in the period between December 2014 and June 2017. INTERVENTION: Simulation-based learning versus PBL. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the composite score (ANTS global rating scale) achieved by participating residents as evaluated by their supervising anesthesiologists. Out of 28 residents who completed the study, N = 13 were randomized to simulation-based learning and N = 15 residents to the PBL approach. The median (first quartile, third quartile) composite score was 16 (14, 16) and 16 (13, 16) for the simulation-based learning and PBL groups, respectively. There was no significant difference in staff evaluation of the 2 study groups (p = 0.48) with an estimated odds (95% confidence interval) of getting a better staff evaluation score of 1.9 (0.3-10.6) times higher comparing simulation versus traditional training groups. CONCLUSION: Compared to interactive PBL, simulation-based learning does not result in a statistically significant improvement in anesthesia resident performance during insertion and management of cerebrospinal fluid drainage catheters.

A Randomized Trial of Continuous Noninvasive Blood Pressure Monitoring During Noncardiac Surgery.

BACKGROUND: Intraoperative hypotension is associated with postoperative mortality. Early detection of hypotension by continuous hemodynamic monitoring might prompt timely therapy, thereby reducing intraoperative hypotension. We tested the hypothesis that continuous noninvasive blood pressure monitoring reduces intraoperative hypotension. METHODS: Patients ≥45 years old with American Society of Anesthesiologists physical status III or IV having moderate-to-high-risk noncardiac surgery with general anesthesia were included. All participating patients had continuous noninvasive hemodynamic monitoring using a finger cuff (ClearSight, Edwards Lifesciences, Irvine, CA) and a standard oscillometric cuff. In half the patients, randomly assigned, clinicians were blinded to the continuous values, whereas the others (unblinded) had access to continuous blood pressure readings. Continuous pressures in both groups were used for analysis. Time-weighted average for mean arterial pressure <65 mm Hg was compared using 2-sample Wilcoxon rank-sum tests and Hodges Lehmann estimation of location shift with corresponding asymptotic 95% CI. RESULTS: Among 320 randomized patients, 316 were included in the intention-to-treat analysis. With 158 patients in each group, those assigned to continuous blood pressure monitoring had significantly lower time-weighted average mean arterial pressure <65 mm Hg, 0.05 [0.00, 0.22] mm Hg, versus intermittent blood pressure monitoring, 0.11 [0.00, 0.54] mm Hg (P = .039, significance criteria P < .048). CONCLUSIONS: Continuous noninvasive hemodynamic monitoring nearly halved the amount of intraoperative hypotension. Hypotension reduction with continuous monitoring, while statistically significant, is currently of uncertain clinical importance.

Association of Testosterone Replacement Therapy and the Incidence of a Composite of Postoperative In-hospital Mortality and Cardiovascular Events in Men Undergoing Noncardiac Surgery.

BACKGROUND: Whether patients on testosterone replacement therapy undergoing noncardiac surgery have an increased risk of postoperative in-hospital mortality and cardiovascular events remains unknown. We therefore sought to identify the impact of testosterone replacement on the incidence of a composite of postoperative in-hospital mortality and cardiovascular events in men undergoing noncardiac surgery. METHODS: Data from male American Society of Anesthesiologists I through IV patients 40 yr or older who underwent noncardiac surgery between May 2005 and December 2015 at the Cleveland Clinic (Cleveland, Ohio) main campus were included. The primary exposure was preoperative testosterone use. The primary outcome was a composite of postoperative in-hospital mortality and cardiovascular events. We compared patients who received testosterone and those who did not using propensity score matching within surgical procedure matches. RESULTS: Among 49,273 patients who met inclusion and exclusion criteria, 947 patients on testosterone were matched to 4,598 nontestosterone patients. The incidence of in-hospital mortality was 1.3% in the testosterone group and 1.1% in the nontestosterone group, giving an odds ratio of 1.17 (99% CI, 0.51 to 2.68; P = 0.63). The incidence of myocardial infarction was 0.2% in the testosterone group and 0.6% in the nontestosterone group (odds ratio = 0.34; 99% CI, 0.05 to 2.28; P = 0.15). Similarly, no significant difference was found in stroke (testosterone vs. nontestosterone: 2.0% vs. 2.1%), pulmonary embolism (0.5% vs. 0.7%), or deep venous thrombosis (2.0% vs. 1.7%). CONCLUSIONS: Preoperative testosterone is not associated with an increased incidence of a composite of postoperative in-hospital mortality and cardiovascular events.

Attempted Development of a Tool to Predict Anesthesia Preparation Time From Patient-Related and Procedure-Related Characteristics.

BACKGROUND: Operating room (OR) utilization generally ranges from 50% to 75%. Inefficiencies can arise from various factors, including prolonged anesthesia preparation time, defined as the period from induction of anesthesia until patients are considered ready for surgery. Our goal was to use patient-related and procedure-related factors to develop a model predicting anesthesia preparation time. METHODS: From the electronic medical records of adults who had noncardiac surgery at the Cleveland Clinic Main Campus, we developed a model that used a dozen preoperative factors to predict anesthesia preparation time. The model was based on multivariable regression with "Least Absolute Shrinkage and Selection Operator" and 10-fold cross-validation. The overall performance of the final model was measured by R, which describes the proportion of the variance in anesthesia preparation time that is explained by the model. RESULTS: A total of 43,941 cases met inclusion and exclusion criteria. Our final model had only moderate discriminative ability. The estimated adjusted R for prediction model was 0.34 for the training data set and 0.27 for the testing data set. CONCLUSIONS: Using preoperative factors, we could explain only about a quarter of the variance in anesthesia preparation time-an amount that is probably of limited clinical value.

The relative effects of dexmedetomidine and propofol on cerebral blood flow velocity and regional brain oxygenation: A randomised noninferiority trial.

BACKGROUND: Dexmedetomidine constricts cerebral blood vessels without a concomitant reduction in cerebral metabolic oxygen consumption. Its safety as a sedative in patients with neurological diseases thus remains uncertain. OBJECTIVE: Our primary objective was to test the hypothesis that dexmedetomidine is noninferior to propofol as regards cerebral blood flow (CBF) velocity and brain oxygenation. DESIGN: Unblinded randomised trial. SETTING: Cleveland Clinic Hospital, Cleveland, from November 2010 to July 2013. PATIENTS: Forty-four patients scheduled for insertion of a deep-brain stimulating electrodes. INTERVENTIONS: Patients were randomised to receive either dexmedetomidine or propofol sedation during deep-brain stimulating electrode insertion. MAIN OUTCOME MEASURES: Intraoperative CBF velocity was measured with transcranial Doppler, and brain oxygenation was assessed with near-infrared spectroscopy. Noninferiority of dexmedetomidine to propofol was defined as a less than 20% difference in means. RESULTS: Twenty-three patients were given dexmedetomidine and 21 propofol. Baseline characteristics and operative management were similar in each group. Dexmedetomidine was noninferior to propofol on both CBF and brain oxygenation, confirming our primary hypothesis. For cerebral flood flow, the estimated ratio of means (dexmedetomidine/propofol) was 0.94 [90% CI: 0.84 to 1.05], P = 0.011 for noninferiority. For brain oxygenation, the estimated ratio of means was 0.99 [90% CI: 0.96 to 1.02], P < 0.001 for noninferiority. Superiority was not found for either primary outcome. Dexmedetomidine provided deeper sedation than propofol, with a difference of medians of 1 [90% CI: 0 to 2], P < 0.001 on the Observer's Assessment of Alertness/Sedation scale. No significant differences were observed in pulsatility index, cerebral perfusion pressure, number of hypertensive or apnoeic episodes. CONCLUSION: Regional brain oxygenation and CBF velocity are comparably preserved during dexmedetomidine and propofol sedation. Thus, the use of dexmedetomidine in patients with movement disorders appears reasonable. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov (NCT 01200433).

Anesthetic management in patients having catheter-based thrombectomy for acute pulmonary embolism: A narrative review.

Pulmonary embolism is the third leading cause of cardiovascular death. Novel percutaneous catheter-based thrombectomy techniques are rapidly becoming popular in high-risk pulmonary embolism - especially in the presence of contraindications to thrombolysis. The interventional nature of these procedures and the risk of sudden cardiorespiratory compromise requires the presence of an anesthesiologist. Facilitating catheter-based thrombectomy can be challenging since qualifying patients are often critically ill. The purpose of this narrative review is to provide guidance to anesthesiologists for the assessment and management of patients having catheter-based thrombectomy for acute pulmonary embolism. First, available techniques for catheter-based thrombectomy are reviewed. Then, we discuss definitions and application of common risk stratification tools for pulmonary embolism, and how to assess patients prior to the procedure. An adjudication of risks and benefits of anesthetic strategies for catheter-based thrombectomy follows. Specifically, we give guidance and rationale for use monitored anesthesia care and general anesthesia for these procedures. For both, we review strategies for assessing and mitigating hemodynamic perturbations and right ventricular dysfunction, ranging from basic monitoring to advanced inodilator therapy. Finally, considerations for management of right ventricular failure with mechanical circulatory support are discussed.

Transfusion of older red blood cells is associated with decreased graft survival after orthotopic liver transplantation.

Investigations have demonstrated conflicting results regarding the influence of the red blood cell (RBC) storage duration on outcomes. We evaluated whether graft failure or mortality after orthotopic liver transplantation (OLT) increased when recipients were transfused with older RBCs. This study included 637 patients who underwent OLT between January 2001 and June 2011. Baseline and perioperative data were obtained from our blood bank, the Unified Transplant Center database, and the United Network for Organ Sharing database. Recipients whose transfused RBCs were all stored for ≤ 15 days were grouped in a younger group, and recipients who were transfused with RBCs stored for >15 days were placed in an older group. The relationship between graft survival/mortality and the age of intraoperatively transfused RBCs was studied by Kaplan-Meier estimation with a log-rank test and multivariate Cox proportional hazards regression. Three hundred thirty-four patients and 303 patients were grouped in the younger and the older RBC groups, respectively, on the basis of the ages of intraoperatively transfused RBCs. Kaplan-Meier estimates of graft survival/mortality as a function of the posttransplant time were significantly different: the older group experienced the outcome sooner than the younger group [P = 0.02 (log-rank test)]. After covariate adjustments, the risk of graft failure/mortality was significantly different at any given time after transplantation between patients receiving intraoperative transfusions of older RBC units and patients receiving intraoperative transfusions of younger RBC units (hazard ratio = 1.65, 95% confidence interval = 1.18-2.31). In conclusion, patients who received intraoperative transfusions of RBCs with longer storage times had an increased risk of adverse outcomes.