CACS, CCTA and mCAD-LT score in the pre-transplant assessment of coronary artery disease and the prediction of post-transplant cardiovascular events.

BACKGROUND: The optimal cardiovascular assessment of liver transplant (LT) candidates is unclear. We aimed to evaluate the performance of CT-based coronary tests (coronary artery calcium score [CACS] and coronary CT angiography [CCTA]) and a modification of the CAD-LT score (mCAD-LT, excluding family history of CAD) to diagnose significant coronary artery disease (CAD) before LT and predict the incidence of post-LT cardiovascular events (CVE). METHODS: We retrospectively analysed a single-centre cohort of LT candidates who underwent non-invasive tests; invasive coronary angiography (ICA) was performed depending on the results of non-invasive tests. mCAD-LT was calculated in all patients. RESULTS: Six-hundred-and-thirty-four LT candidates were assessed and 351 of them underwent LT. CACS, CCTA and ICA were performed in 245, 123 and 120 LT candidates, respectively. Significant CAD was found in 30% of patients undergoing ICA. The AUROCs of mCAD-LT (.722) and CCTA (.654) were significantly higher than that of CACS (.502) to predict the presence of significant CAD. Specificity of the tests ranged between 31% for CCTA and 53% for CACS. Among patients who underwent LT, CACS ≥ 400 and mCAD-LT were independently associated with the incidence of CVE; in patients who underwent CCTA before LT, significant CAD at CCTA also predicted post-LT CVE. CONCLUSION: In this cohort, mCAD-LT score and CT-based tests detect the presence of significant CAD in LT candidates, although they tend to overestimate it. Both mCAD-LT score and CT-based tests classify LT recipients according to their risk of post-LT CVE and can be used to improve post-LT risk mitigation.

Aggressive intraoperative warming versus routine thermal management during non-cardiac surgery (PROTECT): a multicentre, parallel group, superiority trial.

BACKGROUND: Moderate intraoperative hypothermia promotes myocardial injury, surgical site infections, and blood loss. Whether aggressive warming to a truly normothermic temperature near 37°C improves outcomes remains unknown. We aimed to test the hypothesis that aggressive intraoperative warming reduces major perioperative complications. METHODS: In this multicentre, parallel group, superiority trial, patients at 12 sites in China and at the Cleveland Clinic in the USA were randomly assigned (1:1) to receive either aggressive warming to a target core temperature of 37°C (aggressively warmed group) or routine thermal management to a target of 35·5°C (routine thermal management group) during non-cardiac surgery. Randomisation was stratified by site, with computer-generated, randomly sized blocks. Eligible patients (aged ≥45 years) had at least one cardiovascular risk factor, were scheduled for inpatient non-cardiac surgery expected to last 2-6 h with general anaesthesia, and were expected to have at least half of the anterior skin surface available for warming. Patients requiring dialysis and those with a body-mass index exceeding 30 kg/m2 were excluded. The primary outcome was a composite of myocardial injury (troponin elevation, apparently of ischaemic origin), non-fatal cardiac arrest, and all-cause mortality within 30 days of surgery, as assessed in the modified intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT03111875. FINDINGS: Between March 27, 2017, and March 16, 2021, 5056 participants were enrolled, of whom 5013 were included in the intention-to-treat population (2507 in the aggressively warmed group and 2506 in the routine thermal management group). Patients assigned to aggressive warming had a mean final intraoperative core temperature of 37·1°C (SD 0·3) whereas the routine thermal management group averaged 35·6°C (SD 0·3). At least one of the primary outcome components (myocardial injury after non-cardiac surgery, cardiac arrest, or mortality) occurred in 246 (9·9%) of 2497 patients in the aggressively warmed group and in 239 (9·6%) of 2490 patients in the routine thermal management group. The common effect relative risk of aggressive versus routine thermal management was an estimated 1·04 (95% CI 0·87-1·24, p=0·69). There were 39 adverse events in patients assigned to aggressive warming (17 of which were serious) and 54 in those assigned to routine thermal management (30 of which were serious). One serious adverse event, in an aggressively warmed patient, was deemed to be possibly related to thermal management. INTERPRETATION: The incidence of a 30-day composite of major cardiovascular outcomes did not differ significantly in patients randomised to 35·5°C and to 37°C. At least over a 1·5°C range from very mild hypothermia to full normothermia, there was no evidence that any substantive outcome varied. Keeping core temperature at least 35·5°C in surgical patients appears sufficient. FUNDING: 3M and the Health and Medical Research Fund, Food and Health Bureau, Hong Kong. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

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.

Preoperative triage to detect SARS-CoV-2 infection in surgical patients: lessons learned for resuming surgery.

PURPOSE: To define the impact of the COVID-19 outbreak on hospital surgical activity and assess the incidence of perioperative COVID-19 within two protocolized screening pathways for elective and non-elective surgery. METHODS: We conducted a prospective cohort study of adults undergoing surgery during the COVID-19 outbreak. The elective pathway included telephone surveys and a quantitative polymerase-chain-reaction test (RT-PCR) only for patients who were asymptomatic and at low risk of infection. Only patients with negative screening underwent surgery. In the non-elective pathway, preoperative screening was performed during the hospital admission. RESULTS: Among 835 patients considered for the elective pathway, 725 had negative RT-PCR results and underwent surgery. This reflects an 83% reduction in surgical activity from 2019. Moreover, 596 patients underwent non-elective surgery, representing a 28% reduction. Preoperatively, 39 patients (6.5%) tested positive for SARS-CoV-2 and underwent surgery through the non-elective pathway, vs. none in the elective pathway (p < 0.001). Postoperatively, 1.4% of elective surgery patients and 2.2% of non-elective surgery patients tested positive (p > 0.05). Mortality was higher in non-elective surgery (0.6% vs. 2.9%, p < 0.001) and in patients with COVID-19 (0% vs. 14%, p < 0.001). CONCLUSIONS: The low incidence of COVID-19 in elective surgeries during the outbreak demonstrates the importance and effectiveness of preoperative screening, combining surveys and RT-PCR.

Relative contributions of anaemia and hypotension to myocardial infarction and renal injury: Post hoc analysis of the POISE-2 trial.

BACKGROUND: Hypotension and postoperative anaemia are associated with myocardial and renal injury after noncardiac surgery, but the interaction between them remains unknown. OBJECTIVES: To test the hypothesis that a double-hit of postoperative anaemia and hypotension synergistically worsens a 30-day composite of myocardial infarction (MI) and mortality and acute kidney injury (AKI). Characterising the interaction when hypotension and anaemia occur at same time on myocardial infarction and acute kidney injury. DESIGN: Post hoc analysis of the POISE-2 trial. SETTING: Patients were enrolled between July 2010 and December 2013 at 135 hospitals in 23 countries. PATIENTS: Adults at least 45 years old with known or suspected cardiovascular disease. We excluded patients without available postoperative haemoglobin measurements or hypotension duration records. Exposures were the lowest haemoglobin concentration and the average daily duration of SBP less than 90 mmHg within the first four postoperative days. MAIN OUTCOME MEASURES: The primary outcome was a collapsed composite of nonfatal MI and all-cause mortality during the initial 30 postoperative days; our secondary outcome was AKI. RESULTS: We included 7940 patients. The mean ±â€ŠSD lowest postoperative haemoglobin was 10 ±â€Š2 g dl -1 , and 24% of the patients had SBP less than 90 mmHg with daily duration ranging from 0 to 15 h. Four hundred and nine (5.2%) patients had an infarction or died within 30 postoperative days, and 417 (6.4%) patients developed AKI. Lowest haemoglobin concentrations less than 11 g dl -1 , and duration of SBP less than 90 mmHg was associated with greater hazard of composite outcome of nonfatal MI and all-cause mortality, as well as with AKI. However, we did not find significant multiplicative interactions between haemoglobin splines and hypotension duration on the primary composite or on AKI. CONCLUSION: Postoperative anaemia and hypotension were meaningfully associated with both our primary composite and AKI. However, lack of significant interaction suggests that the effects of hypotension and anaemia are additive rather than multiplicative. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01082874.

Pain and Opioid Consumption and Mobilization after Surgery: Post Hoc Analysis of Two Randomized Trials.

BACKGROUND: Early mobilization is incorporated into many enhanced recovery pathways. Inadequate analgesia or excessive opioids may restrict postoperative mobilization. The authors tested the hypotheses that in adults recovering from abdominal surgery, postoperative pain and opioid consumption are inversely related to postoperative mobilization, and that postoperative mobilization is associated with fewer potentially related complications. METHODS: The authors conducted a subanalysis of two trials that enrolled adults recovering from abdominal surgery. Posture and movement were continuously monitored for 48 postoperative hours using noninvasive untethered monitors. Mobilization was defined as the fraction of monitored time spent sitting or standing. RESULTS: A total of 673 patients spent a median [interquartile range] of 7% [3 to 13%] of monitored time sitting or standing. Mobilization time was 1.9 [1.0 to 3.6] h/day for patients with average pain scores 3 or lower, but only 1.2 [0.5 to 2.6] h/day in those with average scores 6 or greater. Each unit increase in average pain score was associated with a decrease in mobilization time of 0.12 (97.5% CI, 0.02 to 0.24; P = 0.009) h/day. In contrast, there was no association between postoperative opioid consumption and mobilization time. The incidence of the composite of postoperative complications was 6.0% (10 of 168) in the lower mobilization quartile, 4.2% (7 of 168) in the second quartile, and 0% among 337 patients in the highest two quartiles (P = 0.009). CONCLUSIONS: Patients recovering from abdominal surgery spent only 7% of their time mobilized, which is considerably less than recommended. Lower pain scores are associated with increased mobility, independently of opioid consumption. Complications were more common in patients who mobilized poorly.

Tidal Volume and Positive End-expiratory Pressure and Postoperative Hypoxemia during General Anesthesia: A Single-center Multiple Crossover Factorial Cluster Trial.

BACKGROUND: Intraoperative mechanical ventilation is a major component of general anesthesia. The extent to which various intraoperative tidal volumes and positive end-expiratory pressures (PEEP) effect on postoperative hypoxia and lung injury remains unclear. We hypothesized that adults having orthopedic surgery, ventilation using different tidal volumes and PEEP levels affect the oxygenation within first hour in the postoperative care unit. METHODS: We conducted a two-by-two factorial crossover cluster trial at the Cleveland Clinic Main Campus. We enrolled patients having orthopedic surgery with general anesthesia who were assigned to factorial clusters with tidal volumes of 6 or 10 ml/kg of predicted body weight and to PEEP of 5 or 8 cm H2O in 1-week clusters. The primary outcome was the effect of tidal volume or PEEP on time-weighted average peripheral oxygen saturation measured by pulse oximetry divided by the fraction of inspired oxygen (Spo2/Fio2 ratio) during the initial postoperative hour. RESULTS: We enrolled 2,860 patients who had general anesthesia for orthopedic surgery from September 2018 through October 2020. The interaction between tidal volume and PEEP was not significant (P = 0.565). The mean ± SD time-weighted average of Spo2/Fio2 ratio was 353 ± 47 and not different in patients assigned to high and low tidal volume (estimated effect, 3.5%; 97.5% CI, -0.4% to 7.3%; P = 0.042), for those assigned to high and low PEEP (estimated effect, -0.2%; 97.5% CI, -4.0% to 3.6%; P = 0.906). We did not find significant difference in ward Spo2/Fio2 ratio, pulmonary complications, and duration of hospitalization among patients assigned to various tidal volumes and PEEP levels. CONCLUSIONS: Among adults having major orthopedic surgery, postoperative oxygenation is similar, with tidal volumes between 6 and 10 ml/kg and PEEP between 5 and 8 cm H2O. Our results suggest that any combination of tidal volumes between 6 and 10 ml/kg and PEEP between 5 versus 8 ml cm H2O can be used safely for orthopedic surgery.

Prolonged Blood Storage and Risk of Posttransfusion Acute Kidney Injury.

BACKGROUND: Erythrocyte transfusions are independently associated with acute kidney injury. Kidney injury may be consequent to the progressive hematologic changes that develop during storage. This study therefore tested the hypothesis that prolonged erythrocyte storage increases posttransfusion acute kidney injury. METHODS: The Informing Fresh versus Old Red Cell Management (INFORM) trial randomized 31,497 patients to receive either the freshest or oldest available matching erythrocyte units and showed comparable mortality with both. This a priori substudy compared the incidence of posttransfusion acute kidney injury in the randomized groups. Acute kidney injury was defined by the creatinine component of the Kidney Disease: Improving Global Outcomes criteria. RESULTS: The 14,461 patients included in this substudy received 40,077 erythrocyte units. For patients who received more than one unit, the mean age of the blood units was used as the exposure. The median of the mean age of blood units transfused per patient was 11 days [interquartile range, 8, 15] in the freshest available blood group and 23 days [interquartile range, 17, 30] in the oldest available blood group. In the primary analysis, posttransfusion acute kidney injury was observed in 688 of 4,777 (14.4%) patients given the freshest available blood and 1,487 of 9,684 (15.4%) patients given the oldest available blood, with an estimated relative risk (95% CI) of 0.94 (0.86 to 1.02; P = 0.132). The secondary analysis treated blood age as a continuous variable (defined as duration of storage in days), with an estimated relative risk (95% CI) of 1.00 (0.96 to 1.04; P = 0.978) for a 10-day increase in the mean age of erythrocyte units. CONCLUSIONS: In a population of patients without severely impaired baseline renal function receiving fewer than 10 erythrocyte units, duration of blood storage had no effect on the incidence of posttransfusion acute kidney injury.

Intraoperative Hypotension and Myocardial Injury After Noncardiac Surgery in Adults With or Without Chronic Hypertension: A Retrospective Cohort Analysis.

BACKGROUND: The risk of myocardial injury progressively increases at intraoperative mean arterial pressures (MAPs) ≤65 mm Hg. Higher pressures might be required in chronically hypertensive patients. We aimed to test the hypothesis that the harm threshold is higher in patients with chronic hypertension than in normotensive patients. METHODS: We conducted a single-center retrospective cohort analysis of adults >45 years old who had noncardiac surgery between 2010 and 2018 and scheduled, rather than symptom-driven, postoperative troponin measurements. The MAP thresholds under which risk started to increase were compared between patients with chronic hypertension (baseline MAP ≥110 mm Hg) and normotensive patients (baseline MAP <110 mm Hg). The primary outcome was a composite of in-hospital mortality and myocardial injury within 30 days, defined by any postoperative 4th-generation troponin T measurement ≥0.03 ng/mL apparently due to cardiac ischemia. Multivariable logistic regression and moving average smoothing methods were used to evaluate confounder-adjusted associations between the composite outcome and the lowest intraoperative MAP sustained for either 5 or 10 cumulative minutes, and whether the relationship depended on baseline pressure (normotensive versus hypertensive). RESULTS: Among 4576 eligible surgeries, 2066 were assigned to the normotensive group with mean (standard deviation [SD]) baseline MAP of 100 (7) mm Hg, and 2510 were assigned to the hypertensive group with mean baseline MAP of 122 (10) mm Hg. The overall incidence of the composite outcome was 5.6% in normotensive and 6.0% in hypertensive patients ( P = .55). The relationship between intraoperative hypotension and the composite outcome was not found to depend on baseline MAP in a multivariable mixed effects logistic regression model. Furthermore, no statistical change points were found for either baseline MAP group. CONCLUSIONS: Baseline blood pressure of the hypertensive patients was only moderately increased on average, and the event rate was low. Nonetheless, we were not able to demonstrate a difference in the harm threshold between normotensive and chronically hypertensive patients. Our results do not support the theory that hypertensive patients should be kept at higher intraoperative pressures than normotensive patients.

New-Onset Atrial Fibrillation in Patients Undergoing Liver Transplantation: Retrospective Analysis of Risk Factors and Outcomes.

OBJECTIVE: The authors aimed to identify predictors of new-onset postoperative atrial fibrillation (POAF) during the initial 90 days following liver transplantation, and to assess the association between POAF in-hospital and 1-year mortality. DESIGN: A retrospective cohort study. SETTING: At a university hospital between 2005 and 2017. PATIENTS: Adults without a history of preoperative atrial fibrillation who underwent orthotopicliver transplantation. MEASUREMENT AND MAIN RESULTS: The authors assessed the univariate association between new-onset of POAF in the postoperative period and each potential factor through a logistic regression model. Moreover, they explored predictors for POAF through stepwise selection. Finally, the authors assessed the relationship between POAF and in-hospital and 1-year mortality using logistic regression models, and whether the duration of atrial fibrillation was associated with in-hospital and 1-year mortality. Among 857 patients, 89 (10.4%) developed POAF. Using only preoperative variables, pulmonary hypertension, age, Model for End-Stage Liver Disease (MELD) score, and White race were identified as the most important predictors. Model discrimination was 0.75 (95% CI: 0.69-0.80), and incorporating intraoperative variables was 0.77 (95% CI: 0.72-0.82). In-hospital mortality was observed in 7.2% (6/83) of patients with new-onset of POAF, and in 2.8% (22/768) without, with confounder-adjusted odds ratio (OR) 1.00 (97.5% CI: 0.29,3.45; p = 0.996). One-year mortality was 22.4% (20/89) in patients who developed POAF and 8.3% (64/768) in patients who did not, confounder-adjusted OR 2.64 (97.5% CI: 1.35-5.16; p = 0.001). The duration of POAF did not affect long-term postoperative mortality. CONCLUSION: Preoperative, mostly unmodifiable comorbidities are important risk factors for new-onset POAF after liver transplantation. The POAF was not associated with in-hospital mortality, but with increased 1-year mortality. Once developed, the duration of POAF did not affect long-term mortality after a liver transplant.

Intra-operative hypertension and myocardial injury and/or mortality and acute kidney injury after noncardiac surgery: A retrospective cohort analysis.

BACKGROUND: Whether intra-operative hypertension causes postoperative complications remains unclear. OBJECTIVE: We sought to assess whether there is an absolute systolic hypertensive threshold associated with increased odds of a composite of postoperative myocardial injury and mortality, and acute kidney injury. DESIGN: A retrospective cohort analysis using an electronic medical record registry. SETTING: The Cleveland Clinic Main Campus, Cleveland, Ohio, USA, between January 2005 and December 2018. PATIENTS: A total of 76 042 adults who had inpatient noncardiac surgery lasting at least an hour, creatinine recorded preoperatively and postoperatively, and had an available clinic blood pressure within 6 months before surgery. MAIN OUTCOME MEASURES: Univariable smoothing and multivariable logistic regression were used to estimate the probability of each outcome as a function of the highest intra-operative pressure for a cumulative 5, 10, or 30 min. We further assessed whether the relationships between intra-operative hypertension and each outcome depended on baseline systolic blood pressure. RESULTS: The composite of myocardial injury and mortality was observed in 1.9%, and acute kidney injury in 4.5% of patients. After adjustment for confounders, there was little or no relationship between systolic pressure and either outcome over the range from 120 to 200 mmHg. There were also no obvious change points or thresholds above which odds of each outcome increased. And finally, there was no interaction with preoperative clinic blood pressure. CONCLUSIONS: There was no clinically meaningful relationship between intra-operative systolic pressure and the composite of myocardial injury and mortality, or acute kidney injury, over the range from 120 and 200 mmHg.

Failure to detect ward hypoxaemia and hypotension: contributions of insufficient assessment frequency and patient arousal during nursing assessments.

BACKGROUND: Postoperative hypotension and hypoxaemia are common and often unrecognised. With intermittent nursing vital signs, hypotensive or hypoxaemic episodes might be missed because they occur between scheduled measurements, or because the process of taking vital signs arouses patients and temporarily improves arterial blood pressure and ventilation. We therefore estimated the fraction of desaturation and hypotension episodes that did not overlap nursing assessments and would therefore usually be missed. We also evaluated the effect of taking vital signs on blood pressure and oxygen saturation. METHODS: We estimated the fraction of desaturated episodes (arterial oxygen saturation <90% for at least 90% of the time within 30 continuous minutes) and hypotensive episodes (MAP <70 mm Hg for 15 continuous minutes) that did not overlap nursing assessments in patients recovering from noncardiac surgery. We also evaluated changes over time before and after nursing visits. RESULTS: Among 782 patients, we identified 878 hypotensive episodes and 2893 desaturation episodes, of which 79% of the hypotensive episodes and 82% of the desaturation episodes did not occur within 10 min of a nursing assessment and would therefore usually be missed. Mean BP and oxygen saturation did not improve by clinically meaningful amounts during nursing vital sign assessments. CONCLUSIONS: Hypotensive and desaturation episodes are mostly missed because vital sign assessments on surgical wards are sparse, rather than being falsely negative because the assessment process itself increases blood pressure and oxygen saturation. Continuous vital sign monitoring will detect more disturbances, potentially giving clinicians time to intervene before critical events occur.

Association between postoperative haemoglobin concentrations and composite of non-fatal myocardial infarction and all-cause mortality in noncardiac surgical patients: post hoc analysis of the POISE-2 trial.

BACKGROUND: Myocardial infarction is the most common postoperative major vascular complication. Perioperative anaemia may contribute to cardiac supply-demand mismatch, and therefore myocardial injury. We therefore tested the hypothesis that the lowest in-hospital postoperative haemoglobin concentration is associated with a composite of non-fatal myocardial infarction and all-cause mortality within the first 30 days after noncardiac surgery. METHODS: We conducted a retrospective analysis of patients enrolled in the PeriOperative Ischemic Evaluation-2 (POISE-2) trial. We assessed the association between the lowest postoperative haemoglobin concentration during the initial hospitalisation and a composite of non-fatal myocardial infarction (Third Universal Definition) and all-cause mortality within 30 postoperative days, using a multivariable logistic regression model. RESULTS: We analysed 7227 patients from POISE-2, of whom 7.8% developed myocardial infarction; 1.5% died within 30 days. The composite primary outcome of non-fatal myocardial infarction and all-cause mortality occurred in 8.9% patients overall, ranging from 16% in patients with postoperative haemoglobin concentrations <88 g L-1 to 4.1% in patients with postoperative haemoglobin >113 g L-1. After adjusting for baseline factors, in patients with a lowest postoperative haemoglobin concentration <110 g L-1, each 10 g L-1 reduction in the lowest postoperative haemoglobin concentration was associated with a 1.46 (95% confidence interval: 1.37-1.56; P<0.001) fold increase in the odds of the composite outcome. In contrast, there was no significant relationship amongst patients with lowest postoperative haemoglobin concentration >110 g L-1. CONCLUSIONS: Postoperative anaemia may be a modifiable risk factor for non-fatal myocardial infarction and all-cause mortality.

Association between postoperative haemoglobin and myocardial injury after noncardiac surgery: a retrospective cohort analysis.

BACKGROUND: Myocardial injury after noncardiac surgery (MINS) is common, mostly silent, and a strong predictor of postoperative mortality. MINS appears to result from myocardial supply-demand mismatch. Recent data support restrictive perioperative transfusion strategies that can result in low postoperative haemoglobin concentrations. Whether low postoperative haemoglobin is associated with myocardial injury remains unknown. We therefore tested the hypothesis that anaemia is associated with an increased risk of myocardial injury in adults having noncardiac surgery. METHODS: We conducted a retrospective analysis of adults ≥45 yr old who had routine postoperative troponin T (TnT) monitoring after noncardiac surgery at the Cleverland Clinic (including those enrolled in the PeriOperative ISchemic Evaluation-2 Trial [POISE-2], the Safety of Addition of Nitrous Oxide to General Anaesthesia in At-risk Patients Having Major Non-cardiac Surgery [ENIGMA-II], Vascular Events In Noncardiac Surgery Patients Cohort Evaluation Study [VISION], and Anaesthetic Depth and Complications After Major Surgery [BALANCED] trial). Patients with baseline increase in TnT and non-ischaemic aetiologies for TnT increase were excluded. The association between postoperative haemoglobin concentration during the 3 initial postoperative days and the incidence of MINS (fourth-generation TnT ≥0.03 ng ml-1 judged as attributable to ischaemia) was assessed using a time-varying covariate Cox proportional hazards survival analysis. RESULTS: Among 6141 patients, 4480 were analysed. The incidence of MINS was 155/4480 (3.5%), ranging from 0/345 (0%) among patients whose lowest postoperative haemoglobin exceeded 13 g dl-1 to 52/611 (8.5%) in patients whose minimum postoperative haemoglobin was <8 g dl-1. The confounder-adjusted hazard ratio [95% confidence interval] for having MINS was 1.29 [1.16-1.42] for every 1 g dl-1 decrease in postoperative haemoglobin in a time-varying covariate analysis. Similar associations were identified in sensitivity analyses. CONCLUSION: Lower postoperative haemoglobin values are associated with MINS. Whether this association is modifiable by prevention or treatment of anaemia remains to be determined.

Effect of Intravenous Acetaminophen on Mean Arterial Blood Pressure: A Post Hoc Analysis of the EFfect of Intravenous ACetaminophen on PosToperative HypOxemia After Abdominal SurgeRy Trial.

BACKGROUND: Acetaminophen is commonly used as part of multimodal analgesia for acute pain. The intravenous formulation offers a more predictable bioavailability compared to oral and rectal acetaminophen. There have been reports of hypotension with intravenous acetaminophen attributable to centrally mediated and vasodilatory effects. We tested the hypothesis that in adults having abdominal surgery the use of intravenous acetaminophen versus placebo for postoperative pain management is associated with a decrease in mean arterial pressure (MAP) after its administration. METHODS: This is a substudy of eFfect of intravenous ACetaminophen on posToperative hypOxemia after abdominal surgeRy (FACTOR) trial (NCT02156154). FACTOR trial randomly assigned adults undergoing abdominal surgery to either 1 g of acetaminophen or placebo every 6 hours during the first postoperative 48 hours. Continuous monitoring of blood pressure was obtained by noninvasive ViSi Mobile device (Sotera Wireless, Inc, San Diego, CA) at 15-second intervals during initial 48 hours postoperatively. We excluded patients without continuous monitoring data available. The primary outcome was the MAP difference between MAP 5 minutes before study drug administration (baseline) and MAP 30 minutes poststudy drug administration initiation. We used a linear mixed effects model to assess the treatment effect on MAP change. The secondary outcome was MAP area under baseline (AUB) during the 30 minutes after treatment. In a sensitivity analysis of change in MAP from predrug to postdrug administration, we instead used postdrug MAP as the outcome adjusting for the baseline MAP in the model. RESULTS: Among 358 patients analyzed, 182 received acetaminophen and 176 placebo. The mean (standard deviation [SD]) of average MAP change was -0.75 (5.9) mm Hg for the treatment and 0.32 (6.3) mm Hg for the placebo. Acetaminophen was found to decrease the MAP from baseline more than placebo after drug administration. The estimated difference in mean change of MAP was -1.03 (95% confidence interval [CI] -1.60 to -0.47) mm Hg; P < .001. The sensitivity analysis showed postoperative MAP in the acetaminophen group was 1.33 (95% CI, 0.76-1.90) mm Hg lower than in the placebo group (P < .001). The median of MAP AUB was 33 [Q1 = 3.3, Q3 = 109] mm Hg × minutes for the treatment and 23 [1.6, 79] mm Hg × minutes for the placebo. Acetaminophen was found to increase the AUB with an estimated median difference of 15 (95% CI, 5-25) mm Hg × minutes (P = .003). CONCLUSIONS: Intravenous acetaminophen decreases MAP after its administration. However, this decrease does not appear to be clinically meaningful. Clinicians should not refrain to use intravenous acetaminophen for acute pain management because of worries of hypotension.

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.

Effects of an Animated Blood Clot Technology (Visual Clot) on the Decision-Making of Users Inexperienced in Viscoelastic Testing: Multicenter Trial.

BACKGROUND: Viscoelastic test-guided coagulation management has become increasingly important in assessing hemostasis. We developed Visual Clot, an animated, 3D blood clot that illustrates raw rotational thromboelastometry (ROTEM) parameters in a user-centered and situation awareness-oriented method. OBJECTIVE: This study aimed to evaluate the applicability of Visual Clot by examining its effects on users that are novices in viscoelastic-guided resuscitation. METHODS: We conducted an investigator-initiated, international, multicenter study between September 16, 2020, and October 6, 2020, in 5 tertiary care hospitals in central Europe. We randomly recruited medical students and inexperienced resident physicians without significant prior exposure to viscoelastic testing. The 7 participants per center managed 9 different ROTEM outputs twice, once as standard ROTEM tracings and once as the corresponding Visual Clot. We randomly presented the 18 viscoelastic cases and asked the participants for their therapeutic decisions. We assessed the performance, diagnostic confidence, and perceived workload in managing the tasks using mixed statistical models and adjusted for possible confounding factors. RESULTS: Analyzing a total of 630 results, we found that the participants solved more cases correctly (odds ratio [OR] 33.66, 95% CI 21.13-53.64; P<.001), exhibited more diagnostic confidence (OR 206.2, 95% CI 93.5-454.75; P<.001), and perceived less workload (coefficient -41.63; 95% CI -43.91 to -39.36; P<.001) using Visual Clot compared to using standard ROTEM tracings. CONCLUSIONS: This study emphasizes the practical benefit of presenting viscoelastic test results in a user-centered way. Visual Clot may allow inexperienced users to be involved in the decision-making process to treat bleeding-associated coagulopathy. The increased diagnostic confidence, diagnostic certainty, reduced workload, and positive user feedback associated with this visualization may promote the further adoption of viscoelastic methods in diverse health care settings.

McGrath Video Laryngoscope Versus Macintosh Direct Laryngoscopy for Intubation of Morbidly Obese Patients: A Randomized Trial.

BACKGROUND: Two-thirds of the US population is considered obese and about 8% morbidly obese. Obese patients may present a unique challenge to anesthesia clinicians in airway management. Videolaryngoscopes may provide better airway visualization, which theoretically improves intubation success. However, previous work in morbidly obese patients was limited. We therefore tested the primary hypothesis that the use of McGrath video laryngoscope improves visualization of the vocal cords versus Macintosh direct laryngoscopy (Teleflex, Morrisville, NC) in morbidly obese patients. METHODS: We enrolled 130 surgical patients, aged 18-99 years, with a body mass index ≥40 kg/m and American Society of Anaesthesiologists (ASA) physical status I-III. Patients were randomly allocated 1:1-stratified for patient's body mass index ≥50 kg/m-to McGrath video laryngoscope versus direct laryngoscopy with a Macintosh blade. The study groups were compared on glottis visualization, defined as improved Cormack and Lehane classification, with proportional odds logistic regression model. RESULTS: McGrath video laryngoscope provided significantly better glottis visualization than Macintosh direct laryngoscopy with an estimated odds ratio of 4.6 (95% confidence interval [CI], 2.2-9.8; P < .01). We did not observe any evidence that number of intubation attempts and failed intubations increased or decreased. CONCLUSIONS: McGrath video laryngoscope improves glottis visualization versus Macintosh direct laryngoscopy in morbidly obese patients. Large clinical trials are needed to determine whether improved airway visualization with videolaryngoscopy reduces intubation attempts and failures.

Incidence of adverse events attributable to bupivacaine liposome injectable suspension or plain bupivacaine for postoperative pain in pediatric surgical patients: A retrospective matched cohort analysis.

BACKGROUND: Surgical wound infiltration with local anesthetics is common as part of multimodal analgesia and enhanced recovery pathways in pediatric surgical patients. Liposomal bupivacaine can provide up to 92 hours of pain relief, and was approved by the U.S Food and Drug Administration for local infiltration in adults. It is also commonly used by pediatric surgeons, but its safety profile in this age group has not been described. AIMS: The aim of this study was to describe the incidence of local anesthetic systemic toxicity syndrome in pediatric surgical patients receiving liposomal bupivacaine compared to plain bupivacaine for surgical wound infiltration. METHODS: We conducted a retrospective, single center, assessor blinded cohort study of pediatric surgical inpatients having open or laparoscopic surgery in the Cleveland Clinic between 2013 and 2017 and receiving wound infiltration with local anesthetics. We compared the incidence of local anesthetic systemic toxicity among those who received any dose of liposomal bupivacaine and those who received plain bupivacaine. Groups were matched 1:2 according to procedure type, age, and physical status score. Local anesthetic systemic toxicity was primarily defined as at least two signs or symptoms possibly related to anesthetic toxicity, as judged by two independent adjudicators blinded to the type of local anesthetic. A sensitivity analysis compared the incidence of a single sign/symptom possibly related to anesthetic toxicity. RESULTS: A total of 924 surgical cases were included in the final analysis (356 liposomal bupivacaine and 568 plain bupivacaine cases). The primary outcome did not occur in any patient. The sensitivity analysis found three cases in the liposomal bupivacaine group and two cases in the plain bupivacaine group having a single sign/symptom possibly related to local anesthetic administration (relative risk 2.4, 95% CI 0.4-14.0, P = 0.38). CONCLUSION: In a cohort of pediatric surgical patients receiving wound infiltration with either plain or liposomal bupivacaine, we identified no cases of local anesthetic systemic toxicity syndrome, and only few patients with any sign or symptom that could potentially be related to local anesthetic toxicity.

Intra-operative high inspired oxygen fraction does not increase the risk of postoperative respiratory complications: Alternating intervention clinical trial.

BACKGROUND: The WHO recommends routine intra-operative and early postoperative use of high inspired oxygen concentrations (hyperoxia). However, a high intra-operative inspired oxygen fraction (FiO2) might result in an increased risk of postoperative respiratory complications. AIM: To test the hypothesis that intra-operative FiO2 of 80% compared with 30% inspired oxygen decreases the postoperative ratio of arterial saturation to fraction of inspired oxygen (SpO2/FiO2). Secondarily, to evaluate whether an intra-operative inspired FiO2 of 80% increases the incidence of pulmonary complications. DESIGN: Posthoc subanalysis of a large alternating cohort trial. SETTING: Cleveland Clinic, Cleveland, United States, from 2013 to 2016. PATIENTS: Adults having colorectal surgery. Cases lasting less than 2 h, re-operations on the same hospitalisation, and cases with missing intra-operative or postoperative data were excluded. INTERVENTION: Maintaining intra-operative FiO2 at 30 or 80% and alternating this management every 2 weeks for a study period of 39 months. MAIN OUTCOME: Minimal SpO2/FiO2 ratio value in the postanaesthesia care unit. Secondary outcome was a composite of postoperative pulmonary complications throughout hospitalisation. RESULTS: A total of 5056 patients were included. Groups were well balanced on all demographic, baseline and procedural variables. Median time-weighted averages of intra-operative FiO2 in the 30 and 80% groups were 43% (IQR 38 to 54%, N=2486) and 81% (IQR 78 to 82%, N=2570), respectively. No difference was found in the lowest SpO2/FiO2 ratio (estimated median difference 0 [95% confidence interval: 0, 0], P = 0.91). The incidence of postoperative pulmonary complications was 16.3 and 17.6% in the 30 and 80% FiO2 groups, respectively (relative risk 1.07 [95% confidence interval: 0.95, 1.21], P = 0.25). CONCLUSION: Intra-operative hyperoxia did not change the postoperative SpO2/FiO2 ratio or the risk for pulmonary complications. Clinicians should not refrain from using hyperoxia for fear of provoking respiratory complications. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01777568.