A multicenter study of the risk of major bleeding in patients with and without cirrhosis undergoing percutaneous liver procedures.

Percutaneous liver procedures are frequently performed in patients with abnormal coagulation tests. Current guidelines suggest prophylactic transfusion is not mandatory in all patients with liver disease or cirrhosis, depending on the risk of bleeding. This study aims to describe the incidence and risk of major bleeding after percutaneous liver procedure in patients with and without cirrhosis. This retrospective study includes patients who underwent percutaneous liver biopsy and radiofrequency and microwave ablation of liver lesions at 3 centers in Spain. A transfusion protocol was considered for platelet counts <50,000 and/or international normalized ratio >1.5. The primary outcome was major bleeding. A total of 1797 patients were included in the study, with 316 having cirrhosis (18%) and 1481 without cirrhosis (82%). Among the patients with cirrhosis, 80 were classified as Child A, and percutaneous liver biopsy was the most frequent procedure (86%). Fourteen patients (0.8%) experienced major bleeding, with 0.4% occurring in radiofrequency and microwave ablation and 0.8% in percutaneous liver biopsy. Bleeding occurred in 0.6% of patients with cirrhosis compared to 0.8% in those without ( p = ns). No clinical or procedural variables were associated with bleeding. Twenty-five patients (1.4%) had an international normalized ratio >1.5, and 22 patients (1.2%) had a platelet count <50,000. Only 24% (6/25) of patients with an international normalized ratio >1.5 were transfused with fresh frozen plasma, and 72% (16/22) of those with platelet counts <50,000 received platelet transfusion. Patients with cirrhosis were more frequently transfused (5.9% vs. 1.5%). None of the patients who met the criteria for transfusion experienced major bleeding, regardless of whether they received a transfusion, and none of the patients who had a major bleeding episode met the transfusion criteria. In this cohort, major bleeding after percutaneous liver procedure occurred in <1% of patients, making it a low-risk procedure for patients with and without cirrhosis. Although not uniformly adopted, the current transfusion protocol still led to unnecessary blood product administration.

The association of vaping and electronic cigarette use with postoperative hypoxemia and respiratory complications: a retrospective cohort analysis.

PURPOSE: Initially introduced as a safer alternative to smoking, electronic cigarettes (e-cigarettes) and vaping have since been associated with lung injury. Nevertheless, there is limited perioperative data on their potential contribution to the harmful effects of mechanical ventilation on the lungs. We hypothesized that, in adults undergoing noncardiothoracic surgeries, preoperative vaping/e-cigarette use is associated with hypoxemia during the first postoperative hour, and with an increased incidence of intraoperative and postoperative pulmonary complications. METHODS: We conducted a retrospective cohort study in which we included patients reporting as vapers/e-cigarette users within one year before surgery as the exposure group, and nonvapers as the control group. The primary outcome was the time-weighted average (TWA) SpO2/FIO2 ratio in the postanesthesia care unit during the first postoperative hour. The secondary outcome was a composite of intraoperative and postoperative pulmonary complications until discharge. We used entropy balancing to adjust for confounding, and fit weighted linear regression and logistic regression models to estimate treatment effects. RESULTS: A total of 110,940 patients met the inclusion criteria, and 1,941 of these were vapers/e-cigarette users. The average treatment effect on the treated for TWA SpO2/FIO2 ratio (N = 109,217) was estimated to be a mean difference of 4 (95% confidence interval [CI], 1 to 8; P = 0.007). This is equivalent to a 4% change in SpO2 at a 30% FIO2 (or at a fixed FIO2). The difference was statistically significant. The average treatment effect on the treated for experiencing intraoperative and postoperative pulmonary complications (N = 110,940) was an odds ratio of 1.04 (95% CI, 0.71 to 1.54; P = 0.84). CONCLUSION: Vaping/e-cigarette use was neither associated with clinically significant hypoxemia during the first hour in the postanesthesia care unit nor with an increase in pulmonary complications. Nevertheless, our findings cannot definitively exclude the deleterious effects of vaping and e-cigarette use on the lungs, and anesthesiologists should consider potential perioperative complications.

RéSUMé: OBJECTIF: Initialement introduites comme une alternative plus sécuritaire au tabagisme, les cigarettes électroniques et le vapotage ont depuis été associés à des lésions pulmonaires. Néanmoins, il existe peu de données périopératoires concernant leur contribution potentielle aux effets nocifs de la ventilation mécanique sur les poumons. Nous avons émis l'hypothèse que, chez les adultes bénéficiant de chirurgies non cardiothoraciques, l'utilisation préopératoire de vapotage/de cigarette électronique était associée à une hypoxémie au cours de la première heure postopératoire et à une incidence accrue de complications pulmonaires peropératoires et postopératoires. MéTHODE: Nous avons mené une étude de cohorte rétrospective dans laquelle nous avons inclus les patient·es déclarant avoir vapoté ou utilisé des cigarettes électroniques dans l'année précédant la chirurgie comme groupe d'exposition, et les personnes ne vapotant pas comme groupe témoin. Le critère d'évaluation principal était le rapport de SpO2/FIO2 moyen pondéré dans le temps en salle de réveil pendant la première heure postopératoire. Le critère d'évaluation secondaire était un mélange de complications pulmonaires peropératoires et postopératoires jusqu'au congé de l'hôpital. Nous avons utilisé l'équilibrage d'entropie pour ajuster les facteurs de confusion et ajusté les modèles de régression linéaire pondérée et de régression logistique pour estimer les effets du traitement. RéSULTATS: Au total, 110 940 patient·es répondaient aux critères d'inclusion, dont 1941 étaient des vapoteurs ou vapoteuses/utilisaient des cigarettes électroniques. L'effet moyen du traitement sur le rapport de SpO2/FIO2 moyen pondéré dans le temps des personnes traitées (N = 109 217) a été estimé à une différence moyenne de 4 (intervalle de confiance [IC] à 95 %, 1 à 8; P = 0,007). Cela équivaut à une variation de 4 % de la SpO2 à 30% FIO2 (ou à une FIO2 fixe). La différence était statistiquement significative. L'effet moyen du traitement sur les personnes traitées pour des complications pulmonaires peropératoires et postopératoires (N = 110 940) était un rapport de cotes de 1,04 (IC 95 %, 0,71 à 1,54; P = 0,84). CONCLUSION: L'utilisation du vapotage et de la cigarette électronique n'était associée ni à une hypoxémie cliniquement significative au cours de la première heure en salle de réveil, ni à une augmentation des complications pulmonaires. Néanmoins, nos résultats ne peuvent exclure de manière définitive les effets délétères du vapotage et de l'utilisation de la cigarette électronique sur les poumons, et les anesthésiologistes devraient tenir compte des complications périopératoires potentielles.

Association between preoperative anemia optimization and major complications after non-cardiac surgery: a retrospective analysis.

BACKGROUND: Anemia is common in the preoperative setting and associated with increased postoperative complications and mortality. However, it is unclear if preoperative anemia optimization reduces postoperative complications. We aimed to assess the association between preoperative anemia optimization and a composite endpoint of major cardiovascular, renal, and pulmonary complications and all-cause mortality within 30 days after noncardiac surgery in adult patients. METHODS: In this retrospective analysis preoperative anemia was defined as hemoglobin concentration below 12.0 g.dl-1 in women and 13.0 g.dl-1 in men within 6 months before surgery. A propensity score-based generalized estimating equation analysis was used to determine the association between preoperative anemia optimization and the primary outcome. Moreover, mediation analysis was conducted to investigate whether intraoperative red blood cell transfusion or duration of intraoperative hypotension were mediators of the relation between anemia optimization and the primary outcome. RESULTS: Fifty-seven hundred anemia optimized, and 8721 non-optimized patients met study criteria. The proportion of patients having any component of the composite of major complications and all-cause mortality was 21.5% in the anemia-optimized versus 18.0% in the non-optimized, with confounder-adjusted odds ratio estimate of 0.99 (95% CI 0.86‒1.15) for anemia optimization versus non-optimization, p = 0.90. Intraoperative red blood cell transfusion had a minor mediation effect on the relationship between preoperative anemia optimization and the primary outcome, whereas duration of intraoperative hypotension was not found to be a mediator. CONCLUSION: Preoperative anemia optimization did not appear to be associated with a composite outcome of major in-hospital postoperative cardiovascular, renal, and pulmonary complications and all-cause in-hospital mortality.

Association between preoperative anemia optimization and major complications after non-cardiac surgery: a retrospective analysis

Abstract Background: Anemia is common in the preoperative setting and associated with increased postoperative complications and mortality. However, it is unclear if preoperative anemia optimization reduces postoperative complications. We aimed to assess the association between preoperative anemia optimization and a composite endpoint of major cardiovascular, renal, and pulmonary complications and all-cause mortality within 30 days after noncardiac surgery in adult patients. Methods: In this retrospective analysis preoperative anemia was defined as hemoglobin concentration below 12.0 g.dl−1 in women and 13.0 g.dl−1 in men within 6 months before surgery. A propensity score-based generalized estimating equation analysis was used to determine the association between preoperative anemia optimization and the primary outcome. Moreover, mediation analysis was conducted to investigate whether intraoperative red blood cell transfusion or duration of intraoperative hypotension were mediators of the relation between anemia optimization and the primary outcome. Results: Fifty-seven hundred anemia optimized, and 8721 non-optimized patients met study criteria. The proportion of patients having any component of the composite of major complications and all-cause mortality was 21.5% in the anemia-optimized versus 18.0% in the non-optimized, with confounder-adjusted odds ratio estimate of 0.99 (95% CI 0.86-1.15) for anemia optimization versus non-optimization, p = 0.90. Intraoperative red blood cell transfusion had a minor mediation effect on the relationship between preoperative anemia optimization and the primary outcome, whereas duration of intraoperative hypotension was not found to be a mediator. Conclusion: Preoperative anemia optimization did not appear to be associated with a composite outcome of major in-hospital postoperative cardiovascular, renal, and pulmonary complications and all-cause in-hospital mortality.

User Perceptions of Visual Blood: An International Mixed Methods Study on Novel Blood Gas Analysis Visualization.

Blood gas analysis plays a central role in modern medicine. Advances in technology have expanded the range of available parameters and increased the complexity of their interpretation. By applying user-centered design principles, it is possible to reduce the cognitive load associated with interpreting blood gas analysis. In this international, multicenter study, we explored anesthesiologists' perspectives on Visual Blood, a novel visualization technique for presenting blood gas analysis results. We conducted interviews with participants following two computer-based simulation studies, the first utilizing virtual reality (VR) (50 participants) and the second without VR (70 participants). Employing the template approach, we identified key themes in the interview responses and formulated six statements, which were rated using Likert scales from 1 (strongly disagree) to 5 (strongly agree) in an online questionnaire. The most frequently mentioned theme was the positive usability features of Visual Blood. The online survey revealed that participants found Visual Blood to be an intuitive method for interpreting blood gas analysis (median 4, interquartile range (IQR) 4-4, p < 0.001). Participants noted that minimal training was required to effectively learn how to interpret Visual Blood (median 4, IQR 4-4, p < 0.001). However, adjustments are necessary to reduce visual overload (median 4, IQR 2-4, p < 0.001). Overall, Visual Blood received a favorable response. The strengths and weaknesses derived from these data will help optimize future versions of Visual Blood to improve the presentation of blood gas analysis results.

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.

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.

Visual Blood, Visualisation of Blood Gas Analysis in Virtual Reality, Leads to More Correct Diagnoses: A Computer-Based, Multicentre, Simulation Study.

Interpreting blood gas analysis results can be challenging for the clinician, especially in stressful situations under time pressure. To foster fast and correct interpretation of blood gas results, we developed Visual Blood. This computer-based, multicentre, noninferiority study compared Visual Blood and conventional arterial blood gas (ABG) printouts. We presented six scenarios to anaesthesiologists, once with Visual Blood and once with the conventional ABG printout. The primary outcome was ABG parameter perception. The secondary outcomes included correct clinical diagnoses, perceived diagnostic confidence, and perceived workload. To analyse the results, we used mixed models and matched odds ratios. Analysing 300 within-subject cases, we showed noninferiority of Visual Blood compared to ABG printouts concerning the rate of correctly perceived ABG parameters (rate ratio, 0.96; 95% CI, 0.92-1.00; p = 0.06). Additionally, the study revealed two times higher odds of making the correct clinical diagnosis using Visual Blood (OR, 2.16; 95% CI, 1.42-3.29; p < 0.001) than using ABG printouts. There was no or, respectively, weak evidence for a difference in diagnostic confidence (OR, 0.84; 95% CI, 0.58-1.21; p = 0.34) and perceived workload (Coefficient, 2.44; 95% CI, -0.09-4.98; p = 0.06). This study showed that participants did not perceive the ABG parameters better, but using Visual Blood resulted in more correct clinical diagnoses than using conventional ABG printouts. This suggests that Visual Blood allows for a higher level of situation awareness beyond individual parameters' perception. However, the study also highlighted the limitations of today's virtual reality headsets and Visual Blood.

Association between obstructive sleep apnea and atrial fibrillation and delirium after cardiac surgery. Sub-analysis of DECADE trial.

BACKGROUND: Atrial fibrillation and delirium are common complications after cardiac surgery. Both are associated with increased Intensive Care Unit (ICU) and hospital length of stay, functional decline, 30-day mortality and increase in health care costs. Obstructive Sleep Apnea (OSA) induces deleterious effects in the cardiovascular and nervous systems. We hypothesized that adult patients with preoperative OSA have a higher incidence of postoperative atrial fibrillation and delirium than patients without OSA, after cardiac surgery. METHODS: Sub-analysis of the DECADE trial at Cleveland Clinic hospitals. Our exposure was OSA, defined by STOP-BANG questionnaire score higher than 5 and/or a preoperative diagnosis of OSA. The primary outcome was atrial fibrillation, defined by clinician diagnosis or documented arrhythmia. The secondary outcome was delirium assessed twice during the initial five postoperative days using the Confusion Assessment Method for ICU. We assessed the association between OSA, and atrial fibrillation and delirium using a logistic regression model adjusted for confounders using inverse probability of treatment weighting. RESULTS: 590 patients were included in the final analysis. 133 were diagnosed with OSA and 457 had no OSA. Satisfactory balance between groups for most confounders (absolute standardized difference < 0.10) was achieved after weighting. The atrial fibrillation incidence was 37% (n = 49) in the patients with OSA and 33% (n = 150) in the non-OSA patients. OSA was not associated with atrial fibrillation with an estimated odds ratio of 1.22 (95% CI: 0.75,1.99;p = 0.416). The delirium incidence was 17% (n = 22) in patients with OSA and 15% (n = 67) in the non-OSA patients. OSA was not associated with delirium with an estimated odds ratio of 0.93 (95% CI: 0.51,1.69;p = 0.800). CONCLUSION: In adult patients having cardiac surgery, OSA is not associated with a higher incidence of postoperative atrial fibrillation and delirium. These results suggest different prominent factors rather than OSA affect the incidence of these postoperative outcomes.

Effect of seasons on delirium in postoperative critically ill patients: a retrospective analysis

Abstract Background and objectives Postoperative delirium is common in critically ill patients and is known to have several predisposing and precipitating factors. Seasonality affects cognitive function which has a more dysfunctional pattern during winter. We, therefore, aimed to test whether seasonal variation is associated with the occurrence of delirium and hospital Length Of Stay (LOS) in critically ill non-cardiac surgical populations. Methods We conducted a retrospective analysis of adult patients recovering from non-cardiac surgery at the Cleveland Clinic between March 2013 and March 2018 who stayed in Surgical Intensive Care Unit (SICU) for at least 48 hours and had daily Confusion Assessment Method Intensive Care Unit (CAM-ICU) assessments for delirium. The incidence of delirium and LOS were summarized by season and compared using chi-square test and non-parametric tests, respectively. A logistic regression model was used to assess the association between delirium and LOS with seasons, adjusted for potential confounding variables. Results Among 2300 patients admitted to SICU after non-cardiac surgeries, 1267 (55%) had postoperative delirium. The incidence of delirium was 55% in spring, 54% in summer, 55% in fall and 57% in winter, which was not significantly different over the four seasons (p= 0.69). The median LOS was 12 days (IQR = [8, 19]) overall. There was a significant difference in LOS across the four seasons (p= 0.018). LOS during summer was 12% longer (95% CI: 1.04, 1.21; p= 0.002) than in winter. Conclusions In adult non-cardiac critically ill surgical patients, the incidence of postoperative delirium is not associated with season. Noticeably, LOS was longer in summer than in winter.

Hypoventilation in the PACU is associated with hypoventilation in the surgical ward: Post-hoc analysis of a randomized clinical trial.

OBJECTIVE: To evaluate the association between early postoperative hypoventilation in the last hour of the post-anesthesia care unit (PACU) stay and hypoventilation during the rest of the first 48 postoperative hours in the surgical ward. DESIGN: Sub-analysis of a clinical trial. SETTING: PACU and surgical wards of a single medical center. PATIENTS: Adults having abdominal surgery under general anesthesia. INTERVENTIONS: Monitoring with a respiratory volume monitor from admission to PACU until the earlier of 48 h after surgery or discharge. MEASUREMENTS: The exposure was having at least one low minute-ventilation (MV) event during the last hour of PACU stay, defined as MV lower than 40% the predicted value lasting at least 1 min. The primary outcome was low MV events lasting at least 2 min during the rest of the first 48 postoperative hours, while in the surgical ward. The secondary outcome was the rate of low MV events per monitored hour. MAIN RESULTS: Data of 292 patients were analyzed, of which 20 (6.8%) patients had a low MV event in PACU. Low MV events in the surgical ward were found in 81 (28%) patients. All patients who had low MV events in PACU had events again in the ward, while 61/272 (22%) had an event in the ward but not in PACU. The incidence rate of low MV events per hour was 24 (95% CI: 13, 46) among patients having an event in the PACU, and 2 (1, 4) among those who did not. CONCLUSIONS: In adults recovering from abdominal surgery, events of hypoventilation during the first postoperative hour are associated with similar events during the rest of the first 48 postoperative hours, with positive predictive value approaching 100%. Sixty-one patients had ward hypoventilation that was not preceded by hypoventilation in PACU.

Effect of seasons on delirium in postoperative critically ill patients: a retrospective analysis.

BACKGROUND AND OBJECTIVES: Postoperative delirium is common in critically ill patients and is known to have several predisposing and precipitating factors. Seasonality affects cognitive function which has a more dysfunctional pattern during winter. We, therefore, aimed to test whether seasonal variation is associated with the occurrence of delirium and hospital Length Of Stay (LOS) in critically ill non-cardiac surgical populations. METHODS: We conducted a retrospective analysis of adult patients recovering from non-cardiac surgery at the Cleveland Clinic between March 2013 and March 2018 who stayed in Surgical Intensive Care Unit (SICU) for at least 48 hours and had daily Confusion Assessment Method Intensive Care Unit (CAM-ICU) assessments for delirium. The incidence of delirium and LOS were summarized by season and compared using chi-square test and non-parametric tests, respectively. A logistic regression model was used to assess the association between delirium and LOS with seasons, adjusted for potential confounding variables. RESULTS: Among 2300 patients admitted to SICU after non-cardiac surgeries, 1267 (55%) had postoperative delirium. The incidence of delirium was 55% in spring, 54% in summer, 55% in fall and 57% in winter, which was not significantly different over the four seasons (p = 0.69). The median LOS was 12 days (IQR = [8, 19]) overall. There was a significant difference in LOS across the four seasons (p = 0.018). LOS during summer was 12% longer (95% CI: 1.04, 1.21; p = 0.002) than in winter. CONCLUSIONS: In adult non-cardiac critically ill surgical patients, the incidence of postoperative delirium is not associated with season. Noticeably, LOS was longer in summer than in winter.

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.

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.

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.

Effect of intraoperative subhypnotic infusion of propofol on postoperative nausea and vomiting: A retrospective analysis.

STUDY OBJECTIVE: To measure the possible association between subhypnotic propofol infusion during general balanced anesthesia and the incidence of PONV. DESIGN: Retrospective Cohort Analysis Using Propensity Score Matching. SETTING: Postanesthesia care unit and inpatient unit. PATIENTS: Patients with American Society of Anesthesiologists (ASA) physical status I-IV, undergoing non-cardiac surgery lasting >2 h were included. Patients were excluded if transferred to the intensive care unit after surgery or received ketamine. Initially 70,976 patients were screened, and a cohort of 51,707 eligible adult patients undergoing non-cardiac surgery under general balanced anesthesia between 2015 and 2019 were included. Using a propensity score matching, 3185 patients who received subhypnotic propofol during general balanced anesthesia were matched with 5826 patients who did not receive subhypnotic propofol in a 1:2 ratio. INTERVENTIONS: None. MEASUREMENTS: The primary outcome was the incidence of PONV during PACU stay. The secondary outcome was the incidence of PONV within the first 24 h after surgery. Exploratory outcomes were time-to-extubation and length of hospital stay. MAIN RESULTS: A total of 9011 patients were included (3185 patients who received propofol infusion, and 5826 patients who did not receive propofol infusion) after propensity score matching. The adjusted odds ratio for PONV incidence was 1.03 (95% CI: 0.90, 1.18; p = 0.635) in PACU, and 1.05 (95% CI: 0.90, 1.23; P = 0.50) within 24 h after surgery. The length of hospital stay was 6 h shorter (ratio of means (95% CI) of 0.92, 0.89, 0.94), p < 0.001) and time-to-extubation was 2 min longer (ratio of means 1.24 (1.20, 1.28), p < 0.001) in patients receiving subhypnotic propofol infusion. CONCLUSIONS: Our study suggests that subhypnotic propofol infusion during general balanced anesthesia is not associated with a reduction in the incidence of PONV during PACU stay and within the first 24 h after surgery. However, it is associated with decreased LOS and increased time-to-extubation, but differences in neither outcome were clinically important.

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.

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.

Diurnal blood pressure variation in adults after abdominal surgery-An observational cohort study.

OBJECTIVE: To describe the prevalence of various circadian blood pressure patterns in adults recovering from abdominal surgery, and to evaluate the association between loss of normal circadian variation in blood pressure and hypotension during the initial 2 postoperative days. DESIGN: A post-hoc analysis of data obtained from two randomized trials. SETTING: Operating rooms of the Cleveland Clinic. PATIENTS: Adults having abdominal surgery from 2015 to 2019 with at least one overnight stay. Participants were continuously monitored by wearable vital signs monitors starting in the post-anesthesia care unit and for the first 48 postoperative hours. INTERVENTIONS: None. The exposure of interest was the degree of nocturnal decrease in blood pressure - normal nocturnal decrease in blood pressure ("normal dipping", more than 10% decrease compared to day-time), no nocturnal decrease ("non-dipping", less than 10% nocturnal decrease), or nocturnal increase in blood pressure ("rising"). MEASUREMENTS: Postoperative hypotension, defined by the time weighted average (TWA) area under a mean arterial pressure (MAP) threshold of 70 mmHg. RESULTS: In total, 590 patients were eligible for analysis (mean(SD) age 50(15) years, 56% females, median [IQR] surgery duration 4.0 [2.7, 5.8] hours). Median TWA area under a MAP threshold of 70 mmHg was 0.96 (95%CI 0.59, 1.33) mmHg*minute per monitoring hour lower in patients with either no nocturnal blood pressure decrease (N = 317, 54%), or an increase in nocturnal blood pressure (N = 211, 36%), than in the reference group of patients with normal nocturnal decrease (N = 62, 11%), P < 0.001 for both. CONCLUSIONS: Abnormal diurnal blood pressure patterns are common in adults during the initial 2 days after abdominal surgery. Lack of normal night-time decrease in blood pressure is associated with less postoperative hypotension. Future studies should evaluate whether abnormal postoperative diurnal blood pressure patterns are associated with worse outcomes.