Features and outcomes of female and male patients requiring postcardiotomy extracorporeal life support.

OBJECTIVES: Although cardiogenic shock requiring extracorporeal life support after cardiac surgery is associated with high mortality, the impact of sex on outcomes of postcardiotomy extracorporeal life support remains unclear with conflicting results in the literature. We compare patient characteristics, in-hospital outcomes, and overall survival between females and males requiring postcardiotomy extracorporeal life support. METHODS: This retrospective, multicenter (34 centers), observational study included adults requiring postcardiotomy extracorporeal life support between 2000 and 2020. Preoperative, procedural, and extracorporeal life support characteristics, complications, and survival were compared between females and males. Association between sex and in-hospital survival was investigated through mixed Cox proportional hazard models. RESULTS: This analysis included 1823 patients (female: 40.8%; median age: 66.0 years [interquartile range, 56.2-73.0 years]). Females underwent more mitral valve surgery (females: 38.4%, males: 33.1%, P = .019) and tricuspid valve surgery (feamales: 18%, males: 12.4%, P < .001), whereas males underwent more coronary artery surgery (females: 45.9%, males: 52.4%, P = .007). Extracorporeal life support implantation was more common intraoperatively in feamales (females: 64.1%, females: 59.1%) and postoperatively in males (females: 35.9%, males: 40.9%, P = .036). Ventricular unloading (females: 25.1%, males: 36.2%, P < .001) and intra-aortic balloon pumps (females: 25.8%, males: 36.8%, P < .001) were most frequently used in males. Females had more postoperative right ventricular failure (females: 24.1%, males: 19.1%, P = .016) and limb ischemia (females: 12.3%, males: 8.8%, P = .23). In-hospital mortality was 64.9% in females and 61.9% in males (P = .199) with no differences in 5-year survival (females: 20%, 95% CI, 17-23; males: 24%, 95% CI, 21-28; P = .069). Crude hazard ratio for in-hospital mortality in females was 1.12 (95% CI, 0.99-1.27; P = .069) and did not change after adjustments. CONCLUSIONS: This study demonstrates that female and male patients requiring postcardiotomy extracorporeal life support have different preoperative and extracorporeal life support characteristics, as well as complications, without a statistical difference in in-hospital and 5-year survivals.

Factors associated with unintended perianesthesia hypothermia.

Background: Our hypothesis was that total intravenous anesthesia (TIVA) is associated with an increase in hypothermia. Methods: Inclusion criteria were patients from the National Anesthesia Clinical Outcomes Registry undergoing a general anesthetic during 2019. Data collected included patient age, sex, American Society of Anesthesiologists physical status classification system score (ASAPS), duration of anesthetic, use of TIVA, type of procedure, and hypothermia. Continuous variables were compared using Student's t test or Mann Whitney rank sum as appropriate. Mixed effects multiple logistic regression was performed to determine the association between independent variables and hypothermia. Results: There was a low incidence of hypothermia (1.2%). Patients who became hypothermic were older, had a higher median ASAPS, and had a higher rate of TIVA. TIVA patients had a significantly increased odds for hypothermia when controlling for covariates. Patients undergoing obstetrical, thoracic, or radiological procedures had increased odds for hypothermia. In a matched cohort subset, TIVA was associated with a greater rate and increased odds for hypothermia. Conclusions: The novel and noteworthy finding was the association between TIVA and perianesthesia hypothermia. Thoracic, radiologic, and obstetrical procedures were associated with greater rates of and odds for hypothermia. Other identified factors can help to stratify patients for risk for hypothermia.

Red Blood Cell Transfusion and Pulmonary Complications: The Society of Thoracic Surgeons Adult Cardiac Surgery Database Analysis.

BACKGROUND: Intraoperative packed red blood cell (PRBC) transfusion during cardiac surgery is associated with increased postoperative morbidity and mortality; however, data on the association between PRBC transfusion and postoperative pulmonary complications (PPCs) are somewhat conflicting. Using The Society of Thoracic Surgeons Adult Cardiac Surgery Database, we sought to determine whether intraoperative PRBC transfusion was associated with PPCs as well as with longer intensive care unit (ICU) stay after isolated coronary artery bypass grafting (CABG) surgery. METHODS: A registry-based cohort study was performed on 751,893 patients with isolated CABG between January 1, 2015, to December 31, 2019. Using propensity score-weighted regression analysis, we analyzed the effect of intraoperative PRBC on the incidence of PPCs (hospital-acquired pneumonia [HAP], mechanical ventilation for >24 hours, or reintubation), ICU length of stay, and ICU readmission. RESULTS: Transfusion of 1, 2, 3, and ≥4 units of PRBCs was associated with increased odds for HAP (odds ratios [ORs], 1.24 [95% CI, 1.21-1.26], 1.28 [95% CI, 1.26-1.32], 1.36 [95% CI, 1.33-1.39], 1.31 [95% CI, 1.28-1.34]), reintubation (ORs, 1.23 [95% CI, 1.21-1.25], 1.38 [95% CI, 1.35-1.40], 1.57 [95% CI, 1.55-1.60], 1.70 [95% CI, 1.67-1.73]), prolonged ventilation (ORs, 1.34 [95% CI, 1.33-1.36], 1.56 [95% CI, 1.53-1.58], 1.97 [95% CI, 1.94-2.00], 2.27 [95% CI, 2.24-2.30]), initial ICU length of stay (mean difference in hours, 6.79 [95% CI, 6.00-7.58], 9.55 [95% CI, 8.71-10.38], 17.26 [95% CI, 16.38-18.15], 22.14 [95% CI, 21.22-23.06]), readmission to ICU (ORs, 1.14 [95% CI, 1.12-1.64], 1.15 [95% CI, 1.12-1.17], 1.15 [95% CI, 1.13-1.18], 1.32 [95% CI, 1.29-1.35]), and additional ICU length of stay (mean difference in hours, 0.55 [95% CI, 0.18-0.92], 0.38 [95% CI, 0.00-0.77], 1.02 [95% CI, 0.61-1.43], 1.83 [95% CI, 1.40-2.26]), respectively. CONCLUSIONS: Intraoperative PRBC transfusion was associated with increased incidence of PPCs, prolonged ICU stay, and ICU readmissions after isolated CABG surgery.

Development and Publication of Clinical Practice Parameters, Reviews, and Meta-analyses: A Report From the Society of Cardiovascular Anesthesiologists Presidential Task Force.

The Society of Cardiovascular Anesthesiologists (SCA) is committed to improving the quality, safety, and value that cardiothoracic anesthesiologists bring to patient care. To fulfill this mission, the SCA supports the creation of peer-reviewed manuscripts that establish standards, produce guidelines, critically analyze the literature, interpret preexisting guidelines, and allow experts to engage in consensus opinion. The aim of this report, commissioned by the SCA President, is to summarize the distinctions among these publications and describe a novel SCA-supported framework that provides guidance to SCA members for the creation of these publications. The ultimate goal is that through a standardized and transparent process, the SCA will facilitate up-to-date education and implementation of best practices by cardiovascular and thoracic anesthesiologists to improve patient safety, quality of care, and outcomes.

Medical Malpractice Claims Related to Performance of Transesophageal Echocardiography by Anesthesiologists.

More than 300,000 adults have cardiac surgery in the United States annually, and most undergo intraoperative transesophageal echocardiography (TEE). This patient population is often older with multiple comorbidities, increasing their risk for complications for even routine procedures. Major morbidity or mortality caused by TEE is rare, and it is unknown how often such complications lead to malpractice lawsuits. The authors identified 13 cases out of 2,564 in a closed claims database that involved TEE and reviewed their etiology. Esophageal injury accounted for most of the suits, and only 2 were related to diagnosis. Most expert reviews deemed the care provided by the anesthesiologist to be appropriate.

Racial and Ethnic Disparities in Veno-Venous Extracorporeal Membrane Oxygenation Mortality for Patients With Severe COVID-19.

Racial/ethnic disparities in mortality were observed during the coronavirus disease-2019 pandemic, but investigations examining the association between race/ethnicity and mortality during extracorporeal membrane oxygenation (ECMO) are limited. We performed a retrospective observational cohort study using the 2020 national inpatient sample. Multivariable logistic regression was used to estimate the odds of mortality in patients of difference race/ethnicity while controlling for confounders. There was a significant association between race/ethnicity and in-hospital mortality ( p < 0.001). Hispanic patients had significantly higher in-hospital mortality compared with White patients (odds ratio [OR] = 1.39, 95% confidence interval [CI] = 1.16-1.67, p < 0.001). Black patients and patients of other races did not have significantly higher in-hospital mortality compared with White patients (OR = 0.82, 95% CI = 0.66-1.02, p = 0.07 and OR = 1.20, 95% CI = 0.92-1.57, p = 0.18). Other variables that had a significant association with mortality included age, insurance type, Charlson comorbidity index, all patient-refined severity of illness, and receipt of care in a low-volume ECMO center (all p < 0.001). Further studies are needed to understand causes of disparities in ECMO mortality.

Sugammadex and blood loss during cervical spine fusion surgery.

Background and Aims: Sugammadex (SUG) has been associated with changes in coagulation studies. Most reports have concluded a lack of clinical significance based on surgical blood loss with SUG use at the end of surgery. Previous reports have not measured its use intraoperatively during ongoing blood loss. Our hypothesis was that the use of SUG intraoperatively may increase bleeding. Material and Methods: This was a single site retrospective study. Inclusion criteria were patients undergoing a primary posterior cervical spine fusion, aged over 18 years, between July 2015 and June 2021. The primary outcomes compared were intraoperative estimated blood loss (EBL) and postoperative drain output (PDO) between patients receiving SUG, neostigmine (NEO) and no NMB reversal agent. The objective was to determine if there was a difference in primary endpoints between patients administered SUG, NEO or no paralytic reversal agent. Primary endpoints were compared using analysis of variance with a P value of 0.05 used to determine statistical significance. Groups were compared using the Chi-squared test, rank sum or student's t test. A logistic regression model was constructed to account for differences between the groups. Results: There was no difference in median EBL or PDO between groups. The use of SUG was not associated with an increase in odds for >500 milliliters (ml) of EBL. Increasing duration of surgery and chronic kidney disease were both associated with an increased risk for EBL >500 ml. Conclusion: Intraoperative use of SUG was not associated with increased bleeding. Any coagulation laboratory abnormalities previously noted did not appear to have an associated clinical significance.

Heterogeneity in Clinical Practices for Post-Cardiotomy Extracorporeal Life Support: a Pilot Survey from the PELS-1 Multicenter Study.

BACKGROUND: High-quality evidence for post-cardiotomy extracorporeal life support (PC-ECLS) management is lacking. This study investigated the real-world PC-ECLS clinical practices. METHODS: This cross-sectional, multi-institutional, international pilot survey explored center organization, anticoagulation management, left ventricular unloading, distal limb perfusion, PC-ECLS monitoring and transfusions practices. Twenty-nine questions were distributed among 34 hospitals participating in the Post-cardiotomy Extra-Corporeal Life Support Study. RESULTS: Of the 32 centers [16 low-volume (50%); 16 high-volume (50%)] that responded, 16 (50%) had dedicated ECLS specialists. Twenty-six centers (81.3%) reported using additional mechanical circulatory supports. Anticoagulation practices were highly heterogeneous: 24 hospitals (75%) reported using patient's bleeding status as a guide, without a specific threshold in 54.2% of cases. Transfusion targets ranged 7-10 g/dL. Most centers used cardiac venting on a case-by-case basis (78.1%) and regular distal limb perfusion (84.4%). Nineteen (54.9%) centers reported dedicated monitoring protocols including daily echocardiography (87.5%), Swan-Ganz catheterization (40.6%), cerebral near-infrared spectroscopy (53.1%) and multimodal assessment of limb ischemia. Inspection of the circuit (71.9%), oxygenator pressure drop (68.8%), plasma free hemoglobin (75%), d-dimer (59.4%), lactate dehydrogenase (56.3%) and fibrinogen (46.9%) are used to diagnose hemolysis and thrombosis. CONCLUSIONS: This study shows remarkable heterogeneity in clinical practices for PC-ECLS management. More standardized protocols and better implementation of available evidence are recommended.

Trajectory of PaO2/FiO2 Ratio in Shock After Angiotensin II.

INTRODUCTION: High-dose catecholamines can impair hypoxic pulmonary vasoconstriction and increase shunt fraction. We aimed to determine if Angiotensin II (Ang-2) is associated with improved PaO2/FiO2 and SpO2/FiO2 in patients in shock. METHODS: Adult patients at four tertiary care centers and one community hospital in the United States who received Ang-2 from July 2018-September 2020 were included in this retrospective, observational cohort study. PaO2, SpO2, and FiO2 were measured at 13 timepoints during the 48-h before and after Ang-2 initiation. Piecewise linear mixed models of PaO2/FiO2 and SpO2/FiO2 were created to evaluate hourly changes in oxygenation after Ang-2 initiation. The difference in the proportion of patients with PaO2/FiO2 ≤ 300 mm Hg at the time of Ang-2 initiation and 48 h after was also examined. RESULTS: The study included 254 patients. In the 48 h prior to Ang-2 initiation, oxygenation was significantly declining (hourly PaO2/FiO2 change -4.7 mm Hg/hr, 95% CI - 6.0 to -3.5, p < .001; hourly SpO2/FiO2 change -3.1/hr, 95% CI-3.7 to -2.4, p < .001). Ang-2 treatment was associated with significant improvements in PaO2/FiO2 and SpO2/FiO2 in the 48-h after initiation (hourly PaO2/FiO2 change +1.5 mm Hg/hr, 95% CI 0.5-2.5, p = .003; hourly SpO2/FiO2 change +0.9/hr, 95% CI 0.5-1.2, p < .001). The difference in the hourly change in oxygenation before and after Ang-2 initiation was also significant (pinteraction < 0.001 for both PaO2/FiO2 and SpO2/FiO2). This improvement was associated with significantly fewer patients having a PaO2/FiO2 ≤ 300 mm Hg at 48 h compared to baseline (mean difference -14.9%, 95% CI -25.3% to -4.6%, p = .011). Subgroup analysis found that patients with either a baseline PaO2/FiO2 ≤ 300 mm Hg or a norepinephrine-equivalent dose requirement >0.2 µg/kg/min had the greatest associations with oxygenation improvement. CONCLUSIONS: Ang-2 is associated with improved PaO2/FiO2 and SpO2/FiO2. The mechanisms for this improvement are not entirely clear but may be due to catecholamine-sparing effect or may also be related to improved ventilation-perfusion matching, intrapulmonary shunt, or oxygen delivery.

The Relation Between Obesity and Mortality in Postcardiotomy Venoarterial Membrane Oxygenation.

BACKGROUND: Obesity is an important health problem in cardiac surgery and among patients requiring postcardiotomy venoarterial extracorporeal membrane oxygenation (V-A ECMO). Still, whether these patients are at risk for unfavorable outcomes after postcardiotomy V-A ECMO remains unclear. The current study evaluated the association between body mass index (BMI) and in-hospital outcomes in this setting. METHODS: The Post-cardiotomy Extracorporeal Life Support (PELS-1) study is an international, multicenter study. Patients requiring postcardiotomy V-A ECMO in 36 centers from 16 countries between 2000 and 2020 were included. Patients were divided in 6 BMI categories (underweight, normal weight, overweight, class I, class II, and class III obesity) according to international recommendations. Primary outcome was in-hospital mortality, and secondary outcomes included major adverse events. Mixed logistic regression models were applied to evaluate associations between BMI and mortality. RESULTS: The study cohort included 2046 patients (median age, 65 years; 838 women [41.0%]). In-hospital mortality was 60.3%, without statistically significant differences among BMI classes for in-hospital mortality (P = .225) or major adverse events (P = .126). The crude association between BMI and in-hospital mortality was not statistically significant after adjustment for comorbidities and intraoperative variables (class I: odds ratio [OR], 1.21; 95% CI, 0.88-1.65; class II: OR, 1.45; 95% CI, 0.86-2.45; class III: OR, 1.43; 95% CI, 0.62-3.33), which was confirmed in multiple sensitivity analyses. CONCLUSIONS: BMI is not associated to in-hospital outcomes after adjustment for confounders in patients undergoing postcardiotomy V-A ECMO. Therefore, BMI itself should not be incorporated in the risk stratification for postcardiotomy V-A ECMO.

In Vitro Analysis of Platelet Adhesion, Aggregation, and Surface GP1bα Expression in Stored Refrigerated Whole Blood: A Pilot Study.

BACKGROUND: Warm, fresh whole blood (WB) has been used by the US military to treat casualties in Iraq and Afghanistan. Based on data in that setting, cold-stored WB has been used to treat hemorrhagic shock and severe bleeding in civilian trauma patients in the United States. In an exploratory study, we performed serial measurements of WB's composition and platelet function during cold storage. Our hypothesis was that in vitro platelet adhesion and aggregation would decrease over time. METHODS: WB samples were analyzed on storage days 5, 12, and 19. Hemoglobin, platelet count, blood gas parameters (pH, Po2, Pco2, and Spo2), and lactate were measured at each timepoint. Platelet adhesion and aggregation under high shear were assessed with a platelet function analyzer. Platelet aggregation under low shear was assessed using a lumi-aggregometer. Platelet activation was assessed by measuring dense granule release in response to high-dose thrombin. Platelet GP1bα levels were measured with flow cytometry, as a surrogate for adhesive capacity. Results at the 3 study timepoints were compared using repeat measures analysis of variance and post hoc Tukey tests. RESULTS: Measurable platelet count decreased from a mean of (163 + 53) × 109 platelets per liter at timepoint 1 to (107 + 32) × 109 at timepoint 3 (P = .02). Mean closure time on the platelet function analyzer (PFA)-100 adenosine diphosphate (ADP)/collagen test increased from 208.7 + 91.5 seconds at timepoint 1 to 390.0 + 148.3 at timepoint 3 (P = .04). Mean peak granule release in response to thrombin decreased significantly from 0.7 + 0.3 nmol at timepoint 1 to 0.4 + 0.3 at timepoint 3 (P = .05). Mean GP1bα surface expression decreased from 232,552.8 + 32,887.0 relative fluorescence units at timepoint 1 to 95,133.3 + 20,759.2 at timepoint 3 (P < .001). CONCLUSIONS: Our study demonstrated significant decreases in measurable platelet count, platelet adhesion, and aggregation under high shear, platelet activation, and surface GP1bα expression between cold-storage days 5 and 19. Further studies are needed to understand the significance of our findings and to what degree in vivo platelet function recovers after WB transfusion.

Factor VIII: A Dynamic Modulator of Hemostasis and Thrombosis in Trauma.

A trace amount of thrombin cleaves factor VIII (FVIII) into an active form (FVIIIa), which catalyzes FIXa-mediated activation of FX on the activated platelet surface. FVIII rapidly binds to von Willebrand factor (VWF) after secretion and becomes highly concentrated via VWF-platelet interaction at a site of endothelial inflammation or injury. Circulating levels of FVIII and VWF are influenced by age, blood type (nontype O > type O), and metabolic syndromes. In the latter, hypercoagulability is associated with chronic inflammation (known as thrombo-inflammation). In acute stress including trauma, releasable pools of FVIII/VWF are secreted from the Weibel-Palade bodies in the endothelium and then augment local platelet accumulation, thrombin generation, and leukocyte recruitment. Early systemic increases of FVIII/VWF (>200% of normal) levels in trauma result in a lower sensitivity of contact-activated clotting time (activated partial thromboplastin time [aPTT] or viscoelastic coagulation test [VCT]). However, in severely injured patients, multiple serine proteases (FXa plasmin and activated protein C [APC]) are locally activated and may be systemically released. Severity of traumatic injury correlates with prolonged aPTT and elevated activation markers of FXa, plasmin, and APC, culminating in a poor prognosis. In a subset of acute trauma patients, cryoprecipitate that contains fibrinogen, FVIII/VWF, and FXIII is theoretically advantageous over purified fibrinogen concentrate to promote stable clot formation, but comparative efficacy data are lacking. In chronic inflammation or subacute phase of trauma, elevated FVIII/VWF contributes to the pathogenesis of venous thrombosis by enhancing not only thrombin generation but also augmenting inflammatory functions. Future developments in coagulation monitoring specific to trauma patients, and targeted to enhancement or inhibition of FVIII/VWF, are likely to help clinicians gain better control of hemostasis and thromboprophylaxis. The main goal of this narrative is to review the physiological functions and regulations of FVIII and implications of FVIII in coagulation monitoring and thromboembolic complications in major trauma patients.