AbstractBackgroundRed blood cell (RBC) transfusion is common in surgical patients, yet optimal transfusion targets are incompletely defined in the perioperative period. Hemoglobin levels at the time of hospital discharge may provide insight into transfusion practices, anemia management, and patient outcomes.Study Design and MethodsThis is an observational cohort study of adults receiving RBC transfusion during noncardiac surgery from 2010 to 2014. Multivariable regression was used to assess the relationships between hospital discharge hemoglobin concentrations, anemia severity (severe: <8 g/dL; moderate: 8‐10 g/dL; mild/none: ≥10 g/dL), and clinical outcomes, including a primary outcome of 30‐day hospital readmission and secondary outcomes of posthospitalization RBC transfusion, composite stroke or myocardial infarction, and mortality.ResultsA total of 3129 patients were included: 165 (5%) with severe discharge anemia, 1962 (63%) moderate, and 1002 (32%) with mild/none. Five hundred ninety‐two (19%) were readmitted, with the highest rates observed with severe anemia (26% vs 19% for mild/none). Readmissions were not significantly different after multivariable adjustment (overall P = .216); however, in those receiving postoperative intensive care, severe anemia was associated with increased readmission rates (hazard ratio [HR], 1.72; 95% confidence interval [CI], 1.09‐2.71; reference mild/none]. Posthospitalization RBC transfusion rates were highest with severe anemia (25% vs 10% for mild/none; adjusted HR, 2.2; 95% CI, 1.5‐3.3; P < .001). There were no significant differences in composite stroke/myocardial infarction, or mortality. RBC transfusion volumes did not modify anemia‐outcome relationships.ConclusionHospital discharge hemoglobin values for transfused surgical patients were not associated with hospital readmission rates except for those receiving postoperative intensive care. Further evaluation is warranted to understand downstream consequences of postsurgical anemia.
Renal Function Parameters and Serum Sodium Enhance Prediction of Wait‐List Outcomes in Pediatric Liver Transplantation
Background and Aims Reliance on exception points to prioritize children for liver transplantation (LT) stems from concerns that the Pediatric End‐Stage Liver Disease (PELD) score underestimates mortality. Renal dysfunction and serum sodium disturbances are negative prognosticators in adult LT candidates and various pediatric populations, but are not accounted for in PELD. We retrospectively evaluated the effect of these parameters in predicting 90‐day wait‐list death/deterioration among pediatric patients (<12 years) listed for isolated LT in the United States between February 2002 and June 2018. Approach and Results Among 4,765 patients, 2,303 (49.3%) were transplanted, and 231 (4.8%) died or deteriorated beyond transplantability within 90 days of listing. Estimated glomerular filtration rate (eGFR) (hazard ratio [HR] 1.09 per 5‐unit decrease, 95% confidence interval [CI] 1.06‐1.10) and dialysis (HR 7.24, 95% CI 3.57‐14.66) were univariate predictors of 90‐day death/deterioration (P < 0.001). The long‐term benefit of LT persisted in patients with renal dysfunction, with LT as a time‐dependent covariate conferring a 2.4‐fold and 17‐fold improvement in late survival among those with mild and moderate‐to‐severe dysfunction, respectively. Adjusting for PELD, sodium was a significant nonlinear predictor of outcome, with 90‐day death/deterioration risk increased at both extremes of sodium (HR 1.20 per 1‐unit decrease below 137 mmol/L, 95% CI 1.16‐1.23; HR per 1‐unit increase above 137 mmol/L 1.13, 95% CI 1.10‐1.17, P < 0.001). A multivariable model incorporating PELD, eGFR, dialysis, and sodium demonstrated improved performance and superior calibration in predicting wait‐list outcomes relative to the PELD score. Conclusions Listing eGFR, dialysis, and serum sodium are potent, independent predictors of 90‐day death/deterioration in pediatric LT candidates, capturing risk not accounted for by PELD. Incorporation of these variables into organ allocation systems may highlight patient subsets with previously underappreciated risk, augment ability of PELD to prioritize patients for transplantation, and ultimately mitigate reliance on nonstandard exceptions.
Essential Role of Patient Blood Management in a Pandemic: A Call for Action
The World Health Organization (WHO) has declared coronavirus disease 2019 (COVID-19), the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a pandemic. Global health care now faces unprecedented challenges with widespread and rapid human-to-human transmission of SARS-CoV-2 and high morbidity and mortality with COVID-19 worldwide. Across the world, medical care is hampered by a critical shortage of not only hand sanitizers, personal protective equipment, ventilators, and hospital beds, but also impediments to the blood supply. Blood donation centers in many areas around the globe have mostly closed. Donors, practicing social distancing, some either with illness or undergoing self-quarantine, are quickly diminishing. Drastic public health initiatives have focused on containment and “flattening the curve” while invaluable resources are being depleted. In some countries, the point has been reached at which the demand for such resources, including donor blood, outstrips the supply. Questions as to the safety of blood persist. Although it does not appear very likely that the virus can be transmitted through allogeneic blood transfusion, this still remains to be fully determined. As options dwindle, we must enact regional and national shortage plans worldwide and more vitally disseminate the knowledge of and immediately implement patient blood management (PBM). PBM is an evidence-based bundle of care to optimize medical and surgical patient outcomes by clinically managing and preserving a patient’s own blood. This multinational and diverse group of authors issue this “Call to Action” underscoring “The Essential Role of Patient Blood Management in the Management of Pandemics” and urging all stakeholders and providers to implement the practical and commonsense principles of PBM and its multiprofessional and multimodality approaches.
Anemia in Critically Ill Patients With Acute Respiratory Distress Syndrome and Posthospitalization Physical Outcomes
Objective: Anemia is common during critical illness and often persists after hospital discharge; however, its potential association with physical outcomes after critical illness is unclear. Our objective was to assess the associations between hemoglobin at intensive care unit (ICU) and hospital discharge with physical status at 3-month follow-up in acute respiratory distress syndrome (ARDS) survivors. Methods: This is a secondary analysis of a multisite prospective cohort study of 195 mechanically ventilated ARDS survivors from 13 ICUs at 4 teaching hospitals in Baltimore, Maryland. Multivariable regression was utilized to assess the relationships between ICU and hospital discharge hemoglobin concentrations with measures of physical status at 3 months, including muscle strength (Medical Research Council sumscore), exercise capacity (6-minute walk distance [6MWD]), and self-reported physical functioning (36-Item Short-Form Health Survey [SF-36v2] Physical Function score and Activities of Daily Living [ADL] dependencies). Results: Median (interquartile range) hemoglobin concentrations at ICU and hospital discharge were 9.5 (8.5-10.7) and 10.0 (9.0-11.2) g/dL, respectively. In multivariable regression analyses, higher ICU discharge hemoglobin concentrations (per 1 g/dL) were associated with greater 3-month 6MWD mean percent of predicted (3.7% [95% confidence interval 0.8%-6.5%]; P = .01) and fewer ADL dependencies (−0.2 [−0.4 to −0.1]; P = .02), but not with percentage of maximal muscle strength (0.7% [−0.9 to 2.3]; P = .37) or SF-36v2 normalized Physical Function scores (0.8 [−0.3 to 1.9]; P = .15). The associations of physical outcomes and hospital discharge hemoglobin concentrations were qualitatively similar, but none were statistically significant. Conclusions: In ARDS survivors, higher hemoglobin concentrations at ICU discharge, but not hospital discharge, were significantly associated with improved exercise capacity and fewer ADL dependencies. Future studies are warranted to further assess these relationships.
Ratios of Plasma and Platelets to Red Blood Cells in Surgical Patients With Acute Intraoperative Hemorrhage
BACKGROUND: The relationships between the ratios of transfused allogeneic blood products and clinical outcomes in patients with acute intraoperative hemorrhage are poorly defined. METHODS: To better define these ratios, we undertook a single-center, observational cohort study of all surgical patients (≥18 years) who received rapid transfusion defined by a critical administration threshold of 3 or more units of red blood cells (RBCs) intraoperatively within 1 hour between January 1, 2011 and December 31, 2015. Multivariable regression analyses were used to assess relationships between ratios of plasma to RBCs and platelets to RBCs at 3, 12, and 24 hours and clinical outcomes. The primary outcome was hospital mortality, with secondary outcomes of intensive care unit and hospital-free days. RESULTS: The study included 2385 patients, of whom 14.9% had a plasma-to-RBC ratio of 1.0+, and 47.6% had a platelet-to-RBC ratio of 1.0+. Higher plasma-to-RBC and platelet-to-RBC ratios were observed for patients who underwent cardiac, transplant, and vascular surgery and in patients with greater derangements in hemostatic laboratory values. Ratios did not differ by patient age or severity of illness. Higher ratios were not associated with improved clinical outcomes. Mortality differed by platelet-to-RBC but not plasma-to-RBC ratio, with the highest mortality observed with a platelet-to-RBC ratio of 0.1–0.9 at 24 hours (odds ratio, 3.34 [1.62–6.88]) versus no platelets ( P = .001). Higher plasma-to-RBC ratios were associated with decreased hospital-free days, although differences in clinical outcomes were not significant after exclusion of patients receiving only RBCs without component therapies. CONCLUSIONS: Transfusion ratios in surgical patients with critical intraoperative hemorrhage were largely related to surgical and hemostatic features rather than baseline patient characteristics. Higher ratios were not associated with improved outcomes.
1479: TRANSFUSION PRODUCT RATIOS DURING LIFE-THREATENING HEMORRHAGE IN THE ABSENCE OF TRAUMA OR SURGERY
Abstract Background: Use of direct-acting oral anticoagulants (DOAC) is increasingly common among patients with atrial fibrillation and venous thromboembolic disease. Differences in the mechanisms of action as compared to warfarin could impact transfusion patterns and clinical outcomes in patients, especially for those presenting with major hemorrhage. The management of patients taking these newer medications and corresponding outcomes are relevant to optimizing clinical decision making in situations of major hemorrhage. Methods: We tested the hypothesis that inpatient all-cause mortality among patients presenting with major hemorrhage differs based on the home-administered anticoagulant medication class (DOAC versus warfarin). A cohort of patients presenting to twelve US hospitals from 2013 to 2016 was identified using the Recipient Epidemiology and Donor Evaluation Study (REDS)-III Recipient Database. Primary ICD diagnosis codes, issued blood products, laboratory data, and early mortality events were used in the application of the International Society on Thrombosis and Hemostasis definition of major hemorrhage. Exposure status was defined as a record of home-administered DOAC (apixaban, dabigatran, edoxaban, or rivaroxaban; exposed) or warfarin (non-exposed). Patients with multiple encounters and those transferred into or out of network were excluded from the analysis. Proportional hazards regression was used to compare all-cause mortality and hospital length of stay. We then repeated the analysis using a cohort matched on propensity scores to account for confounding by age, gender, concurrent aspirin and anti-platelet use, liver and renal dysfunction, cancer, CHA2DS2-VASc score, traumatic injury, and hospital. We then repeated the propensity score matched analysis stratified by anatomic location of bleed and traumatic injury. Results: More than 1.5 million hospitalizations were screened for eligibility. Exclusion of minors, outpatients, hospitalizations without a medication of interest, absence of major hemorrhage, multiple hospitalizations, and hospital transfers resulted in 3,731 patients available for the unadjusted analysis. Inpatient all-cause mortality was lower among DOAC users when the entire cohort was considered (HR = 0.60, 95%CI 0.45 - 0.80, p=0.0005). Implementation of propensity score matching to account for confounding abrogated this difference (HR=0.84, 95%CI 0.58 - 1.22, p=0.36). Time to hospital discharge was shorter for DOAC users (HR = 1.17, 95%CI 1.05 - 1.30, p=0.0034). Transfusion patterns were similar by medication, except for plasma transfusion occurring in 42% of warfarin encounters and 11% of DOAC encounters. Vitamin K was administered in 63% of warfarin encounters, whereas specific DOAC reversal agents were largely unavailable during the analysis period [used in 5 (1%) DOAC encounters]. There were no statistically significant differences in inpatient all-cause mortality in the stratified analysis (warfarin as reference): HR = 0.69 (95%CI 0.31 - 1.55) for traumatic head injuries; HR = 1.10 (95%CI 0.62 - 1.95) for non-traumatic head injuries; HR = 0.62 (95%CI 0.20 - 1.94) for traumatic, non-head injuries; and HR = 0.69 (95%CI 0.29 - 1.63) for non-traumatic, non-head injuries. Conclusions: Analysis of a population taking oral anticoagulation and presenting with major hemorrhage showed that transfusion of plasma was more commonly employed to treat major hemorrhage among warfarin users than DOAC users. Inpatient all-cause mortality was lower among DOAC users in the overall cohort; however, accounting for potential confounding factors using propensity score matching abrogated this difference. Hospital length of stay was shorter for DOAC users compared to warfarin users. Stratification by location of bleed and traumatic injury did not alter these findings. Less plasma use and a shorter length of hospitalization in this study, combined with no observable difference in inpatient all-cause mortality, suggests that outcomes following major hemorrhage are at least no different for DOAC users as compared to warfarin users. Disclosures Mast: Novo Nordisk: Research Funding. Kor:NIH: Consultancy; NIH: Research Funding; UpToDate: Patents & Royalties; CSL Behring: Honoraria.
The Association between Prehospital Vulnerability, ARDS Development, and Mortality among At-Risk Adults. Results from the LIPS-A Clinical Trial
Abstract Rationale No previous studies have examined the role of prehospital vulnerability in acute respiratory distress syndrome (ARDS) development and mortality in an acutely ill adult population. Objectives To describe the association between prehospital vulnerability and 1) the development of ARDS, 2) 28-day mortality, and 3) 1-year mortality. Methods This was a longitudinal prospective cohort study nested within the multicenter LIPS-A (Lung Injury Prevention Study-Aspirin) trial. We analyzed 301 participants who completed Vulnerable Elders Survey (VES) at baseline. Multivariable logistic regression and Cox regression analyses were used to describe the association between vulnerability and short-term outcomes (ARDS and 28-day mortality) and long-term outcomes (1-year mortality), respectively. Results The VES score ranged from 0 to 10 (median [interquartile range], 2.0 [0–6]); 143 (47.5%) fit criteria for prehospital vulnerability (VES ≥ 3). Vulnerability was not significantly associated with ARDS development (10 [7.0%] vulnerable patients developed ARDS as per LIPS-A study criteria vs. 20 [12.7%] without vulnerability; P = 0.10; adjusted odds ratio [95% confidence interval (CI)], 0.54 [0.24–1.24]; P = 0.15). Nor was vulnerability associated with 28-day mortality (15 [10.5%] vulnerable patients were dead by Day 28 vs. 11 [7.0%] nonvulnerable patients; P = 0.28; adjusted odds ratio [95% CI], 0.95 [0.39–2.26]; P = 0.90). Vulnerability was significantly associated with 1-year mortality in hospital survivors (35 [26.9%] vs. 13 [9.3%]; adjusted hazard ratio [95% CI], 2.20 [1.10–4.37]; P = 0.02). Conclusions In a population of adults recruited for their high risk of ARDS, prehospital vulnerability, measured by VES, was highly prevalent and strongly associated with 1-year mortality.
Initial Postoperative Hemoglobin Values and Clinical Outcomes in Transfused Patients Undergoing Noncardiac Surgery
BACKGROUND: Intraoperative red blood cell (RBC) transfusion is common, yet transfusion strategies remain controversial as pretransfusion hemoglobin triggers are difficult to utilize during acute bleeding. Alternatively, postoperative hemoglobin values may provide useful information regarding transfusion practices, though optimal targets remain undefined. METHODS: This is a single-center observational cohort study of adults receiving allogeneic RBCs during noncardiac surgery from 2010 through 2014. Multivariable regression analyses adjusting for patient illness, laboratory derangements, and surgical features were used to assess relationships between initial postoperative hemoglobin values and a primary outcome of hospital-free days. RESULTS: A total of 8060 patients were included. Those with initial postoperative hemoglobin <7.5 or ≥11.5 g/dL had decreased hospital-free days [mean (95% confidence interval [CI]), −1.45 (−2.50 to −0.41) and −0.83 (−1.42 to −0.24), respectively] compared to a reference range of 9.5–10.4 g/dL (overall P value .003). For those with hemoglobin <7.5 g/dL, the odds (95% CI) for secondary outcomes included acute kidney injury (AKI) 1.43 (1.03–1.99), mortality 2.10 (1.18–3.74), and cerebral ischemia 3.12 (1.08–9.01). The odds for postoperative mechanical ventilation with hemoglobin ≥11.5 g/dL were 1.33 (1.07–1.65). Secondary outcome associations were not significant after multiple comparisons adjustment (Bonferroni P < .0056). CONCLUSIONS: In transfused patients, postoperative hemoglobin values between 7.5 and 11.5 g/dL were associated with superior outcomes compared to more extreme values. This range may represent a target for intraoperative transfusions, particularly during active bleeding when pretransfusion hemoglobin thresholds may be impractical or inaccurate. Given similar outcomes within this range, targeting hemoglobin at the lower aspect may be preferable, though prospective validation is warranted.