Urinary Output Predicts Survival in Patients Undergoing Extracorporeal Membrane Oxygenation Following Cardiovascular Surgery.

OBJECTIVES: Extracorporeal membrane oxygenation represents a valuable and rapidly evolving therapeutic option in patients with severe heart or lung failure following cardiovascular surgery. However, survival remains poor and accurate risk stratification challenging. Therefore, we evaluated the predictive value of urinary output within 24 hours after extracorporeal membrane oxygenation initiation on mortality in patients undergoing venoarterial extracorporeal membrane oxygenation support following cardiovascular surgery and aimed to improve established risk prediction models. DESIGN: Single-center, observational registry. SETTING: University-affiliated tertiary care center. PATIENTS: We included 205 patients undergoing veno-arterial extracorporeal membrane oxygenation therapy following cardiovascular surgery at a university-affiliated tertiary-care center into our single-centre registry. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: During a median follow-up time of 35 months (interquartile range, 19-69), 64% of patients died. Twenty-four-hour urinary output was the strongest predictor of outcome among renal function variables with an adjusted hazard ratio per 1 SD of 0.55 (95% CI, 0.40-0.76; p < 0.001) for 30-day mortality and of 0.65 (95% CI, 0.53-0.86; p = 0.002) for 2-year long-term mortality. Most remarkably, 24-hour urinary output showed additional prognostic value beyond that achievable with the simplified acute physiology score-3 and sequential organ failure assessment score indicated by improvements in the category-free net reclassification index for 30-day mortality (simplified acute physiology score-3: 36%, p = 0.015; sequential organ failure assessment score: 36%, p = 0.02), as well as for 2-year mortality (simplified acute physiology score-3: 33%, p = 0.02; sequential organ failure assessment score: 43%, p = 0.005). CONCLUSIONS: We identified 24-hour urinary output as a strong and easily available predictor of mortality in patients undergoing extracorporeal membrane oxygenation therapy following cardiovascular surgery. Implementation of 24-hour urinary output leads to a substantial improvement of established risk prediction models in this vulnerable patient population. These results are particularly compelling because measurement of urinary output is inexpensive and routinely performed in all critical care units.

Effect of hemoadsorption during cardiopulmonary bypass surgery - a blinded, randomized, controlled pilot study using a novel adsorbent.

BACKGROUND: Cardiopulmonary bypass (CPB) surgery initiates a systemic inflammatory response, which is associated with postoperative morbidity and mortality. Hemoadsorption (HA) of cytokines may suppress inflammatory responses and improve outcomes. We tested a new sorbent used for HA (CytoSorb™; CytoSorbents Europe GmbH, Berlin, Germany) installed in the CPB circuit on changes of pro- and anti-inflammatory cytokines levels, inflammation markers, and differences in patients' perioperative course. METHODS: In this first pilot trial, 37 blinded patients were undergoing elective CPB surgery at the Medical University of Vienna and were randomly assigned to HA (n = 19) or control group (n = 18). The primary outcome was differences of cytokine levels (IL-1ß, IL-6, IL-18, TNF-α, and IL-10) within the first five postoperative days. We also analyzed whether we can observe any differences in ex vivo lipopolysaccharide (LPS)-induced TNF-α production, a reduction of high-mobility box group 1 (HMGB1), or other inflammatory markers. Additionally, measurements for fluid components, blood products, catecholamine treatment, bioelectrical impedance analysis (BIA), and 30-day mortality were analyzed. RESULTS: We did not find differences in our primary outcome immediately following the HA treatment, although we observed differences for IL-10 24 hours after CPB (HA: median 0.3, interquartile range (IQR) 0-4.5; control: not traceable, P = 0.0347) and 48 hours after CPB (median 0, IQR 0-1.2 versus not traceable, P = 0.0185). We did not find any differences for IL-6 between both groups, and other cytokines were rarely expressed. We found differences in pretreatment levels of HMGB1 (HA: median 0, IQR 0-28.1; control: median 48.6, IQR 12.7-597.3, P = 0.02083) but no significant changes to post-treatment levels. No differences in inflammatory markers, fluid administration, blood substitution, catecholamines, BIA, or 30-day mortality were found. CONCLUSIONS: We did not find any reduction of the pro-inflammatory response in our patients and therefore no changes in their perioperative course. However, IL-10 showed a longer-lasting anti-inflammatory effect. The clinical impact of prolonged IL-10 needs further evaluation. We also observed strong inter-individual differences in cytokine levels; therefore, patients with an exaggerated inflammatory response to CPB need to be identified. The implementation of HA during CPB was feasible. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01879176, registration date: June 7, 2013.