Fluid-limiting treatment strategies among sepsis patients in the ICU: a retrospective causal analysis

• Published in: Critical care (London, England) England), 2020-02, Vol.24 (1), p.62-9, Article 62
• Main Authors: Shahn, Zach, Shapiro, Nathan I, Tyler, Patrick D, Talmor, Daniel, Lehman, Li-Wei H
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Antibiotics; Care and treatment; Causal inference; Cohort Studies; Critical care; Critical care medicine; Emergency medicine; Emergency Service, Hospital; Estimates; Fluid Therapy; Fluids; Hospital Mortality; Hospital patients; Humans; Intensive care; Intensive care medicine; Intensive Care Units; Intravenous fluids; Length of Stay; Medical centers; Medical research; Methods; Middle Aged; Mortality; Patient outcomes; Patients; Respiration, Artificial; Resuscitation; Retrospective Studies; Sepsis; Sepsis - mortality; Sepsis - therapy; Time; Time Factors; Variables
• ISSN: 1364-8535; 1466-609X; 1466-609X; 1364-8535; 1366-609X
• DOI: 10.1186/s13054-020-2767-0

In septic patients, multiple retrospective studies show an association between large volumes of fluids administered in the first 24 h and mortality, suggesting a benefit to fluid restrictive strategies. However, these studies do not directly estimate the causal effects of fluid-restrictive strategies, nor do their analyses properly adjust for time-varying confounding by indication. In this study, we used causal inference techniques to estimate mortality outcomes that would result from imposing a range of arbitrary limits ("caps") on fluid volume administration during the first 24 h of intensive care unit (ICU) care. Retrospective cohort study SETTING: ICUs at the Beth Israel Deaconess Medical Center, 2008-2012 PATIENTS: One thousand six hundred thirty-nine septic patients (defined by Sepsis-3 criteria) 18 years and older, admitted to the ICU from the emergency department (ED), who received less than 4 L fluids administered prior to ICU admission MEASUREMENTS AND MAIN RESULTS: Data were obtained from the Medical Information Mart for Intensive Care III (MIMIC-III). We employed a dynamic Marginal Structural Model fit by inverse probability of treatment weighting to obtain confounding adjusted estimates of mortality rates that would have been observed had fluid resuscitation volume caps between 4 L-12 L been imposed on the population. The 30-day mortality in our cohort was 17%. We estimated that caps between 6 and 10 L on 24 h fluid volume would have reduced 30-day mortality by - 0.6 to - 1.0%, with the greatest reduction at 8 L (- 1.0% mortality, 95% CI [- 1.6%, - 0.3%]). We found that 30-day mortality would have likely decreased relative to observed mortality under current practice if these patients had been subject to "caps" on the total volume of fluid administered between 6 and 10 L, with the greatest reduction in mortality rate at 8 L.