(1567) Actual Versus Ideal Body Weight for Fluid Resuscitation in Septic Patients

Introduction: The Surviving Sepsis Campaign (SSC) recommends a rapid administration of 30 ml/kg of crystalloid intravenous (IV) fluids within the first 3 hours of sepsis recognition to restore adequate tissue perfusion. The guidelines do not specify whether the 30 ml/kg should be based on actual body weight (ABW) or ideal body weight (IBW).

Methods: Using ICD-10 coding, a retrospective chart review was performed on 125 septic patients presenting to our emergency department between January 1, 2024 through May 1, 2024. Demographics (age, race, sex) were collected. The medication records and provider documentation were reviewed for receipt of IV fluids based on IBW versus ABW. From the time of sepsis recognition based on SIRS criteria, the use and timing of vasopressors within 24-hours, presence of acute kidney injury (AKI), resolution of renal failure within 24-hours, ICU and hospital length of stay (LOS), and inpatient mortality were recorded. Patients without sepsis or septic shock and failure to receive IV fluids within 3 hours were excluded.

Results: Of the 125 patients, 94 (75%) received fluids based on ABW while 31 (25%) received IVF based on IBW. The most common causes of sepsis were pneumonia (50%), urinary tract infection (17%), and skin/soft-tissue infection (6%). Of the 94 patients in ABW group, 33 (35%) required vasopressors at an average of 12.1 hours later. Of the 49 patients with AKI from the ABW group, 28 (57%) had resolution of the AKI within 24-hours. In the IBW group, 15 (50%) required vasopressors with an average of 8.1 hours later. Of the 19 patients with AKI from the IBW group, only 5 (26%) had resolution of the AKI within 24-hours. The average ICU LOS in the ABW and IBW group was 15.3 days and 22.5 days, while the hospital LOS was 23.9 days and 31 days, respectively. The mortality rate in the ABW vs IBW was 16 (17%) and 8 (26%), respectively.

Conclusions: Septic patients given 30 ml/kg of fluids based on ABW rather than IBW had a reduced need of vasopressors, faster resolution of renal failure, shorter length of stay, and reduced mortality. Providers should consider using ABW rather than IBW when calculating fluid requirements in septic patients. A larger trial with a subset analysis of the sepsis etiology is needed to further elucidate this difference.