2025 Southeastern Residency Conference

Safety of Initial Fluid Bolus in Overweight and Obese Patients with Sepsis in the Emergency Department: A Retrospective Review 


Aana Hampton-Ashford, Caroline Cox 
 
Background:  
Sepsis is a severe condition caused by an uncontrolled inflammatory response to infection. Approximately 80% of patients with sepsis receive initial treatment in the emergency department (ED). The Surviving 
Sepsis Guidelines recommend an initial fluid bolus of 30 mL/kg. However, these guidelines do not provide 
additional recommendations for obese patients. The US Centers of Medicare and Medicaid Services state 
that ideal body weight may be used to calculate the 30 mL/kg fluid bolus for obese patients with a body 
mass index (BMI) of ≥ 30 kg/m2. The purpose of this study aimed to compare the incidence of fluid 
overload between normal or overweight patients and obese patients that presented to the emergency with sepsis and received a 30 mL/kg fluid bolus. 
 
Methods:  
This study was a retrospective cohort chart review across emergency departments within the Wellstar Health System from January 1, 2024, to July 24, 2024. Adult patients were included if they presented to the ED, 
triggered a sepsis Best Practice Alert, and received a 30 mL/kg fluid bolus. Exclusion criteria included a BMI of less than 18.5 kg/m2, palliative care or withdrawal of care within 24 hours of arrival, transfer from outside hospital, pregnant and incarcerated patients, history of heart failure, diuretic use prior to arrival, chronic
kidney disease stage 4 or 5, and liver disease. Patients were separated into two groups based on BMI. 
Group 1 included 97 patients categorized as normal weight or overweight with a BMI of 18.5-29.9 kg/m2. 
Group 2 included 97 patients categorized as obese with a BMI greater than or equal to 30 kg/m2. The 
primary outcome was the incidence of fluid overload. Fluid overload was defined as documentation of new pitting edema, crackles or anasarca within 24 hours, chest x-ray findings of pulmonary vascular 
congestion, pulmonary edema, and/or pleural effusion that is new compared to chest x-ray on admission,
and/or loop diuretic administration or initiation of renal replacement within 24 hours. Secondary outcomes 
included mortality within 72 hours and hospital length of stay. 
 
Results:  
The study aimed to evaluate 194 patients, however only 165 patients met inclusion criteria. Patients in 
group 2 were most commonly excluded due to heart failure, prior diuretic use, and/or palliative care. This 
resulted in 97 patients in group 1 (BMI 18.5-29.9 kg/m²) and 68 patients in group 2 (BMI ≥30 kg/m²). Groups 1 and 2 had similar baseline characteristics, including age, BMI (25.6 kg/m2 vs. 37kg/m2, p=.70), gender
distribution, height, race, and study site. However, differences were observed in infection sources, with 
urinary tract infections being more common in group 1.  
There was no difference in the primary outcome of fluid overload between groups 1 and 2 (13.2% vs. 5.2%, p = 0.06). There was no difference between groups when comparing each individual component of the fluid overload definition. Secondary outcomes, including 72-hour mortality (5% vs. 4%, p = 0.15) and hospital 
length of stay (114 hours vs. 177 hours, p = 0.274), showed no significant difference. 
 
 
Conclusion: 
Despite concerns of increased fluid overload risk in obese patients receiving a 30 mL/kg sepsis fluid bolus, this study found no significant difference between BMI groups, likely due to similar baseline BMI. In this 
study, patient BMI groups were not different at baseline, possibly preventing an accurate comparison of 
obese patients compared to normal and overweight patients receiving a weight-based fluid bolus for 
sepsis. To improve future research, groups should include patients with BMI less than 25 kg/m² and greater than 40 kg/m² to ensure meaningful BMI differences at baseline. This adjustment would better assess the 
impact of weight-based fluid boluses on sepsis management.