The Effect of Body Mass Index and Weight-Adjusted Fluid Dosing on Mortality in Sepsis.

PURPOSE: The Surviving Sepsis Campaign guidelines recommend 30 mL/kg of fluids within 3 hours (30by3) of sepsis-induced hypoperfusion, but a national mandate released an allowance for dosing based on ideal instead of actual body weight (IBW/ABW) for obese patients. This study aims to determine the dose-effect of 30by3 for patients with severe sepsis or septic shock (SS/SS) with respect to body mass index (BMI) categories and secondarily, examine the clinical impact of IBW vs. ABW-based dosing. METHODS: Retrospective cohort study of adults (≥18 years; n = 1,032) with SS/SS presenting to an urban, tertiary-care emergency department. Models include MEDS score, antibiotic timing, lactate, renal and heart failure, among others. RESULTS: The cohort was 10.2% underweight and 28.7% obese. Overall mortality was 17.1% with 20.4% shock mortality. An exponential increase in mortality was observed for each 5 mL/kg under 30by3 for underweight (p = 0.02), but not obese patients. ABW vs IBW-30by3 dosing was reached in 80.0 vs 52.4% (underweight), 56.4 vs 56.9% (normal/overweight), and 23.3 vs 46.0% (obese). Across all BMI categories, there was increased mortality for not reaching ABW-based 30by3 dosing (OR 1.78, 95% CI 1.18-2.69) with no significant impact for IBW (OR 1.28, 95% CI 0.87 -1.91). The increased mortality for failing to reach ABW-dosed 30by3 remained for underweight patients ABW (OR 5.82, 95% CI 1.32-25.57) but not obese patients. Longer ICU stays were observed for not reaching 30by3 based on ABW (ß = 2.40, 95% CI 0.84-3.95) and IBW dosing (ß = 1.58, 95% CI 0.07-3.08) overall. This effect remained for obese and underweight (except IBW dosing) patients. CONCLUSIONS: An exponential, dose-effect increase in mortality was observed for underweight patients not receiving 30by3. Therefore, the mortality impact of under-dosing may be amplified using ABW for underweight patients. Fluid dosing did not impact mortality for obese patients, but we caution against deviation from guidelines without further studies.

The effect of delays in second-dose antibiotics on patients with severe sepsis and septic shock.

BACKGROUND: Early antibiotics are fundamental to sepsis management. Second-dose antibiotic delays were associated with increased mortality in a recent study. Study objectives include: 1) determine factors associated with delays in second-dose antibiotic administration; 2) evaluate if delays influence clinical outcomes. METHODS: ED-treated adults (≥18 years; n = 1075) with severe sepsis or septic shock receiving ≥2 doses of intravenous antibiotics were assessed, retrospectively, for second-dose antibiotic delays (dose time > 25% of recommended interval). Predictors of delay and impact on outcomes were determined, controlling for MEDS score, 30 mL/kg fluids and antibiotics within three hours of sepsis onset, lactate, and renal failure, among others. RESULTS: In total, 335 (31.2%) patients had delayed second-dose antibiotics. A total of 1864 second-dose antibiotics were included, with 354 (19.0%) delays identified by interval (delayed/total doses): 6-h (36/67) = 53.7%; 8-h (165/544) = 30.3%; 12-h (114/436) = 26.1%; 24-h (21/190) = 8.2%; 48-h (0/16) = 0%. In-hospital mortality in the timely group was 15.5% (shock-17.6%) and 13.7% in the delayed group (shock-16.9%). Increased odds of delay were observed for ED boarding (OR 2.54, 95% 1.81-3.55), shorter dosing intervals (6/8-h- OR 2.99, 95% CI 1.95-4.57; 12-h- OR 2.46, 95% CI 1.72-3.51), receiving 30 mL/kg fluids by three hours (OR 1.42, 95% CI 1.06-1.90), and renal failure (OR 2.57, 95% CI 1.50-4.39). Delays were not associated with increased mortality (OR 0.87, 95% CI 0.58-1.29) or other outcomes. CONCLUSIONS: Factors associated with delayed second-dose antibiotics include ED boarding, antibiotics requiring more frequent dosing, receiving 30 mL/kg fluid, and renal failure. Delays in second-dose administration were not associated with mortality or other outcomes.

Evaluation and Predictors of Fluid Resuscitation in Patients With Severe Sepsis and Septic Shock.

OBJECTIVES: Rapid fluid resuscitation has become standard in sepsis care, despite "low-quality" evidence and absence of guidelines for populations "at risk" for volume overload. Our objectives include as follows: 1) identify predictors of reaching a 30 mL/kg crystalloid bolus within 3 hours of sepsis onset (30by3); 2) assess the impact of 30by3 and fluid dosing on clinical outcomes; 3) examine differences in perceived "at-risk" volume-sensitive populations, including end-stage renal disease, heart failure, obesity, advanced age, or with documentation of volume "overload" by bedside examination. DESIGN: Retrospective cohort study. All outcome analyses controlled for sex, end-stage renal disease, heart failure, sepsis severity (severe sepsis vs septic shock), obesity, Mortality in Emergency Department Sepsis score, and time to antibiotics. SETTING: Urban, tertiary care center between January 1, 2014, and May 31, 2017. PATIENTS: Emergency Department treated adults (age ≥18 yr; n = 1,032) with severe sepsis or septic shock. INTERVENTIONS: Administration of IV fluids by bolus. MEASUREMENTS AND MAIN RESULTS: In total, 509 patients received 30by3 (49.3%). Overall mortality was 17.1% (n = 176), with 20.4% mortality in the shock group. Patients who were elderly (odds ratio, 0.62; 95% CI, 0.46-0.83), male (odds ratio, 0.66; CI, 0.49-0.87), obese (odds ratio, 0.18; CI, 0.13-0.25), or with end-stage renal disease (odds ratio, 0.23; CI, 0.13-0.40), heart failure (odds ratio, 0.42; CI, 0.29-0.60), or documented volume "overload" (odds ratio, 0.30; CI, 0.20-0.45) were less likely to achieve 30by3. Failure to meet 30by3 had increased odds of mortality (odds ratio, 1.52; CI, 1.03-2.24), delayed hypotension (odds ratio, 1.42; CI, 1.02-1.99), and increased ICU stay (~2 d) (ß = 2.0; CI, 0.5-3.6), without differential effects for "at-risk" groups. Higher fluid volumes administered by 3 hours correlated with decreased mortality, with a plateau effect between 35 and 45 mL/kg (p < 0.05). CONCLUSIONS: Failure to reach 30by3 was associated with increased odds of in-hospital mortality, irrespective of comorbidities. Predictors of inadequate resuscitation can be identified, potentially leading to interventions to improve survival. These findings are retrospective and require future validation.