Importance: Early administration of intravenous fluids is recommended for all patients with sepsis, but the association of this treatment with mortality may depend on the patient's initial blood pressure.
Objective: To test the association between early administration of intravenous fluids by paramedics and in-hospital mortality among patients with sepsis, accounting for patients' initial blood pressure.
Design, setting, and participants: Cohort study in which multiple analyses were conducted using a 1-year (from April 1, 2015, to March 31, 2016) cohort of 1871 patients with sepsis who were transported to the hospital by paramedics from a large emergency medical services system in Alberta, Canada. Multivariable logistic regression and a propensity-matched analysis adjusting for baseline patient characteristics were used to minimize confounding by indication and test the association between early administration of intravenous fluids by paramedics and in-hospital mortality. Nonparametric additive regression was used to assess the association of early administration of intravenous fluids with prehospital and in-hospital treatment times.
Exposures: Intravenous fluids administered by paramedics at the point of first contact and during transportation to the hospital.
Main outcomes and measures: The primary outcome was in-hospital mortality. Secondary outcomes included prehospital and emergency department treatment times.
Results: A total of 1871 patients with sepsis were identified (955 women and 916 men; median age, 77 years [interquartile range, 64-85 years]), with an overall in-hospital mortality of 28.2% (n = 528). More than half of patients (1015 [54.2%]) received intravenous fluids from paramedics; the median volume provided was 400 mL (interquartile range, 250-500 mL). The association of intravenous fluids with mortality depended on the patient's initial systolic blood pressure (range, 42-222 mm Hg; P < .001 for interaction). For example, in a typical patient with an initial systolic blood pressure of 100 mm Hg, intravenous fluids were associated with decreased mortality (odds ratio, 0.73; 95% CI, 0.56-0.95), but for a typical patient with the median initial systolic blood pressure of 125 mm Hg, intravenous fluids were not associated with in-hospital mortality (odds ratio, 1.41; 95% CI, 0.81-2.44). Similar results were obtained in the propensity-matched analysis. The administration of intravenous fluids was associated with increased prehospital time compared with patients who did not receive intravenous fluids (median difference, 3.2 minutes; 95% CI, 1.7-4.7 minutes) but was not associated with time to assessment in the emergency department (median difference, 2.4 minutes; 95% CI, -2.4 to 7.3 minutes).
Conclusions and relevance: Intravenous fluids provided by paramedics were associated with reduced in-hospital mortality for patients with sepsis and hypotension but not for those with a higher initial systolic blood pressure.