Jason K Lee, Lisa E Vaughan, Kimberly D Cureton, Kianoush B Kashani
To our knowledge, this is the first retrospective analysis to compare early versus late vasopressin initiation in septic shock while using defined temporal thresholds and a delineated exposure window. Within the temporal definitions used in this retrospective analysis, we did not find that earlier vasopressin initiation was associated with a lower incidence of RRT as compared to later vasopressin initiation, though we did find that earlier initiation of vasopressin was associated with lower volume administration and earlier shock reversal. Further investigations are needed to determine the circumstances under which initiating vasopressin would confer nephroprotective effects.
BACKGROUND: Acute kidney injury (AKI) requiring renal replacement therapy (RRT) is a common complication of septic shock. Earlier vasopressin initiation may improve renal outcomes. We hypothesized that earlier vasopressin initiation would improve renal outcomes as compared to later vasopressin initiation.
METHODS: This is a single-center historical cohort study at an academic tertiary center. An exposure window was defined from shock onset (T0) to 24 h post-shock (T1). Patients were stratified to early (<4 h post-T0) or late (≥4-24 h post-T0) vasopressin initiation groups. Multivariable Cox proportional hazards regression models were fit to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for time to incident RRT over 7 days following T1.
RESULTS: Of the 674 patients included, 327 (49%) initiated vasopressin early. Baseline characteristics were similar between both groups. Risk of incident RRT after T1 was not significantly different between groups (late versus early: HR = 1.16; 95% CI [0.76, 1.75]; P = 0.49). However, the early group demonstrated higher rates of shock reversal within 24 h of T0 compared to the late vasopressin group (42.2% versus 29.7%, P < 0.001). There were no significant differences in mortality or need for mechanical ventilation.
CONCLUSION: To our knowledge, this is the first retrospective analysis to compare early versus late vasopressin initiation in septic shock while using defined temporal thresholds and a delineated exposure window. Within the temporal definitions used in this retrospective analysis, we did not find that earlier vasopressin initiation was associated with a lower incidence of RRT as compared to later vasopressin initiation, though we did find that earlier initiation of vasopressin was associated with lower volume administration and earlier shock reversal. Further investigations are needed to determine the circumstances under which initiating vasopressin would confer nephroprotective effects.