Comparison of vasopressin to epinephrine during pediatric in-hospital cardiac arrest: survival and physiologic responsiveness.

Aim: To compare post-epinephrine vasopressin administration versus epinephrine and time to return of spontaneous circulation (ROSC) during pediatric in-hospital cardiac arrest (IHCA), and explore vasopressin's physiologic effects.

Methods: This single-center, retrospective cohort study (2017-2023) compared vasopressin patients who received ≥1 dose of preceding epinephrine and matched epinephrine-only patients based on age, illness category, and preceding epinephrine dosing. Time to ROSC was analyzed using Cox regression. Vasopressor response was defined as ≥5 mmHg increase in diastolic blood pressure (DBP).

Results: Forty-one matched pairs were analyzed. Median CPR duration was 36.5 [IQR 23, 48] minutes; median time to dose was 14.5 [10.8, 19] minutes. ROSC occurred in 10/41 (24%) vasopressin and 15/41 (36%) epinephrine patients (p = 0.34) with no difference in time to ROSC (aHR 0.73 [95% CI: 0.31-1.7]). Vasopressor response occurred in 4/12 (33%) vasopressin and 1/7 (14%) epinephrine patients (p = 0.60). Regression discontinuity analysis demonstrated a change in DBP of +2.3 mmHg after vasopressin (95% CI: -11.4, 16.0) and -5.67 mmHg after epinephrine (-15.13, 3.80).

Conclusion: No significant differences were found in time to ROSC or DBP increase between vasopressin and epinephrine given late during CPR. A subset of vasopressin responders suggests further research on intra-arrest DBP response to vasopressin is needed.

Impact: The use of intra-arrest vasopressin is an understudied topic in pediatric cardiac arrest. This study presents a unique comparison of ongoing epinephrine to vasopressin administration, using dose matching to address the limitations of our current vasopressin use. We present a novel analysis of physiologic response to vasopressin using the change in diastolic blood pressure.