Association between dose of catecholamines and markers of organ injury early after out-of-hospital cardiac arrest.

BACKGROUND: Catecholamines are recommended as first-line drugs to treat hemodynamic instability after out-of-hospital cardiac arrest (OHCA). The benefit-to-risk ratio of catecholamines is dose dependent, however, their effect on metabolism and organ function early after OHCA has not been investigated. METHODS: The Post-Cardiac Arrest Syndrome (PCAS) pilot study was a prospective, observational, multicenter study. The primary outcomes of this analysis were association between norepinephrine/cumulative catecholamines doses and neuron specific enolase (NSE)/lactate concentration over the first 72 hours after resuscitation. The association was adjusted for proven OHCA mortality predictors and verified with propensity score matching (PSM). RESULTS: Overall 148 consecutive OHCA patients; aged 18-91 (62.9 ± 15.27), 41 (27.7%) being female, were included. Increasing norepinephrine and cumulative catecholamines doses were significantly associated with higher NSE concentration on admission (r = 0.477, p < 0.001; r = 0.418, p < 0.001) and at 24 hours after OHCA (r = 0.339, p < 0.01; r = 0.441, p < 0.001) as well as with higher lactate concentration on admission (r = 0.404, p < 0.001; r = 0.280, p < 0.01), at 24 hours (r = 0.476, p < 0.00; r = 0.487, p < 0.001) and 48 hours (r = 0.433, p < 0.01; r = 0.318, p = 0.01) after OHCA. The associations remained significant up to 48 hours in non-survivors after PSM. CONCLUSIONS: Increasing the dose of catecholamines is associated with higher lactate and NSE concentration, which may suggest their importance for tissue oxygen delivery, anaerobic metabolism, and organ function early after OHCA.