Abstract 2012: Relationship Between Adrenaline Concentration and Postresuscitation Syndrome in Patients with Return of Spontaneous Circulation (ROSC) After Out-of-Hospital Cardiac Arrest

Background Although there is evidence that epinephrine hydrochloride favors initial ROSC, there is a paucity of evidence that it improves survival in humans. The value and safety of the I 2 -adrenergic effects of epinephrine is controversial because they may lead to increase postresuscitation syndrome after ROSC. Few studies have investigated whether adrenaline concentration before epinephrine administration was related to incidence of postresuscitation syndrome. METHODS We did a prospective study of adult patients who achieved ROSC with standard cardiopulmonary resuscitation after out-of-hospital cardiac arrest. Blood samples to measure the adrenaline concentration were taken from a vein. The primary endpoint was neurological outcomes at hospital discharge. RESULTS Of the 274 adult patients with out-of-hospital cardiac arrest, 108(39%) achieved ROSC. The adrenaline levels ranged from 53 to 15,329pg/ml, with a median of 1,545pg/ml, and 25th and 75th percentile values of 707 and 4,486pg/ml, respectively. Of those, 71% (77/108) had an unfavorable neurological outcome and the adrenaline level was higher among such patients than among those with a favorable neurological outcome (a median, 2,016pg/ml vs. 938pg/ml, p=0.048). Moreover, the adrenaline level was higher among patients who died of postresuscitation syndrome within 24 hours of ROSC than among those with survival at 24 hours (a median, 3,290pg/ml vs. 1,343pg/ml, p=0.038). The adrenaline cutoff value of 944pg/ml for unfavorable neurological outcome had an accuracy of 70%. The adjusted odds ratio for the unfavorable neurological outcome after adrenaline cutoff value of 944pg/ml was 8.9 (95% CI, 2.2–35.9; p=0.002). On the other hand, the adrenaline level after epinephrine administration was 28 times as high as that before epinephrine administration (a median, 42,868pg/ml vs. 1,545pg/ml, p CONCLUSIONS In adult patients with ROSC after out-of-hospital cardiac arrest, adrenaline level before epinephrine administration was associated with incidence of postresuscitation syndrome, and the level was extremely increased after epinephrine administration. Epinephrine administration may lead to a severe toxic hyperadrenergic state in postresuscitation period.