Abstract 189: Potential Negative Effects of Epinephrine on Carotid Blood Flow and ETCO2 During Active Compression-Decompression CPR Utilizing an Impedance Threshold Device
Objectives: This study examined the effects of IV epinephrine administration on carotid blood flow and end tidal CO2 (ETCO2) production of a swine undergoing active compression-decompression CPR with an impedance threshold device (ACD-CPR + ITD).
Methods: Six female swine (32±1Kg) were anesthetized, intubated and mechanically ventilated. Intracranial, thoracic aorta and right atrial pressures were recorded via indwelling catheters. Carotid blood flow (CBF) was recorded via Doppler. ETC02, Sp02 and EKG were monitored. V-fib was induced and went untreated for 6 minutes. 3 minutes each of standard CPR (STD), STD-CPR+ITD and ACD-CPR+ITD was preformed. At minute 9 of the resuscitation, 40µg/Kg of IV Epinephrine was administered and ACD-CPR+ITD was continued for 1 minute. Statistical analysis was performed with a Paired t test.
Results: Aortic pressure and calculated cerebral and carotid perfusion pressures increased from STD < STD+ITD < ACD-CPR < ACD-CPR+ITD (p=<.001). Epinepherine administered during ACD-CPR+ITD signficantly increased mean aortic (29±5vs42±12, p=0.01) cerebral (12±5 vs 22±10, p=0.01), and coronary perfusion pressures (8±7 vs 17±4, p=0.02); however, mean CBF and ETCO2 decreased (respectively 29±15 vs 14±7.0, p=0.03; 20±7 vs 18±6, p=0.04).
Conclusions: The administration of epinepherine during ACD-CPR+ITD signficantly increased markers of macrocirculation, while significantly decreasing ETCO2, a proxy for organ perfusion. While the calculated cerebral perfusion pressures increased, the directly measured CBF decreased. This calls into question the ability of calculated perfusion pressures to accurately reflect blood flow and oxygen delivery to end organs.
- © 2011 by American Heart Association, Inc.