Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

Sodium nitroprusside-enhanced cardiopulmonary resuscitation improves resuscitation rates after prolonged untreated cardiac arrest in two porcine models*

Schultz, Jason C. MD; Segal, Nicolas MD; Caldwell, Emily RN; Kolbeck, James MD; McKnite, Scott BS; Lebedoff, Nick BS; Zviman, Menekhem PhD; Aufderheide, Tom P. MD; Yannopoulos, Demetris MD

doi: 10.1097/CCM.0b013e31822668ba
Laboratory Investigations
Buy

Objective: Sodium nitroprusside-enhanced cardiopulmonary resuscitation consists of active compression-decompression, an impedance threshold device, abdominal binding, and large intravenous doses of sodium nitroprusside. We hypothesize that sodium nitroprusside-enhanced cardiopulmonary resuscitation will significantly increase carotid blood flow and return of spontaneous circulation compared to standard cardiopulmonary resuscitation after prolonged ventricular fibrillation and pulseless electrical activity cardiac arrest.

Design: Prospective randomized animal study.

Setting: Hennepin County Medical Center Animal Laboratory.

Subjects: Forty Yorkshire female farm-bred pigs weighing 32 ± 2 kg.

Interventions: In protocol A, 24 isoflurane-anesthetized pigs underwent 15 mins of untreated ventricular fibrillation and were subsequently randomized to receive standard cardiopulmonary resuscitation (n = 6), active compression-decompression cardiopulmonary resuscitation + impedance threshold device (n = 6), or sodium nitroprusside-enhanced cardiopulmonary resuscitation (n = 12) for up to 15 mins. First defibrillation was attempted at minute 6 of cardiopulmonary resuscitation. In protocol B, a separate group of 16 pigs underwent 10 mins of untreated ventricular fibrillation followed by 3 mins of chest compression only cardiopulmonary resuscitation followed by countershock-induced pulseless electrical activity, after which animals were randomized to standard cardiopulmonary resuscitation (n = 8) or sodium nitroprusside-enhanced cardiopulmonary resuscitation (n = 8).

Measurements and Main Results: The primary end point was carotid blood flow during cardiopulmonary resuscitation and return of spontaneous circulation. Secondary end points included end-tidal CO2 as well as coronary and cerebral perfusion pressure. After prolonged untreated ventricular fibrillation, sodium nitroprusside-enhanced cardiopulmonary resuscitation demonstrated superior rates of return of spontaneous circulation when compared to standard cardiopulmonary resuscitation and active compression-decompression cardiopulmonary resuscitation + impedance threshold device (12 of 12, 0 of 6, and 0 of 6 respectively, p < .01). In animals with pulseless electrical activity, sodium nitroprusside-enhanced cardiopulmonary resuscitation increased return of spontaneous circulation rates when compared to standard cardiopulmonary resuscitation. In both groups, carotid blood flow, coronary perfusion pressure, cerebral perfusion pressure, and end-tidal CO2 were increased with sodium nitroprusside-enhanced cardiopulmonary resuscitation.

Conclusions: In pigs, sodium nitroprusside-enhanced cardiopulmonary resuscitation significantly increased return of spontaneous circulation rates, as well as carotid blood flow and end-tidal CO2, when compared to standard cardiopulmonary resuscitation or active compression-decompression cardiopulmonary resuscitation + impedance threshold device.

From the Department of Medicine, Division of Cardiology (JCS, NS, EC, JK, SM, NL, DY), University of Minnesota, Minneapolis, MN; the Department of Medicine (MZ), Johns Hopkins University, Baltimore, MD; and the Department of Emergency Medicine (TPA), Medical College of Wisconsin, Milwaukee, WI.

Supported, in part, by an Institutional, Division of Cardiology grant at the University of Minnesota, and NIH grant R01 HL108926–01 to Dr. Yannopoulos.

Preliminary data from this manuscript were reported in the Resuscitation Science Symposium in Chicago 2010.

The authors have not disclosed any potential conflicts of interest.

For information regarding this article, E-mail: yanno001@umn.edu

© 2011 by the Society of Critical Care Medicine and Lippincott Williams & Wilkins