title: Sodium nitroprusside-enhanced cardiopulmonary resuscitation improves resuscitation rates after prolonged untreated cardiac arrest in two porcine models.
abstract: 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.
  
  
  METHODS
  Prospective randomized animal study.
  
  
  METHODS
  Hennepin County Medical Center Animal Laboratory.
  
  
  METHODS
  Forty Yorkshire female farm-bred pigs weighing 32 ± 2 kg.
  
  
  METHODS
  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).
  
  
  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.
authors: Department of Medicine, Division of Cardiology, University of Minnesota, Minneapolis, MN, USA.
authors: Jason C
authors: JC
authors: Schultz
authors: Nicolas
authors: N
authors: Segal
authors: Emily
authors: E
authors: Caldwell
authors: James
authors: J
authors: Kolbeck
authors: Scott
authors: S
authors: McKnite
authors: Nick
authors: N
authors: Lebedoff
authors: Menekhem
authors: M
authors: Zviman
authors: Tom P
authors: TP
authors: Aufderheide
authors: Demetris
authors: D
authors: Yannopoulos
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D003326:Coronary Circulation / Q000187:drug effects; D004195:Disease Models, Animal; D004452:Echocardiography; D005260:Female; D006323:Heart Arrest / Q000188:drug therapy* / Q000628:therapy; D009599:Nitroprusside / Q000627:therapeutic use*; D013318:Stroke Volume / Q000187:drug effects; D013552:Swine; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D014665:Vasodilator Agents; D009599:Nitroprusside