Continuous passive oxygen insufflation results in a similar outcome to positive pressure ventilation in a swine model of out-of-hospital ventricular fibrillation.
BACKGROUND
The deleterious effects of positive pressure ventilation may be prevented by substituting passive oxygen insufflation during advanced cardiac life support (ACLS) cardiopulmonary resuscitation (CPR).


METHODS
We compared 24-h neurologically normal survival among three different ventilation scenarios for ACLS in a realistic swine model of out-of-hospital prolonged ventricular fibrillation (VF) cardiac arrest. No bystander CPR was provided during the first 8 min of untreated VF before the simulated arrival of an emergency medical system (EMS). Thirty-six swine were randomly assigned to one of three experimental groups. Group I (standard ventilation) was mechanically ventilated at 10 respirations per minute (RPM) at a tidal volume (TV) of 10 ml/kg with 100% oxygen. Group II (hyperventilation) was ventilated at 35 RPM at a TV of 20 ml/kg with 100% oxygen. In Group III (insufflation) animals, a nasal cannula was placed in the oropharynx to administer oxygen continuously at 10 l/min.


RESULTS
There was no significant difference in the 24h neurologically normal survival among groups (standard: 2/12, hyperventilation: 2/12, insufflation: 4/12; p=.53).


CONCLUSIONS
Passive insufflation may be an acceptable alternative to the currently recommended positive pressure ventilation during resuscitation efforts for out-of-hospital VF cardiac arrest. Potential advantages of this technique include: (1) easier to teach, (2) easier to administer, (3) prevention of the adverse effects of positive pressure ventilation and (4) allows EMS personnel to concentrate upon other critically important duties.
Hayes
Melinda M
MM
Department of Anesthesiology, University of Arizona, College of Medicine, Sarver Heart Center, Tucson, AZ 85724, USA.
Ewy
Gordon A
GA
Anavy
Nathan D
ND
Hilwig
Ronald W
RW
Sanders
Arthur B
AB
Berg
Robert A
RA
Otto
Charles W
CW
Kern
Karl B
KB
D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D016009:Chi-Square Distribution; D004195:Disease Models, Animal; D005260:Female; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D011175:Positive-Pressure Respiration; D012372:ROC Curve; D011897:Random Allocation; D015996:Survival Rate; D013552:Swine; D013990:Tidal Volume; D014693:Ventricular Fibrillation / Q000503:physiopathology / Q000628:therapy*