title: The effects of an automatic, low pressure and constant flow ventilation device versus manual ventilation during cardiovascular resuscitation in a porcine model of cardiac arrest.
abstract: BACKGROUND
  Cardiac arrest is an important cause of mortality. Cardiopulmonary resuscitation (CPR) improves survival, however, delivery of effective CPR can be challenging and combining effective chest compressions with ventilation, while avoiding over-ventilation is difficult. We hypothesized that ventilation with a pneumatically powered, automatic ventilator (Oxylator(®)) can provide adequate ventilation in a model of cardiac arrest and improve the consistency of ventilations during CPR.
  
  
  RESULTS
  Twelve pigs (∼40 kg, either sex) underwent 3 episodes each of cardiac arrest and resuscitation consisting of 30s of untreated ventricular fibrillation, followed by 5 min of CPR, defibrillation, and ∼30 min of recovery. During CPR in each episode, pigs were ventilated in 1 of 3 ways in random balanced order: manual ventilation using AMBU bag (12 breaths/min), low pressure Oxylator(®) (maximum airway pressure 15 cm H2O with 20 L/min constant flow in automatic mode [Ox15/20]), or high pressure Oxylator(®) (maximum airway pressure 20 cm H2O with 30 L/min constant flow in automatic mode [Ox20/30]). During CPR, both Ox15/20 and Ox20/30 resulted in higher levels of positive end expiratory pressure than manual ventilation. Ox15/20 ventilation also resulted in higher arterial pCO2 than manual ventilation. Ox20/30 ventilation yielded higher arterial pO2 and a lower arterial-alveolar gradient than manual ventilation. All pigs were successfully defibrillated, and no measured haemodynamic variables were different between the groups.
  
  
  CONCLUSIONS
  Ventilation with an automatic ventilation device during CPR is feasible and provides adequate ventilation and comparable haemodynamics when compared to manual bag ventilation.
authors: Keenan Research Centre in the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, ON, Canada.
authors: Xudong
authors: X
authors: Hu
authors: Andrew
authors: A
authors: Ramadeen
authors: Gabriel
authors: G
authors: Laurent
authors: Petsy Pui-Sze
authors: PP
authors: So
authors: Ehtesham
authors: E
authors: Baig
authors: Gregory M T
authors: GM
authors: Hare
authors: Paul
authors: P
authors: Dorian
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis / Q000379:methods; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D004554:Electric Countershock / Q000009:adverse effects*; D006323:Heart Arrest / Q000097:blood / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D006439:Hemodynamics; D008955:Models, Cardiovascular; D012121:Respiration, Artificial / Q000009:adverse effects / Q000379:methods; D013552:Swine; D013997:Time Factors; D016896:Treatment Outcome; D012122:Ventilators, Mechanical / Q000592:standards*; D014693:Ventricular Fibrillation / Q000150:complications*
keywords: CPR; Cardiac arrest; Cardiopulmonary resuscitation; Oxylator; Ventricular fibrillation