Percutaneous transtracheal ventilation in a canine shock model with an open thorax

This study evaluates the effectiveness of percutaneous transtracheal ventilation (PTV) in a canine shock model. Five mongrel dogs (25 to 35 kg), splenectomized two weeks prior to study, were anesthetized (pentobarbital, 22 mg/kg) and bled to and sustained at a mean arterial pressure (MAP) of 20 mm Hg for 60 minutes. Ringer's lactate was infused and the descending thoracic aorta was cross-clamped. Simultaneously, PTV was begun with 60% O2 through the cricothyroid membrane. Hemodynamic measurements and arterial blood gases were obtained at 0, 5, 15, and 30 minutes following the initiation of PTV. Orotracheal ventilation was then instituted in place of PTV and continued for 30 minutes, and measurements were repeated. Auto-transfusion was also begun at this time. During PTV, PO2 and PCO2 were adequate in all dogs at each interval. We conclude that PTV provides effective oxygenation and ventilation in dogs subjected to profound shock, thoractomy, and thoracic aortic cross-clamp.