Wilderness & environmental medicine
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Portable emergency ventilators are commonly used in the prehospital setting in the transport of critically ill patients in hypobaric environments. The aim of our trial was to evaluate the influence on minute ventilation and blood gas analysis of moderate altitude (3000 m) compared to 171 m in healthy volunteers during mechanical ventilation with the Draeger Oxylog ventilator. ⋯ PaCO2 at 3000 m altitude decreased by 9.0% in the air mix mode and by 12.8% in the no air mix mode. These changes are of sufficient magnitude and importance to require monitoring of minute volume to prevent barotrauma or volume-related trauma and to monitor oxygenation by pulse oximetry during emergency mechanical ventilation at moderate altitude.
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Wilderness Environ Med · Aug 1995
Serum potassium concentration as a predictor of resuscitation outcome in hypothermic cardiac arrest.
The purpose of this study was to determine whether serum potassium concentration (SK) can predict resuscitation outcome in a canine model of severe hypothermic cardiac arrest. Fifteen adult mongrel anesthetized dogs were immersed to the neck in a 4 degrees C water bath and ventilated with room air, with ventilation halved at 45 min and stopped at 90 min. After cardiac arrest, 14 of the dogs were kept in the water bath for periods of 2-7 h, and another was held in arrest for 13 h. ⋯ SK after 10 min of CPR was higher in some animals with ROSC (9.6 and 11.1) than in others which did not have ROSC (4.5 and 7.9). We conclude that very high SK following prolonged hypothermic cardiac arrest may be suggestive of an inability to resuscitate. However, SK after both prolonged hypothermic cardiac arrest and a brief period of CPR is not a good predictor of resuscitation using cardiopulmonary bypass rewarming in an animal model.