RESPIRATORY ALKALOSIS DURING ANESTHESIA II. INFLUENCE ON SURVIVAL

¹ From the Department of Pharmacology of the University of Wisconsin, Madison

Permanent survival occurred in seventeen of twenty barbitalized dogs subjected to excessive mechanical hyperventilation sufficient to produce a 40 to 80 per cent reduction in the CO₂ content of arterial blood for from one to fifteen hours. Death of two of three non-survivors could be accounted for by mechanical injury to the lung. Three animals survived two periods of hyperventilation. Hemoglobinemia and hemoglobinuria occurred in the majority of these experiments. One unanesthetized dog (local anesthesia only) survived one hundred forty minutes of hyperventilation, the final pressure of CO₂ in arterial plasma being 9 mm. Fatal respiratory failure following hyperventilation did not occur, the period of apnea ranging from fifteen to two hundred seconds.