Cooling of Anesthetized Paralyzed Dogs during Hypercapnia and B- Adrenergic Blockade
Abstract
Oxygen consumption, body temperature, plasma lactic acid and ketones were measured in male mongrel dogs, anesthetized, paralyzed, artificially ventilated and cooled in a water bath at 34C. Treatment included inspiration of 10 or 20% CO2, beta adrenergic blockade (propranolol), and beta blockade plus 10% CO2. All treatments resulted in a lower oxygen consumption than controls (P < .05) with the 20% CO2 group showing a greater depression than the other three experimental groups (P < .05). The rate of decline in body temperature was greater while breathing 20% CO2 than room air (P < .05). Beta adrenergic blockade resulted in a drop in lactate levels compared with controls (P < .05), while a further drop occurred with beta blockade plus 10% CO2 (P < .025). Plasma free fatty acids tended to decrease with propranolol or 10% CO2, but the only significant difference detected was an increased downtrend during the first 30 min with the combined treatment. It was concluded that the increased rate of decline of body temperature with hypercapnia was due to decreased heat production primarily by inhibition of the beta-adrenergic calorigenic processes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1971
- Accession Number
- AD0740991
Entities
People
- Stephen M Cain
- William E. Pepelko
Organizations
- United States Air Force School of Aerospace Medicine