ISSN:
1432-2013
Keywords:
Acid-base balance
;
pHa
;
Bicarbonate
;
Thermal polypnea
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract This study was undertaken to determine if the decrease in $$Pa_{CO_2 }$$ and the concomitant increase in pHa seen during acute (less than 24 h) hyperthermia in all mammals was modified when the hyperthermia was maintained for periods longer than 1 day. Catheters were placed in the descending aortas of anesthetized ewes (pentobarbital, 30 mg/kg, i.v.). After recovery from the surgery, arterial blood samples were drawn daily during a 7 day control period and an 8 day period of continuous hyperthermia. In all animals $$Pa_{CO_2 }$$ decreased and remained low during the entire hyperthermic period. $$Pa_{CO_2 }$$ (torr) andT r (°C) were inversely correlated by the equation: $$Pa_{CO_2 }$$ = −6.08T r+267.8 (r=0.84). There was an initial alkalosis with hyperthermia, however pH tended to decrease after the fifth day of hyperthermia. Calculated bicarbonate decreased during hyperthermia. The evidence suggested that when body temperature was increased in sheep, $$Pa_{CO_2 }$$ was maintained at a lower value. The low $$Pa_{CO_2 }$$ value was maintained independent of changes in pHa.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00584430
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