PLASMA ELECTROLYTE AND METABOLITE CONCENTRATIONS ASSOCIATED WITH PENTOBARBITAL OR PENTOBARBITAL-PROPOFOL ANESTHESIA DURING 3 WEEKS MECHANICAL VENTILATION AND INTENSIVE-CARE IN DOGS

Propofol and pentobarbital were used for deep sedation during prolonge d mechanical ventilation (3 weeks) and nutritional supplementation in 17 clinically normal dogs in an intensive care setting. Tolerance deve loped to both drugs. Propofol, in combination with pentobarbital, at a n infusion rate of 75 mu g/kg of body weight per minute was preferred, Pentobarbital infusion alone, begun at the rate of 5 to 6 mg.kg(-1).h (-1), was satisfactory, The combination of both drugs provided smooth, stable anesthesia and required minimal interventions by intensive car e unit personnel. Blood gas tensions and electrolyte, parathyroid horm one (PTH), and metabolite concentrations were generally stable through out, unless condition of the dog deteriorated (e.g., infection, pneumo thorax), Hematocrit and red blood cell count decreased with time, like ly attributable principally to multiple blood sample collections. Whit e blood cell count, alkaline phosphatase, phosphate, fibrinogen, chole sterol, and triglyceride values increased with time, in association wi th pentobarbital and the combination of pentobarbital and propofol, So me of these changes appear to have been related to generic responses t o stress and inflammation, some to altered metabolism, and some to the lipid solvent of propofol. The increase in triglyceride concentration was greater when propofol was used. Mortality was 47%, with death occ urring between days 2 and 18.