NEUROLEPTANALGESICS: A COMPARISON OF THE CARDIOVASCULAR, RESPIRATORY AND METABOLIC EFFECTS OF INNOVAN AND THIOPENTONE PLUS METHOTRIMEPRAZINE

Crossover experiments were carried out in dogs with a 50:1 mixture of dehydrobenzperidol and phentanyl (Innovan) and a 40:1 mixture of thiopentone and methotrimeprazine to determine their efficacy as anaesthetics, and their effect on blood pressure, heart rate, acid base balance, blood sugar, serum potassium, blood urea nitrogen and blood transaminases. Both mixtures, when used with a 2:1 nitrous oxide and oxygen mixture and hyperventilation, caused a moderate fall in blood pressure and a lowering of body temperature, a rise in blood sugar and a fall in the serum potassium. Odier measured parameters did not change appreciably. Smooth full recovery from anaesthesia occurred within an hour of responding to a painful stimulus. Respiratory depression was the only noteworthy effect during recovery.