ABSTRACT
The respiratory effects of lorazepam (a 1, 4 benzodiazepine) were studied using a modified Read rebreathing technique in healthy adult males about to undergo elective surgery. Lorazepam 0.05 mg/kg (IV) produced an increase in slope and a shift to the left of the CO2 response curve. These effects were also detectable but of smaller magnitude when the same lorazepam dose (IV) was given with meperidine (IV). End-expiratory CO2 (PeCO2), which was significantly elevated in all drug groups, is not a sensitive indicator of either the time course or the degree of respiratory depression.
Subject(s)
Lorazepam/pharmacology , Meperidine/pharmacology , Respiration/drug effects , Adult , Drug Combinations , Humans , Injections, Intravenous , Lorazepam/administration & dosage , Male , Meperidine/administration & dosageSubject(s)
Affective Symptoms/psychology , Intellectual Disability/psychology , Learning Disabilities/psychology , Adolescent , Child , Female , Humans , Learning , MaleABSTRACT
Neuromuscular blockades induced by clindamycin alone and with d-tubocurarine or pancuronium were examined in the in-vitro guinea pig lumbrical muscle-nerve preparation. Clindamycin, 80-240 mug/ml, initially increased twitch tension. With higher concentrations (180-240 mug/ml) twitch tension subsequently decreased. With 15 to 20 per cent depression of twitch tension by clindamycin, neostigmine (5-20 ng/ml) or calcium (81 mug/ml) slightly but not completely antagonized the blockade. Clindamycin, 40 mug/ml, a dose that did not depress twitch tension, potentiated d-tubocurarine- or pancuronium-induced neuromuscular bloackade. Plasma concentrations of clindamycin of 10-40 mug/ml were recommended for treating serious infections. The authors conclude that the administration of clindamycin may augment nondepolarizing blockade in man, and antagonism by neostigmine and calcium may be incomplete.
Subject(s)
Clindamycin/pharmacology , Neuromuscular Blocking Agents/pharmacology , Adjuvants, Anesthesia , Animals , Calcium/pharmacology , Clindamycin/administration & dosage , Guinea Pigs , In Vitro Techniques , Neostigmine/pharmacology , Neuromuscular Junction/drug effects , Pancuronium/pharmacology , Tubocurarine/pharmacologyABSTRACT
Either fentanyl or Innovar (fentanyl, 0.05 mg/ml, and droperidol 2.5 mg/ml) was administered to supplement nitrous oxide anesthesia for operations on 29 patients. Both fentanyl and Innovar depressed the slope of the rebreathing CO2 response curve during operation to 42 per cent +/- 6 (mean of all intraoperative values, +/- SE) of the awake control value. Following the last injection of drug but with continuation of operation, the slope increased such that it was 77 per cent +/- 8 of control on the patients' arrival in the recovery room. The slope continued to increase to a peak of 103 per cent +/- 9 of control. Soon therafter respiratory depression recurred, as indicated by a decline in the slope to 55 per cent +/- 5 of control, with a subsequent gradual return to 85 per cent +/- 8 of control 230 minutes after the last injection. This biphasic response occurred in 90 per cent (26 of 29) of the patients treated either with fentanyl alone or with Innovar. Full recovery appeared to be more rapid with Innovar than with fentanyl alone. Droperidol did not augment and may have attenuated fentanyl-induced respiratory-depression.
