Biomedical subjects
Publications and source records attributed to D F Aultman.
We report a case of bowel injury as a result of an isolated gunshot wound to the scrotum. Our experience with penetrating scrotal trauma reveals a high rate of associated injuries, the most common being trauma to the soft tissue of the thigh. Our case emphasizes the importance of a thorough preoperative and operative evaluation of patients with penetrating scrotal trauma.
The effects of fentanyl, nitrous oxide, and their combination on myocardial contractility were investigated in the papillary muscle preparation perfused by a donor dog. With a conscious donor, fentanyl infused directly into the arterial blood perfusing the papillary muscle produced a dose-related depression of developed tension. However, blood concentrations of fentanyl required to obtain the depression were in the range of 30-120 micrograms/ml. The ED50 for fentanyl for suppression of papillary muscle contractility was 89 +/- 9 micrograms/ml. When the donor dog was given nitrous oxide (N2O,80% and O2,20%), the developed tension of the papillary muscle decreased 25 +/- 5%. Fentanyl administered during nitrous oxide anesthesia caused a decrease in developed tension that was not significantly different from that obtained without N2O anesthesia (18 +/- 4% vs 13 +/- 4% for 30 micrograms/ml, and 61 +/- 5% vs 58 +/- 4% for 100 micrograms/ml). The results suggest that fentanyl produces a direct negative inotropic effect only in concentrations that are 2-3 orders of magnitude higher than its blood concentrations in fentanyl-induced anesthesia. When fentanyl and nitrous oxide are used together their interaction is not significantly different from additive.
In experiments on isolated rat heart perfused by the Langendorff method, the effect of halothane, isoflurane, enflurane, and diethyl ether on myocardial oxidation-reduction status was evaluated with reduced nicotinamide adenine dinucleotide (NADH) fluorometry. All inhaled anesthetics studied caused a dose-dependent increase in NADH fluorescence. Concentrations of anesthetics necessary to produce 10% of the maximal increase in NADH fluorescence caused by anoxia were 1.1% for halothane, 1.6% for isoflurane, 2.6% for enflurane, and 6.8% for diethyl ether (all concentrations are different from each other at P less than 0.05 level, n = 24). These findings indicate that the order of potency with regard to the effect of the agent on NADH paralleled their potencies as general anesthetics. The deterioration in myocardial oxidation-reduction status probably is related to the ability of the anesthetic agents to inhibit the electron transport chain in mitochondria.
The effects of etomidate and thiopental on myocardial contractility were compared in 10 experiments on isolated papillary muscle preparation perfused by a conscious donor dog. Equianesthetic doses of etomidate (1.4 mg/kg) and thiopental (15.5 mg/kg) were determined separately in conscious dogs. Tension developed by the papillary muscle decreased significantly less after etomidate (17 +/- 2%) than after thiopental (33 +/- 3%) (P less than 0.002) when injected intravenously in equianesthetic doses in donor dogs. When added to arterial blood perfusing the papillary muscle, etomidate had 4-5 times more negative inotropic effect than thiopental. At the same time, the anesthetic potency of etomidate was approximately 11 times greater than that of thiopental. We conclude that both etomidate and thiopental produce a dose-dependent direct negative inotropic effect but that in equianesthetic doses, etomidate causes less pronounced depression of myocardial contractility than thiopental.