Stephen Slogoff

Neuropsychiatric complications after cardiopulmonary bypass: cerebral protection by a barbiturate.

The authors prospectively investigated the ability of thiopental to decrease neuropsychiatric complications as a consequence of openventricle operations requiring cardiopulmonary bypass. Eighty-nine randomly assigned patients received sufficient thiopental to maintain electroencephalographic silence throughout the period from before atrial cannulation to termination of bypass. These patients received an average of 39.5 mg/kg of thiopental, while 93 control patients received only fentanyl. On the first postoperative day, five thiopental (5.6%) and eight control (8.6%) patients exhibited clinical neuro-psychiatric abnormalities. By the tenth postoperative day, all neuropsychiatric dysfunction had resolved in the thiopental group but persisted in seven (7.5%) control patients (P < 0.025). The incidence of complications was significantly related to calcification of replaced valves, aortic valve replacement, advanced age, and prolonged bypass, but not to low blood pressure during perfusion. The authors believe their data are consistent with embolism as the most important cause of sensory-motor neurologic dysfunction following cardiopulmonary bypass. The data also provide evidence that thiopental in sufficient dosage can reduce the clinical consequences of these events. This is the first demonstration of cerebral protection by a barbiturate in humans.

Clinical experience with subanesthetic ketamine.

Forty thermally injured patients received 150 intramuscular (I.M.) administrations of sub-anesthetic ketamine for debridement and dressing changes. Satisfactory analgesia lasting approximately 15 minutes, complete amnesia, and good operating conditions were achieved. Tolerance to ketamine developed in all patients receiving more than two exposures. Recovery was prompt, with resumption of oral alimentation in approximately 1 hour. Side effects were minimal, and no major complications occurred.

Effect of metoclopramide on gastric fluid volumes in diabetic patients who have fasted before elective surgery

Background: Diabetes-induced gastroparesis is believed to increase fasting gastric fluid volume before elective surgery. Metoclopramide is routinely administered preoperatively to reduce gastric fluid volume in these patients. This study compared nondiabetic controls to non–insulin-dependent and insulin-dependent diabetics to determine the effect of metoclopramide, administered before surgery, on gastric volumes in patients who fasted before surgery. Methods: Control and diabetic patients fasted preoperatively before receiving either placebo or 10 mg intravenous metoclopramide 20 min before induction of anesthesia. After intubation, a gastric tube was placed, and stomach contents were aspirated with volumes compared among the groups. Results: Both groups of diabetic patients were older than the control group, and insulin-dependent patients had a higher incidence of comorbidities compared with the non–insulin-dependent group. Fasting blood sugar and hemoglobin A1C values were higher in both insulin-dependent and non–insulin-dependent patients. Gastric fluid volumes were similar in control, non–insulin-dependent, and insulin-dependent patients (8.0 ± 2.6 vs. 9.6 ± 4.1 vs. 17.7 ± 2.5 ml, respectively). In insulin-dependent diabetic patients, metoclopramide decreased gastric volume compared with placebo treatment (17.7 ± 2.5 vs. 7.8 ± 2.9 ml; P = 0.027). After stratification, a subpopulation of patients with poorly controlled diabetes, regardless of type, were identified to have increased gastric residual volumes. Conclusion: In elective surgical patients who have fasted before surgery, gastric volumes are minimal, even in diabetics with severe neuropathic symptoms. Metoclopramide prophylaxis to reduce gastric volumes seems to be unnecessary unless the patient has a prolonged history of poor blood glucose control.

The Role of Baroreceptors in the Cardiovascular Response to Ketamine

To elucidate the role of the intravascular baroreceptors in the cardiovascular stimulation associated with ketamine anesthesia, an experiment was devised in which the proposed inhibitory baroreceptor mechanism could be effectively blacked by carotid sinus nerve stimulation. In neurologically intact dogs which responded normally to ketamine before and after carotid sinus nerve stimulation, the cardiovascular effect of the drug was not altered by baroreceptor nerve stimulation. In light of this finding and those of other workers, the cardiovascular response to ketamine anesthesia most likely originates at some site in the central nervous system or at a peripheral sensor other than the baroreceptors.

Recovery from neuromuscular blockade after either bolus and prolonged infusions of cisatracurium or rocuronium using either isoflurane or propofol-based anesthetics

We examined the recovery characteristics of cisatracurium or rocuronium after bolus or prolonged infusion under either isoflurane or propofol anesthesia. Sixty patients undergoing neurosurgical procedures of at least 5 h were randomized to receive either isoflurane with fentanyl (Groups 1and 2) or p