Anesthesia and analgesia
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Anesthesia and analgesia · Apr 1993
Randomized Controlled Trial Comparative Study Clinical TrialA-3665, a new short-acting opioid: a comparison with alfentanil.
A-3665 is a new short-acting synthetic opioid of the piperidine class. We conducted a double-blind, escalating dose comparison of A-3665 to alfentanil and placebo. Analgesic efficacy was assessed after the administration of A-3665 in increasing intravenous doses (0.25, 0.5, 1, 2, 4, 8, 16, 32, and 64 micrograms/kg) to nine groups of volunteers. ⋯ There was no significant difference in analgesic potency of A-3665 and alfentanil as measured by tolerance to tibial pressure at 3 min. At the dose of 16 micrograms/kg, both drugs significantly increased pain tolerance to tibial pressure compared with placebo at 3 min, but alfentanil continued to display significant analgesic effect versus placebo and versus A-3665 at 6, 11, and 15 min after injection. A-3665 caused significant respiratory depression at doses of 32 micrograms/kg and 64 micrograms/kg, but alfentanil did not induce significant respiratory depression at the doses tested.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Apr 1993
Randomized Controlled Trial Comparative Study Clinical TrialEvaluation of STAT-CRIT hematocrit determination in comparison to Coulter and centrifuge: the effects of isotonic hemodilution and albumin administration.
The accuracy of the STAT-CRIT hematocrit (hct) was compared to Coulter and centrifuge methods in this study of the interrelationship between non-red cell blood constituents and accuracy of conductivity-based hct measurements. In the first part of the study, blood samples from 31 patients undergoing elective cardiac procedures were analyzed at three times: before induction of anesthesia (Time 1), during the rewarming period of cardiopulmonary bypass (CPB) (Time 2), and after transfusion of all cell-saver blood available after termination of CPB (Time 3). Laboratory evaluation included hct using the Stat-Crit, Coulter, and centrifuge methods, and sodium (Na), potassium (K), chloride (Cl), white blood cell count, total protein (TP), and albumin. ⋯ Blood variables having the most significant effect on the Coulter-Stat-Crit difference (bias) were protein, Cl, and Na. Single regression analysis indicated that a 1-g/dL decrease in TP resulted in an absolute decrease in the hct reading by 1 hct% units. A 10-mmol/L change in either Cl or Na concentration resulted in a change in Stat-Crit accuracy of 3.5% and 2.5%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Apr 1993
Randomized Controlled Trial Clinical TrialProphylactic nitroglycerin infusion during noncardiac surgery does not reduce perioperative ischemia.
We evaluated the impact of prophylactic nitroglycerin on the incidence of perioperative myocardial ischemia in patients with known or suspected coronary artery disease who undergo noncardiac surgery. Our goals were to better define the role of nitroglycerin in the management of high-risk patients and to explore the mechanisms of perioperative myocardial ischemia. Patients were assigned randomly to either a control group (n = 23) or to receive 0.9 micrograms.kg-1.min-1 of intravenous nitroglycerin (n = 22). ⋯ The heart rate associated with the onset of ischemia was greater in the nitroglycerin-treated patients than in the control group. We also found that the occurrence of myocardial ischemia on a preoperative Holter recording was strongly predictive of the subsequent occurrence of perioperative ischemia. In conclusion, the addition of nitroglycerin to standard anesthetic management of these high-risk patients does not measurably reduce perioperative ischemia.