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
ReviewCerebral blood flow and metabolism during cardiopulmonary bypass.
Although much has been learned about cerebral physiology during CPB in the past decade, the role of alterations in CBF and CMRO2 during CPB and the unfortunately common occurrence of neuropsychologic injury still is understood incompletely. It is apparent that during CPB temperature, anesthetic depth, CMRO2, and PaCO2 are the major factors that effect CBF. The systemic pressure, pump flow, and flow character (pulsatile versus nonpulsatile) have little influence on CBF within the bounds of usual clinical practice. ⋯ It must be emphasized that not the absolute level of CBF, but the appropriateness of oxygen delivery to demand is paramount. However, the assumption that the control of cerebral oxygen and nutrient supply and demand will prevent neurologic injury during CPB is simplistic. A better understanding of CBF, CMRO2, autoregulation and mechanism(s) of cerebral injury during CPB has lead to a scientific basis for many of the decisions made regarding extracorporeal perfusion.
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Anesthesia and analgesia · Apr 1993
Randomized Controlled Trial Comparative Study Clinical TrialPropofol infusion and the incidence of emesis in pediatric outpatient strabismus surgery.
A prospective, randomized, double-blind study was conducted to examine the effect of a propofol infusion on the incidence of postoperative emesis in children undergoing outpatient strabismus surgery. Seventy-eight children, aged 3-12 yr, were allocated randomly to receive either nitrous oxide and halothane or nitrous oxide and a propofol infusion for the maintenance of anesthesia. ⋯ In children who received no opioids postoperatively, the incidence of vomiting in the first 24 h was 71% in the halothane group and 24% in the propofol group; this difference was also significant (P = 0.001). We conclude that propofol was effective in reducing the incidence of postoperative emesis in pediatric outpatient strabismus surgery.
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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)