Anesthesia and analgesia
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Anesthesia and analgesia · Aug 1997
Randomized Controlled Trial Clinical TrialThe dose-response pharmacology of intrathecal sufentanil in female volunteers.
The pharmacologic effects of intrathecal sufentanil (ITS) beyond what is clinically administered (10 microg) are not known. We observed 18 healthy, young, adult female volunteers who received 12.5, 25, or 50 microg of ITS in a randomized, double-blind fashion for 11 h. Analgesia was assessed by pressure algometry at the tibia. ⋯ Serum sufentanil concentrations were related to ITS dose in a statistically significant manner, reached clinically significant concentrations, and followed a time course similar to analgesia and measures of respiratory depression. However, there was no significant increase in measured analgesia associated with the increases in serum sufentanil concentrations. We conclude that in our volunteer model of lower extremity pain, administering ITS in doses larger than 12.5 microg does not improve the speed of onset, magnitude, or duration of analgesia and only causes dose-related increases in serum sufentanil concentrations, which may augment respiratory depression.
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Anesthesia and analgesia · Aug 1997
Randomized Controlled Trial Comparative Study Clinical TrialA randomized, double-blind, dose-response comparison of epidural fentanyl versus sufentanil analgesia after cesarean section.
This study was designed to determine and compare the dose-response characteristics, speed of onset, and relative potency of single-dose epidural fentanyl (F) and sufentanil (S) for postoperative pain relief. Eighty women undergoing cesarean section (C/S) with epidural 2% lidocaine with epinephrine (1:200,000) were randomly assigned to receive double-blind epidural administration of F (25, 50, 100, or 200 microg) or S (5, 10, 20, or 30 microg) (n = 10 per group) upon complaint of pain postoperatively. Visual analog scales (VAS, 0-100 mm) were used to assess pain and sedation at baseline; at 3, 6, 9, 12, 15, 20, 25, 30, 45, and 60 min; and every 30 min until further analgesia was requested. ⋯ The 50% and 95% effective dose values for each opioid to achieve a VAS score <10 mm were F 33 microg and 92 microg and S 6.7 microg and 17.5 microg. There were no differences among groups in sedation scores or side effects. Our data suggest that the relative analgesic potency of epidural S:F is approximately 5 and that there are no differences between the opioids in the onset, duration, and effectiveness of analgesia when equianalgesic doses are administered postoperatively after lidocaine anesthesia for C/S.
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Anesthesia and analgesia · Aug 1997
Randomized Controlled Trial Comparative Study Clinical TrialThe arterial blood propofol concentration preventing movement in 50% of healthy women after skin incision.
To target appropriate drug concentrations and to facilitate comparisons between drugs, the potency of propofol must be firmly established. We therefore determined the arterial blood propofol concentration preventing movement in 50% of patients after skin incision and the ability of arterial blood pressure and heart rate to predict movement after incision. Fifteen healthy women scheduled for breast surgery were randomly assigned to computer-targeted propofol blood concentrations. ⋯ The MABP50 and MABP95 values were 63 +/- 4 mm Hg and 43 mm Hg, respectively. Heart rate did not differ significantly in patients who moved and who did not move. Propofol blood concentrations required to prevent movement in most patients resulted in significant arterial hypotension.
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Anesthesia and analgesia · Aug 1997
Randomized Controlled Trial Comparative Study Clinical TrialThe effects of epidural fentanyl on hemodynamic responses during emergence from isoflurane anesthesia and tracheal extubation: a comparison with intravenous fentanyl.
To investigate the effects of epidural fentanyl infusion on hemodynamic responses to recovery of consciousness and tracheal extubation, we studied 50 unpremedicated patients scheduled for abdominal hysterectomy. All patients underwent epidural catheterization and blind infusion of placebo and study drug. Patients were assigned randomly to three groups: Group I received epidural and intravenous (i.v.) bolus injections and infusion of saline at the rate of 0.2 mL x kg(-1) x h(-1); Group II received an i.v. injection of fentanyl 2 microg/kg for 30 s followed by 25 ng x kg(-1) x min(-1), and Group III received epidural injection and infusion using the same administration regimen as Group II. ⋯ The incidence of coughing during and after extubation was also lower with Group III. Suppression of respiratory rate prior to tracheal extubation was similar in the two groups receiving fentanyl. These findings suggest that the significant reduction in arterial pressures responses to tracheal extubation due to epidural fentanyl infusion may arise from more suppression of cough reflex than i.v. fentanyl infusion, which could be provided by the spinal action of epidural fentanyl as well as the supraspinal action.