Anesthesia and analgesia
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Anesthesia and analgesia · Oct 1996
Randomized Controlled Trial Comparative Study Clinical TrialClonidine increases the sweating threshold, but does not reduce the gain of sweating.
We tested the hypothesis that clonidine produces a dose-dependent increase in the sweating threshold but does not reduce the gain of sweating. Six healthy male volunteers were evaluated, each on three separate days in random order. In one, saline was administered; in another, a 2-micrograms/kg bolus of clonidine was followed by an infusion at 2 micrograms.kg-1.h-1, and on a third day, a 4-micrograms/kg bolus was followed by an infusion at 4 micrograms.kg-1.h-1. ⋯ These data suggest that the antishivering effect of clonidine results from central thermoregulatory inhibition rather than a specific peripheral action on thermogenic muscular activity. Unlike other sedatives and anesthetics, the concentration-dependence of clonidine demonstrates a ceiling beyond which the administration of an additional drug fails to enhance the effect, suggesting that the thermoregulatory effect of clonidine may be limited, even at high plasma concentrations. The gain of sweating was well preserved indicating that this response remains effective in the presence of sedatives and anesthetics.
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Anesthesia and analgesia · Oct 1996
Randomized Controlled Trial Comparative Study Clinical TrialAwakening, clinical recovery, and psychomotor effects after desflurane and propofol anesthesia.
We compared postanesthetic and residual recovery of desflurane versus propofol anesthesia. Twenty volunteers were anesthetized for 1 h at 1-wk intervals with either propofol (induction) plus desflurane (1.25 minimum alveolar anesthetic concentration) in O2 (PD), propofol plus desflurane in N2O-O2 (PDN), propofol plus propofol infusion with N2O-O2 (PPN), or desflurane (induction) plus desflurane in O2 (DD). Awakening and clinical recovery were measured. ⋯ At 1 h after anesthesia, the subjects given desflurane for maintenance (PD, PDN, and DD) performed significantly (P < 0.05-0.01) better in several psychomotor tests compared with those whose anesthesia was maintained with propofol (PPN). However, subjects met criteria for home readiness as fast after PPN as after PDN anesthesia (mean times +/- SE until fitness for discharge were 126 +/- 20, 81 +/- 14, 70 +/- 7, and 106 +/- 14 min after PD, PDN, PPN, and DD, respectively). Awakening and early psychomotor recovery for as long as 1 h after anesthesia is faster after desflurane than after propofol, but there was no difference in time to home readiness or in residual effects thereafter between propofol and desflurane with N2O in O2.
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Anesthesia and analgesia · Oct 1996
Randomized Controlled Trial Comparative Study Clinical TrialTranscutaneous cranial electrical stimulation (Limoge's currents) decreases early buprenorphine analgesic requirements after abdominal surgery.
Transcutaneous cranial electrical stimulation with Limoge's currents (TCES) consists of high frequency, low intensity currents which decreased anesthetic requirements during elective surgery. This action is likely to be mediated by the release of central endogenous opioids. In the present study, we hypothesized that TCES applied intraoperatively may decrease early postoperative narcotic requirements. ⋯ Intraoperative isoflurane anesthetic requirements, as well as hourly postoperative scores for pain and sedation, were the same for the two groups. These data indicate that TCES reduces narcotic requirements for early postoperative analgesia. This technique might have potential to facilitate early postoperative analgesia in patients undergoing elective abdominal surgery.
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Anesthesia and analgesia · Oct 1996
Comparative StudySmall-volume resuscitation using hypertonic saline improves organ perfusion in burned rats.
Resuscitation using small volumes (3-5 mL/kg) of 7.5% hypertonic saline (HTS) is effective for hemorrhagic shock. Whether HTS is beneficial for the initial resuscitation of burn injury is not clear. We compared the hemodynamic effects of HTS versus lactated Ringer's solution (LR) and examined organ tissue perfusion during burn resuscitation (R). ⋯ Resuscitation using HTS was associated with rapid improvement in organ tissue perfusion in anesthetized rats subjected to burn injury. In comparison to LR, greater increases in blood flows to the heart, kidney, liver, and testis were observed with HTS. The results suggest that significant improvement in blood flow distribution can be achieved using HTS at less than one fifth the volume of LR for the initial treatment of burn shock.
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Anesthesia and analgesia · Oct 1996
Randomized Controlled Trial Comparative Study Clinical TrialPostoperative analgesia after peripheral nerve block for podiatric surgery: clinical efficacy and chemical stability of lidocaine alone versus lidocaine plus clonidine.
Postoperative analgesia may be prolonged by the addition of clonidine to local anesthetic solutions used for regional anesthesia. The purpose of this study was to test this hypothesis in a clinical trial of patients undergoing podiatric surgery. The study design was prospective, double-blinded, and randomized. ⋯ Group C20 results suggested no statistically significant improvement over plain lidocaine. One patient in Group C20 experienced significant hypotension postoperatively. pH determinations and chemical analysis by capillary electrophoresis showed no significant change in composition of the solutions when clonidine was mixed with lidocaine and stored at 4 degrees C for 1 wk. Compared to 1.73% lidocaine, combining clonidine (10 micrograms/mL) with lidocaine for local anesthetic block for foot surgery significantly increases the duration and quality of postoperative analgesia.