Anesthesia and analgesia
-
Anesthesia and analgesia · Jul 1997
Randomized Controlled Trial Clinical TrialPreemptive epidural morphine for postoperative pain relief after lumbar laminectomy.
This study was designed to evaluate the efficacy of preemptive epidural morphine for postoperative analgesia after lumbar laminectomy. Thirty ASA physical status I adults undergoing elective lumbar laminectomy under general anesthesia were randomly allocated to one of two groups. Group 1 (study group) received 3 mg epidural morphine preemptively 60 min before surgery, followed by epidural placebo at the end of surgery. ⋯ The demand for supplementary analgesia and postoperative morphine consumption in the preemptive group was significantly lower than that in control group (P < 0.05). Patients in the control group were significantly sedated after 12 h and had a high incidence of nausea and vomiting (P < 0.05). The study shows that preemptive epidural morphine is superior to epidural morphine given postoperatively for pain relief after lumbar laminectomy.
-
Anesthesia and analgesia · Jul 1997
Classification of malignant hyperthermia-equivocal patients by 4-chloro-M-cresol.
To clarify the contracture response to 4-chloro-m-cresol (4-CmC) in malignant hyperthermia (MH) equivocal (MHE) muscle, we studied the effect of cumulative concentrations of 4-CmC. In vitro contracture test (IVCT) was performed in 35 probands according to the European MH test protocol. Surplus muscle bundles were exposed to 4-CmC (25-200 micromol/L), maintaining each concentration for 4 and 8 min. ⋯ Therefore, 4-CmC might reduce the frequency of MHEh diagnosis based on standard halothane-caffeine IVCT. However, since MHE individuals may also represent an aberrant genetic status, with MH causing defects linked to unknown mutations, it is premature to consider 4-CmC as a solution to the diagnostic uncertainty of the true status of MHE probands. Presently, 4-CmC may provide supplementary information for a more precise phenotypic categorization of MHE individuals.
-
Anesthesia and analgesia · Jul 1997
Comparative StudyComparative pharmacokinetics of ropivacaine and bupivacaine in nonpregnant and pregnant ewes.
We determined the pharmacokinetics and protein binding of ropivacaine and bupivacaine after intravenous administration to nonpregnant and pregnant sheep. All animals were in good condition throughout the study. The highest mean total serum drug concentrations were found at the end of infusion. ⋯ In conclusion, the pharmacokinetics of ropivacaine and bupivacaine are altered by ovine pregnancy in a similar way. If these data are applicable to humans, an unintended intravascular injection of either drug could be expected to result in higher total serum concentrations in the pregnant than in the nonpregnant patient, but drug levels would decline at similar rates in both groups of individuals. However, differences between the two drugs, particularly in T(1/2)beta and MRT, may make ropivacaine preferable for use in obstetric anesthesia.
-
Anesthesia and analgesia · Jul 1997
Laryngeal mask airway and the incidence of regurgitation during gynecological laparoscopies.
We studied the incidence of regurgitation in 100 patients undergoing elective gynecological laparoscopies under general anesthesia with intermittent positive pressure ventilation using a laryngeal mask airway (LMA). Patients ingested methylene blue capsules 10-15 min before induction of anesthesia. After induction and insertion of an LMA using the recommended insertion technique, a fiberoptic examination of the larynx was made for traces of dye and to site a pH probe in the bowl of the LMA for continuous monitoring. ⋯ The 95% confidence limit for a true probability of regurgitation in this study is 0.041 or a true rate of regurgitation of less than 4.1%. A larger study would be required to possibly demonstrate a lower incidence of regurgitation. This study confirms the clinical impression that the incidence of regurgitation during laparoscopies with a LMA is extremely low.