Anesthesia and analgesia
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Anesthesia and analgesia · Aug 2004
Comparative StudyDifferential analgesic sensitivity of two distinct neuropathic pain models.
Progressive tactile hypersensitivity (PTH) manifesting after sciatic nerve crush and spared nerve injury (SNI) are two distinct rodent experimental models of neuropathic pain. PTH develops months after recovery from the nerve crush in response to repeated intermittent low-threshold mechanical stimulation of the reinnervated sciatic nerve skin territory and represents a model of stimulus-induced pain. SNI is characterized by an early and sustained increase in stimulus-evoked pain sensitivity in the intact skin territory of the spared sural nerve after sectioning of the two other terminal branches of the sciatic nerve. ⋯ Independent neuropathic pain models show differential sensitivity to analgesic drug treatment. We suggest that this is due to the different mechanisms responsible for the neuropathic pain-related behavior. Multiple models are required, therefore, to study the mechanisms that contribute to neuropathic pain and to predict analgesic efficacy for different components of the neuropathic pain syndrome.
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Anesthesia and analgesia · Aug 2004
Randomized Controlled Trial Clinical TrialThe analgesic effects of gabapentin in monitored anesthesia care for ear-nose-throat surgery.
We investigated the efficacy and safety of gabapentin in rhinoplasty or endoscopic sinus surgery patients. Patients received either oral placebo or gabapentin 1200 mg 1 h before surgery. After standard premedication, 25 patients in each group received propofol, fentanyl, and local anesthesia at the operative site. ⋯ Fentanyl (122 +/- 40 microg versus 148 +/- 42 microg; P < 0.05) and diclofenac (33 +/- 53 mg versus 111 +/- 92 mg; P < 0.001) consumption was smaller and the time to first analgesic request (18 +/- 9 h versus 9 +/- 7 h; P < 0.001) was longer in the gabapentin group. A more frequent incidence of dizziness was found in the gabapentin (versus placebo) group (24% versus 4%, respectively). We conclude that gabapentin provided a significant analgesic benefit for intraoperative and postoperative pain relief in patients undergoing ambulatory rhinoplasty or endoscopic sinus surgery; however, dizziness may be a handicap for ambulatory use.
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Anesthesia and analgesia · Aug 2004
Randomized Controlled Trial Comparative Study Clinical TrialDoes halothane really preserve cardiac baroreflex better than sevoflurane? A noninvasive study of spontaneous baroreflex in children anesthetized with sevoflurane versus halothane.
Heart rate profiles during the induction of anesthesia differ markedly between the administration of sevoflurane and halothane. Previous investigations have shown that halothane preserves cardiac parasympathetic activity more than sevoflurane. Because vagal drive to the sinus node is the main effector of arterial baroreflex control of heart rate, halothane may preserve cardiac baroreflex better than sevoflurane. ⋯ Similarly, the cross-spectral analysis between systolic blood pressure and RRI showed a decrease of the gain calculated in the low-frequency band, but the gain in the respiratory band was higher with halothane compared with sevoflurane. In children, the induction of anesthesia with halothane and sevoflurane is associated with a marked decrease of cardiac baroreflex activity. The persistence of respiratory RRI fluctuations under halothane might reflect reflex respiratory arrhythmia rather than efficient parasympathetic baroreflex activity.