Anesthesia and analgesia
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Anesthesia and analgesia · Dec 2005
Randomized Controlled TrialEpidural fentanyl speeds the onset of sensory and motor blocks during epidural ropivacaine anesthesia.
In this study we examined the onset times of sensory and motor block during epidural ropivacaine anesthesia with and without the addition of fentanyl to the epidural solution. Forty-five young male patients undergoing knee arthroscopic surgery were randomly allocated into 3 groups of 15 patients each: epidural fentanyl (EF; epidural administration of 15 mL of 1% ropivacaine plus 100 mug fentanyl followed by IV injection of 2 mL of normal saline); IV fentanyl (IF; epidural administration of 15 mL of 1% ropivacaine plus 2 mL of normal saline followed by IV injection of 100 mug fentanyl); and control (C; epidural administration of 15 mL of 1% ropivacaine plus 2 mL of normal saline followed by IV injection of 2 mL of normal saline). The sensory and motor blocks were assessed by pinprick and modified Bromage scale, respectively. ⋯ Pruritus was observed in three patients of the EF group and one patient of the IF group. No nausea, vomiting, respiratory depression, urinary retention, or hypotension was observed in any patient. We conclude that epidural administration of the mixture of 100 mug fentanyl and 1% ropivacaine solution accelerated the onset of sensory and motor blocks during epidural ropivacaine anesthesia without significant fentanyl-related side effects.
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Anesthesia and analgesia · Dec 2005
Compartmental pharmacokinetics of dantrolene in adults: do malignant hyperthermia association dosing guidelines work?
Dantrolene is the only drug proven effective for prevention and treatment of malignant hyperthermia (MH). Current dosing recommendations are based on noncompartmental analyses and are largely empiric. They are also divergent, as evidenced by differing recommendations from the Malignant Hyperthermia Association of the United States (MHAUS) and European Sources. ⋯ Simulating MHAUS guidelines (intermittent bolus administration) yielded peak and trough plasma concentrations ranging from 6.7-22.6 mg/L. Based on our findings, we propose an infusion regimen adjusted to the initial bolus dose(s) required to control symptoms. This strategy maintains the individualized therapeutic concentrations and improves stability of plasma concentrations.
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Anesthesia and analgesia · Dec 2005
Inhibition of mitochondrial permeability transition enhances isoflurane-induced cardioprotection during early reperfusion: the role of mitochondrial KATP channels.
Inhibition of the mitochondrial permeability transition pore (mPTP) mediates the protective effects of brief, repetitive ischemic episodes during early reperfusion after prolonged coronary artery occlusion. Brief exposure to isoflurane immediately before and during early reperfusion also produces cardioprotection, but whether mPTP is involved in this beneficial effect is unknown. We tested the hypothesis that mPTP mediates isoflurane-induced postconditioning and also examined the role of mitochondrial KATP (mKATP) channels in this process. ⋯ Neither atractyloside nor 5-HD alone affected infarct size, but these drugs abolished protection by 1.0 MAC isoflurane, 10 mg/kg CsA, and 0.5 MAC isoflurane plus 5 mg/kg CsA. The results indicate that mPTP inhibition enhances, whereas opening abolishes, isoflurane-induced postconditioning. This isoflurane-induced inhibition of mitochondrial permeability transition is dependent on activation of mitochondrial KATP channels in vivo.
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Anesthesia and analgesia · Dec 2005
The safety of patient-controlled analgesia by proxy in pediatric oncology patients.
Between February 1999 and December 2003, we studied the use of patient-controlled analgesia (PCA) to control pain in 1011 children and young adults with cancer, by evaluating 4972 24-h periods of PCA usage, 576 of which involved PCA by proxy. Selection of patients for PCA by proxy was based on younger age group, neuromuscular limitation, expectation of repeated painful procedures, and terminal disease. ⋯ In the PCA by proxy group two respiratory complications, two neurological complications and one mixed respiratory and neurological complication were observed [corrected] Reversal of opioid-related respiratory or neurological effects with naloxone was required in three instances, two in the standard PCA group and one in the PCA by proxy group. Recommendations to ensure continuing safety include careful patient selection, education of proxy users, appropriate documentation, and institutional guidelines.
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Anesthesia and analgesia · Dec 2005
Meta Analysis Comparative StudyA comparison of regional versus general anesthesia for ambulatory anesthesia: a meta-analysis of randomized controlled trials.
Both regional anesthesia and general anesthesia have been proposed to provide optimal ambulatory anesthesia. We searched MEDLINE and other databases for randomized controlled trials comparing regional anesthesia and general anesthesia in ambulatory surgery patients for meta-analysis. Only major conduction blocks were considered to be regional anesthesia. ⋯ This meta-analysis indicates potential advantages for regional anesthesia, such as decreased postanesthesia care unit use, nausea, and postoperative pain. Although these factors have been proposed to reduce ambulatory surgery unit stay, neither central neuraxial block nor peripheral nerve block were associated with reduced ambulatory surgery unit time. Other factors, such as unsuitable discharge criteria and limitations of meta-analysis, may explain this discrepancy.