Anesthesia and analgesia
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Anesthesia and analgesia · Mar 1998
The effect of electroconvulsive treatment on thermal hyperalgesia and mechanical allodynia in a rat model of peripheral neuropathy.
We tested the ability of electroconvulsive treatment (ECT) to block thermal hyperalgesia and mechanical allodynia in rats with peripheral neuropathy. Repeated ECT (six times daily) significantly reduced thermal hyperalgesia 48 h after the end of the final treatment but had no significant effects on mechanical allodynia. Single ECT had no significant effect on thermal hyperalgesia or mechanical allodynia. Neither single nor repeated ECT had any significant effect on the withdrawal response of sham-operated paws and untreated rats to thermal and mechanical stimuli. The anti-thermal hyperalgesic effect of repeated ECT was reversed by the previous administration of nifedipine (L-type Ca2+ channel blocker). We conclude that, due to effects on the voltage dependent calcium channel, ECT modified one of the pain behaviors induced by nerve injury. ECT may be of use in the treatment of human neuropathic pain. ⋯ We showed that repeated electroconvulsive treatment reduced pain responses to heat stimulation after sciatic nerve injury in rats. This study implies a possible therapeutic effect of electroconvulsive treatment on neuropathic pain.
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Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Meta Analysis Comparative Study Clinical TrialThe comparative effects of postoperative analgesic therapies on pulmonary outcome: cumulative meta-analyses of randomized, controlled trials.
We performed meta-analyses of randomized, control trials to assess the effects of seven analgesic therapies on postoperative pulmonary function after a variety of procedures: epidural opioid, epidural local anesthetic, epidural opioid with local anesthetic, thoracic versus lumbar epidural opioid, intercostal nerve block, wound infiltration with local anesthetic, and intrapleural local anesthetic. Measures of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), vital capacity (VC), peak expiratory flow rate (PEFR), PaO2, and incidence of atelectasis, pulmonary infection, and pulmonary complications overall were analyzed. Compared with systemic opioids, epidural opioids decreased the incidence of atelectasis (risk ratio [RR] 0.53, 95% confidence interval [CI] 0.33-0.85) and had a weak tendency to reduce the incidence of pulmonary infections (RR 0.53, 95% CI 0.18-1.53) and pulmonary complications overall (RR 0.51, 95% CI 0.20-1.33). Epidural local anesthetics increased PaO2 (difference 4.56 mm Hg, 95% CI 0.058-9.075) and decreased the incidence of pulmonary infections (RR 0.36, 95% CI 0.21-0.65) and pulmonary complications overall (RR 0.58, 95% CI 0.42-0.80) compared with systemic opioids. Intercostal nerve blockade tends to improve pulmonary outcome measures (incidence of atelectasis: RR 0.65, 95% CI 0.27-1.57, incidence of pulmonary complications overall: RR 0.47, 95% CI 0.18-1.22), but these differences did not achieve statistical significance. There were no clinically or statistically significant differences in the surrogate measures of pulmonary function (FEV1, FVC, and PEFR). These analyses support the utility of epidural analgesia for reducing postoperative pulmonary morbidity but do not support the use of surrogate measures of pulmonary outcome as predictors or determinants of pulmonary morbidity in postoperative patients. ⋯ When individual trials are unable to produce significant results, it is often because of insufficient patient numbers. It may be impossible for a single institution to study enough patients. Meta-analysis is a useful tool for combining the data from multiple trials to increase the patient numbers. These meta-analyses confirm that postoperative epidural pain control can significantly decrease the incidence of pulmonary morbidity.
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Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Comparative Study Clinical TrialVomiting after adenotonsillectomy in children: a comparison of ondansetron, dimenhydrinate, and placebo.
We compared the effectiveness of ondansetron, dimenhydrinate, and placebo for the prevention of postoperative vomiting in children after adenotonsillectomy. In a randomized, placebo-controlled, double-blind study, 74 children, 2-10 yr of age scheduled for adenotonsillectomy as outpatients were given a single i.v. dose of ondansetron (0.1 mg/kg, n = 26), dimenhydrinate (0.5 mg/kg, n = 25), or placebo (saline, n = 23) at induction of anesthesia. The incidence of retching and vomiting (POV) and side effects observed 24 h after surgery were recorded. Demographic data were similar among the three groups. The 24-h incidence of POV was 42%, 79%, and 82% in the ondansetron, dimenhydrinate, and placebo groups, respectively (ondansetron compared with dimenhydrinate [P < 0.02] or placebo [P < 0.01]). The study was stopped after two children vomited large volumes of bloody fluid 9 and 22 h after surgery without previous signs of occult bleeding. Both children had received ondansetron. We conclude that ondansetron is superior to dimenhydrinate or placebo for the prevention of POV after adenotonsillectomy in children. Antiemetics may mask the signs of bleeding after adenotonsillectomy. ⋯ I.v. ondansetron (0.1 mg/kg) is more effective than both dimenhydrinate and placebo in preventing vomiting after adenotonsillectomy in healthy children. However, antiemetics may also mask the presence of blood in the stomach by preventing vomiting, and this should be appreciated when adenotonsillectomy is performed on an outpatient basis.
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Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Clinical TrialFactors that predict the use of positive inotropic drug support after cardiac valve surgery.
Left ventricular dysfunction is common after cardiac surgery and is often treated with positive inotropic drugs (PIDs). We hypothesized that the use of PIDs after cardiac valve surgery would have significant associations with the valvular pathophysiology and surgical procedure, and unlike the case for patients undergoing coronary artery surgery, would be unrelated to duration of cardiopulmonary bypass (CPB) or of aortic clamping. One hundred forty-nine consenting patients undergoing cardiac valve surgery were studied. Patients with hepatic or renal failure, or New York Heart Association class IV cardiac symptoms, were excluded. Patients were considered to have received PIDs if they received an infusion of amrinone, dobutamine, epinephrine, or dopamine (> or = 5 microg x kg[-1] x min[-1]). PIDs were received by 78 patients (52%). In a univariate model, older age, history of congestive heart failure, decreasing left ventricular ejection fraction, longer durations of CPB, and concurrent coronary artery surgery significantly increased the likelihood of PID support. There was also significant variation by anesthesiologist in the administration of PIDs. The specific diseased valve and valvular stenosis or insufficiency did not influence the likelihood of receiving PID support. In a multivariable model, age, history of congestive heart failure, decreasing left ventricular ejection fraction, and anesthesiologist were significantly associated with the likelihood of PID support, but duration of CPB and concurrent coronary artery surgery were not. In conclusion, patient age and ventricular function, as well as physician preferences, predicted the need for inotropic drug support; however, neither the specific valvular lesion, nor duration of CPB were strongly predictive in a multivariable model. ⋯ We evaluated factors related to use of positive inotropic drugs after cardiac valve surgery. The likelihood of a patient receiving these drugs increases with advancing age and with more severe preoperative left ventricular dysfunction, but was not influenced by the specific diseased valve or the duration of cardiopulmonary bypass.
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Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Clinical TrialAlkalinization of lidocaine does not hasten the onset of axillary brachial plexus block.
We assessed the onset of sensory and motor blockade as well as the distribution of sensory blockade after axillary brachial plexus block with 1.5% lidocaine hydrochloride 1:200,000 epinephrine with and without sodium bicarbonate in 38 patients. The onset of analgesia and anesthesia was recorded over the distributions of the median, ulnar, radial, and medial cutaneous nerves of the forearm, medial cutaneous and lateral cutaneous nerves of the arm, and musculocutaneous nerve. The onset of motor blockade of elbow and wrist movements was also recorded. Data were analyzed by using survival techniques and compared by using log rank tests. Only the onset of analgesia in the medial cutaneous nerves of the arm and forearm, and the onset of anesthesia in the medial cutaneous nerve of the arm were significantly faster (P < 0.05) with alkalinization of lidocaine. Our study showed that alkalinization of lidocaine does not significantly hasten block onset in most terminal nerve distributions. ⋯ We examined whether alkalinizing a local anesthetic would quicken the onset of a regional upper limb nerve blockade. We found that alkalinization of lidocaine did not offer a significant clinical advantage in axillary brachial plexus blockade.