Anesthesia and analgesia
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Anesthesia and analgesia · Jun 1999
Randomized Controlled Trial Clinical TrialAdding clonidine to lidocaine for intravenous regional anesthesia prevents tourniquet pain.
Tourniquet pain often complicates the use of the pneumatic tourniquet during surgical procedures performed under IV regional anesthesia. Clonidine-containing local anesthetic solutions have better analgesic properties than plain solutions when used for spinal, epidural, or peripheral blocks. We tested the hypothesis that the addition of clonidine may improve the quality of IV regional anesthesia, especially tourniquet tolerance. Forty patients were allocated randomly in a double-blinded, randomized study to receive 40 mL of 0.5% lidocaine and either 1 mL of isotonic saline or clonidine (150 microg). A double-cuffed tourniquet was kept inflated until patients complained of pain, leading to release of the distal cuff. Pain at the tourniquet site, at the surgical site, and in the distal part of the arm was rated on a visual analog scale (VAS) and a verbal rating scale (VRS) every 15 min during tourniquet placement and every 15 min for 1 h after tourniquet deflation. Motor blockade, sedation, arterial pressure, and heart rate were also recorded. VAS and VRS scores were significantly lower in the clonidine group 30 and 45 min after tourniquet inflation. The tolerance for the distal tourniquet was also significantly longer in the clonidine group (median [range]: 22 [10-40] vs 10 [5-20] min; P < 0.05); motor blockade was comparable between the two groups. Pain was not different in the two groups after tourniquet release. The clonidine group experienced a higher degree of sedation. We conclude that clonidine improves tourniquet tolerance when added to a local anesthetic solution. ⋯ A 150-microg dose of clonidine added to lidocaine improved tourniquet tolerance during IV regional anesthesia.
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Anesthesia and analgesia · Jun 1999
Meta AnalysisComparative efficacy and safety of ondansetron, droperidol, and metoclopramide for preventing postoperative nausea and vomiting: a meta-analysis.
Postoperative nausea and vomiting are important causes of morbidity after anesthesia and surgery. We performed a meta-analysis of published, randomized, controlled trials to determine the relative efficacy and safety of ondansetron, droperidol, and metoclopramide for the prevention of postoperative nausea and vomiting. We performed a literature search of English references using both the MEDLINE database and a manual search. Double-blinded, randomized, controlled trials comparing the efficiency of the prophylactic administration of ondansetron, droperidol, and/or metoclopramide therapy during general anesthesia were included. A total of 58 studies were identified, of which 4 were excluded for methodological concerns. For each comparison of drugs, a pooled odds ratio (OR) with a 95% CI was calculated using a random effects model. Ondansetron (pooled OR 0.43, 95% CI 0.31, 0.61; P < 0.001) and droperidol (pooled OR 0.68, 95% CI 0.54, 0.85; P < 0.001) were more effective than metoclopramide in preventing vomiting. Ondansetron was more effective than droperidol in preventing vomiting in children (pooled OR 0.49; P = 0.004), but they were equally effective in adults (pooled OR 0.87; P = 0.45). The overall risk of adverse effects was not different among drug combinations. We conclude that ondansetron and droperidol are more effective than metoclopramide in reducing postoperative vomiting. ⋯ We performed a systematic review of published, randomized, controlled trials to determine the relative efficacy and safety of ondansetron, droperidol, and metoclopramide for preventing postoperative nausea and vomiting. Ondansetron and droperidol were more effective than metoclopramide in reducing postoperative vomiting. The overall risk of adverse effects did not differ.
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Anesthesia and analgesia · Jun 1999
Randomized Controlled Trial Comparative Study Clinical TrialHemodynamic and catecholamine stress responses to insertion of the Combitube, laryngeal mask airway or tracheal intubation.
In a prospective, randomized, and controlled trial, we compared the stress responses after insertion of the Combitube (CT; Kendall-Sheridan Catheter Corp., Argyle, NY), the laryngeal mask airway (LMA), or endotracheal intubation (ET). Seventy-five patients scheduled for routine urological or gynecological surgery were randomly allocated to one of three groups and were ventilated via either an ET, a LMA, or a CT. All three devices could be inserted easily and rapidly, providing adequate ventilation and oxygenation. Insertion of the CT was associated with a significant increase in mean maximal systolic arterial pressure (160+/-32 mm Hg) and diastolic arterial pressure (91+/-17 mm Hg) compared with ET (140+/-24, 78+/-11 mm Hg; P < 0.05, P < 0.01, respectively) or insertion of the LMA (115+/-33,63+/-22 mm Hg, both P < 0.001). The mean maximal epinephrine and norepinephrine plasma concentrations after insertion of the CT (37.3+/-31.1 and 279+/-139 pg/mL, respectively) were significantly higher than those after ET (35.8+/-89.8 and 195+/-58 pg/mL, respectively) or insertion of a LMA (17.3+/-13.3 and 158+/-67 pg/mL, respectively). This might be attributed to the pressure of the pharyngeal cuff of the CT on the anterior pharyngeal wall. We conclude that insertion of the CT causes a pronounced stress response and that precautions should be taken when used in patients at risk of hypertensive bleeding. ⋯ In this study, we showed that the hemodynamic and catecholamine stress responses after insertion of the Combitube (Kendall-Sheridan Catheter Corp., Argyle, NY) were significantly higher compared with laryngeal mask airway or endotracheal intubation. We conclude that the increased stress response to insertion of a Combitube may represent a serious hazard to patients with cardiovascular disease.
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Anesthesia and analgesia · Jun 1999
Clinical TrialD-Dimer formation during cardiac and noncardiac thoracic surgery.
The ability to make therapeutic decisions regarding excessive fibrinolysis in the perioperative period is limited by the lack of availability of a near site monitor of fibrinolysis. We investigated the use of a latex agglutination D-dimer assay to detect perioperative fibrinolysis in patients undergoing thoracic surgery with and without extracorporeal circulation. We studied 27 patients who underwent thoracic surgery requiring cardiopulmonary bypass (CPB; coronary artery bypass grafting, n = 12; valvular surgery, n = 15) and a cohort of 20 patients who underwent noncardiac thoracic surgical procedures not requiring CPB. The purpose of this investigation was to determine the relationship among alterations in the latex agglutination D-dimer assay, use of extracorporeal circulation, type of cardiac surgical procedure, and mediastinal and/or chest tube drainage (cardiac surgery only) in patients undergoing thoracic surgery. Perioperative D-dimer levels, measured by latex agglutination, had significant (P < or = 0.05) intragroup changes among patients undergoing cardiac surgery (requiring CPB) and the cohort of patients who underwent noncardiac thoracic surgery without CPB. Although intraoperative D-dimer levels were not increased in patients undergoing noncardiac thoracic surgery, postoperative levels were significantly (P < 0.05) increased (compared with preinduction). In cardiac surgery patients requiring CPB, intraoperative D-dimer formation was significantly (P < or = 0.05) increased but did not demonstrate any intragroup (coronary artery bypass grafting versus valvular surgery) differences. Finally, D-dimer levels were not associated with postoperative mediastinal and/or chest tube accumulative drainage measured at intervals up to 48 h postoperatively in patients undergoing cardiac surgery requiring CPB. Our study indicates that the latex agglutination D-dimer assay can detect excessive fibrinolysis perioperatively, and that extracorporeal circulation can significantly influence the pattern of D-dimer formation in patients undergoing thoracic surgery. ⋯ We assessed the ability of a readily available D-dimer assay to detect excessive fibrinolysis in patients undergoing thoracic surgery with and without extracorporeal circulation. The findings demonstrate that the assay used in this investigation reflected variable amounts of fibrinolysis in patients undergoing both types of thoracic surgery.