Anesthesia and analgesia
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Anesthesia and analgesia · Jun 1999
Clinical TrialTissue heat content and distribution during and after cardiopulmonary bypass at 17 degrees C.
We measured afterdrop and peripheral tissue temperature distribution in eight patients cooled to approximately 17 degrees C during cardiopulmonary bypass and subsequently rewarmed to 36.5 degrees C. A nasopharyngeal probe evaluated trunk and head temperature and heat content. Peripheral tissue temperature (arm and leg temperature) and heat content were estimated using fourth-order regressions and integration over volume from 30 tissue and skin temperatures. Peripheral tissue temperature decreased to 19.7+/-0.9 degrees C during bypass and subsequently increased to 34.3+/-0.7 degrees C during 104+/-18 min of rewarming. The core-to-peripheral tissue temperature gradient was -5.9+/-0.9 degrees C at the end of cooling and 4.7+/-1.5 degrees C at the end of rewarming. The core-temperature afterdrop was 2.2+/-0.4 degrees C and lasted 89+/-15 min. It was associated with 1.1+/-0.7 degrees C peripheral warming. At the end of cooling, temperatures at the center of the upper and lower thigh were (respectively) 8.0+/-5.2 degrees C and 7.3+/-4.2 degrees C cooler than skin temperature. On completion of rewarming, tissue at the center of the upper and lower thigh were (respectively) 7.0+/-2.2 degrees C and 6.4+/-2.3 degrees C warmer than the skin. When estimated systemic heat loss was included in the calculation, redistribution accounted for 73% of the afterdrop, which is similar to the contribution observed previously in nonsurgical volunteers. ⋯ Temperature afterdrop after bypass at 17 degrees C was 2.2+/-0.4 degrees C, with approximately 73% of the decrease in core temperature resulting from core-to-peripheral redistribution of body heat. Cooling and rewarming were associated with large radial tissue temperature gradients in the thigh.
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Anesthesia and analgesia · Jun 1999
Clinical Trial Controlled Clinical TrialPostoperative analgesia with controlled-release oxycodone for outpatient anterior cruciate ligament surgery.
Reconstruction of the anterior cruciate ligament (ACL) of the knee is associated with a considerable degree of postoperative pain. Although immediate-release oral opioids are usually effective in relieving moderate to severe pain, they must be given every 4-6 h. A controlled-release (CR) formulation of oxycodone maintains therapeutic opioid concentrations for a more prolonged period, thus providing sustained pain relief. We designed this study to determine whether CR oxycodone is more effective and clinically acceptable than immediate-release oxycodone for managing pain after ambulatory ACL repair surgery. All patients received a standard general anesthetic and postoperative analgesic regimen with one of three oxycodone dosing regimens: oxycodone 10 mg every 4 h as needed, oxycodone 10 mg every 4 h, and CR oxycodone 20 mg every 12 h. Rescue analgesic consisted of oxycodone 5 mg every 6 h as needed. At 24, 36, 48, 60, and 72 h, there was a difference in pain scores among the groups (P < 0.0001); there was less pain in the CR oxycodone group. At most times, the fixed-dose group had lower pain scores than the as-needed group. The sedation scores were significantly different at 12 h (P < 0.02) and at 24, 36, 48, 60, and 72 h (P < 0.0001); the patients were more alert in the CR oxycodone group. The 72-h consumption of oxycodone was less in the CR oxycodone group (P < 0.0001). The patients had less sleep disturbance (P < 0.0001), were more satisfied (P < 0.0001), and experienced less vomiting (P < 0.02) in the CR oxycodone group compared with the other two groups. In conclusion, using CR oxycodone in the immediate 72 h after ambulatory ACL surgery provides more effective analgesia with less sedation, sleep disturbance, and postoperative vomiting compared with oxycodone prescribed on either a fixed dose or as-needed schedule. ⋯ A controlled-release formulation of oxycodone in patients undergoing anterior cruciate ligament repair on an ambulatory basis provides significant analgesic benefit and a lowering of side effects compared with either fixed-dose or as-needed oxycodone regimens.
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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.
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Anesthesia and analgesia · Jun 1999
Letter Randomized Controlled Trial Clinical TrialAssessment of renal effects of sevoflurane in elderly patients using urinary markers.