Anesthesia and analgesia
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Anesthesia and analgesia · Jan 2002
Randomized Controlled Trial Clinical TrialThe efficacy of preemptive Milrinone or Amrinone therapy in patients undergoing coronary artery bypass grafting.
Acute deterioration in ventricular function and oxygen transport is common after cardiac surgery. We hypothesized that milrinone or amrinone may reduce their occurrence and catecholamine requirements and increase cellular enzyme levels in patients undergoing coronary artery bypass. In 45 patients, we randomly administered milrinone 50 microg/kg plus 0.5 microg x kg(-1) x min(-1) infusion for 10 h, amrinone 1.5 mg/kg plus 10 microg x kg(-1) x min(-1) infusion for 10 h, or placebo at release of aortic cross-clamp. Hemodynamic variables, dopamine requirement, and laboratory values were recorded. At the postoperative nadir, stroke volume index was higher in the Milrinone and Amrinone groups (mean +/- SD, 27.8 +/- 4.0 and 26.1 +/- 3.2 vs. 20.4 +/- 5.1 mL x min (-1) x m(-2) per beat, P < 0.0001), and oxygen transport index was higher (354.7 +/- 57.8 and 353.7 +/- 91.2 vs 283.0 +/- 83.9 mL. min(-1) x m(-2), P = 0.009). The postoperative dopamine requirement was less (6.6 +/- 2.7 and 6.8 +/- 2.6 vs 10.4 +/- 2.0 mg/kg, P < 0.008), and postoperative serum lactate, alanine and aspartate aminotransferase, lactate dehydrogenase, creatinine kinase, C-reactive protein, and glucose levels were less (P < 0.01). The mean postoperative heart rate was faster in the Milrinone group than in the Amrinone and Placebo groups (96.8 +/- 10.3 vs. 86.9 +/- 9.5 and 87.8 +/- 10.8 bpm, P < 0.01). Milrinone and amrinone administered preemptively reduce postoperative deterioration in cardiac function and oxygen transport, dopamine requirement, and increases in serum lactate, glucose, and enzyme levels, although milrinone may increase heart rate. ⋯ Preemptive milrinone or amrinone administration before separation from cardiopulmonary bypass in cardiac surgical patients not only ameliorates postoperative deterioration in cardiac function and oxygen transport, but also reduces dopamine requirement and increases serum lactate, glucose, and cellular enzyme levels, although milrinone may increase heart rate.
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Anesthesia and analgesia · Jan 2002
Randomized Controlled Trial Clinical TrialThermoregulatory response to intraoperative head-down tilt.
Thermoregulation interacts with cardiovascular regulation within the central nervous system. We therefore evaluated the effects of head-down tilt on intraoperative thermal and cardiovascular regulation. Thirty-two patients undergoing lower-abdominal surgery were randomly assigned to the 1) supine, 2) 15 degrees -20 degrees head-down tilt, 3) leg-up, or 4) combination of leg-up and head-down tilt position. Core temperature and forearm minus fingertip skin-temperature gradients (an index of peripheral vasoconstriction) were monitored for 3 h after the induction of combined general and lumbar epidural anesthesia. We also determined cardiac output and central-venous and esophageal pressures. Neither right atrial transmural pressure nor cardiac index was altered in the Head-Down Tilt group, but both increased significantly in the Leg-Up groups. The vasoconstriction threshold was reduced in both leg-up positions but was not significantly decreased by head-down tilt. Final core temperatures were 35.2 degrees C +/- 0.2 degrees C (mean +/- SEM) in the Supine group, 35.0 degrees C +/- 0.2 degrees C in the Head-Down Tilt group, 34.2 degrees C +/- 0.2 degrees C in the Leg-Up group (P < 0.05 compared with supine), and 34.3 degrees C +/- 0.2 degrees C when leg-up and head-down tilt were combined (P < 0.05 compared with supine). These results confirm that elevating the legs increases right atrial transmural pressure, reduces the vasoconstriction threshold, and aggravates intraoperative hypothermia. Surprisingly, maintaining a head-down tilt did not increase right atrial pressure. ⋯ Intraoperative hypothermia is exaggerated when patients are maintained in the leg-up position because the vasoconstriction threshold is reduced. However, head-down tilt (Trendelenburg position) does not reduce the vasoconstriction threshold or aggravate hypothermia. The head-down tilt position thus does not require special perioperative thermal precautions or management unless the leg-up position is used simultaneously.
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Anesthesia and analgesia · Jan 2002
Randomized Controlled Trial Clinical TrialThe preemptive analgesic effect of rofecoxib after ambulatory arthroscopic knee surgery.
Nonsteroidal antiinflammatory drugs (NSAIDs) provide effective postoperative analgesia after arthroscopic knee surgery. Some investigators have suggested that the preemptive administration of NSAIDs may reduce postoperative analgesic requirements and hypersensitivity. We evaluated the analgesic effect of administering rofecoxib either before or after surgical incision in patients undergoing arthroscopic knee surgery under local anesthesia. Sixty patients undergoing arthroscopic meniscectomy were randomized into three groups. All patients received intraarticular bupivacaine 0.25% pre- and postsurgery together with IV sedation using midazolam and propofol. The Preincisional group received a single 50 mg dose of rofecoxib 1 h before surgery, the Postincisional group received rofecoxib 50 mg after the completion of surgery, and the Placebo group received a placebo tablet before surgery. Pain scores, the time to first opioid use, and 24-h analgesic use were recorded. Analgesic duration, defined as the time from completion of surgery until first opioid use, was significantly longer in those patients receiving pre- (803 +/- 536 min) versus postincisional (461 +/- 344 min) rofecoxib or placebo (318 +/- 108 min). The 24 h acetaminophen/oxycodone use was less in the Preincisional group (1.5 +/- 0.6 pills) versus the Postincisional group (3.3 +/- 1.3 pills) or the Placebo group (5.5 +/- 1.6 pills). Pain scores with movement were lower in the Preincisional group at all postoperative time intervals. We conclude that rofecoxib provides effective postoperative analgesia for arthroscopic meniscectomy. Further, the administration of rofecoxib 50 mg before surgery provides a longer duration of postoperative analgesia, less 24 h opioid use, and lower incidental pain scores compared with administering the drug after the completion of surgery. ⋯ The administration of rofecoxib 50 mg before arthroscopic knee surgery provides a longer duration of analgesia, less 24-h opioid use, and lower pain scores than administering the drug after the completion of surgery.
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Anesthesia and analgesia · Jan 2002
Randomized Controlled Trial Clinical TrialRemifentanil provides hemodynamic stability and faster awakening time in transsphenoidal surgery.
In this prospective study, we evaluated the effects of remifentanil in ASA I-II patients undergoing transsphenoidal surgery. After the induction of anesthesia, patients were randomly allocated to the Isoflurane (n = 22, 60% nitrous oxide, isoflurane up to 2% end-tidal) or Remifentanil group (n = 21, 60% nitrous oxide, 0.5% end-tidal isoflurane, remifentanil up to 2 microg x kg(-1) x min(-1)). If mean arterial pressure (MAP) increased >80 mm Hg during maximal dosage of isoflurane or remifentanil, labetalol was administered. At the end of anesthesia, extubation and awakening times, respiratory rate, SpO(2), MAP, heart rate, and adverse effects were recorded. Hemodynamics and bleeding (minimal, mild, moderate, severe) were not different between groups. Bleeding grade increased with MAP >80 mm Hg (P < 0.001). Labetalol was administered to 20 patients in the Isoflurane group, and 10 patients in the Remifentanil group (P < 0.01). The dose of labetalol was larger in the Isoflurane group (1.0 +/- 0.6 versus 0.5 +/- 0.7 mg/kg, P < 0.05). Time to extubation did not differ, whereas time to follow commands was shorter in Remifentanil patients (16 +/- 8 versus 10 +/- 2 min, P < 0.01). No adverse effects occurred in the early postoperative period. ⋯ In patients undergoing transsphenoidal surgery, balanced anesthesia with remifentanil (0.22 +/- 0.17 microg x kg(-1) x min(-1)) provides faster awakening time, as compared with large-dose volatile-based anesthesia, without the risk of postoperative opioid respiratory depression.
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Anesthesia and analgesia · Jan 2002
Randomized Controlled Trial Clinical TrialThe effects of three different analgesia techniques on long-term postthoracotomy pain.
In this clinical, randomized, prospective study, we compared the effects of three different analgesia techniques (thoracic epidural analgesia [TEA] with and without preoperative initiation and IV patient-controlled analgesia [IV-PCA]) on postthoracotomy pain in 69 patients. In two groups, a thoracic epidural catheter was inserted preoperatively. Group Pre-TEA had bupivacaine and morphine solution preoperatively and intraoperatively. Postoperative analgesia was maintained with epidural PCA with a similar solution. Group Post-TEA, with no intraoperative medication, had the same postoperative analgesia as Group Pre-TEA plus the bolus dose. Group IV-PCA received only IV-PCA with morphine for postoperative analgesia. Pain was evaluated every 4 h during the first 48 h at rest, cough, and movement. Pre-TEA was associated with decreased pain compared with the other groups. Six months later, the patients were asked about their pain. The incidence and the intensity of pain were most frequent in Group IV-PCA (78%) and were the least in Group Pre-TEA (45%) (Group Pre-TEA versus Group IV-PCA, P = 0.0233; Group Pre-TEA versus Group IV-PCA, P = 0.014). Patients having pain on the second postoperative day had 83% chronic pain. TEA with preoperative initiation is a preferable method in preventing acute and long-term thoracotomy pain. ⋯ Preoperatively initiated thoracic epidural analgesia has the most satisfying results in controlling postthoracotomy pain in the acute and long-term period, and it is associated with a decreased incidence (and intensity) of chronic pain compared with postoperative (epidural or IV) analgesia. Chronic pain has an incidence of 62%.