Anesthesia and analgesia
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Anesthesia and analgesia · Mar 1999
Randomized Controlled Trial Comparative Study Clinical TrialRemifentanil administration during monitored anesthesia care: are intermittent boluses an effective alternative to a continuous infusion?
This randomized, double-blind study was designed to evaluate the analgesic effectiveness and respiratory stability of remifentanil when administered as intermittent bolus injections, a variable-rate infusion, or a combination of a constant basal infusion supplemented with intermittent boluses during monitored anesthesia care (MAC). Forty-five patients undergoing extracorporeal shock wave lithotripsy (ESWL) procedures were randomly assigned to one of the three modes of remifentanil administration. All patients received midazolam 2 mg i.v., followed by a propofol infusion at 50 microg x kg(-1) x min(-1). Two minutes before administering a series of test shock waves: Group I received a remifentanil infusion of 0.1 microg x kg(-1) x min(-1), and a saline bolus (5 mL); Group II received a saline infusion and a remifentanil bolus (25 microg in 5 mL); and Group III received a remifentanil infusion of 0.05 microg x kg(-1) x min(-1), and a remifentanil bolus (12.5 microg in 5 mL). The average pain intensity was scored on an 11-point scale, with 0 = no pain to 10 = severe pain. During the ESWL procedure, pain was treated by increasing the study drug infusion rate by 25%-50% and administering 5-mL bolus injections of the study medication in Groups I (saline) and II (remifentanil 25 microg). In Group III, intermittent 5-mL boluses (remifentanil 12.5 microg) were administered as needed. Patients in Groups II and III reported lower pain scores in response to the test shocks. Significantly more remifentanil was administered in Group I (379 +/- 207 microg) than in Group II (201 +/- 136 microg). However, more interventions were required for the treatment of intraoperative pain in the intermittent bolus group (Group II). When remifentanil is administered as the analgesic component of a MAC technique, these data support the use of intermittent bolus doses (12.5-25 microg) alone or in combination with a basal infusion (0.05 microg x kg(-1) x min(-1)) as alternatives to a variable-rate continuous infusion. ⋯ In this study, three different modes of remifentanil administration were used during monitored anesthesia care for extracorporeal shock wave lithotripsy procedures. These results suggest that using intermittent bolus injections of remifentanil (25 microg) or a continuous infusion (0.05 microg x kg(-1) x min(-1)) supplemented with intermittent bolus (12.5 microg) injections may be more effective than a variable-rate infusion of remifentanil during propofol sedation.
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Anesthesia and analgesia · Mar 1999
Randomized Controlled Trial Comparative Study Clinical TrialA comparison among nalbuphine, meperidine, and placebo for treating postanesthetic shivering.
Postanesthetic shivering (PS) is distressing for patients and may induce a variety of complications. In this prospective, double-blinded, randomized study, we evaluated the value of nalbuphine, compared with meperidine and saline, for treating PS. Ninety adult patients were included in the study. Group 1 (n = 30) received i.v. nalbuphine 0.08 mg/kg, Group 2 (n = 30) received i.v. meperidine 0.4 mg/kg, and Group 3 (n = 30) received i.v. saline. Treatment that stopped shivering was considered to have been successful. The results demonstrated that, 5 min after treatment, both nalbuphine and meperidine provided a rapid and potent anti-shivering effect on PS, with high response rates of 80% and 83%, compared with those of saline (0%) (P < 0.01). Thirty minutes after injection, the response rates of nalbuphine and meperidine were 90% and 93%, respectively, compared with 17% in the saline group (P < 0.01). The differences between nalbuphine and meperidine were not significant. We conclude that nalbuphine may be an alternative to meperidine for treating PS. ⋯ We evaluated nalbuphine versus meperidine and saline for treating postanesthetic shivering. Our results demonstrate that both nalbuphine and meperidine provide a similar rapid and potent anti-shivering effect. Nalbuphine may be an alternative to meperidine for treating postanesthetic shivering.
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Anesthesia and analgesia · Mar 1999
Randomized Controlled Trial Comparative Study Clinical TrialPulmonary function changes after interscalene brachial plexus anesthesia with 0.5% and 0.75% ropivacaine: a double-blinded comparison with 2% mepivacaine.
The purpose of this investigation was to compare, in a prospective, double-blinded fashion, 0.5% and 0.75% ropivacaine with 2% mepivacaine to determine their effects on respiratory function during interscalene brachial plexus (IBP) anesthesia. With ethical committee approval and written, informed consent, 30 healthy patients presenting for elective shoulder capsuloplastic or acromioplastic procedures were randomized to receive IBP anesthesia by 20 mL of either 0.5% ropivacaine (n = 10), 0.75% ropivacaine (n = 10), or 2% mepivacaine (n = 10). Block onset time, pulmonary function variables, ipsilateral hemidiaphragmatic motion (ultrasonographic evaluation), and first requirement of postoperative analgesic were evaluated. Surgical anesthesia (loss of pinprick sensation from C4 to C7 and motor block of the shoulder joint) was achieved later with 0.5% ropivacaine than with either 0.75% ropivacaine or 2% mepivacaine (P < 0.05), whereas the first pain medication was requested later with both ropivacaine concentrations than with mepivacaine (P < 0.0005). No differences in quality of the block or patient acceptance were observed in the three groups. All 30 patients had ipsilateral hemidiaphragmatic paresis and large mean decreases in forced vital capacity (ropivacaine 0.5%: 40% +/- 17%, ropivacaine 0.75%: 41% +/- 22%, mepivacaine 2%: 39% +/- 21%) and forced expiratory volume at 1 s (ropivacaine 0.5%: 30% +/- 19%, ropivacaine 0.75%: 38% +/- 26%, mepivacaine 2%: 40% +/- 10%). We conclude that, when performing IBP anesthesia, 0.5% ropivacaine does not decrease the incidence of ipsilateral paresis of the hemidiaphragm compared with 0.75% ropivacaine and 2% mepivacaine. ⋯ During the first 30 min after placing interscalene brachial plexus anesthesia, 0.5% ropivacaine does not provide clinically relevant advantages in terms of pulmonary function changes compared with either 0.75% ropivacaine or 2% mepivacaine. However, 0.75% ropivacaine allows a short onset, similar to that of mepivacaine, with long postoperative analgesia.
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Anesthesia and analgesia · Mar 1999
Randomized Controlled Trial Comparative Study Clinical TrialArterial oxygenation during one-lung ventilation: combined versus general anesthesia.
The optimal anesthetic management of patients undergoing thoracotomy for pulmonary resection has not been definitely determined. We evaluated whether general i.v. anesthesia (propofol-fentanyl) provides superior PaO2 during one-lung ventilation (OLV) compared with thoracic epidural anesthesia (TEA) with supplemental local and general anesthetics. We studied 60 patients who had prolonged periods of OLV for elective thoracic surgery for lung cancer and who were prospectively randomized into two groups. In 30 patients (GA group), fentanyl/propofol/rocuronium anesthesia was used. Another 30 patients (TEA group) were anesthetized with propofol/rocuronium/epidural thoracic bupivacaine 0.5%. A double-lumen endotracheal tube was inserted, and mechanical ventilation with 100% oxygen was used during the entire study. Arterial and venous blood gases were recorded before surgery in a lateral position with two-lung ventilation, 15 and 30 min after OLV (OLV + 15 and OLV + 30, respectively) in all patients. We measured PaO2, venous central oxygen tension, arterial and central venous oxygen saturation, venous admixture percentage (Qs/Qt%), and arterial and central venous oxygen content. The mean values for PaO2 during OLV in the GA group after 15 min (175 mm Hg) and 30 min (182 mm Hg) were significantly (P < 0.05) higher compared with the TEA group (120 and 118 mm Hg, respectively). Furthermore, Qs/Qt% was significantly (P < 0.05) increased in the TEA group during OLV. There were no other significant differences. We conclude that using the TEA regimen is associated with a lower PaO2 and a larger intrapulmonary shunt during OLV than with total i.v. anesthesia alone. ⋯ Sixty patients undergoing elective lung surgery during a prolonged period of intraoperative one-lung ventilation were studied and randomized to receive general i.v. anesthesia or general i.v. anesthesia combined with thoracic epidural anesthesia. The arterial oxygenation in the first group was better than that in the second group during one-lung ventilation.
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Anesthesia and analgesia · Mar 1999
Randomized Controlled Trial Clinical TrialAnesthesia for in vitro fertilization: the addition of fentanyl to 1.5% lidocaine.
Ultrasonically guided transvaginal oocyte retrieval is relatively short procedure that is performed on an out-patient basis. The optimal anesthetic technique should allow good surgical anesthesia with minimal side effects, a short recovery time, and, if possible, a high rate of successful pregnancy. Spinal anesthesia is often used in this institution, as well as many others, for this procedure. The addition of fentanyl may be effective for both intraoperative and postoperative pain relief. We assessed the effect of adding fentanyl to 1.5% lidocaine in women undergoing ultrasonically guided oocyte retrieval. Seventy-eight women were randomized to receive 45 mg of hyperbaric 1.5% lidocaine with or without 10 microg of fentanyl. Visual analog scale (VAS) pain scores were lower in the operating room (OR) (P < 0.05) and postanesthesia care unit (PACU) (P < 0.0005) for the group that received fentanyl. In addition, the amount of narcotic required in the PACU was less in the fentanyl group (P < 0.005). There was no difference in VAS scores the evening of or 24 h after the procedure. The amount of analgesics and narcotics required after discharge was the same for both groups. Timed variables, such as time to urination, ambulation, and discharge, were the same for both groups of women. The addition of fentanyl to lidocaine for transvaginal oocyte retrieval results in a more comfortable patient in the OR and PACU. ⋯ This study demonstrates that when fentanyl is added to a local anesthetic, lidocaine, with spinal anesthesia for egg retrieval procedures, patients are more comfortable during the procedure compared with those who receive lidocaine alone. In addition, the narcotic requirements of patients are less in the postanesthesia care unit.