Anesthesia and analgesia
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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 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 Clinical TrialAdenosine reduces secondary hyperalgesia in two human models of cutaneous inflammatory pain.
Secondary hyperalgesia is characterized by increased sensitivity to noxious mechanical stimuli in the area surrounding injured skin. The pathophysiological mechanisms involve increased excitability of second-order neurons located in the spinal cord, i.e., central sensitization. The mechanisms behind this phenomenon may be of importance in clinical pain, including neuropathic pain. To study the effects of systemic infusion of the endogenous compound adenosine (ADO) on sensory function, a superficial cutaneous burn injury was induced by the 4-min topical application of mustard oil or by heat (47 degrees C for 7 min) during i.v. ADO infusion (60 microg x kg(-1) x min(-1)). Healthy human subjects (n = 10 for each model) were tested, using a blinded, placebo-controlled procedure. The area of secondary hyperalgesia, as well as tactile and thermal sensory function, was tested using psychophysical methods during and after treatments. ADO significantly reduced the area of secondary hyperalgesia in both models. The maximal reduction compared with placebo was 58% +/- 20% (heat burn) and 39% +/- 13% (mustard oil burn). No other differences in sensory function were observed. The results are interpreted as an ADO-induced modulatory effect on the mechanisms of central sensitization. ⋯ We tested the effects of adenosine on the development of increased sensitivity in the skin surrounding a superficial skin injury in humans. A superficial skin bum was induced with a chemical irritant or heat. The results show that adenosine reduces the skin area with increased sensitivity surrounding the injury.