Anesthesia and analgesia
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Anesthesia and analgesia · Dec 1999
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialA comparison of levobupivacaine 0.125%, fentanyl 4 microg/mL, or their combination for patient-controlled epidural analgesia after major orthopedic surgery.
Levobupivacaine, the isolated S(-) isomer of bupivacaine, is less cardiotoxic than racemic bupivacaine in animal studies. We studied the effectiveness of patient-controlled epidural analgesia (PCEA) with either levobupivacaine 0.125% or fentanyl 4 microg/mL alone, or a combination of levobupivacaine and fentanyl in 65 patients after total joint arthroplasty in a prospective, random, double-blinded fashion. Intraoperatively, all patients received 20 mL of 0.75% levobupivacaine. Study medication was infused at an initial rate of 4 mL/h, with additional medication available on patient demand (2 mL/10 min). The combination of levobupivacaine and fentanyl produced better analgesia (longer time to first PCEA request; P = 0.007 combination versus fentanyl and P = 0.006 combination versus levobupivacaine) than either drug alone. Patients in the levobupivacaine groups had appreciable sensory blockade to pinprick with minimal motor impairment. Resting and dynamic visual analog scale pain scores were lower in the combination group than in the plain fentanyl group at 6 (P = 0.022 and 0.036) and 12 h (P = 0.002 and 0.001). The 24-h overall patient- and investigator-rated visual analog scale pain scores were also lower in the combination group (resting P = 0.007, dynamic P = 0.005). There was no significant difference among the groups in the incidence of postoperative nausea (26.2%), pruritus (9.2%), hypotension (23.1%), or sedation (0%). We conclude that the analgesic effects of levobupivacaine 0.125% and fentanyl (4 microg/mL) are additive and beneficial for the management of orthopedic surgical pain by the PCEA method. Patients in this study began demand-dosing later, reported lower pain scores, and had no greater risk of adverse events than those who were given either levobupivacaine or fentanyl alone. ⋯ We demonstrated a significant additive effect of the combination of levobupivacaine (0.125%) and fentanyl (4 microg/mL), compared with either drug alone, when using patient-controlled epidural analgesia in patients after total joint arthroplasty.
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Anesthesia and analgesia · Dec 1999
Randomized Controlled Trial Multicenter Study Comparative Study Clinical TrialA comparison of the analgesic efficacy of 0.25% levobupivacaine combined with 0.005% morphine, 0.25% levobupivacaine alone, or 0.005% morphine alone for the management of postoperative pain in patients undergoing major abdominal surgery.
We compared the relative efficacy of the combination of the single-isomer local anesthetic levobupivacaine and the opioid analgesic morphine versus both drugs alone for postoperative epidural analgesia after major abdominal surgical procedures. Thoracic epidural anesthesia was produced and maintained with levobupivacaine 0.75% in combination with general inhaled anesthesia without opioids. Patients were randomized to one of three postoperative treatment groups: 1) a combination of levobupivacaine 0.25% and morphine 0.005%; 2) levobupivacaine 0.25%; or 3) morphine 0.005%. Postoperatively, all epidural infusions were commenced at a rate of 4 mL/h. Patients could receive a 4 mL-bolus dose and an increase in the epidural infusion rate by 2 mL/h on request for supplemental analgesia. Patients were also allowed ketorolac as a supplemental analgesic at any time after the first analgesic request. Patients in the combination group had longer times to request for supplemental analgesia as compared with the levobupivacaine only group (P < 0.05) and a trend toward longer time to request as compared with the morphine only group (P = 0.066). Patients in the combination group had lower visual analog scale pain scores at rest and activity at 4 and 8 h and fewer requests for supplemental ketorolac (P < 0.05). In conclusion, this study demonstrates a significant improvement in postoperative analgesic efficacy with the combination of levobupivacaine and morphine for continuous epidural analgesia after major abdominal surgical procedures. ⋯ A significant improvement in postoperative analgesic efficacy is demonstrated with the thoracic epidural administration of the combination of the single-isomer local anesthetic levobupivacaine 0.25% and morphine 0.005% in patients after major abdominal surgical procedures as compared with either drug used alone.
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Anesthesia and analgesia · Dec 1999
Randomized Controlled Trial Comparative Study Clinical TrialPharmacokinetics and pharmacodynamics of ropivacaine 2 mg/mL, 5 mg/mL, or 7.5 mg/mL after ilioinguinal blockade for inguinal hernia repair in adults.
The aim of our study was to evaluate the pharmacokinetics and pharmacodynamics of ropivacaine in ilioinguinal-iliohypogastric blocks (IIB). After ethics committee approval and informed consent, 80 male adults scheduled for inguinal hernia repair were enrolled and randomized into four groups. After induction of general anesthesia, an IIB was performed double blinded in Groups 1, 2, and 3 with 0.25 mL/kg ropivacaine 2 mg/mL, 5 mg/mL, or 7.5 mg/mL and with saline in the Control group. Plasma concentration of ropivacaine was determined in venous blood using reversed-phase high-performance liquid chromatography. IIB with ropivacaine resulted in peak plasma concentrations of 0.3+/-0.15 microg/mL (Group 1) (mean +/- SD), 0.75+/-0.45 microg/mL (Group 2), or 1.57+/-0.82 microg/mL (Group 3). These concentrations occurred after 30 (15-60) min, median (range), 30 (10-60) min, and 45 (15-60) min, in the respective groups. Three of 19 patients in Group 1, 6 of 18 in Group 2, and 5 of 20 in Group 3 did not need any additional analgesics within 24 h postoperatively, but all 20 control patients did. Time to the first demand for analgesia was significantly shorter in the Control group (median 0.3 h [range 0-2.8]) compared with 1.5 h (0.5-24 h), 2 h (0.5-24 h), and 2 h (1.0-24 h) in Groups 1, 2, and 3, respectively. Three patients in Group 3 had a postoperative motor block of the femoral nerve. In conclusion, a ropivacaine dose of 0.25 mL/kg of 5 mg/mL seems adequate for IIB accompanying general anesthesia for postoperative pain relief. However, the pharmacokinetic results obtained suggest that even larger doses (0.25 mL/kg of 7.5 mg/mL ropivacaine) for IIB do not result in plasma concentrations in a toxic range. ⋯ Ropivacaine, a new local anesthetic, proved to be effective for pain relief after hernia repair in ilioinguinal blocks accompanying general anesthesia. Plasma concentrations peaked after 30-45 min, and were within safe limits after application of 0.25 mL/kg of 2, 5, or 7.5 mg/mL ropivacaine.
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Anesthesia and analgesia · Dec 1999
Randomized Controlled Trial Comparative Study Clinical TrialThe safety and efficacy of prophylactic ondansetron in patients undergoing modified radical mastectomy.
We aimed to evaluate the antiemetic efficacy, safety, and clinical utility of prophylactic ondansetron administered at the end of the surgery for the prevention of postoperative nausea and vomiting (PONV) in a homogenous population of 54 women undergoing modified radical mastectomy (MRM). A standard general anesthetic and perioperative analgesic technique were used. After surgery, patients received either saline placebo or ondansetron 4 mg IV. Episodes of PONV, as well as rescue antiemetic requirements, were recorded for the first 24 h after surgery. The 24-h incidence of PONV (33.3% vs 81.5%; P = 0.0010) was significantly lower in the ondansetron group. The severity of PONV, evaluated by the number of emetic episodes per patient (1.59+/-1.90 vs 0.29+/-0.66; P = 0.0029), and the rescue antiemetic requirement (59.2% vs 14.8%; P = 0.0019) was significantly lower, in the ondansetron group. Patient satisfaction scores and number needed to prevent PONV (2.07) were significantly better and therapeutically more favorable in the ondansetron group. The incidence of adverse events such as headache, dizziness, and increased liver enzyme levels (number needed to harm = infinity) was similar in both groups. Administered at the end of the surgery in adult female patients undergoing general anesthesia for MRM, ondansetron 4 mg is effective and safe in preventing PONV. We recommend the clinical practice of routine prophylactic ondansetron to prevent PONV after MRM, as it significantly improves perioperative patient satisfaction and outcome. ⋯ We evaluated the antiemetic efficacy, safety, and routine use of prophylactic ondansetron, a "gold standard" antiemetic, in women undergoing radical breast surgery who were at a high risk of postoperative vomiting. We analyzed more meaningful "true" and "therapeutic" outcome measures, and we conclude that prophylactic ondansetron is safe and effective and that its routine use is justified.