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Study Objective: To evaluate the efficacy of three different concentrations of ropivacaine (0.5%, 0.75%, and 1%) together with a single concentration of hyaluronidase administered for peribulbar block., Design: Prospective, randomized, double-blind study., Setting: Anesthesia department of a university teaching hospital., Patients: 68 ASA physical status I, II, and III patients undergoing elective cataract surgery., Interventions: Patients were randomly allocated to receive peribulbar block with 6.5 mL of either 0.5% (Group Ropi-5; n = 22), 0.75% (Group Ropi-7.5; n = 22), or 1% ropivacaine (Group Ropi-10; n = 24). In all patients, 0.5 mL of hyaluronidase was added to the local anesthetic solution., Measurements and Main Results: A larger proportion of patients in Groups Ropi-7.5 (82%) and Ropi-10 (83%) showed complete motor block 15 minutes after injection compared with Group Ropi-5 (55%;p = 0.05, andp = 0.03, respectively). Hypotension (reduction of systolic blood pressure by 30% or more from baseline) was observed in two Group Ropi-5 patients (9%), and two Group Ropi-7.5 patients (9%;p = 0.31), whereas bradycardia (reduction in heart rate < or = 50 bpm) was observed in one Group Ropi-5 patient (4%), and three Group Ropi-10 patients (12%;p = 0.18). Seven hours after surgery, a smaller proportion of Group Ropi-10 patients (64%) showed complete recovery of sensory function as compared with both Group Ropi-5 (94%) and Group Ropi-7.5 (90%;p = 0.03 and p = 0.03, respectively). Complete recovery of motor function 1 hour after surgery was more frequent in Group Ropi-5 (37%) than in Group Ropi-7.5 (5%) or Group Ropi-10 (9%;p = 0.05 and p = 0.05, respectively); however, no other differences in recovery of motor function were observed at any other observation times, with complete recovery in all patients 7 hours after surgery., Conclusions: While confirming that ropivacaine is a good option for peribulbar anesthesia, this study demonstrated that the use of 0.75% or 1% concentrations are preferred in that they produce quick and deep sensory and motor block of the operated eye. If recovery of normal motor function is important after surgery, the 0.75% concentration probably represents the best compromise.

Study Objective: To compare the onset time and duration of epidural anesthesia, and the quality of postoperative analgesia produced by levobupivacaine, racemic bupivacaine, and ropivacaine., Design: Prospective, randomized, double-blinded study., Setting: Inpatient anesthesia at a University Hospital., Patients: 45 ASA physical status I, II, and III patients, undergoing elective total hip replacement., Interventions: After standard intravenous midazolam premedication and infusion of 500 mL of Ringer's acetate solution, patients were randomly allocated to receive epidural block with 0.5% levobupivacaine (n = 15), 0.5% bupivacaine (n = 15), or 0.5% ropivacaine (n = 15). Postoperatively, after pinprick sensation recovered at T(t), a patient-controlled epidural infusion was provided with 0.125% levobupivacaine, 0.125% bupivacaine, or 0.2% ropivacaine, respectively (baseline infusion rate 5 mL/hr; incremental bolus 2 mL, lockout time: 20 min). Intravenous ketoprofen was also available for rescue analgesia if required., Measurements and Main Results: The onset time of sensory block was 31 +/- 16 minutes with levobupivacaine, 25 +/- 19 minutes with bupivacaine, and 30 +/- 24 minutes with ropivacaine (p = 0.98), after a median (range) volume of 15 (10-18) mL in Group Levobupivacaine, 14 (10-18) mL in Group Bupivacaine, and 15 (10-18) mL in Group Ropivacaine (p = 0.85). Six patients in the ropivacaine group (40%) showed an intraoperative Bromage score <2 as compared with only three patients of Group Levobupivacaine (20%) and no patient of Group Bupivacaine (p = 0.02). Recovery of pinprick sensation at T(t) occurred after 214 +/- 61 minutes with levobupivacaine, 213 +/- 53 minutes with bupivacaine, and 233 +/- 34 minutes with ropivacaine (p = 0.26). A similar degree of pain relief was observed in the three groups without differences in local anesthetic consumption and need for rescue analgesia. Motor blockade progressively resolved without differences among the three groups., Conclusions: Levobupivacaine 0.5% produces an epidural block of similar onset, quality, and duration as the one produced by the same volume of 0.5% bupivacaine, with a motor block deeper than that produced by 0.5% ropivacaine. When prolonging the block for the first 12 hours after surgery with a patient-controlled epidural infusion, 0.125% levobupivacaine provides adequate pain relief after major orthopedic surgery, with similar recovery of motor function as compared with 0.125% bupivacaine and 0.2% ropivacaine.

Study Objective: To compare the intraoperative and postoperative clinical properties of the sciatic nerve block performed with either 0.5% bupivacaine or 0.5% levobupivacaine for orthopedic foot procedures., Design: Randomized, double-blind study., Setting: Inpatient unit of a university-affiliated hospital., Patients: 30 ASA physical status I and II patients undergoing elective hallux valgus repair under regional anesthesia., Interventions: After administering intravenous (IV) midazolam premedication (0.05 mg/kg), a femoral nerve block was performed with 15 mL of mepivacaine 2%. Patients were then randomly allocated to receive, in a double-blind fashion, a sciatic nerve block with 20 mL of either 0.5% bupivacaine (n = 15) or 0.5% levobupivacaine (n = 15)., Measurements and Main Results: An observer who was blinded to the study drug recorded the onset time, quality, and duration of the sciatic nerve block. Postoperative analgesia consisted of 100 mg IV ketoprofen every 8 hours, with the first administration given at the patient's request. Mean (+/-SEM) onset time of the sciatic nerve block was 35 +/- 5 minutes for bupivacaine and 31 +/- 6 minutes for levobupivacaine (p = not significant [NS]). The duration of motor and sensory blocks with bupivacaine was 761 +/- 112 minutes and 790 +/- 110 minutes, respectively, and 716 +/- 80 minutes and 814 +/- 73 minutes, respectively, with levobupivacaine (p = NS). The first pain medication was requested after 844 +/- 96 minutes with bupivacaine and 872 +/- 75 minutes after levobupivacaine (p = NS). No differences in the quality of nerve block and patient satisfaction were reported between the two groups., Conclusions: A dose of 20 mL of 0.5% levobupivacaine induces sciatic nerve block of similar onset, duration, and intensity as the block produced by the same volume and concentration of the racemic solution of bupivacaine.

Objective: To evaluate the changes in hemodynamic variables and intraocular pressure (IOP) after tracheal intubation using either lightwand or direct-vision laryngoscopy techniques., Design: Prospective, randomized study., Setting: Inpatient anesthesia at a University Anesthesia Department., Patients: 50 normotensive, ASA physical status I and II patients, without ocular or cardiovascular diseases, and with a Mallampati score no greater than 2., Interventions: After intravenous (i.v.) midazolam premedication (0.05 mg.kg-1), general anesthesia was induced with fentanyl (1 microgram.g-1) and thiopental sodium (5 mg.g-1) followed by vecuronium bromide (0.1 mg.g-1), then patients were randomly allocated to receive either the lightwand (Trachlight, n = 25) or direct-vision laryngoscopy (Laryngoscopy, n = 25) intubating techniques. General anesthesia was maintained with 1% isoflurane and 60% nitrous oxide in oxygen mixture for 5 minutes., Measurements and Main Results: Baseline hemodynamic variables were recorded 10 minutes after i.v. premedication, and then every minute after tracheal intubation. Intraocular pressure measurements were performed by means of a computerized indentation tonometer after general anesthesia induction and then 1 and 5 minutes after tracheal intubation. In both groups, mean arterial blood pressure and heart rate increased from baseline, without differences between the two groups. One minute after intubation, IOP increased in both groups: the mean percentage increase was 32% in the Laryngoscopy group and 16% in the Trachlight group. However, this difference was not statistically significant. Five minutes after intubation, IOP decreased to baseline values in both groups., Conclusion: We conclude that in healthy patients without ocular disease, using a lightwand intubating technique does not reduce the hemodynamic responses and increase in IOP associated with tracheal intubation as compared with conventional direct-vision laryngoscopy.