Intrathecal ropivacaine 5 mg/ml for outpatient knee arthroscopy: a comparison with lidocaine 10 mg/ml.

PURPOSE: The aim of this prospective, randomised, blind study was to compare the evolution of spinal block produced with 50 mg lidocaine 10 mg/ml and 10 mg ropivacaine 5 mg/ml for outpatient knee arthroscopy. METHODS: Thirty outpatients undergoing knee arthroscopy received 50 mg of lidocaine 10 mg/ml (n=15) or 10 mg of ropivacaine 5 mg/ml (n=15) intrathecally. The evolution of spinal block was recorded until home discharge, while the occurrence of transient neurologic symptoms (TNS) was evaluated through phone-call follow-ups. RESULTS: The median onset time was 15 (10-21) min with lidocaine and 24 (11-37) min with ropivacaine (P=0.109). Spinal lidocaine resulted in a faster resolution of sensory block [148 (130-167) min vs. 188 (146-231) (P=0.022)], unassisted ambulation with crutches [176 (144-208) min vs. 240 (179-302) min (P=0.014)], and voiding [208 (163-254) min vs. 293 (242-343) min (P=0.001)] than ropivacaine. Recovery of motor function required 113 (95-131) min with lidocaine and 135 (87-183) with ropivacaine (P=0.219). Six lidocaine patients reported TNS (40%) as compared with no patient receiving ropivacaine (0%) (P=0.005). CONCLUSIONS: Spinal block produced with 10 mg ropivacaine 5 mg/ml is as effective as that produced by 50 mg of lidocaine 10 mg/ml. Recovery of unassisted ambulation and spontaneous voiding occurred earlier with lidocaine, but this was associated with a markedly higher incidence of TNS.

Continuous lumbar epidural infusion of levobupivacaine: effects of small-or large-volume regimen of infusion.

BACKGROUND: The question of whether the dose, concentration or volume of a local anesthetic solution is the relevant determinant of the spread and quality of post-operative epidural analgesia is still open. In this prospective, randomized, double-blind study, we compared the effects of a large volume-low concentration with a small-volume-high-concentration lumbar epidural infusion of levobupivacaine. METHODS: Seventy patients scheduled for total hip replacement were enrolled. After surgery, patients were randomly allocated to receive a continuous epidural infusion of levobupivacaine (10.5 mg/h) using either 0.125% levobupivacaine infused at 8.4 ml/h (low concentration group, n=35) or 0.75% levobupivacaine infused at 1.4 ml/h (high concentration group, n=35). We blindly recorded the degree of pain relief at rest and during movement every 8 h for the first two post-operative days, as well as hip flexion, motor block, rescue analgesic consumption and adverse events. RESULTS: No difference in pain relief was observed between groups as estimated with the areas under the curve of the verbal Numerical Rating Scale for pain over time, both at rest and during movement. Similarly, there was no difference between groups in hip flexion degree, motor blockade and hemodynamic stability. CONCLUSIONS: Continuous lumbar epidural infusion of 0.75% levobupivacaine was as effective as continuous lumbar epidural infusion of 0.125% levobupivacaine, when administered at the same hourly dose of 10.5 mg, in achieving adequate analgesia both at rest and during movement, without differences in the incidence of hypotension and motor blockade.

Intrathecal atropine to prevent postoperative nausea and vomiting after Cesarean section: a randomized, controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common adverse effect of intrathecal morphine, especially after Cesarean section. This randomized controlled trial investigated the effects of intrathecal administration of a small-dose of atropine on postoperative nausea and vomiting after Cesarean section. METHODS: Parturients with ASA physical status class I-II scheduled for elective Cesarean section and consenting to spinal anesthesia were enrolled. They received 0.5% hyperbaric bupivacaine 12.5 mg, morphine 200 µg and one of the following three solutions: atropine 100 µg intrathecally and saline intravenously; saline intrathecally and atropine 100 µg intravenously; saline only both intravenously and intrathecally. We examined the incidence and severity of PONV, pain ratings and the need for analgesics. RESULTS: We followed 204 parturients. The incidence of PONV was 15%, 37% and 49% in the three groups, respectively (P<0.001). The relative risk reduction for PONV when using intrathecal atropine was 69% vs. placebo and 59% vs. intravenous atropine. No differences were noted in terms of postoperative pain. CONCLUSION: Intrathecal atropine had a significant antiemetic effect, making it a useful adjunct for intrathecal opioid-related PONV.

Transcutaneous carbon dioxide monitoring in spontaneously breathing, nonintubated patients in the early postoperative period.

BACKGROUND: The authors investigated the accuracy of transcutaneous capnometry (TcPCO(2)) in estimating arterial blood carbon dioxide partial pressure (PaCO(2)) during spontaneous breathing in patients admitted to our surgical intensive care unit (ICU). METHODS: Serial TcPCO(2) and PaCO(2) measurements were taken in stable patients undergoing postoperative monitoring after major abdominal, vascular, or thoracic surgery. Patients were enrolled 12 hours after extubation. Exclusion criteria were pulmonary dysfunction, hemodynamic instability, or anemia. Linear regression, mixed models, and Bland-Altman analyses were used to compare accuracy and correlation between the two variables. Data are presented as means (95% confidence intervals). RESULTS: PaCO(2) values ranged between 26 mmHg and 52 mmHg. Mean values for TcPCO(2) and PaCO(2) were 35.3 (33.8-36.8) mmHg and 39.2 (37.6-40.7) (P<0.001). Bland-Altman analysis showed a bias of -3.8 (-5.1-2.5) mmHg with upper and lower limits of agreement of 5.6 (3.4-7.9) mmHg and -13.3 (-15.6 -11.1) mmHg, respectively. Thirty-one (55.4%) measurements disagreed by 3 mmHg or more. Linear mixed model analysis with adjustment for repeated measurements showed low correlation (r=0.63; P<0.0005). There were small but significant differences between patients in the correlation coefficient (P=0.04). CONCLUSION: TcPCO(2) showed moderate bias with wide limits of agreement when compared to PaCO(2) in our patients. The regression model showed low correlation of the measurements when adjusting for repeated measurements and between-subject variances. TcPCO(2) may not provide an accurate quantitative estimation of PaCO(2) in stable, spontaneously breathing, nonintubated patients in the early postoperative period.