Anesthesia and analgesia
-
Anesthesia and analgesia · Feb 2002
The effects of the simulated Valsalva maneuver, liver compression, and/or Trendelenburg position on the cross-sectional area of the internal jugular vein in infants and young children.
We calculated the effects of the simulated Valsalva (V), liver (L) compression, and Trendelenburg (T) position on the cross-sectional area (CSA) of the right internal jugular vein by using planimetry (Aloka ultrasound machine) in 84 infants and young children. Eight combinations of positions and interventions were studied for each patient, with the patient supine, in the T position, during the simulated V maneuver, with L compression and a combination of maneuvers. Data were analyzed by using Friedman's chi(2) test and Wilcoxon's signed rank test. An increase of >25% in the CSA of the internal jugular vein was considered significant. In infants, the maximal mean increase achieved with the combination of all 3 maneuvers was only 17.4% +/- 16.1%. As a single maneuver, the simulated V was the most effective (11.6% +/- 11.5%). In children, the combination of all 3 maneuvers performed simultaneously produced a mean 65.9% (SD +/- 44.7%) increase in the CSA, which was larger than the increase by all other maneuvers alone or in a single combination (Friedman's test, P < 0.001 and Wilcoxon's test, P < 0.002). As a single maneuver, V produced the most increase (40.4% +/- 32.2%) compared with L compression (14.3% +/- 18.9%) or T position (24.3% +/- 27.1%). ⋯ The combinations of simulated Valsalva, liver compression, and Trendelenburg maneuvers produce the maximal mean increase in the size of the internal jugular vein in infants and young children, with the Valsalva maneuver being the most effective single maneuver. This increase is significant in young children, but negligible in infants.
-
Anesthesia and analgesia · Feb 2002
Randomized Controlled Trial Multicenter Study Clinical TrialThe efficacy and safety of three concentrations of levobupivacaine administered as a continuous epidural infusion in patients undergoing orthopedic surgery.
We evaluated the efficacy and safety of three concentrations of levobupivacaine infused epidurally as analgesia for patients undergoing orthopedic procedures. Patients undergoing elective hip or knee joint replacement were enrolled in the study (n = 105). Sensory blockade was established preoperatively with 10-15 mL of 0.75% levobupivacaine. Patients were then randomized to receive 0.0625%, 0.125%, or 0.25% levobupivacaine as a continuous epidural infusion at 6 mL/h for 24 h. IV morphine patient-controlled analgesia was given as rescue analgesia, and time to first request for analgesia and total dose of morphine consumed were recorded. Sensory blockade, motor blockade, visual analog scale pain score, and cardiovascular variables were also recorded at regular intervals postoperatively. Ninety-one patients were included in the primary intent-to-treat analysis. Total normalized dose of morphine, number of patient-controlled analgesia requests, and overall postoperative visual analog scale pain scores were significantly lower for the 0.25% group compared with the other two groups, and the time to first request for rescue analgesia was longer. There was no significant difference between the 0.125% and 0.25% groups in terms of maximum motor blockade achieved and time to minimal motor blockade. Safety data were equivalent among the three groups. We conclude that levobupivacaine as a continuous epidural infusion provided adequate postoperative analgesia and that the 0.25% concentration provided significantly longer analgesia than 0.125% or 0.0625% levobupivacaine without any significant increase in detectable motor blockade relative to the 0.125% group. ⋯ Postoperative epidural infusion of levobupivacaine can provide safe and effective analgesia for patients having hip or knee joint replacement. Of the three concentrations we infused at a constant rate, 0.25% provided significantly better pain relief.
-
Anesthesia and analgesia · Feb 2002
Meta AnalysisPharmacological treatment of postoperative shivering: a quantitative systematic review of randomized controlled trials.
Shivering is a frequent complication in the postoperative period. The relative efficacy of interventions that are used for the treatment of postoperative shivering is not well understood. We performed a systematic search (MEDLINE, EMBASE, Cochrane Library, hand searching, all languages, to August, 2000) for full reports of randomized comparisons of any pharmacological antishivering intervention (active) with placebo (control) in the postoperative period. Dichotomous data on absence of further shivering after treatment and adverse effects were extracted from original reports. Relative risk (RR) and number-needed-to-treat (NNT) were calculated with 95% confidence interval (CI) using a fixed effect model. Data from 20 trials (944 adults received an active intervention, 413 were controls) were analyzed. Antishivering efficacy depended on the active regimen and the length of follow-up. Efficacy with meperidine 25 mg, clonidine 150 microg, ketanserin 10 mg, and doxapram 100 mg was reported in at least three trials; all were significantly more effective than control. After 1 min, the NNT of meperidine 25 mg for no further shivering compared with placebo was 2.7 (RR, 6.8; 95% CI, 2.5-18.5). After 5 min, the NNT of meperidine 25 mg was 1.3 (RR, 9.6; 95% CI, 5.7-16), the NNT of clonidine 150 microg was 1.3 (RR, 6.8; 95% CI, 3.3-14.2), the NNT of doxapram 100 mg was 1.7 (RR 4.0; 95% CI, 2.4-6.5), and the NNT of ketanserin 10 mg was 2.3 (RR 3.1; 95% CI, 1.9-5.1). After 10 min, the NNT of meperidine 25 mg was 1.5 (RR 4.0; 95% CI, 2.5-6.2). After 15 min, the NNT of ketanserin 10 mg was 3.3 (RR 1.5; 95% CI, 1.2-1.9). Long-term outcome data were lacking. There were not enough data for alfentanil, fentanyl, morphine, nalbuphine, lidocaine, magnesium, metamizol, methylphenidate, nefopam, pentazocine, and tramadol to draw meaningful conclusions. Reporting of adverse drug reactions was sparse. Fewer than two shivering patients need to be treated with meperidine 25 mg, clonidine 150 microg, or doxapram 100 mg for one to stop shivering within 5 min who would have continued to shiver had they all received a placebo. ⋯ Less than two shivering patients need to be treated with meperidine 25 mg, clonidine 150 microg, or doxapram 100 mg for one to stop shivering within 5 min who would have continued to shiver had they all received a placebo.
-
Anesthesia and analgesia · Feb 2002
Randomized Controlled Trial Comparative Study Clinical TrialParavertebral blockade for minor breast surgery.
Paravertebral blockade (PVB) has been advocated as a useful technique for breast surgery. We prospectively compared the efficacy of PVB via a catheter technique with the efficacy of general anesthesia (GA) for minor breast surgery. Thirty patients were randomized into two groups to receive either PVB or GA. Variables of efficacy were postoperative pain measured on a visual analog scale, postoperative nausea and vomiting (PONV), recovery time, and patient satisfaction. Postoperative visual analog scale scores in the PVB group were significantly lower in the early postoperative period (maximum, 12 vs 45 mm; P < 0.01). In both groups, PONV was nearly absent. There was no difference in recovery time. Patient satisfaction was better in the PVB group (2.8 vs 2.3; scale, 0-3; P < 0.01). There was one inadvertent epidural block and one inadvertent pleural puncture in the PVB group. Although PVB resulted in better postoperative pain relief, the advantages over GA were marginal in this patient group because postoperative pain was relatively mild and the incidence of PONV was small. Considering that the technique has a certain complication rate, we conclude that at present the risk/benefit ratio of PVB does not favor routine use for minor breast surgery. ⋯ This study confirms the previously reported superior pain relief after paravertebral blockade (PVB) for breast surgery. However, considering the relatively mild postoperative pain and therefore the limited advantage of PVB for these patients, the risk/benefit ratio does not favor the routine use of PVB for minor breast surgery.