Anesthesia and analgesia
-
Anesthesia and analgesia · Jul 2000
Randomized Controlled Trial Comparative Study Clinical TrialExtended "three-in-one" block after total knee arthroplasty: continuous versus patient-controlled techniques.
This prospective, randomized, double-blinded study assessed the efficacy of patient-controlled analgesia (PCA) techniques for extended "3-in-1" block after total knee arthroplasty. A total of 45 patients were divided into three groups of 15. Over 48 h, all patients received 0.125% bupivacaine with 1 microg/mL clonidine via a femoral nerve sheath catheter in the following manner: as a continuous infusion at 10 mL/h in Group 1; as a continuous infusion at 5 mL/h plus PCA boluses (2.5 mL/30 min) in Group 2; or as PCA boluses only (10 mL/60 min) in Group 3. Pain scores, sensory block, supplemental analgesia, bupivacaine consumption, side effects, and satisfaction scores were recorded. Pain scores and supplemental analgesia were comparable in the three groups. Bupivacaine consumption was significantly less in Groups 2 and 3 than in Group 1 (P < 0.01), and in Group 3 than in Group 2 (P < 0.01). Side effects and satisfaction were comparable in the three groups. We conclude that extended "3-in-1" block provides efficient pain relief after total knee arthroplasty and that, compared with a continuous infusion, PCA techniques reduce the local anesthetic consumption without compromise in patient satisfaction or visual analog scale scores. Of the two PCA techniques tested, PCA boluses (10-mL lockout; time, 60 min) of 0.125% bupivacaine with 1 microg/mL clonidine was associated with the smallest local anesthetic consumption, and is, therefore, the recommended extended "3-in-1" block technique. ⋯ We demonstrated that, after total knee arthroplasty, an extended "3-in-1" block consisting of patient-controlled analgesia boluses (10 mL/60 min) of 0.125% bupivacaine with 1 microg/mL clonidine provides efficient postoperative analgesia and significantly minimizes local anesthetic consumption.
-
Anesthesia and analgesia · Jul 2000
Randomized Controlled Trial Comparative Study Clinical TrialCaruncle single injection episcleral (Sub-tenon) anesthesia for cataract surgery: mepivacaine versus a lidocaine-bupivacaine mixture.
We compared the quality of anesthesia provided by mepivacaine 2% or a mixture of lidocaine 2%-bupivacaine 0.5%, both with hyaluronidase, in caruncle single-injection episcleral (sub-Tenon) anesthesia. Sixty patients undergoing cataract surgery were included in this randomized, double-blinded study. The time to the onset of blockade, maximal akinesia, need for supplemental injection, and time to recovery were recorded. With mepivacaine, the time to onset was slightly shorter, and the akinesia score higher, than with the mixture. Although statistically significant, these differences are small. With mepivacaine, the time to recovery was shorter. We conclude that the reproducible short duration of the block may be an advantage in outpatient surgery. ⋯ We compared the classic mixture of lidocaine 2% plus bupivacaine 0.5% to mepivacaine 2% for caruncle episcleral (sub-Tenon) anesthesia for cataract surgery. Mepivacaine provided a more efficient block with a quicker onset and a quicker recovery. However, these differences were very small and were of little clinical interest.
-
Anesthesia and analgesia · Jul 2000
Meta Analysis Comparative StudySevoflurane versus propofol for anesthetic induction: a meta-analysis.
We performed this meta-analysis to compare the characteristics of sevoflurane and propofol for the induction of routine anesthesia and for laryngeal mask airway (LMA) insertion. The variables assessed were 1) time to loss of consciousness, 2) incidence of apnea during induction, 3) induction complications, 4) time for successful LMA insertion, 5) success with LMA insertion on first attempt, 6) patient dissatisfaction, and 7) postoperative nausea and vomiting. MEDLINE, Embase, and the Cochrane library databases between January 1992 and October 1999 were reviewed for randomized, controlled trials comparing anesthetic induction between sevoflurane/nitrous oxide and propofol. Data from the 12 randomized, controlled studies were used for the meta-analysis. Sevoflurane induction was associated with a trend toward higher patient dissatisfaction and higher first-time success with LMA. Apnea was less common in the sevoflurane group. The incidence of postoperative nausea and vomiting was significantly more frequent in the sevoflurane group (P < 0.05). This effect was still present when all other variables, except the induction methods, were controlled. The other pooled variables did not show a significant difference between sevoflurane and propofol. Sevoflurane and propofol had similar efficacy for anesthetic induction. However, for routine outpatient surgery, propofol may still be the preferred induction anesthetic because of its favorable induction of anesthesia characteristics, high patient satisfaction, and less frequent incidence of postoperative nausea and vomiting. ⋯ Sevoflurane and propofol had similar efficacy for anesthetic induction. However, for routine outpatient surgery, propofol may still be the preferred induction anesthetic because of its favorable induction of anesthesia characteristics, high patient satisfaction, and less frequent incidence of postoperative nausea and vomiting.
-
Anesthesia and analgesia · Jul 2000
Randomized Controlled Trial Clinical TrialInterpleural analgesia does not influence postthoracotomy pain.
The management of postthoracotomy pain is a problem and may contribute to atelectasis, leading to hypoxemia, pulmonary infection, and permanent alveolar damage. We sought to determine the efficacy of interpleural analgesia for pain control and to evaluate independent predictors for postoperative pain intensity. Eighty-three patients undergoing elective anterolateral (n = 37) and posterolateral (n = 46) thoracotomy were included in a prospective, randomized, double-blinded trial. Patients were assigned to receive either 0.5% bupivacaine or saline solution interpleurally every 4 h for 10 doses postoperatively. All patients also received patient-controlled analgesics (PCA) with piritramide as the opioid for additional pain control. Pain was assessed on the basis of PCA requirements and by using a visual analog scale. Visual analog scale scores and PCA requirements were not different between groups. Both interpleural bupivacaine and saline significantly reduced pain scores 30 min after the administration. We concluded that pain reduction by interpleural instillation of bupivacaine reflects a placebo-like effect; however, interpleural analgesia is not effective in patients undergoing lateral thoracotomy. Sex and surgical approach were shown to influence postoperative pain intensity at rest, but not during coughing. The female patients, and those undergoing posterolateral thoracotomy, exhibited higher pain scores. This observation appears to be of only marginal clinical significance. The efficacy of interpleural analgesia to reduce postoperative pain intensity in patients after lateral thoracotomy is controversial. In this study we demonstrated a lack of efficacy of interpleural analgesia. ⋯ The efficacy of interpleural analgesia to reduce postoperative pain intensity in patients after lateral thoracotomy is controversial. In this study, we demonstrated a lack of efficacy of interpleural analgesia.
-
Anesthesia and analgesia · Jul 2000
Randomized Controlled Trial Comparative Study Clinical TrialCerebral hemodynamic response to the introduction of desflurane: A comparison with sevoflurane.
Rapid increases in the inspired concentration of desflurane cause transient increases in heart rate and blood pressure. Desflurane also impairs cerebral autoregulation at clinical concentrations. Sevoflurane does not share these hemodynamic side effects. We compared the cerebral and systemic hemodynamic responses to the introduction of desflurane or sevoflurane after the induction of anesthesia with propofol. Twenty healthy adult patients scheduled for nonneurological surgery were recruited. After the induction of anesthesia with propofol, either desflurane or sevoflurane (n = 10 per group) was introduced at 7.2% or 2.2%, respectively, and increased to 10.8% or 3.3%, respectively, 2 min later. Middle cerebral artery blood flow velocity was measured continuously by using a 2-MHz transcranial Doppler ultrasound probe. Heart rate and blood pressure were recorded at 1-min intervals during the 12-min study period. Those patients receiving desflurane had significantly greater middle cerebral artery blood flow velocities, heart rates, and blood pressures than those receiving sevoflurane (P < 0.01). ⋯ The introduction of desflurane after the induction of anesthesia leads to significant disturbances in cerebral and systemic hemodynamics suggesting loss of cerebral autoregulation and cerebral hyperemia. This may have implications for patients undergoing anesthesia for intracranial surgery.