Anesthesia and analgesia
-
Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Meta Analysis Comparative Study Clinical TrialThe comparative effects of postoperative analgesic therapies on pulmonary outcome: cumulative meta-analyses of randomized, controlled trials.
We performed meta-analyses of randomized, control trials to assess the effects of seven analgesic therapies on postoperative pulmonary function after a variety of procedures: epidural opioid, epidural local anesthetic, epidural opioid with local anesthetic, thoracic versus lumbar epidural opioid, intercostal nerve block, wound infiltration with local anesthetic, and intrapleural local anesthetic. Measures of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), vital capacity (VC), peak expiratory flow rate (PEFR), PaO2, and incidence of atelectasis, pulmonary infection, and pulmonary complications overall were analyzed. Compared with systemic opioids, epidural opioids decreased the incidence of atelectasis (risk ratio [RR] 0.53, 95% confidence interval [CI] 0.33-0.85) and had a weak tendency to reduce the incidence of pulmonary infections (RR 0.53, 95% CI 0.18-1.53) and pulmonary complications overall (RR 0.51, 95% CI 0.20-1.33). Epidural local anesthetics increased PaO2 (difference 4.56 mm Hg, 95% CI 0.058-9.075) and decreased the incidence of pulmonary infections (RR 0.36, 95% CI 0.21-0.65) and pulmonary complications overall (RR 0.58, 95% CI 0.42-0.80) compared with systemic opioids. Intercostal nerve blockade tends to improve pulmonary outcome measures (incidence of atelectasis: RR 0.65, 95% CI 0.27-1.57, incidence of pulmonary complications overall: RR 0.47, 95% CI 0.18-1.22), but these differences did not achieve statistical significance. There were no clinically or statistically significant differences in the surrogate measures of pulmonary function (FEV1, FVC, and PEFR). These analyses support the utility of epidural analgesia for reducing postoperative pulmonary morbidity but do not support the use of surrogate measures of pulmonary outcome as predictors or determinants of pulmonary morbidity in postoperative patients. ⋯ When individual trials are unable to produce significant results, it is often because of insufficient patient numbers. It may be impossible for a single institution to study enough patients. Meta-analysis is a useful tool for combining the data from multiple trials to increase the patient numbers. These meta-analyses confirm that postoperative epidural pain control can significantly decrease the incidence of pulmonary morbidity.
-
Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Comparative Study Clinical Trial0.125% ropivacaine is similar to 0.125% bupivacaine for labor analgesia using patient-controlled epidural infusion.
We compared the effects of 0.125% ropivacaine with 0.125% bupivacaine in laboring patients using patient-controlled epidural analgesia (PCEA). Fifty-one ASA physical status I or II term parturients with functioning epidural catheters were randomized to receive ropivacaine or bupivacaine using a prospective, double-blind design. Basal infusions (6 mL/h) were supplemented with patient-controlled boluses (5 mL) every 10 min as required. For inadequate analgesia, patients were administered 10-mL boluses of study solution until comfortable. There were no differences in verbal pain scores, amount of local anesthetics used, sensory levels, motor blockade, labor duration, mode of delivery, side effects, or patient satisfaction between the two local anesthetics. We conclude that 0.125% ropivacaine and bupivacaine are clinically indistinguishable and are both highly effective for labor analgesia using PCEA. ⋯ This study compared labor analgesia from 0.125% ropivacaine and 0.125% bupivacaine using patient-controlled epidural analgesia. We found no significant differences in local anesthetic use, analgesic characteristics, or side effects between 0.125% ropivacaine and 0.125% bupivacaine. We conclude that these two drugs are clinically indistinguishable at this concentration.
-
Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Clinical TrialAlfentanil as an adjuvant to epidural bupivacaine in the management of postoperative pain after laparotomies: lack of evidence of spinal action.
In this double-blind study, we compared the efficacy of epidural versus i.v. administration of alfentanil in combination with small-dose bupivacaine for postoperative pain relief. Thirty-two patients were randomly allocated to one of two study groups. Patients from both groups received an epidural loading dose of 60 mg of bupivacaine (12 mL of 0.5%). Subsequently, patients in the epidural (EPI) group received an infusion (8 mL/h) of 0.125% bupivacaine (10 mg/h) plus alfentanil (0.36 mg/h) and an i.v. infusion (8 mL/h) of NaCl 0.9%. Patients in the i.v. group received an epidural infusion (8 mL/h) of 0.125% bupivacaine (10 mg/h) and an i.v. infusion (8 mL/h) of alfentanil (0.36 mg/h). Infusions were maintained for 24 h. These dose regimens were such that equivalent subanalgesic plasma concentrations of alfentanil were obtained. Patient-controlled analgesia with morphine was available to both groups. Time to onset of postoperative pain and morphine consumption were used as variables to compare the two regimens. Measured plasma concentrations of alfentanil during the postoperative observation period were similar (< 20 ng/mL) in both groups. Median times to onset of postoperative pain (EPI 600 min, i.v. 360 min) and total morphine consumption (EPI 11 mg, i.v. 10 mg) did not differ between the groups (P > 0.2). We conclude that, in combination with epidural bupivacaine 0.125%, an i.v. infusion of alfentanil is equally effective as an epidural infusion of alfentanil if the plasma concentrations are the same. The study did not demonstrate a spinal mechanism of action for alfentanil. ⋯ This randomized, double-blind study showed that, when combined with small-dose bupivacaine (0.125%), epidurally administered alfentanil is not more effective than i.v. administered alfentanil for postoperative pain management when the regimens are such that equivalent subanalgesic plasma alfentanil concentrations are obtained. A spinal mechanism of action for alfentanil could therefore not be demonstrated.
-
Anesthesia and analgesia · Mar 1998
Randomized Controlled Trial Clinical TrialProphylactic ephedrine attenuates the hemodynamic response to propofol in elderly female patients.
In this study, we compared the effect of prophylactic administration of ephedrine against the hypotensive effect of propofol in elderly female patients scheduled for minor gynecological procedures. Ninety patients aged 60 yr or older were randomly allocated to one of three groups of 30 patients each to receive either normal saline, ephedrine 0.1 mg/kg, or ephedrine 0.2 mg/kg i.v. 1 min before the induction of anesthesia. Anesthesia was induced and maintained with propofol and fentanyl. Hemodynamic variables were measured before and 2, 5, 10, 15, 30, and 60 min after induction. The decrease in blood pressure and heart rate (HR) was significantly less in each of the ephedrine groups (P < 0.001). Furthermore, the decrease was less in the large-dose group compared with the small-dose group (P < 0.05). Twelve patients in the control group experienced a decrease in systolic blood pressure to < 80 mmHg, compared with only one patient in the ephedrine groups (P < 0.001). In conclusion, the prophylactic injection of ephedrine significantly attenuated, but did not completely abolish, the decrease in blood pressure associated with induction of anesthesia with fentanyl and propofol. Ephedrine 0.2 mg/kg was slightly more effective than ephedrine 0.1 mg/kg. ⋯ The prophylactic effect of ephedrine to counteract the hypotensive effect of propofol induction of anesthesia was investigated in three groups of elderly female patients given 0.1 or 0.2 mg of ephedrine or placebo before induction. Both ephedrine doses markedly attenuated, but neither of them abolished, the decrease in blood pressure.