Anesthesia and analgesia
-
Anesthesia and analgesia · Aug 1992
Randomized Controlled Trial Clinical TrialEffects of ketorolac and bupivacaine on recovery after outpatient arthroscopy.
The effects of intraarticular bupivacaine, systemic ketorolac, and a combination of both treatments on postoperative pain and mobilization were evaluated in 60 healthy outpatients undergoing arthroscopic knee surgery under general anesthesia. After induction of anesthesia, patients received 2 mL of either ketorolac (60 mg) or saline solution (1 mL IV and 1 mL IM). On completion of surgery, the patient's knee joint was injected with 30 mL of either 0.5% bupivacaine or saline solution, according to a randomized, double-blind protocol. ⋯ Similarly, there were no differences in the times to ambulation or discharge or in analgesic requirements at home. In conclusion, a combination of systemic ketorolac and intraarticular bupivacaine decreased analgesic requirements and pain on awakening after arthroscopic surgery. However, the use of ketorolac alone or in combination with bupivacaine offered no advantage over bupivacaine alone with respect to recovery times after outpatient arthroscopy.
-
Anesthesia and analgesia · Aug 1992
Randomized Controlled Trial Comparative Study Clinical TrialEsmolol is more effective than sodium nitroprusside in reducing blood loss during orthognathic surgery.
The goal of this study was to compare the efficacy of esmolol and sodium nitroprusside (SNP) as primary drugs for producing controlled hypotension and limiting blood loss during orthognathic surgery. Thirty ASA physical status I and II patients (mean age 22 yr) undergoing LeFort I maxillary osteotomies were randomly assigned to receive either esmolol (n = 15) or SNP (n = 15) as the primary drug to induce hypotension. ⋯ The mean arterial blood pressure during the hypotensive period was 58.7 +/- 0.7 (mean +/- SEM) and 61.8 +/- 0.4 mm Hg for esmolol and SNP, respectively (P less than 0.001). In addition, 40% +/- 4% of the observed values in the esmolol group and 53% +/- 3% in the SNP group were outside the target range for mean arterial blood pressure (difference significant at P less than 0.05), and a greater proportion of the deviations were above 65 mm Hg in the SNP group than in the esmolol group (0.64 vs 0.46, respectively, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
-
Anesthesia and analgesia · Aug 1992
Randomized Controlled Trial Clinical TrialContinuous low-dose 3-in-1 nerve blockade for postoperative pain relief after total knee replacement.
We have investigated the value of a 3-in-1 nerve block, followed by a continuous low-dose infusion of bupivacaine into the femoral nerve sheath for postoperative analgesia after total knee replacement. Thirty-seven patients were randomly allocated to either a control group or a study group. The study group had a catheter placed in the ipsilateral femoral nerve sheath. ⋯ This was followed by a continuous infusion of 0.125% bupivacaine at 6 mL/h. The study group had significantly lower pain scores 4 and 24 h postoperatively (P less than 0.01) and required less postoperative opioid analgesic medication (P less than 0.01) than the control group. The authors conclude that a continuous low-dose infusion into the femoral nerve sheath results in better pain relief than conventional intramuscularly administered narcotics after total knee arthroplasty.
-
Anesthesia and analgesia · Aug 1992
Effects of hypocarbia on the pharmacodynamics of sufentanil in humans.
Descriptors of power and frequency derived from power spectral analysis of the electroencephalogram (EEG) were used to determine the effects of low-dose sufentanil (0.1 micrograms/kg) on brain activity. The effects of hypocarbia alone and of hypocarbia with sufentanil in patients receiving a N2/O2 (70%:30%) anesthetic were also studied. ⋯ When the anterior EEG montages from the two groups that received sufentanil were compared, the delta power band, spectral edge 50 (median power frequency), and the relative power in the delta power band divided by the alpha plus beta power bands [D/(A + B)] in the hypocarbic group exhibited a significantly greater shift of power into the lower frequency range. It is concluded that (a) power spectral analysis is a sensitive measure of the effects of hypocarbia and small doses of sufentanil on the brain; (b) the power spectral analysis descriptors--delta power band, spectral edge 50, and [D/(A + B)]--are statistically the most sensitive to EEG changes induced by sufentanil; and (c) hypocarbia intensifies patient EEG response to sufentanil, as judged by changes in EEG descriptors.
-
Anesthesia and analgesia · Aug 1992
Pressure support ventilation decreases inspiratory work of breathing during general anesthesia and spontaneous ventilation.
Spontaneous ventilation may offer advantages over controlled mechanical ventilation (CMV), but increase in work of breathing may diminish its usefulness. During general anesthesia, respiratory depression and increased work of breathing often preclude spontaneous ventilation, and patients then receive CMV. We compared the inspiratory work of breathing of anesthetized patients who breathed with pressure support ventilation (PSV) with that associated with a demand gas flow and a standard anesthesia circle system. ⋯ The inspiratory work of breathing was calculated as the integral of the area subserved by a plot of esophageal pressure and tidal volume during inspiration. Heart rate and mean arterial blood pressure were recorded, and arterial blood was sampled for gas tension and pH analysis. No differences were found in pHa, Paco2, Pao2, tidal volume, respiratory rate, heart rate, or mean arterial blood pressure among the three modes of ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)