Anesthesiology
-
Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of 0.5% ropivacaine and 0.5% bupivacaine for epidural anesthesia in patients undergoing lower-extremity surgery.
Ropivacaine is an amide local anesthetic structurally related to, but appearing less cardiotoxic, than bupivacaine. The authors' investigation was designed in a randomized, double-blind fashion to compare the clinical effectiveness of ropivacaine and bupivacaine in patients undergoing lower-extremity surgery. Forty-five patients were randomized to receive 20 ml of 0.5% ropivacaine or bupivacaine. ⋯ Cardiovascular changes, incidence of tourniquet pain, and the amounts of supplemental medications necessary were also similar between groups. The authors found 0.5% ropivacaine and bupivacaine to be clinically similar in both sensory- and motor-blocking characteristics, with the exception that bupivacaine produced a blockade of slightly longer duration. Because ropivacaine is reported to be less cardiotoxic than bupivacaine in animal studies, the similarity of clinical epidural anesthesia may make ropivacaine the preferred agent.
-
The present study evaluated responses to train-of-four (TOF) stimulation at a range of stimulating currents. Traditionally TOF has been applied with a supramaximal stimulus but this may be quite uncomfortable for the awake patient. In the first part of this study, 12 healthy volunteers quantified (by 10-cm visual analog scale) the discomfort associated with TOF stimulation at 20, 30, and 50 mA. ⋯ Although single twitch heights increased significantly as amperage was increased, there was no statistical difference in the T4/T1 ratios at the three different currents. The mean +/- SD T4/T1 ratios at 20, 30, and 50 mA were 0.795 +/- 0.247, 0.798 +/- 0.237, and 0.802 +/- 0.233, respectively (P = ns). It is concluded that TOF monitoring using a submaximal stimulus is more comfortable for the awake patient who is suspected of residual weakness, and that T4/T1 testing can be reliably accomplished intraoperatively as well as postoperatively using submaximal stimuli.
-
Randomized Controlled Trial Comparative Study Clinical Trial
A comparison between bupivacaine instillation versus ilioinguinal/iliohypogastric nerve block for postoperative analgesia following inguinal herniorrhaphy in children.
This study compared the postoperative pain relief provided by simple instillation of bupivacaine into a hernia wound with that provided by ilioinguinal/iliohypogastric (IG/IH) nerve block. Sixty children undergoing inguinal hernia repair under general anesthesia were randomized to receive 0.25 ml/kg of 0.25% bupivacaine for either IG/IH nerve block or up to 0.5 ml/kg of the same solution for instillation nerve blocks. In the postanesthesia care unit (PACU), a trained blinded observer evaluated the patient's level of postoperative pain using a standardized 10-point objective pain scale. ⋯ The two groups were not significantly different in age, duration of surgery, or anesthesia. There was no significant difference between patients who received the two treatment modalities in their pain scores, analgesic requirements in the PACU, recovery times, and discharge times. These results demonstrate that the simple instillation of local anesthetics into a wound provides postoperative pain relief following hernia repair, which is as effective as that provided by intraoperative IG/IH nerve block.
-
Randomized Controlled Trial Comparative Study Clinical Trial
A double-blind assessment of segmental sensory changes with epidural fentanyl versus epidural saline in patients undergoing extracorporeal shock-wave lithotripsy.
Segmental changes to pin prick and cold stimuli were tested in a double-blind manner in pain-free patients scheduled for extracorporeal shockwave lithotripsy (ESWL). Fifty patients were randomly allocated to receive either epidural fentanyl (100 micrograms in 10 ml normal saline) or 10 ml epidural normal saline. In a further 25 patients an epidural catheter was inserted but no solution injected. ⋯ There were no significant differences between fentanyl and normal saline groups in the number of patients reporting sensory changes to pin prick, rate of onset of these changes, or segmental level. For cold stimuli, more patients in the fentanyl group than in the normal saline group reported a change (16 vs. 8; P = 0.02) but the segmental level was similar. The effect of normal saline as a diluent in epidurally administered opioids may be of clinical importance.
-
Randomized Controlled Trial Clinical Trial
Continuous epidural infusion of 0.0625% bupivacaine-0.0002% fentanyl during the second stage of labor.
A randomized, double-blind, placebo-controlled study was performed to evaluate the analgesic efficacy and influence of continuing an epidural infusion of 0.0625% bupivacaine-0.0002% fentanyl during the second stage of labor in nulliparous women. When the cervix was fully dilated, coded study solution was substituted for the known bupivacaine-fentanyl solution. The study solution for 29 patients was 0.0625% bupivacaine-0.0002% fentanyl; 34 patients received saline placebo. ⋯ Among the women who delivered vaginally, eleven of 28 (39%) women in the bupivacaine-fentanyl group, versus five of 34 (15%) in the saline-placebo group, had surgical perineal anesthesia for vaginal delivery (P less than .05). Six of 28 (21%) women in the bupivacaine-fentanyl group, and five of 34 (15%) in the saline-placebo group, underwent instrumental vaginal delivery (P = NS). The median duration of the second stage of labor was 53 min (range = 5-283) in the bupivacaine-fentanyl group, and 63 min (range = 16-181) in the saline-placebo group (P = NS).(ABSTRACT TRUNCATED AT 250 WORDS)