Anesthesiology
-
Randomized Controlled Trial Comparative Study Clinical Trial
Hyperbaric spinal ropivacaine: a comparison to bupivacaine in volunteers.
Ropivacaine is a newly introduced local anesthetic that may be a useful alternative to low-dose bupivacaine for outpatient spinal anesthesia. However, its relative potency to bupivacaine and its dose-response characteristics are unknown. This double-blind, randomized, crossover study was designed to determine relative potencies of low-dose hyperbaric spinal ropivacaine and bupivacaine and to assess the suitability of spinal ropivacaine for outpatient anesthesia. ⋯ Ropivacaine is half as potent and in equipotent doses has a similar profile to bupivacaine with a higher incidence of side effects. Low-dose hyperbaric spinal ropivacaine does not appear to offer an advantage over bupivacaine for use in outpatient anesthesia.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Lumbar sympathetic blocks speed early and second stage induced labor in nulliparous women.
Rapid cervical dilation reportedly accompanies lumbar sympathetic blockade, whereas epidural analgesia is associated with slow labor. The authors compared the effects of initial lumbar sympathetic block with those of epidural analgesia on labor speed and delivery mode in this pilot study. ⋯ Nulliparous parturients having induced labor and receiving initial lumbar sympathetic blocks had faster cervical dilation during the first 2 h of analgesia, shorter second-stage labors, and a trend toward a lower dystocia cesarean delivery rate than did patients having epidural analgesia. The effects of lumbar sympathetic block on labor need to be determined in other patient groups. These results may help define the tocodynamic effects of regional labor analgesia.
-
Paralysis of the vocal cords is one objective of using relaxants to facilitate tracheal intubation. This study compares the neuromuscular blocking effect of succinylcholine and rocuronium on the larynx, the diaphragm, and the adductor pollicis muscle. ⋯ Neuromuscular blocking effect of muscle relaxants on the larynx can be measured noninvasively by electromyography. Although the larynx appears to be resistant to muscle relaxants, we could not demonstrate that its onset time differed from that of peripheral muscles.
-
Rapacuronium is a new nondepolarizing muscle relaxant with rapid onset and offset. As part of a study to determine its neuromuscular effects, the authors sampled plasma sparsely to determine the influence of age, gender, and other covariates on its pharmacokinetic characteristics. ⋯ In this patient population, neither age nor gender influence elimination of rapacuronium. This finding contrasts to an age-related decrease in plasma clearance observed in a study of 10 healthy volunteers and in a pooled analysis of the pharmacokinetic data from 206 adults in multiple clinical studies. Even if ORG9488 has a potency similar to that of rapacuronium, its plasma concentrations after a single bolus dose of rapacuronium are sufficiently small to contribute minimally to neuromuscular blockade.
-
The purpose of this study was to determine current practice patterns for preoperative fasting at major pediatric hospitals. ⋯ There is no uniform fasting practice for children before elective surgery in the United States and Canada. However, there is agreement among most institutions that ingestion of clear fluids 2-3 h prior to general anesthesia is acceptable. Most also accept a 4-h restriction for breast milk and a 6-h restriction for nonhuman formula. There is great diversity among institutions regarding fasting for solids in children, with many restricting intake after midnight. There is little agreement about whether infant formula should be treated in the same way as solid food or how to categorize breast milk.