Articles: nerve-block.
-
Anesthesia and analgesia · Apr 1992
Enhancement of bupivacaine sensory blockade of rat sciatic nerve by combination with phenol.
We sought to determine whether the addition of phenol would enhance a bupivacaine nerve block. The effects on nerve conduction of bupivacaine (0.125%) and phenol (0.5%), singly and combined, were evaluated in vivo on the rat sciatic nerve. Three groups of 10 animals each were used. ⋯ The analgesia score derived from the hot-plate test was more and persisted longer for the combination treatment than for either 0.125% bupivacaine or 0.5% phenol given singly; e.g., the average sensory block score after 150 min for the combination treatment was 1.0 compared with 0.1 for either bupivacaine or phenol given alone (P = 0.003). Analysis of the areas under the sensory score-time curves also demonstrated enhanced blockade from the combination treatment, which would be consistent with a synergism of the separate Na(+)-channel blocking effects of charged and uncharged local anesthetics. These findings may suggest other candidates for clinically useful combinations of amine and neutral local anesthetics.
-
J Pharmacol Toxicol Methods · Apr 1992
A sciatic nerve blockade method to differentiate drug-induced local anesthesia from neuromuscular blockade in mice.
This report introduces a simple and easy technique for animal handling and drug administration into the sciatic nerve area for determining local anesthesia and neuromuscular blocking activity in mice. The drugs were injected into the popliteal space of the right hindlimb (i.e., the sciatic nerve area). The loss of motor activity of the right hindlimb was taken as a sign of producing local anesthesia. ⋯ The method reported here has been validated by reference neuromuscular blocking agents (d-tubocurarine, decamethonium, and succinylcholine). A positive neuromuscular blockade was recorded when a mouse was unable to stay on the inverted wire mesh screen. The information provides not only the local anesthetic or neuromuscular blocking potency of drugs but also duration of action of drugs.
-
Journal de chirurgie · Apr 1992
Case Reports[Pneumatic tourniquet paralysis. A differential diagnosis after loco-regional anesthesia of the upper limb].
A case is reported of a severe neurological deficit after hand surgical using pneumatic tourniquet. The 51 year old ASA I patient underwent an axillary block for hand surgery using 50 ml of mepivacaïne 1%. The tourniquet was remained at 300 mmHg for only 45 min. ⋯ As there was no improvement, epineurotomy was carried out on day 60, to liberate the median nerve which was severely compressed in the canal brachial. The patient then started to improve slowly. But many safety factors can decrease the rate complications: the accuracy and integrity of the pressure-monitoring must be verified, a tourniquet pressure above 300-500 mmHg would rarely be required in normotensive patient with compliant vessel, a pressure of 200 mmHg will almost all cases provide a bloodless field, tourniquet must be applied on diaphysis and not on bony relief.
-
A new technique for regional anaesthesia for arthroscopy of the knee is presented. The method includes sciatic nerve block according to the technique proposed by Labat, through a posterior approach and the block of the femoral and lateral cutaneous nerves using a single anterior approach. Results obtained in 30 patients are presented: they include good stability of the cardiovascular and respiratory parameters, high efficiency and duration of anaesthesia resulting in a satisfactory surgical procedure.