View clinical trials related to Peripheral Nerve Block.
Filter by:Although the superiority of ultrasound guidance over neurostimulation (NS) has been demonstrated, it has its limits, namely when used for a deeper block (device limits) or if used by a less experienced operator (ability to recognize structures, to correctly position the needle). In addition, its use has failed to consistently prevent intra-neural injection. The question of the usefulness of NS in addition to ultrasound is therefore still relevant. A great geographical disparity exists in the habits of nerve localization. The reluctance to use NS stems mainly from doubts about its effectiveness. The threshold used to consider that the needle is sufficiently close to the nerve and the one used to exclude an intraneural injection have been disputed in several studies. Another weakness of studies concerning NS since the advent of ultrasound guidance is the impossibility of generalizing the results. All clinical studies were performed in an academic setting, and a large majority of them specify that the blocks were performed by - or supervised by - regional anesthesia experts. The only study that attempted to determine the sensitivity of NS used ultrasound as a gold standard. The choice of the ultrasound position as the gold standard is debatable, since it is dependent of the operator. The clinical success of nerve blocks would be a better standard. No study to date has made it possible to calculate the specificity and sensitivity of NS in addition to ultrasound guidance, and therefore, to obtain the positive and negative predictive values of the technique. Obtaining these values could allow each clinical setting or individual to determine the contribution of NS to their rate of success, as a modest increase in the success rate or a minimal decrease in the risk of neuropathy would be clinically significant. The hypothesis is that the sensitivity and specificity of NS justifies its use in combination with ultrasound guidance in most settings, but that the gain in efficiency varies depending on the context (for example depending on the local success rate). To determine the required sample size to test this hypothesis and plan for a definitive study on the question, the investigators need to know what is the local failure rate (incidence of studied event) and what could be the possible rate of patient enrollment. This preliminary, feasibility study will aim to confirm that the local failure rate is compatible with the 5% rate observed in the literature.
The purpose of this research study is to evaluate the analgesic efficacy of adding a single shot parasacral (sciatic) nerve block to a continuous lumbar plexus block in patients undergoing total hip replacement.