View clinical trials related to Sciatic Nerve Block.
Filter by:Little is known about which posture of lower extremity makes it easier to access to the sciatic nerve. In this study, the investigators aimed to identify the most appropriate positioning of the lower extremity during anterior-approach ultrasound-guided sciatic nerve block.
Following painful surgical procedures, postoperative analgesia is often provided with a single-injection peripheral nerve block. Hothe investigatorsver, even with the longest-acting FDA-approved local anesthetic currently available-bupivacaine-the block duration is measured in hours, while the surgical pain may persist for days. A continuous peripheral nerve block allows a prolonged block, consisting of a percutaneously-inserted catheter with its orifice adjacent to a target nerve/plexus through which local anesthetic may be administered. Two basic perineural catheter designs currently exist: (1) catheters that are inserted either through or over a straight hollow-bore needle; and, (2) catheters that are attached to the back of a hollow suture-shaped needle that pulls the catheter adjacent to the target nerve ("suture-method" design). To date, a comparison of the relative risks and benefits of these two designs have not been investigated. The investigators therefore propose a randomized, observer-masked, controlled, parallel-arm, clinical trial to compare these two catheter designs when used to provide post-surgical analgesia following foot and ankle surgery.
56 ASA physical status II and III patients, aged 45-75 year, undergoing elective below knee amputation were randomly assigned to receive either sciatic nerve block using a popliteal approach or a sub gluteal approach. Patients in both groups received same amount of LA and additional ultrasound guided femoral nerve block to ensure sensory block of the medial side of the leg. Success of the block was considered when the block is solid and doesn't require shifting to GA
Clonidine as an adjuvant to local anaesthetics prolongs the postoperative analgesia. It is predominantly an alpha 2 agonist, but does have some alpha 1 activity. Clonidine alone produces analgesia. When administered centrally its effects are predominantly due to its alpha 2 activity. When administered peripherally it prolongs the analgesia through its vasoconstrictor effects and by reducing the clearance of local anaesthetic. Another possibility is that it prolongs analgesia of peripheral nerve blocks due to a hyperpolarisation current .Clonidine has been used successfully both for upper and lower limb blocks. Studies of clonidine for lower limb blocks have produced equivocal results . A major concern with the lower limb blocks is the risk of falls associated with prolonged motor blockade during early mobilisation. Clonidine has been shown to intensify and prolong the motor blockade produced by long acting local anaesthetics. Lidocaine when used in combination with clonidine can increase the duration of analgesia to 8-18 hrs. Greater doses of clonidine are associated with longer analgesia but with more side effects. Clonidine in a dose of 90 mcg administered with local anaesthetics can produce analgesia for up to 10 hrs with minimal side effects. The aim of this study is to compare lidocaine 2% + clonidine 1.5mcg/kg with bupivacaine alone in terms of block selectivity for combined sciatic -saphenous nerve block in patients under going semi elective foot/ankle procedures.
Following foot and ankle surgery, ultrasound-guided sciatic nerve block (SNB) at the popliteal fossa decreases post-operative pain and opioid consumption. At the popliteal fossa, the sciatic nerve bifurcates to form the Common Peroneal Nerve (CPN) and Tibial Nerve (TN). Studies have shown that when both branches are blocked separately distal to the bifurcation site, block onset time is reduced by 30%. Through clinical observation, the investigators found that onset time is further shortened when ultrasound-guided SNB is performed at the site of bifurcation. This is because the local anesthetic spreads interneurally. The purpose of this study is to compare the block onset time of an ultrasound-guided sciatic nerve block at the site of nerve bifurcation with the blockade of each terminal nerve separately (TN and CPN) distal to sciatic nerve bifurcation.