Study of Usg Guided Popliteal Nerve Block for Ankle and Foot Surgeries

Background: Popliteal Nerve Block, a form of regional anaesthesia is given for a variety of foot & ankle surgeries. It is a popular technique to decrease postoperative pain, decrease narcotic use & increase patient satisfaction. Popliteal blocks can be utilized as the sole source of anaesthesia for foot & ankle surgeries. This technique is beneficial in medically compromised patients. Profound analgesia during both the operative & post-operative time periods & avoidance of systemic complications like nausea & vomiting are also potential benefits of popliteal nerve block. Use of ultrasound allows real time visualisation of deposition of local anaesthetic and so can improve the chance of successful nerve blockade. Ultrasound also allowed dose reduction of the local anaesthetic. It reduces the number of needle passes and shortens the block onset time. Methods: All the patients enrolled for USG guided Popliteal Nerve Block will undergo a thorough pre-anaesthetic check-up. Local parts will be examined and written informed consent will be taken from all patients. AS will be explained in detail on the night before the surgery. Patient will be advised to keep Nil per orally for at least 6 hours pre operatively. A peripheral line will be secured for all the patients. Monitors will be applied for -ECG, NIBP, SpO2. Ultrasound machine and its probe will be properly cleaned and aseptically prepared After preparing the parts with povidone iodine, spirit and normal saline solutions, proper draping will be done and a high frequency (5-12 Hz) linear ultrasound probe will be placed transversely at the mid-popliteal crease. After localizing the popliteal artery, probe will be moved proximally to locate the sciatic nerve at or prior to its bifurcation into the tibial and common peroneal branches, the patient will be informed and then a 23G spinal (Quincke) needle will be inserted in-line with and parallel to the transducer from the lateral side of the fossa by using In-plane approach, the whole shaft will be visualized as it progresses towards the nerve. Once placement is confirmed, injection Lignocaine 1.5% 10 ml and injection Bupivacaine 0.5% 5 ml will be injected circumferentially around the sciatic nerve after negative aspiration for blood. 1. Patient will be turned into a supine position. Sensory block will be assessed by pin prick sensation (using the Hollmen scale) and motor block will be assessed by movement of fingers and the ankle joint (using the Hollmen scale). Results: No side effects or adverse reactions were observed whatsoever. All the patients graded the experience as being very satisfied with the anaesthetic technique. Conclusion: Ultrasound-guided popliteal fossa nerve block is an effective and successful technique to provide perioperative sensory and motor blockade for patients undergoing various foot and ankle surgeries. Complications associated with spinals epidural and general anaesthesia can be avoided. Combinations of Lignocaine and Bupivacaine as a local anaesthetic provide faster onset with virtue of good postoperative analgesia.