Comparison of Analgesic Outcomes Following Sciatic Nerve Blockade Performed by Resident Trainees and Nurse Anesthetists

Background and objectives: Peripheral nerve blockade requires regional anesthesia skills that are taught in several formats and assessing technical proficiency has shifted from fulfillment of quotas to comprehensive procedural evaluation. Complete analgesia is the clinical endpoint validating successful nerve blockade but patient, technical and procedural factors influence this result. The purpose of this study was to determine if physician trainee or nurse anesthetist administered sciatic nerve blockade influence postoperative pain scores and opioid analgesic requirements and if patient factors, technique and repetition influence this outcome. Method: Sciatic nerve blockade by nerve stimulation and ultrasound based techniques were performed by senior anesthesiology resident trainees and nurse anesthetists under the supervision of regional anesthesia faculty. Preoperative patient characteristics including obesity, trauma, chronic pain, opioid use and preoperative pain scores were recorded and compared to the post-procedure pain scores and opioid analgesic requirements upon discharge from the post-anesthesia care unit and 24 hours following sciatic nerve blockade. Results: 93 patients received sciatic nerve blockade from 22 nurse anesthetists and 21 residents during 36 months. A significant relation between training background and improved pain scores was not demonstrated but transition from nerve stimulation to ultrasound guided techniques lowered immediate opioid usage in all groups. Patients with pre-existing chronic opioid use had higher postoperative pain scores and opioid dosages following nerve block. Conclusion: Patient analgesia should be an integral measure of proficiency in regional anesthesia techniques and evaluating this procedure outcome for all practitioners throughout their training and beyond graduation will longitudinally assess technical expertise.

Postoperative Analgesia Following Sciatic Nerve Blockade Administered by Nurse Anesthetists Supervised by Regional Anesthesia Faculty in an Academic Hospital

Introduction: Assessment of expertise in regional anesthesia techniques is traditionally based upon quota fulfillment of procedures during training. Validation of practitioner proficiency in performing procedures in surgical specialties has moved from simple measurement of technical skills to evaluation of global patient outcomes. Complete absence of pain as a result of nerve blockade is the most important clinical endpoint but patient, technical and procedural factors influence results. The purpose of this study was to measure the postoperative pain scores and associated analgesic medication requirements for patients administered sciatic nerve blockade by nurse anesthetists and determine patient or procedural factors that influenced this outcome. Methods: Either nerve stimulator or ultrasound guided sciatic nerve blockade was administered by nurse anesthetists under the supervision of regional anesthesia faculty. Patient demographic data that was collected included gender, body mass index, surgical procedure, and pre-existing chronic pain with associated opioid use. Patient self-reported pain scores and opioid analgesic dosages in the preoperative, intraoperative, immediate postoperative and 24 hour post procedure intervals were recorded. Results: 22 nurse anesthetists administered sciatic nerve blockade to 48 patients during a 36 month interval. Transition from a nerve stimulator to ultrasound guided sciatic nerve block technique resulted in lower mean pain scores. Patients reporting chronic opioid use were observed to have elevated perioperative opioid analgesic requirements and pain scores compared to opioid naïve patients. Conclusion: Effective analgesia is a prime measure for assessing expertise in regional anesthesia and continuous evaluation of this outcome in everyday practice is proposed.

Abstract Title: Ultrasound Guided Trans-sartorial Continuous Saphenous Nerve Blockade - A technique for Relief of Postoperative Medial Incisional Foot and Ankle Pain

The saphenous nerve (SaN) innervates the region from the upper medial thigh to the medial aspect of the foot and ankle. A femoral nerve block (FNB) is effective for blockade of the SaN but this causes quadriceps weekness and reduced patient mobility that is unsuitable in an ambulatory surgical setting.

Regional Anesthesia in TraumaMedicine

Regional anesthesia is an established method to provide analgesia for patients in the operating room and during the postoperative phase. While regional anesthesia offers unique advantages, as shown by the recent military experience, it is not commonly utilized in the prehospital or emergency department setting. Most often, regional anesthesia techniques for traumatized patients are first utilized in the operating room for procedural anesthesia or for postoperative pain control. While infiltration or single nerve block procedures are often used by surgeons or emergency medicine physicians in the preoperative phase, more advanced techniques such as plexus block procedures or regional catheter placements are more commonly performed by anesthesiologists for surgery or postoperative pain control. These regional techniques offer advantages over intravenous anesthesia, not just in the perioperative phase but also in the acute phase of traumatized patients and during the initial transport of injured patients. Anesthesiologists have extensive experience with regional techniques and are able to introduce regional anesthesia into settings outside the operating room and in the early treatment phases of trauma patients.

Patient Variability in Sciatic Nerve Branch Point Distance Using Ultrasound Guided Localization

Background and Objectives: Improved ultrasound and needle technology make popliteal sciatic nerve blockade a popular anesthetic technique and imaging to localize the branch point of the common peroneal and posterior tibial components is important because successful blockade techniques vary with respect to injection of the common trunk proximally or separate injections distally. Nerve stimulation, ultrasound, cadaveric and magnetic resonance studies demonstrate variability in distance and discordance between imaging and anatomic examination of the branch point. The popliteal crease and imprecise, inaccessible landmarks render measurement of the branch point variable and inaccurate. The purpose of this study was to use the tibial tuberosity, a fixed bony reference, to measure the distance of the branch point. Method: During popliteal sciatic nerve blockade in the supine position the branch point was identified by ultrasound and the block needle was inserted. The vertical distance from the tibial tuberosity prominence and needle insertion point was measured. Results: In 92 patients the branch point is a mean distance of 12.91 cm proximal to the tibial tuberosity and more proximal in male (13.74 cm) than female patients (12.08 cm). Body height is related to the branch point distance and is more proximal in taller patients. Separation into two nerve branches during local anesthetic injection supports notions of more proximal neural anatomic division. Limitations: Imaging of the sciatic nerve division may not equal its true anatomic separation. Conclusion: Refinements in identification and resolution of the anatomic division of the nerve branch point will determine if more accurate localization is of any clinical significance for successful nerve blockade.

Inferior Hypogastric Plexus Block Affects Sacral Nerves and the Superior Hypogastric Plexus

Background. The inferior hypogastric plexus mediates pain sensation through the sympathetic chain for the lower abdominal and pelvic viscera and is thought to be a major structure involved in numerous pelvic and perineal pain syndromes and conditions. Objectives. The objective of this study was to demonstrate the structures affected by an inferior hypogastric plexus blockade utilizing the transsacral approach. Study Design. This is an observational study of fresh cadaver subjects. Setting. The cadaver injections and dissections were performed at the Department of Forensic Sciences and Insurance Medicine, Semmelweis University, Budapest, Hungary after obtaining institutional review board approval. Methods. 5 fresh cadavers underwent inferior hypogastric plexus blockade with radiographic contrast and methylene blue dye injection by the transsacral fluoroscopic technique described by Schultz followed by dissection of the pelvic and perineal structures to localize distribution of the indicator dye. Radiographs demonstrating correct needle localization by contrast spread in the specific tissue plane and photographs of the dye distribution after cadaver dissection were recorded for each subject. Results. In all cadavers the dye spread to the posterior surface of the rectum and the superior hypogastric plexus. The dye also demonstrated distribution to the anterior sacral nerve roots of S1, 2, and 3 with bilateral spread in 3 cadavers and ipsilateral spread in 2 of them. Limitations. The small number of cadaver specimens in this study limits the results and generalization of their clinical significance. Conclusions. Inferior hypogastric plexus blockade by a transsacral approach results in distribution of dye to the anterior sacral nerve roots and superior hypogastric plexus as demonstrated by dye spread in freshly dissected cadavers and not by local anesthetic spread to other pelvic and perineal viscera.