Regional Anesthesia for Arthroscopic Shoulder Surgery: Comparison between Ultrasound Guided Interscalene Brachial Plexus Block and Combined Suprascapular Nerve and Supraclavicular Nerve Block

Abstract

Anesthesia options for upper extremity surgery include general and regional anesthesia. Brachial plexus blockade has severaladvantages including decreased hemodynamic instability, avoidance of airway instrumentation, and intra, as well as postoperativeanalgesia. Prior to the availability of ultrasound the risks of complications and failure of regional anesthesia made generalanesthesia a more desirable option for anesthesiologists inexperienced in the practice of regional anesthesia. Ultrasonography hasrevolutionized the practice of regional anesthesia. By visualizing needle entry throughout the procedure, the relationship betweenthe anatomical structures and the needle can reduce the incidence of complications. In addition, direct visualization of the spreadof local anesthesia around the nerves provides instant feedback regarding the likely success of the block. The interscalene approach to the brachial plexus is the technique of choice for surgical procedures of the shoulder. However, interscalene blockade is associated with numerous possible complications, such as ipsilateral phrenic nerve paralysis, injury to the brachial plexus, paralysis of vagus, recurrent laryngeal, and the cervical sympathetic nerve, inadvertent epidural and spinal anesthesia, pneumothorax and respiratory distress. The riskfor most of these complications is minimized by awarenessof the location of the needle and surrounding structures, facilitated with ultrasound guidance. Recent studies have suggested that, the combination of ultrasound-guided supraclavicular and suprascapular block may offer more suitable and safe conditions for shoulder arthroscopy than that offered by ultrasound-guided interscalene block. However, theconcern with using supraclavicular block for shoulder surgery is that proximal nerves and nerve branches that supply the shoulder may be missed. Moreover, the suprascapular nerveblock has the basic risks of any peripheral nerve block:nerve injury, intravascular injection, and vascular puncture, in addition to the risk ofpneumothorax. Blindand image-guided techniques have been described for suprascapular nerve block, all of which target thenerve within the supraspinous fossa or at the suprascapular notch. Thisclassic target point is not always ideal when ultrasound is usedbecause it is located deep under the muscles, and hence the nerve is notalways visible. In our study sixty patients scheduled for arthroscopic shoulder surgery were assessed preoperatively for evaluation of their medical status and their laboratory investigations. Patients were divided into 2 groups, the first group received ultrasound guided interscalene brachial plexus nerve block while the second group received ultrasound guided combined suprascapular and supraclavicular nerve blocks. The assessment of both groups was performed intraoperatively, as regards onset and duration of sensory and motor blocks, the degree of motor block, the incidence of respiratory compromise, the need for use of intraoperative analgesia as regards total volume and frequency of supplementation and hemodynamics of the patients as heart rate, respiratory rate, mean arterial blood pressure and oxygen saturation. Postoperative patient assessment included pain severity measurement using the visual analogue scale, the requirement of postoperative analgesics and the time to first request of analgesia through the first 24 hours after surgery. Moreover, surgeon and patient satisfaction was also assessed. The study revealed that ultrasound guided interscalene brachial plexus block compared to combined ultrasound guided suprascapular and supraclavicular nerve blocks in shoulder arthroscopy, provided less dose and frequency of administration of rescue analgesia, superior surgeon and patient satisfaction and better postoperative pain control. Moreover, both techniques showedsimilar outcomes as regards respiratory compromise and hemodynamic stability in terms of blood pressure and heart rate. Previous studies came to an agreement to the result of our current study that ultrasound guided interscalene brachial plexus block ascertained more pain relief and less use of postoperative analgesics than combined ultrasound guided suprascapular and supraclavicular nerve block.