Diaphragm Sparing Effect of Subomohyoid Block With Infraclavicular or Subscapularis Blocks in Comparison With Interscalen Block for Postoperative Analgesia in Shoulder Surgeries

Overview

The gold standard for shoulder analgesia is the interscalene block (ISB), but it has its own share of disadvantages such as phrenic nerve block, recurrent laryngeal nerve involvement and Horner's syndrome may lead to patient discomfort .Others, such as intrathecal spread and systemic toxicity of local anesthetic, can have serious consequences. Phrenic nerve injury is a common complication with regional anesthesia. Its either temporary with Transient Phrenic Nerve Palsy leading to hemidiaphragmatic paresis after interscalene block or other injections of local anesthetic in the neck . Although studies of ISB have shown a reduction in the incidence in hemidiaphragmatic paralysis with low-volume ISB, the risk of phrenic paralysis is not completely eliminated. To bypass this complication, distal block of the shoulder innervation is recommended such as subomohyoid infraclavicular and subomohyoid subscapularis blocks.

Ultrasound has a significant role in recent anesthesia. It plays a significant role in detecting diaphragmatic mobility and detecting phrenic nerve palsy after regional anesthesia . the common and standard technique for shoulder analgesia is interscalen block. but it has its own complications like phrenic nerve palsy. to bypass this complications ,several ways had been tried to overcome this complications. in this study, the investigator compare between the standard interscalen block with distal blocks like infraclavicular subomohyoid block and subomohyoid subscapularis blocks according to diaghragm affection , duration of analgesia , side effects occured with blocks. For infraclavicular subomohyoid block, the infraclavicular approach targets the posterior and lateral cords, thus anesthetizing the axillary nerve (which supplies the anterior and posterior shoulder joint), whereas the suprascapular nerve block done by blocking subomohyoid muscle anesthetizes the posterior shoulder. For subscapularis subomohyoid block, subscapularis is done before subomohyoid block. Subscapularis block target subscapular nerve which arise from posterior cord and present on ventral surface of subscapularis muscle .