Shoulder block safer, more effective than interscalene block for arthroscopic shoulder surgeries

Arthroscopic orthopedic surgery can cause a lot of pain and discomfort after the procedure. Interscalene block (ISB) has been linked to side effects such as phrenic nerve palsy. Shoulder block (ShB) is a relatively new diaphragm-sparing analgesic option in these situations.

A recent study published in the Indian Journal of Anesthesia by the AIIMS team found out that shoulder block can be preferred over interscalene block for arthroscopic surgeries.

This study included a total of 70 adult patients undergoing arthroscopic Bankart repair surgery. Patients were grouped into Group ISB who received 0.5 percent bupivacaine 10 ml and Group ShB who received 0.5 percent bupivacaine (suprascapular block 10 ml and axillary block 10 ml)] using Ultrasound and a nerve stimulator.

Key findings included are:

The results show that arthroscopic Bankart repair using a single shot dual guidance ShB is a safe and successful procedure which produced equivalent analgesic consumption and patient satisfaction as ISB, with less motor block and fewer side effects.

ShB group had partial motor blockade in 100 percent of cases, whereas ISB patients had total motor block in 88.6% of cases because ISB paralyses the entire upper limb.

The posterior rotator cuff muscles and the deltoid were affected by ShB. So, the incidence of postoperative paresthesia and motor impairment was substantially greater in the ISB group.

The initial analgesic need in ISB group was substantially delayed (8.2 h vs. 4.6 h), while in the ShB group 4 h Visual Analogue Source (VAS) was much greater. VAS in ISB group was significantly greater at 12 hours.

In the ISB group, dyspnea was observed in a patient (2.9%) and ptosis was noticed in two patients (5.7%), whereas no problems were detected in the ShB group. The two groups' satisfaction levels at 24 hours were comparable, and none of them reported a low degree of satisfaction.

In conclusion the lead, Dr. Saini said "ShB and ISB have similar efficacy in terms of VAS in recovery, cumulative analgesic requirement, and patient satisfaction. ISB prolonged the time to first analgesic request but resulted in significantly higher delayed rebound pain. Considering the undesirable effects associated with ISB like phrenic nerve blockade, prolonged upper limb weakness and the occurrence of rebound pain, ShB may be preferred for arthroscopic shoulder surgeries."

Source

Saini S, Rao SM, Agrawal N, Gupta A. Comparison of analgesic efficacy of shoulder block versus interscalene block for postoperative analgesia in arthroscopic shoulder surgeries: A randomised trial. Indian J Anaesth 2021;65:451-7