Sunday, October 9, 2016

Interscalene block anesthesia for Total Shoulder Arthroplasty - is it a good idea?

The Patterns of Utilization of Interscalene Nerve Blocks for Total Shoulder Arthroplasty.

These authors reported the national demographics of patients receiving interscalene nerve blocks (ISB) for total shoulder arthroplasties using data from the National Anesthesia Clinical Outcomes Registry from 2010 to 2015.

They found that of 28,810 cases, 
41 % received an ISB and a general anesthetic 
1% received ISB as the primary anesthetic. 

From 2010 to 2014, they noted an increase in ISB utilization for this surgery (odds ratio, 1.21; 95% confidence interval, 1.19-1.23; P < .0001). 

They found a wide variation in block utilization among the 50 states of the US. 

Comment:The authors cite evidence that ISBs are associated with reduced postoperative opioid consumption, decreased postoperative nausea/vomiting, and expedited recovery room length of stay and hospital discharge. They do not provide information on the incremental cost of administering both a general and a regional anesthetic.

They suggest that possible explanations for a relatively lower percentage of ISB utilization include concerns related to known complications, lack of available anesthesiologists  skilled in this subspecialty, provider preference, or lack of technical resources or appropriate workflows.

Our practice is to avoid the routine use of ISB's in patient having shoulder arthroplasty for reasons expressed in this link. In most cases we are able to transition the patient to oral analgesics on the evening of the procedure, even though we are implementing range of motion exercises immediately after surgery. The advantages of avoiding an ISB include (1) avoiding surgical delays while the block is administered and verified, (2) avoiding patient anxiety about having a needle placed in the neck, (3) avoiding concern regarding the experience of the anesthesiologist with ISBs, (4)  the ability to do a neurological exam right after surgery, (5) avoiding having to manage an increase in pain when a block wears off in the middle of the night, (6) avoiding patient concerns about the inability to move or protect the arm while the block is in effect, and (7) avoiding what can be permanent complications as shown in this link and in this recent post.