Shoulder Surgery Pain Relief Method May Not Be That Effective

What is currently considered to be the “gold standard” for post-shoulder surgery pain management may not be as effective as what once was believed.

An interscalene block (ISB) can help keep pain at bay after shoulder surgery and patients are often given a single shot of freezing, like lidocaine or ropivacaine, along with oral painkillers for relief. This method was believed to keep patients comfortable 24 to 48 hours after the procedure. However, Faraj Abdallah, MD, an anesthesiologist at St. Michael’s Hospital in Toronto, ON, and his colleagues found results that challenge the effectiveness of ISB.

The team reviewed 23 randomized controlled studies, including 1,090 patients, of shoulder surgeries performed between 1970 and 2014. They compared the severity of pain recorded at rest 24 hours after surgery from patients who received ISB and those who did not. Pain was rated on a scale from 0, being none, to 10, being the worst.

The study, published in Anesthesia & Analgesia, revealed that:

• The single shot provided pain relief for 6 to 8 hours after surgery
• Patients experienced similar pain between 8 and 16 hours after surgery regardless if they had the ISB or not
• Those who received the ISB had slightly more, not less, pain between 16 and 24 hours after surgery — attributed as rebound pain

Going more in depth about the rebound pain, Abdallah explained that one reason for it can be because patients may under-medicate with the painkillers since they had the ISB.

Although the authors concluded that there was no indication of pain relief from the ISB after the 6 to 8 hour mark, the shot did provide other benefits. The results showed a reduction in opioid consumption for up to 12 hours following the surgery and a decrease in nausea and vomiting 24 hours afterwards. In addition the ISB accelerated hospital discharge.

Despite the positives, pain management is still a concern regarding the freezing shot.

“The practical impact of this study is that strategies to prolong the duration of nerve blocks, especially on shoulder surgery, need to be incorporated in our practice,” Abdallah said in a news release.