Published: 07/27/2026 | Author: Quentin Blount

A large Canadian clinical trial has found that targeted nerve blocks can significantly cut opioid use after cardiac surgery. The team notes that this can reshape how these potentially addictive drugs are used following one of the most opioid-intensive procedures in medicine. 

For anyone concerned about opioid addiction risk following surgery, the results point to a concrete way hospitals can reduce unnecessary exposure to opioids from the very start.

The Opioid Crisis in Context

Cardiac surgery has historically lagged behind other surgical fields in adopting opioid-sparing pain control. Anesthetic gases used to keep patients unconscious during heart surgery can significantly lower blood pressure, so care teams often lean more heavily on opioids to keep blood pressure and heart rate stable during the operation. That reliance carries forward into recovery, where patients frequently receive high doses of opioids for post-surgical pain, even though some studies have shown that opioids don’t reduce long-term pain.

Clinicians are well aware of the addictive nature of opioid use after an operation. Some new surgery procedures have omitted opioids altogether. However, these new approaches remain in the experimental stage.

The EPOCH-CardioLink-10 trial, led by researchers at St. Michael’s Hospital in Toronto and conducted across hospitals in four Canadian provinces, enrolled 318 adults undergoing cardiac surgery involving a median sternotomy, the standard procedure that involves splitting the breastbone. The team randomly assigned participants to receive continuous nerve blocks delivering either the local anesthetic ropivacaine or a placebo for two days after surgery.

Nerve Blocks Have a Role

Researchers adapted a nerve block technique from pediatric medicine, using a superficial parasternal intercostal plane block to numb the intercostal nerves near the sternum that transmit pain from the chest area. Within the first 72 hours after surgery, patients who received the ropivacaine nerve block used an average of 20.7 fewer morphine milligram equivalents compared to those who received the placebo. 

They were also nearly half as likely to require very high opioid doses, with 12.9% reaching at least 200 morphine milligram equivalents compared to 23% in the placebo group.

Narcotics and How to Treat Them

Opioids work by binding to receptors in the brain and body that control pain and reward, which is why they’re effective painkillers but also carry a high risk of dependence with repeated use. Every opioid prescription, including those given after surgery, carries risk of developing into longer-term use, particularly for patients with prior substance use history. 

Reducing the total opioid dose a patient receives after a major surgery like this is one of the most direct ways to lower that risk from the outset.

This trial matters for harm reduction because they attack the problem upstream, before a prescription morphs into a dependency. For people who develop opioid use disorder, whether from a surgical prescription or otherwise, medication-assisted treatment using buprenorphine, methadone, or naltrexone remains one of the most effective evidence-based paths to recovery. 

Naloxone should also be available to anyone using or recovering from opioid use, since it can reverse an overdose in an emergency.

Peer support through Narcotics Anonymous meetings can complement medical treatment for people navigating opioid use disorder, whether their path into dependence started with a prescription or otherwise.

Enter NA

Patients preparing for major surgery can ask their care team whether nerve blocks or other opioid-sparing techniques are available to reduce their opioid exposure from the start. 

For those already managing opioid use disorder, NA meetings and opioid treatment programs remain available locally. You can also find harm reduction resources such as naloxone distribution and fentanyl test strips. 

Getting started with NA can prevent a dependency before it gets out of control. Just call 800-934-1582(Sponsored) to chat with an expert about opioid addiction treatment options. You can also search our directory to locate NA meetings anywhere in the country.