Post-surgical Pain Management Can Influence Progression to Chronic Pain

PITTSBURGH, May 18, 2017 – Surgery is the cause for chronic pain in nearly 1 in 4 individuals who endure persistent pain conditions. Understanding pre-operative and post-op factors that influence post-surgical pain management success may provide clues in preventing progression to chronic pain after surgery, according to research presented at the American Pain Society (APS) Annual Scientific Conference, www.americanpainsociety.org

Timothy Brennan, MD, anesthesiologist and professor at University of Iowa Medical Center, delivered the Global Year Against Pain Lecture at the APS meeting titled “What Can We Learn from Post-operative Pain?” Every year, the International Association for the Study of Pain (IASP) identifies a pain condition for a year-long awareness building campaign, and 2017 is the Global Year Against Pain After Surgery. In its announcement, IASP said: “Millions of patient experience pain after surgery each year and inadequate treatment can prolong post-operative suffering and disability and perhaps lead to chronic pain.” APS supports the IASP campaign.

“Post-operative pain, its consequences and response to treatment, vary greatly among patients,” said Brennan. “Most postoperative pain resolves, however, chronic pain after surgery and continued medication use are increasingly recognized as important perioperative problems.” He added that post-operative pain is a model of not only acute pain, but the development of chronic pain. In general, research shows that reducing pain with various analgesic treatments has been successful for pain management in the acute postoperative period, but there are exceptions.

“Although we assume that good treatment of acute post-surgical pain will prevent chronic pain, higher severity of acute pain during the first three days after surgery is associated with greater likelihood for progression to chronic pain,” said Brennan. He explained that since most surgeries are elective, there usually is time to assess patients prior to surgery to predict the impact of pre-and post-op variables that could influence whose pain resolves and whose doesn’t.

“We know that procedure-specific chronic conditions occur after common operations, such as the severe pain associated with breast and cardiac surgeries and orthopedic joint replacements. However, it has been very difficult to understand the pathogenesis, prevention and treatment of postoperative chronic pain,” said Brennan. “Also, it is well known that psychosocial factors strongly impact transition from acute to chronic pain. Limited coping ability, depression, and anxiety can predict poorer acute pain control and advancement to persistent postsurgical pain.”

Brennan said opioids remain the primary therapeutic strategy for treatment of acute post-op pain, but opioid requirements and pain can vary greatly among patients – even for the same surgery. Minimally invasive procedures typically cause less pain than open surgeries, and a variety of opioid-sparing strategies can be employed, such as peripheral nerve blocks, inter-operative ketamine administration, neuraxial infusion of local anesthetics and oral or intravenous NSAIDS, COX-2 inhibitors and
acetaminophen.

Sometimes treatment success may require high doses of opioids, and Brennan noted that those involved in perioperative care need better understanding about long-term use of opioids after acute post-op pain. “We need to learn more about long-term use of opioids after acute postoperative pain and identify patient subgroups at high risk in order to reduce progression to chronic opioid use.”

Brennan concluded that further studies are needed to help predict which surgical patients are most likely to develop chronic pain and continue
using opioids and other drugs. “In future studies, batteries of psychosocial variables could be assessed before and after surgery in larger numbers of patients. Measures of neuropathic pain, mood and function can be added to assess the impact of these factors on pain outcomes.”

About the American Pain Society

Based in Chicago, the American Pain Society (APS) is a multidisciplinary community that brings together a diverse group of scientists, clinicians and other professionals to
increase the knowledge of pain and transform public policy and clinical practice to reduce pain-related suffering. APS is the professional home for investigators
involved in all aspects of pain research including basic, translational, clinical and health services research to obtain the support and inspiration they need to flourish professionally. APS strongly advocates expansion of high quality pain research to help advance science to achieve effective and responsible pain relief. For more information on APS, visit www.americanpainsociety.org.