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Psychological interventions can help reduce risk of persistent pain after surgery but timing is critical, a pain expert said at the virtual 2021 American Academy of Pain Medicine annual meeting.

"We can look at chronic pain as occurring in a very linear process," said Ravi Prasad, PhD, of University of California Davis, in a about multimodal ways to prevent chronic post-surgical pain.

"By definition, pain starts off as something acute," Prasad noted. The acute phase includes assessments and treatment to try to eliminate pain quickly.

"When the pain condition fails to respond to some of these initial treatments, it starts to enter the subacute category," Prasad said. "The patient is still engaged in different medical workups to try to identify the cause of the pain and still participating in treatments, but they haven't responded to the interventions in the manner expected, meaning the pain continues to persist." This is usually about 3 to 6 months after the acute phase.

When a patient's pain reports have plateaued and pain is refractory to medical treatments for at least 6 months, it can become chronic.

"It's important to recognize these time points exist," Prasad emphasized. "We can intervene at these different points -- and intervene even prior to the experience of acute pain -- to try to minimize the likelihood that persistent pain develops."

Factors that contribute to chronic pain include environmental stressors, lifestyle factors, unhealthy support systems, limited access to care, and patient risk factors including history of substance abuse, adverse childhood experiences, and psychiatric conditions.

Research has shown the most useful after surgery were pre-surgical somatization, depression, anxiety, and poor coping.

"All of these are things that are actually modifiable," Prasad said. "We can actually do something about these to change the outcomes a person might have."

Cognitive therapies and relaxation training are two interventions receiving a lot of attention, he noted. Breathing, relaxation exercises, and meditative practices can help patients learn to quiet the nervous system by working on the sympathetic-parasympathetic axis. But cognitive processes also have to be targeted, Prasad observed, and "this is where cognitive behavioral therapy can come in."

The crux of cognitive behavioral theory is that "by changing the interpretation, we can change the impact of consequences at the emotional, physical, and behavioral level," Prasad said. "The challenge with this is that our interpretations tend to be automatic."

"Making changes in our interpretation is difficult because we have to become aware of processes that are occurring in our subconscious and make changes in something that's been with us for a very long period of time," he acknowledged. "These thought processes can be very resistant to change. But it's essential we do this if we want to have sustained change in our outcomes."

It's not something as simple as turning negative thoughts into positive ones, Prasad added. "Rather, we look at the accuracy and the degree of helpfulness of the thoughts, and modify the thoughts into something that is more accurate and helpful."

"We know that when people engage in cognitive behavioral therapy, their outcomes are improved. Affective stress is decreased, pain sensitivity decreases, and this can minimize opioid burden," he continued. And it's not the only intervention that can help: "there's a wide range of psychological-based tools that have a strong evidence base behind them," including biofeedback training and mindfulness-based stress reduction.

But timing of these treatments is essential, Prasad emphasized.

"The way to optimize timing is to do presurgical screening to identify what's the most appropriate intervention for the patient," he said. Some patients may need help before surgery, others can be targeted at the acute or subacute phase. "Regardless, we want to make sure we address symptoms as early as possible and not wait for pain to be in a chronic state."

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