Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

STUDY SIGNIFICANCE Significant numbers of patients undergoing major surgeries develop chronic postsurgical pain (CPSP) every year. CPSP can be so severe, stressful, and intractable that it can require extensive medical care long after the initial surgery. Since stress intensifies pain, many nonpharmacological pain interventions involve eliciting one's relaxation response to "turn down" pain signals. However, pre-existing difficulties in eliciting one's relaxation response to cope with pain-related stress may be a risk factor for developing CPSP. Previous research has shown that breath-focused mindfulness meditation is effective for reducing pain symptoms and eliciting relaxation. Using an innovative, hospital-integrated assessment protocol, my proposed dissertation research will test the relaxation response as a risk factor for developing CPSP. STUDY METHODS The relaxation response is primarily activated by the vagus nerve, a major parasympathetic nerve involved in decreasing heart rate and pain signals. Patients undergoing thoracic surgery at the Toronto General Hospital will be assessed for vagus nerve activity using non-invasive heart rate variability measures during rest, pain-induction, and mindful breathing. The assessments will take place ~1 week before and 3 months after surgery on a total of 60 patients; n = 30 with CPSP, and n = 30 without CPSP. We will test whether vagus nerve activity predicts the onset of CPSP 3 months after surgery, and also examine differences in vagus nerve activity between patients with and without CPSP. IMPACT ON PATIENTS & HEALTHCARE Thousands of Canadians undergo surgery yearly to treat major illnesses and ~10% will develop moderate-to-severe chronic postsurgical pain. Results from this study will promote future research on how relaxation response data can be used to predict CPSP, and inform preventive treatment strategies for CPSP and other pain conditions to be implemented into perioperative and outpatient care settings.