Persistent postsurgical pain is a common problem that adversely affects the quality of life. A study hypothesized that using pregabalin and ketamine would prevent persistent pain after cardiac surgery.

The study enrolled adults without chronic pain and those undergoing elective cardiac surgery via sternotomy. It randomized them to receive either usual care, pregabalin (150 mg preoperatively and twice daily for 14 postoperative days) alone, or along with a 48-h postoperative infusion of intravenous ketamine at 0.1 mg/kg/h. The study observed the prevalence of clinically significant pain at 3 and 6 months after surgery, described as a pain score on the numeric rating scale of >/=4 (out of 10) after a functional assessment of three maximal coughs. It also assessed acute pain, opioid use, safety measures, long-term neuropathic pain, analgesic requirement, and quality of life.

The results were as follows-

• The study enrolled 150 patients.
• The prevalence of pain at three postoperative months was lower for pregabalin alone (6%) and in combination with ketamine (2%) than in the control group (34%).
• The prevalence of pain at six postoperative months was lower for pregabalin alone (6%) and in combination with ketamine (0%) than in the control group(28%). 
•  Both active arms showed more cases of Diplopia.

Thus, Preoperative administration of 150 mg of pregabalin and postoperative continuation twice daily for 14 days can significantly lower the prevalence of persistent pain after cardiac surgery.

Anwar S, Cooper J, Rahman J, Sharma C, Langford R. Prolonged Perioperative Use of Pregabalin and Ketamine to Prevent Persistent Pain after Cardiac Surgery. Anesthesiology July 2019;131:119–131. https://doi.org/10.1097/ALN.0000000000002751