Preoperative cannabis use had no effect on pain or outcomes after cardiac surgery

Average morphine equivalents in the first 48 hours: cannabis users 60.98 vs non-users 59.90 (p=0.93). VAS pain at 24 hours: 5.52 vs 4.84 (p=0.414). VAS at 48 hours: 4.74 vs 3.90 (p=0.23). Time to extubation was nearly identical (718.41 vs 718.67 minutes, p=0.99). No differences in ICU length of stay, nausea/vomiting, reoperation, or in-hospital mortality.

Single-center prospective study of adults undergoing cardiac surgery via sternotomy. Patients were surveyed about cannabis use during preoperative consultation. 50 non-users and 23 cannabis users were compared. Primary outcomes: morphine equivalents in first 48 hours and VAS pain scores. Secondary outcomes: extubation time, nausea, ICU stay, reoperation, mortality.

There has been concern that cannabis users might require more opioids postoperatively due to cross-tolerance, or that cannabis might affect surgical outcomes. This study provides reassuring data that preoperative cannabis use did not worsen any measured outcome after cardiac surgery.

As cannabis use becomes more prevalent, surgeons and anesthesiologists need data on how it affects perioperative outcomes. The null findings across every measured outcome are reassuring and suggest that cannabis use alone should not alter surgical planning for cardiac procedures, though the small sample size warrants confirmation.

Small sample, especially the cannabis group (n=23), limiting power to detect moderate effects. Single center. Cannabis use was self-reported and not verified biochemically. No information on dose, frequency, or recency of cannabis use. The study may be underpowered for rare outcomes like reoperation or mortality.