Cannabis Users Had Triple the Hematoma Risk After Breast Reconstruction Surgery

Cannabis users (12.1% of the cohort) had significantly higher rates of postoperative hematoma (OR 3.078 for general hematoma, OR 3.098 for breast hematoma) and readmission (OR 2.865) after DIEP flap breast reconstruction. Cannabis users were also younger and had higher BMI. A 5-fold increase in the proportion of cannabis users was observed from 2015 to 2023.

Retrospective study of 719 adult patients (87 cannabis users, 632 non-users) who underwent DIEP flap autologous breast reconstruction between January 2015 and December 2023 by five plastic surgeons at a single institution. Multivariable logistic regression controlled for confounders.

As cannabis use becomes more common among surgical patients, understanding its effects on surgical outcomes is critical for preoperative risk assessment. The 5-fold increase in cannabis-using patients over the study period underscores the growing relevance of this issue.

Cannabis affects platelet function and vascular tone, which may explain the increased bleeding risk observed. As more plastic surgery patients disclose cannabis use, surgeons may need to incorporate cannabis history into preoperative risk discussions and potentially modify perioperative management.

Single institution, retrospective design. Cannabis use was self-reported and may be underestimated. Could not assess dose, frequency, or timing of last use relative to surgery. Cannabis users differed from non-users in age and BMI, and residual confounding is possible.