Impact of cannabis on outcome in patients following traumatic injury.

Introduction: Outcomes of trauma patients who tested positive for cannabis at the time of admission showed variable results. Sample size and research methodology that was used in prior studies may have resulted in the conflict. The purpose of the study was to evaluate the impact of cannabis use on outcomes in trauma patients using national data. Our hypothesis was that the use of cannabis will impact outcomes.

Methods: The trauma quality improvement program (TQIP) Participant Use File (PUF) database of the calendar years 2017 and 2018 were accessed for the study. All trauma patients aged 12 years old and above who were tested for cannabis at the time of initial evaluation were included in the study. Variables included in the study were: race, sex, injury severity score (ISS), Glasgow Coma Scale (GCS) Score, Abbreviated Injury Scale (AIS) score of different body regions and comorbidities. Excluded from the study were all patients who were not tested for cannabis or tested for cannabis but were also tested positive for alcohol and other drugs and those suffering from mental conditions. Propensity matched analysis was performed. The outcome of interest was overall in-hospital mortality and complications.

Results: Propensity matched analysis created 28,028 pairs. The analysis showed no significant difference in-hospital mortality between cannabis positive and cannabis negative groups (3.2% vs. 3.2%). The median length of hospital stay in both groups was not significantly different (4 [IQR: 3-8] vs. 4 [IQR: 2-8] days). No significant difference was found between the two groups regarding hospital complications except in pulmonary embolism (PE) with 0.1% less incidence of PE in the cannabis positive group compared to the cannabis negative group (0.4 vs. 0.5%). The incidence of DVT was identical in both groups (0.9% vs. 0.9%).

Conclusion: Cannabis was not associated with overall in-hospital mortality or morbidity. There was a slight decrease in the incidence of PE in the cannabis positive group.