Association of Cigarette Smoking History With Drug Abuse History and Arterial Carboxyhemoglobin in Trauma Activation Patients: A Retrospective Study

Abstract

Introduction The relationship between cigarette smoking and arterial carboxyhemoglobin (CoHb) in trauma activation patients has not been investigated. The aim was to determine if cigarette smoking is associated with drug abuse history and arterial CoHb levels. Methodology This is a retrospective review of level I trauma center activations aged 18-60 during 2018-2020. A medical record audit was performed to assess each patient's cigarette smoking and drug abuse history and admission arterial CoHb level. The CoHb levels and smoking history for each patient were used to construct a receiver operating characteristic curve. Results Of the 742 trauma activations aged 18-60, 737 (99.3%) had a documented cigarette smoking history. Smoking history was positive in 49.7% (366) and negative in 50.3% (371). The positive smoking proportion was greater in patients with a drug abuse history (63.9% (234/366)) than those with a negative history (31.0% (115/371); p<0.0001; odds ratio=4.0). In 717 patients with a CoHb value, the CoHb was higher in smokers (3.9±2.2%) than in non-smokers (0.5±0.4%; p<0.0001; Cohen d=2.2). A CoHb >1.5% was higher in smokers (93.3% (333/357)) than non-smokers (1.7% (6/360); p<0.0001; odds ratio=818.6). The receiver operating characteristic curve for the relationship between CoHb and cigarette smoking history showed an area under the curve of 0.980 (p<0.0001). Using an arterial CoHb level >1.5% to predict a positive smoking history and a CoHb level ≤1.5% to predict a non-smoking history, sensitivity was 93.3% (333/357), specificity was 98.3% (354/360), and accuracy was 95.8% (687/717). Conclusion Cigarette smoking in trauma activations aged 18-60 is associated with drug abuse history and increased arterial CoHb levels on trauma center arrival.

Keywords: carboxyhemoglobin; cigarette smoking; drug abuse; trauma; trauma centers.

Figure 1. Relationship of arterial CoHb and cigarette smoking history

AUC, the area under the curve; CoHb, carboxyhemoglobin