A Carbon Monoxide Breathalyzer is Effective at Identifying Smokers Before Total Joint Arthroplasty

Background Smoking is a major risk factor for delayed wound healing and prosthetic joint infections, yet it is poorly identified and modified before surgery. Patients often omit or downplay their consumption, and objective methods of screening for smoking are lacking. Carbon monoxide (CO) breath testing is a validated, noninvasive tool to detect recent smoking but has yet to be used to screen patients planned for total joint arthroplasty (TJA). This study compares self-reported smoking status to a CO breathalyzer test in patients listed for TJA. Methods We conducted a cross-sectional study of patients with end-stage arthritis listed for TJA surgery at a single academic center. All participants completed a standardized smoking questionnaire and then underwent CO breath testing using a validated handheld breathalyzer. CO levels were categorized as low (0-6 ppm), borderline (7-9 ppm), or high (≥10 ppm). The primary outcome was the concordance between self-reported smoking status and CO levels. Results A total of 153 patients were enrolled, of whom 29 self-identified as active smokers , 14 as exposed nonsmokers ( ENS ), and 110 as nonsmokers . Smokers exhibited the highest mean CO levels (13.6 ± 7.5 ppm), followed by ENS patients (9.0 ± 7.4 ppm), while nonsmokers had significantly lower levels (1.6 ± 1.6 ppm; P < .001). In the ENS group, 42.9% had high CO levels, indicating possible discordance between self-report and biochemical testing. Conclusions CO breath testing is a low-cost, noninvasive tool that successfully differentiated between self-reported active smokers and nonsmokers among patients who are planned to undergo a TJA. Some patients who identified as nonsmokers with an unclear exposure history were found to have high CO levels upon testing. Integrating CO screening into preoperative assessment may enhance identification of recent smoke exposure and support targeted counseling prior to TJA.