ABSTRACT
PURPOSE@#The objective was to determine the association between PaCO₂ and adverse cardiovascular events (ACVEs) in carbon monoxide (CO)-poisoned patients.@*METHODS@#This retrospective study included 194 self-breathing patients after CO poisoning with an indication for hyperbaric oxygen therapy and available arterial blood gas analysis at presentation and 6 hours later. The baseline characteristics and clinical course during hospitalization were collected and compared. The mean PaCO₂ during the first 6 hours after presentation was calculated.@*RESULTS@#The incidence rates of moderate (30 mmHg< PaCO₂<35 mmHg) or severe (PaCO₂≤30 mmHg) hypocapnia at presentation after acute CO poisoning were 40.7% and 26.8%, respectively. The mean PaCO₂ during the first 6 hours was 33 (31–36.7) mmHg.The incidence of ACVEs during hospitalization was 50.5%. A significant linear trend in the incidence of ACVEs was observed across the total ranges of PaCO₂ variables. In multivariate regression analysis, mean PaCO₂ was independently associated with ACVEs (OR 0.798 (95% CI 0.641–0.997)).@*CONCLUSION@#Mean PaCO₂ during the first 6 hours was associated with increased ACVEs. Given the high incidence of ACVEs and PaCO₂ derangement and the observed association between PaCO₂ and ACVEs, this study suggests that 1) PaCO₂ should be monitored at the acute stage to predict and/or prevent ACVEs; and 2) further study is needed to validate this result and investigate early manipulation of PaCO₂ as treatment.