Arterial blood gas analysis in risk stratification of acute carbon monoxide poisoning.

This single-centre retrospective cohort study demonstrates that arterial blood gas (ABG) parameters independently stratify ICU admission risk in acute carbon monoxide poisoning (ACOP) beyond carboxyhemoglobin (COHb). Among 124 ACOP patients, the acidosis group (pH<7.35) had a higher ICU admission rate [44.8%, 95% Confidence Interval (CI): 26.8%∼63.7%] than the normal pH (17.7%, 95%CI: 10.1%∼27.5%) and alkalemia groups (12.5%, 95%CI: 1.6%∼38.3%, P<0.001), with a median COHb of 33.1%. The acidosis group presented severe metabolic disturbance (median lactate 7.60 mmol/L, GCS 7). Spearman analysis showed arterial lactate was more strongly associated with disease severity markers than COHb. Multivariate logistic regression confirmed GCS score, COHb, arterial lactate, and HCO3 as independent predictors for ICU admission.