The relationship between blood lactate, carboxy-hemoglobin and clinical status in CO poisoning

We aimed to determine the relationship between blood lactate, carboxy-hemoglobin (COHb) levels and the severity of clinical findings in patients with CO poisoning.

Patients over 18 years old and of both gender who were admitted to Emergency Department with the diagnosis of CO poisoning between 10.02.2008 and 17.03.2011 were enrolled in this study. Detailed physical examination of each patient was performed, patients and their relatives were informed about the study and written consents were noted. The levels of consciousness, physical examination findings, electrocardiographic findings, Glasgow Coma Scale (GCS) scores, laboratory results (lactate, COHb, CK-MB, Troponin-I levels) and applied treatments [normobaric oxygen therapy (NBOT), hyperbaric oxygen therapy (HBOT)] were recorded to standart data entry form for each patient. "SPSS for Windows version 18" package program was used for statistical analysis of the data.

Total 201 patients were included in this study. Thirty five patients (17.4%) received HBOT and lactate; COHb, CKMB, Troponin-I levels of this group were higher than the other patients. Lactate and COHb levels were statistically significantly higher in patients with GCS < 15 than the ones with GCS = 15 (p < 0.01). The patients whose both Troponin-I and CK-MB levels increased have higher lactate levels (p = 0.038), but COHb levels of these patients did not change (p = 0.495).

According to our study, blood lactate and COHb levels were both correlated with the changes of consciousness in CO poisoning. Blood lactate levels together with COHb in defining indications for HBO treatment might be suggested.