Lactate Level Is More Significant Than Carboxihemoglobin Level in Determining Prognosis of Carbon Monoxide Intoxication of Childhood

Objectives To evaluate the demographics, risk factors, correlation between carbon monoxide (CO) level and clinical findings, and laboratory findings determining the prognosis and ischemic myocardial injury due to CO intoxication in patients admitted to pediatric emergency department. Materials and Methods Six hundred seventy-four patients were admitted with CO intoxication between May 2007 and October 2009, 288 patients who required hospitalization were enrolled into the study prospectively. Results Incidentally, 144 (50%) of the patients were evenly distributed as girls and boys. Their age ranged between 7 months and 17 years; mean age was 8.6 years. The mean CO level was 26.8. The high levels were detected regarding lactate in 199 (90.1%) patients, creatine kinase (CK)-MB in 130 (45.1%) patients, CK in 80 (27.8%) patients, cardiac Troponin I in 35 (17.2%) patients, and lactate dehydrogenase in 34 (15.7%) patients. There was a significant positive correlation when symptoms like syncope, loss of consciousness, and convulsion were compared with carboxyhemoglobin, lactate, CK, CK-MB, and lactate dehydrogenase levels (P < 0.05), whereas there was no correlation when compared with cardiac Troponin I (P > 0.05). To determine the accuracy of predicting severe CO intoxication, sensitivity of 52.6% and specificity of 85.7% were found in receiver operating characteristic analysis when the lactate level was 3.85 mmol/L, whereas sensitivity of 70.5% and specificity of 59.6% were found when the carboxyhemoglobin level was 27.1%. One hundred forty-six (%50.8) of the patients had normal electrocardiographic findings, whereas 135 (46.8%) had sinus tachycardia, 6 (2%) had right branch block, and 1 (0.34%) had atrioventricular block. In 34 patients who had high CK-MB and Troponin I levels, only sinus tachycardia was detected in electrocardiography, and there were no ST changes. Hyperbaric oxygen was necessary in 2 patients admitted with coma. Conclusions In children admitted because of CO intoxication, the blood lactate levels may give more accurate information in terms of loss of consciousness and convulsion, lactate level could be taken as a measure of severe poisoning and may help to decide for hyperbaric oxygen treatment.