To explore the predictive value of detection of Lac of arterial blood and PCT or combined detection for delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).

We collected randomly 70 patients with acute carbon monoxide poisoning (ACMP) who were received in hospital in our emergency department; all the patients were followed up for 3 months, 10 of the them presented with DEACMP enrolled in the DEACMP group, and the other 60 patients enrolled in the non DEACMP group. At the same time, 40 health examination personnel in the corresponding period were collected randomly as control group. All patients were tested Lac of arterial blood and PCT immediately when they were received in hospital. The sensitivity and specificity of Lac, PCT and combined detection of both for diagnosis of DEACMP were calculated.

Lac of arterial blood and PCT in the group of DEACMP were all higher at different levels than those in non DEACMP group and control group(rank sum test, P<0.05). The abnormal rates of the early detection of Lac and PCT were all higher significantly in DEACMP group than those in non DEACMP group, and the difference had statistical significance(chi-square test, P<0.05). The sensitivity about the elevation of Lac and PCT predicting DEACMP all was 90.0%, specificity was 50.0% and 65.0%, respectively; accuracy was 55.7% and 68.6%, respectively. If one item of combined detection was positive for predicting the occurrence of DEACMP, the sensitivity of combined detection was 100.0%, specificity was 41.7%, positive predictive value was 21.7%, negative predictive value was 100.0%, and accuracy was 71.4%.

Early index of Lac of arterial blood and PCT all increase at different levels in patients of DEACMP. The combined detection has more ideal predictive value than single index detection for predicting the occurrence of DEACMP.