Oxygen utilization coefficient in predicting the severity of critical illness

Objective To evaluate the role of oxygen utilization coefficient (O 2UC ) in predicting the severity of various diseases. Methods Gas analysis of arterial blood and central venous blood and calculation of O 2UC[O 2UC=(SaO 2-SvO 2)/SaO 2] were carried out in different groups ( group 1,16 cases of trauma, all survived ;group 2, 18 emergency cases undergoing cardiopulmonary resuscitation(CPR); group 3,13 cases undergoing CPR in intensive care unit, all died ; group 4,13 critically ill patients. Results O 2UC was 0.30±0.08,0 67±0.27 and 0.60±0.15 in the groups 1,2 and 3 respectively . The difference between group 1 and 2 was significant ( P 0.001). O 2UC persisted to increase, and maintained high for a long time (more than 8～12 hours), the prognosis of the patients was bad . The critical limitation of O 2UC was 0.40. In group 4 O 2UC was closely correlated with the severity of clinical condition. Conclusion O 2UC is a cconvienent , reliable and sensible predictor in the treatment of critically ill patients.