With the development of medical sciences and intelligent software, the amount of data acquired electronically from patients in intensive care unit (ICU) has grown exponentially, therefore they were susceptible to analysis by artificial neural network (ANN). ANN has been used in ICU in a variety of fashions, but most extensively for outcome prediction. ANN can function as intelligent assistant to clinicians, constantly monitoring electronic data streams for important trends. The integration of ANN into the ICU can be expected to make significant use of health resources and improve outcome of the patients.