Comparison of nurse and computer recording of ICP in head injured patients

The importance of intracranial pressure monitoring in management and study of the head-injured patient is clearly recognized by the clinician responsible for intensive care. However, in many institutions studies requiring quantitative measures of ICP in head-injured patients are limited by lack of sophisticated computer monitoring equipment. In this study we tested the ability of the nurse to describe ICP course by manual record and compared these results with an on-line computerized ICP monitoring system. The nurse recorded a single "end-hour" value of ICP from the bedside monitor while the computer averaged 720 data samples of ICP during the hour. Our results obtained from five head-injured patients undergoing ICP monitoring showed 55% of the 347 data points had a difference in ICP of 0.01 to 3.0 mm Hg and 38% differed between 3.01 and 6 mm Hg. In comparison, 84% of nurse observations were within 6 mm Hg. Comparison of the temporal course of nurse and computer ICP values combined with the frequency distribution of error data indicates the nurse "end-hour" value is a reasonable estimate of the patient's mean ICP for the entire hour as measured by the computer. Nurses can now ask questions regarding various aspects of a patient's ICP course and compare data with other groups as long as the method of data collection is defined in the same manner.