28 Feb Pupillary reactivity as an early indicator of increased intracranial pressure: The introduction of the Neurological Pupil index
Pupillary reactivity as an early indicator of increased intracranial pressure: The introduction of the Neurological Pupil index
Category: Critical Care
Chen JW, Gombart ZJ, Rogers S, Gardiner SK, Cecil S, Bullock RM. Pupillary reactivity as an early indicator of increased intracranial pressure: The introduction of the neurological pupil index. Surg Neurol Int 2011;2:82.
Abstract
Background:
This paper introduces the Neurological Pupil index (NPi), a sensitive measure of pupil reactivity and an early indicator of increasing intracranial pressure (ICP). This may occur in patients with severe traumatic brain injury (TBI), aneurysmal subarachnoid hemorrhage, or intracerebral hemorrhage (ICH). Methods: 134 patients (mean age 46 years, range 18–87 years, 54 women and 80 men) in the intensive care units at eight different clinical sites were enrolled in the study. Pupillary examination was performed using a portable hand-held pupillometer. Results: Patients with abnormal pupillary light reactivity had an average peak ICP of 30.5 mmHg versus 19.6 mmHg for the normal pupil reactivity population (P = 0.0014). Patients with “nonreactive” pupils had the highest peaks of ICP (mean = 33.8 mmHg, P = 0.0046). In the group of patients with abnormal pupillary reactivity, we found that the first evidence of pupil abnormality occurred, on average, 15.9 hours prior to the time of the peak of ICP. Conclusions: Automated pupillary assessment was used in patients with possible increased ICP. Using NPi, we were able to identify a trend of inverse relationship between decreasing pupil reactivity and increasing ICP. Quantitative measurement and classification of pupillary reactivity using NPi may be a useful tool in the early management of patients with causes of increased ICP.