Prognostic and clinical relevance of pupillary responses, intracranial pressure monitoring, and brainstem auditory evoked potentials in comatose patients with acute supratentorial mass lesions.

Abstract

To test the hypothesis that the clinical condition and outcome in patients with acute supratentorial mass lesions can be assessed by determination of pupillary abnormalities, measurement of intracranial pressure, and results of brainstem auditory evoked potentials. Prospective case series of 55 patients presenting with supratentorial mass lesions. Neurologic and neurosurgical intensive care unit of a tertiary care center. Fifty-five comatose patients (26 female/29 male; 9 to 70 yrs of age [mean 44]). Pupillary abnormalities were rated "normal," "unilaterally enlarged," "unilaterally fixed," and "bilaterally abnormal." The outcome was rated using the Glasgow Outcome Scale. Intracranial pressure values were graded into five categories. Brainstem auditory evoked potentials were rated "bilaterally normal," "unilaterally abnormal," or "bilaterally abnormal," according to normative data. Statistical evaluation was performed by frequency analysis (Fisher's exact test, two-tailed) and calculation of contingency coefficients. Outcome was poor in 24 patients, good in eight patients, and 23 patients were severely disabled. Statistical analysis showed prognostic significance of both pupillary abnormalities (p = .0000542; contingency coefficient = .589) and increased intracranial pressure (p = .0084; contingency coefficient = .352). Brainstem auditory evoked potential categories correlated significantly with pupillary abnormalities (p = .000276; contingency coefficient = .505) and increased intracranial pressure (p = .0301; contingency coefficient = .502) but did not predict outcome (p = .645; contingency coefficient = .321). Pupillary abnormalities may serve as a reliable parameter, which may even be superior to brainstem auditory evoked potential testing and intracranial pressure monitoring for prediction of outcome in comatose individuals with supratentorial mass lesions. Brainstem auditory evoked potentials can be used to support the clinical relevance of abnormal pupillary status and increased intracranial pressure but are of no prognostic value. Increased intracranial pressure is associated with abnormalities in pupillary status and brainstem auditory evoked potentials. Examination for pupillary abnormalities in combination with intracranial pressure monitoring and brainstem auditory evoked potential testing seems to be a useful strategy in managing patients with supratentorial mass lesions in critical care units.