Fixed and dilated pupils after trauma, stroke, and previous intracranial surgery: management and outcome

Fixed and dilated pupils in comatose patients are well known to be related to a poor prognosis, especially when present bilaterally. 1-5 If not caused by local trauma or drug action, this symptom indicates injury or compression of the third cranial nerve and the upper brain stem, mainly caused by an extending intracranial mass lesion or by diffuse brain injury. 6-12 A recently suggested alternative or additional mechanism for mydriasis and brain stem symptomatology may be brain stem ischaemia. 13

Due to modern emergency guidelines nearly all patients with a history of head trauma or stroke with severe impairment of consciousness are sedated, intubated, and ventilated at the emergency site. On admission to hospital most of these patients are therefore not fully assessable, so that pupillary examination remains a major tool for clinical evaluation. The finding of unilaterally or bilaterally fixed and dilated pupils (FDPs) indicates an emergency situation, and decisions on diagnostic and therapeutic procedures are to be made quickly, mainly on the basis of the personal experience of the neurosurgeons on duty. The situation is even more difficult if the neurosurgeon is contacted by telephone from a distant hospital with limited diagnostic resources. On such occasions the pupillary finding may be the only reliable symptom to be reported. Although prognostic factors after severe head injury have been widely studied, 5 14-16 there is less information in the literature on the efficacy of neurosurgical therapy of any kind on outcome in the presence of FDPs. Moreover, the impact of different underlying causes is unclear-for example, trauma, stroke, or FDP occurring after elective intracranial surgery, the FDP indicating rebleeding or postoperative brain oedema. With socioeconomic aspects and limited resources in mind it would be helpful to know more about predictive factors for the outcome of patients with FDPs. Therefore, the goal of this study was to provide additional data for decision making in the treatment of patients presenting with FDPs due to cerebral herniation.

Methods

PATIENTS AND EXCLUSION CRITERIA

This consecutive series consisted of 99 patients (51 female, 48 male), mean age 48.5 years (range 0.2-87 years) presenting with or developing unilateral or bilateral FDPs due to an intracranial mass lesion. All such patients admitted between January 1995 and September 1996 to the Department of...