CEREBRAL PERFUSION-PRESSURE AND INTRACRANIAL-PRESSURE IN RELATION TO NEUROPSYCHOLOGICAL OUTCOME

Objective: The study attempted to examine the relationship between neu ropsychological functioning and reduced cerebral perfusion pressure (C PP), raised intracranial pressure (ICP), and reduced mean arterial pre ssure (MAP), monitored during intensive care treatment. Design: This p rospective follow-up study included consecutive patients and evaluated outcome at 6 months postinjury by the administration of a neuropsycho logical test battery. Setting: The study was conducted at the Universi ty Hospital of Gent, Belgium. Patients and participants: Over a 30-mon th period, 43 patients were included. Inclusion criteria were the foll owing: hospital admission following closed head injury, ICP monitoring , no medical history of central nervous system disease or mental retar dation, survival for at least 6 months, and informed consent for parti cipation. Interventions: All patients received the hospital's standard treatment for head injury, which remained unchanged during the study period. Measurements and results: Reduced CPP was analyzed using the n umber of observed values below 70 mmHg, raised ICP using the number of values above 20 mmHg, and MAP using the number of values below 80 mmH g. The neuropsychological test battery included 11 measures of attenti on, information processing, motor reaction time, memory, learning, vis uoconstruction, verbal fluency, and mental flexibility. No linear rela tionships were found between overall neuropsychological impairment and episodes of reduced CPP, raised ICP, or reduced MAP. Conclusions: Alt hough reduced CPP and raised ICP are frequent, often fatal, complicati ons of head injury, in survivors they do not seem to be related to lat er neuropsychological functioning.