Cerebral perfusion pressure management of severe diffuse head injury: effect on brain compliance and intracranial pressure.
BACKGROUND
Cerebral perfusion pressure management (CPPM) is an accepted modality of treatment of severe diffuse head injury (SDHI). However, CPPM has the potential to cause transcapillary exudation in the presence of a disrupted blood brain barrier and can lead to further increase of intracranial pressure (ICP) and worsening of compliance.


OBJECTIVE
This study attempts to evaluate the effect of both transient and prolonged changes in cerebral perfusion pressure (CPP) on ICP and cerebral compliance as measured by the Pressure Volume Index (PVI), and to correlate changes in PVI with outcome at 12 months using the Glasgow Outcome Score.


METHODS
Prospective study in a neurosurgical ICU.


METHODS
Twenty-seven SDHI patients managed using standard protocol to maintain CPP above 70 mmHg. Mean arterial pressure (MAP), ICP and CPP were monitored every half-hour. Daily monitoring of the PVI and ICP was done before, and after the induced elevation of MAP using IV Dopamine infusion. The relationship between CPP, MAP, ICP, PVI and outcome was evaluated.


METHODS
The paired and independent samples T-test, and the Pearson correlation coefficient.


RESULTS
CPPM rarely leads to progressive rise in ICP. Maintaining CPP above 70mmHg does not influence ICP or PVI. Transient elevations in CPP above 70mmHg may produce a small rise in ICP. Trend of change in PVI influenced outcome despite similar ICP and CPP.


CONCLUSIONS
Elevating the CPP above 70mmHg does not either reduce the ICP or worsen the compliance. Monitoring changes in compliance should form an integral part of CPPM.
Pillai
S
S
Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, India. drshibupillai@hotmail.com
Praharaj
S S
SS
Rao
G S U
GS
Kolluri
V R S
VR
D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D001921:Brain / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003187:Compliance; D005260:Female; D023261:Glasgow Outcome Scale; D016489:Head Injuries, Closed / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007427:Intracranial Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D016896:Treatment Outcome