[Patient posture in neurosurgery].
There is still controversy whether neurosurgical patients' head and trunc should be elevated or not, particularly in case of increased intracranial pressure (ICP). Head up position may have beneficial effects on ICP via changes in mean arterial pressure (MAP), airway pressure, central venous pressure and CSF displacement. However, in some circumstances, head up position may decrease MAP, which in turn will result in a paradoxical rise in ICP through autoregulation mechanisms. Therefore, the degree of head elevation has to be titrated by evaluating the most adequate cerebral perfusion pressure (CPP) for each patient by means of transcranial Doppler or measurement of jugular venous blood oxygen saturation. Head elevation above 30 degrees should be avoided in all cases. In most patients with intracranial hypertension, head and trunc elevation up to 30 degrees is useful in helping to decrease ICP, providing that a safe CPP of a least 70 mmHg or even 80 mmHg is maintained. Patients in poor haemodynamic conditions are best nursed flat. CPP is thus a most important factor to evaluate and monitor while considering head elevation in patients with increased ICP.
Bruder
N
N
Service d'Anesthésie-Réanimation, CHR La Timone, Marseille.
Ravussin
P
P
François
G
G
D001794:Blood Pressure; D002560:Cerebrovascular Circulation / Q000502:physiology; D006801:Humans; D007427:Intracranial Pressure / Q000502:physiology; D007432:Intraoperative Period; D009493:Neurosurgery; D011187:Posture
Position du patient en neurochirurgie.