Acta Neurochir (2005) [Suppl] 95: 299–301 6 Springer-Verlag 2005 Printed in Austria Cerebral haemodynamic assessment in patients with thalamic haemorrhage: a pilot study with continuous compliance monitoring S. C. P. Ng1, W. S. Poon1, and M. T. V. Chan2 1 Division of Neurosurgery, Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China 2 Department of Anaethesia and Intensive Care, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong, China Summary Objective. Thalamic brain haemorrhage is a common disabling and potentially fatal condition. However, management is mainly supportive, very rarely do neurosurgeons resort to evacuation of the haematoma. We hypothesised that cerebral haemodynamic abnor- malities in the forms of lost pressure autoregulatory response (PAR) and/or impaired cerebral vasoreactivity (CVR) to carbon di- oxide may indicate the haematoma should be aspirated to prevent further brain damage. Material and methods. Patients with thalamic haemorrhage were selected on clinical ground for intracranial pressure (ICP) monitor- ing and intensive care management. Spiegelberg double lumen intra- ventricular balloon catheter was inserted as any other fluid-filled ICP monitoring technique, on the side of the haematoma. Data of ICP, arterial blood pressure (ABP), cerebral perfusion pressure (CPP) and intracranial compliance were collected on a minute basis. Hourly averages were used for analysis. To assess PAR and CVR, blood flow velocity (BFV) in both middle cerebral arteries were measured continuously by transcranial Doppler (TCD) ultra- sonography. Results. Six patients with medium (15–25 ml) to large (>25 ml) haematoma volume were subjected to ultrasoud-guided aspiration. 51 CVR and 53 PAR tests were performed. 80820 sets of data were prospectively collected. Progressive reduction in ICP and sustained improvement in compliance and BFV were observed after aspira- tion. Impairment in PAR and/or CVR was consistent with clinical deterioration in four patients. Such disturbance was normalised after aspiration. Increments in BFV and improvement in compliance were demonstrated. Conclusions. Cerebral haemodynamic abnormalities in thalamic haematomas can be demonstrated by the non-invasive TCD ultra- sonograpy. These abnormalities can be corrected by aspiration of the haematoma, and hence improve intracranial compliance. Keywords: Thalamic haemorrhage; intracranial compliance; intra- cranial pressure monitoring; pressure autoregulatory response; cere- bral vasoreactivity; transcranial Doppler ultrasonography. Introduction Spontaneous intracerebral haemorrhage is twice more common in Southern Chinese than in Cauca- sians. Thalamic haemorrhage accounts for 32% of these patients with ICH [2] and carries a 35% manage- ment mortality [1]. In general, thalamic haemorrhage is complicated by intraventricular haemorrhage (IVH) with or without hydrocephalus. It causes more extensive and persistent in the metabolic depression and more pronounced cerebral blood flow (CBF) reduction, and therefore a worse outcome [3]. Nevertheless, management is mainly supportive and there is no rigid guideline for surgical intervention in treating these deep-seated haematoma. In order to improve the outcome, apart from monitoring the intracranial pressure (ICP), we may need more intensive monitoring to help clinical decision making in evacuating or aspirating the haematoma. Cerebral vasoreactivity (CVR) to carbon dioxide (CO 2 ) and pressure autoregulatory response (PAR) to cerebral perfusion pressure (CPP) alterations are physiological mechanisms that can have pro- found influence on CBF. These cerebral haemo- dynamic assessments in patients with traumatic brain injury, carotid stenosis and hydrocephalus have gained clinical importance. Continuous intracranial compliance monitoring provides information on the volume change resulting from unit change in pres- sure and helps to identify process which leads to raised ICP. In this pilot study with intracranial compliance monitoring, we hypothesised that cerebral haemody- namic abnormalities in the forms of lost PAR and/or impaired CVR may indicate the haemoatoma should be aspirated to prevent further brain damage.