49 NON-INVASIVE DEMONSTRATION OF INTRACRANIAL PRESSURE DYSREGULATION IN FULMINANT HEPATIC FAILURE

In patients with fulminant hepatic failure (FHF), elevations of intracranial pressure (ICP) occur in the abscence of focal cerebral lesions. While monitoring of ICP with invasive methods is readily applied to e.g. neurosurgical patients, in FHF cranial surgical procedures are troublesome. A new non-invasive tool, the detection of enlarged optic nerve sheaths (ONS), is applied as a alternative in these patients. By ultra-sound methods, the onset of pathological findings of ONS was shown to concide with elevated ICP (1). By transorbital B-Scan (7.5 MHz), the optic nerve entry zone can be imaged precisely to allow reproducable measurements of transverse dural sheath diameters (ONSD, given in mm). In total, 54 children have been investigated on the intensive care unit (n=38 with raised ICP, 16 age matched children served as controls). Out of these, 12 children suffered from FHF. 6 patients died from ICP-dysregulation as confirmed by neurological and typical transcranial Doppler ultrasound findings. All patients with significant clinical deterioration and evidence of ICP elevations (n=38) developed dilated optic nerve sheaths (range:4.5-6.8 mm), taking 4.5 mm as upper normal limits as measured in normal controls. None of the patients with favourable outcome (n=24) showed progressive sheath enlargement along the course. Papilledema was constantly absent in these cases, indicating longer intervals for diagnostic findings to be demostrated by fundoscopy. On the basis of these preliminary data, we conclude, that monitoring of ONSD-measurements in these critically ill patients with FHF delivers essential information with regard to manifestation and course of ICP. In this sense, prolonged demonstration of dilated ONS may be a marker for progressive deterioration due to intracranial complication of FHF. Monitoring of ONSD thus may be an important tool for decision making in transplantation of these patients.