Bedeutung der somatosensibel evozierten Potentiale (SEP) bei der Feststellung des Hirntodes

Effect of Pyritinol on EEG and SSEP in Comatose Patients in the Acute Phase of Intensive Care Therapy

“…Table 3 shows that measurement of the latencies, amplitudes, and central conduction times revealed similar changes during and directly after administration of pyritinol, with shortened latency and conduction time, and with an increase in amplitudes, even though the EEG showed a desynchronization effect in the sense of enhanced vigilance. Only one patient (GCS 3), with massive brain swelling due to vasospasm after subarachnoid hemorrhage and infaust prognosis, presented with a different behavior (in accordance with the observations made by Stöhr et al (1987).…”

“…25 (1992) evoked brainstem potentials and medianus-evoked somatosensory cortical potentials have proved useful for the specific monitoring of certain functions of individual afferent conduction paths in the brain; the additional recording of spinal SEP responses permits stimulus conduction to the upper part of the medulla, and from there to the cerebral cortex, to be differentiated. This differentiation is of particular prognostic significance (Jörg, 1983;Riffel et al, 1987;Haupt et al, 1988;Stöhr et al, 1985); in particular the central conduction time, calculated from the latency between cervical and cortical stimulus response, permits a prognostic statement (Buettner et al, 1985;Ferbert et al, 1985). For exampIe, hypoxic brain damage shows an early corre1ation between the extent of the SEP changes and prognosis (Schoepfr ner, 1987).…”

“…While neurological findings and the EEG are to some extent limited in their informative value by the administration of sedatives, hypnotics, and muscle relaxants to ventilated patients as well as by the administration of barbiturates to reduce the cerebral metabolism, early evoked potentials are only affected insignificantly by drugs (Riffel, 1987;Stöhr et al, 1985). Today, early evoked potentials, in addition to EEG recording and registration of intracranial pressure, are therefore a firm part of neuromonitoring within the frame of intensivecare therapy of comatose patients after head injury or stroke.…”

Zum Problem primär erloschener evozierter zerebraler Potentiale in der Hirntoddiagnostik

“…Evozierte zerebrale Potentiale haben sich als cine einfachc und zuverlässige Methode zum Nachweis des Funktionsausfalls des Gehirns im Rahmen der Hirntoddiagnostik erwiesen ( I , 5.8, 10, I 1). Die Reaktionspotentialc sind deutlich wenigcr empfindlich als das EEG gegenüber Medikamenteneffekten und elektrischen Störfeldern der Umgebung (9). Gegenüber der Angiographie als Nachweismethodc für den eingetretenen Hirntod ergeben sich ebenfalls Vorzüge, die sich unter anderem in einer geringeren Belastung und Gefihrdung des Kranken äußern.…”