The use of hyperventilation in the treatment of plateau waves in two patients with severe traumatic brain injury - Contrasting effects on cerebral oxygenation

We present the case reports of two patients with severe traumatic brain inj ury who, in the absence of external stimuli, developed episodes of acute el evation of intracranial pressure (plateau waves) associated with jugular bu lb oxyhemoglobin (SjO(2)) desaturation, severe reduction of cerebral tissue PO2 (PbrO(2)), and deterioration of neurological status. In all of these e pisodes hyperventilation was successful in extinguishing plateau waves, but in one patient it was associated with an improvement of both the global (i ncreased SjO(2)) and local (increased PbrO(2)) cerebral perfusion, while in the other patient it was associated with a reduction of both SjO(2) and Pb rO(2). In both patients the effects of hyperventilation (and other pharmaco logical treatments) were short-lived; plateau waves reappeared and the pati ents had to be submitted to decompressive craniotomy (first patient) and ce rebrospinal fluid (CSF) drainage (second patient). We conclude that hyperve ntilation can he useful as a temporary measure to treat plateau waves, but cerebral oxygenation should always be monitored to avoid iatrogenic cerebra l ischemia.