[Central respiratory failure occurred in the subacute phase of unilateral Wallenberg's syndrome: a case report].

A 46-year-old man developed central respiratory failure in the subacute phase of unilateral lateral medullary infarction. He complained of sudden headache and nausea at first. Neurological examination revealed Wallenberg's syndrome. Acute right lateral medullary infarction caused by the dissecting right vertebral artery was identified by magnetic resonance images. He was transferred to our hospital on the 3rd day after the onset. He was alert and conscious on admission, and became restless gradually later. He was intubated for sudden respiratory failure on the 9th day. Blood gas analysis showed hypercapnia and hypoxia. Central respiratory failure was indicated by the fact that various examinations showed no change of his infarction, no subarachnoid hemorrhage, or no worsening of pneumonia. Ventilatory support was required for a month because of repetitive CO2 narcosis. He was weaned from the ventilator on the 39th day. Only a few reports are available on central respiratory failure associated with the subacute phase of unilateral medullary infarction. Delayed central respiratory failure may be lethal. Careful observation is required on the subacute phase of Wallenberg's syndrome.