Central neurogenic hyperventilation in a conscious child associated with glioblastoma multiforme

Central neurogenic hyperventilation refers to progressive tachypnea leading to hypocarbia and respiratory alkalosis caused by cortical disorders, initially reported in comatose patients with mainly pontine infarction. Central neurogenic hyperventilation in conscious patients is even rarer, numbering around 30 reported cases including seven children, mainly associated with infiltrative gliomas and lymphomas of the brainstem and pons. We report the evolution of central neurogenic hyperventilation in a conscious child associated with an infiltrative glioblastoma multiforme diagnosed 1 year before admission. He presented with progressive tachypnea and dyspnea of 1 week duration. On examination he was fully alert and aware of his respiratory disorder. Respiratory rate was 56 breaths per minute using accessory respiratory muscles. Hyperventilation was unchanged during sleep. Arterial blood gases disclosed marked hypocarbia: Pco(2) of 8 mm Hg resulting in severe respiratory alkalosis at pH of 7.8. Central neurogenic hyperventilation was therefore suggested after exclusion of other respiratory or cardiac disorders. The exaggerated tachypnea persisted along with respiratory alkalosis. Over a period of 2 months his overall state markedly deteriorated; he lapsed into coma, and finally succumbed after involvement of medullary cardiovascular centers. Although extremely rare in the pediatric age group, central neurogenic hyperventilation should be suspected in any alert child presenting with unexplained increasing tachypnea and hypocarbia leading to respiratory alkalosis. The evolution of such a disorder may be an alarming sign of ensuing deterioration in patients with tumors of the brainstem and medulla before cardiovascular derangement.