Refractory Central Neurogenic Hyperventilation: A Novel Approach Utilizing Mechanical Dead Space

Abstract

This report describes the successful management of a case of central neurogenic hyperventilation (CNH) refractory to high dose sedation by increasing the mechanical dead space. A 46-year-old male presented with a history of multiple neurological symptoms. Following an extensive evaluation, he was diagnosed with primary diffuse CNS lymphoma and started on high dose steroids. After initial symptomatic improvement, the patient developed increasing respiratory distress and tachypnea. He was intubated and transferred to the neurointensive care unit (neuro ICU). While in the ICU the patient remained ventilator dependent with significant tachypnea and respiratory alkalosis resistant to fentanyl and propofol. This prompted an attempt to normalize the PaCO₂ via an increase of the mechanical dead space. This approach successfully increased PaCO₂ and bridged the patient until ongoing therapy for the underlying disease resolved the pervasive breathing pattern typical of CNH. Further investigation is warranted to evaluate this strategy, which upon review of the literature appears underused.

Keywords: central neurogenic hyperventilation; critical care; lymphoma; mechanical ventilation; neuro-oncology; neurocritical care.

Figure 1

Fluid attenuated inversion recovery (FLAIR) demonstrating pontine hyperintensity from lymphoma involvement.