Respiratory control and respiratory sensation in a patient with a ganglioglioma within the dorsocaudal brain stem.
We encountered a young woman with severe central sleep apnea caused by a medullary glioma located slightly dorsal to and to the right of the midline, a region not generally associated with CO(2) chemosensitivity. The patient had normal spirometric readings, lung volumes, diffusing capacity, maximal inspiratory pressure, and alveolar-arterial oxygen difference. While awake, she displayed marked irregularity in her breathing pattern; her end-tidal CO(2) (FET(CO(2))) ranged from 5.3 to 10.9%. During voluntary hyperpnea, she could quickly reduce her FET(CO(2)) to 4.2%, but her PCO(2) did not change after administration of acetazolamide or progesterone. Like patients with congenital central hypoventilation syndrome (CCHS), our patient had a relatively intact ventilatory response to exercise; her PCO(2) was high at the start of exercise and increased slightly thereafter. In contrast to CCHS patients, however, our patient had an intact hypoxic ventilatory response (DeltaVE/ DeltaSa(O(2)) = -0.37 L/min/Sa(O(2))). In further contrast to CCHS patients, our patient had a very short breathholding time and described a sensation of air hunger as the factor limiting her breathholding ability. Her heart rate and blood pressure responses to the Valsalva maneuver were normal.
Manning
H L
HL
Departments of Medicine and Physiology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03765, USA. Harold.L.Manning@Hitchcock.org
Leiter
J C
JC
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D020295:Brain Stem Neoplasms / Q000175:diagnosis / Q000503:physiopathology*; D002245:Carbon Dioxide / Q000097:blood; D002628:Chemoreceptor Cells / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D018303:Ganglioglioma / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008526:Medulla Oblongata / Q000473:pathology / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood; D012123:Pulmonary Ventilation / Q000502:physiology; D020182:Sleep Apnea, Central / Q000175:diagnosis / Q000503:physiopathology*
D002245:Carbon Dioxide; D010100:Oxygen