title: Uncontrollable high-frequency tachypnea in a case of unilateral medial medullary infarct.
abstract: BACKGROUND
  Medullary infarcts can be associated with breathing disorders that usually consist in central hypoventilation.
  
  
  METHODS
  We describe the case of a 54-year-old man, fully conscious, presenting with an uncontrollable high frequency and shallow tachypnea (95/min) at the onset of a unilateral medial medullary infarct. This disorder disappeared under inspiratory pressure support mechanical ventilation.
  
  
  RESULTS
  Respiratory drive (respiratory rate, occlusion pressure, and mean inspiratory flow), efferent pathway (transcranial and cervical magnetic stimulation), and afferent pathway (response to CO(2) and to lung inflation) were investigated. The respiratory drive was increased. The phrenic nerve conduction time was normal. The sensitivity of the central pattern generator to lung inflation and to CO(2) was preserved. The territory of the infarct was supplied by the spinal anterior artery.
  
  
  CONCLUSIONS
  An extremely rapid and shallow tachypnea due to the increase in respiratory drive can be associated with unilateral medullary infarction.
authors.affiliation: Département d'Anesthésie-Réanimation-SMUR, Hôpital Lariboisière, Assistance Publique-Hôpitaux de Paris, 2 rue Ambroise Paré, 75010 Paris, France. laurent.ducros@lrb.ap-hop-paris.fr
authors.forename: Laurent
authors.initials: L
authors.lastname: Ducros
authors.forename: Katayoun
authors.initials: K
authors.lastname: Vahedi
authors.forename: Thomas
authors.initials: T
authors.lastname: Similowski
authors.forename: Marie-Germaine
authors.initials: MG
authors.lastname: Bousser
authors.forename: Didier
authors.initials: D
authors.lastname: Payen
mesh_terms: D002544:Cerebral Infarction / Q000150:complications* / Q000503:physiopathology; D004562:Electrocardiography; D004576:Electromyography; D006801:Humans; D006935:Hypercapnia / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial