title: Prolonged post-hyperventilation apnea in two young adults with hyperventilation syndrome.
abstract: BACKGROUND
  The prognosis of hyperventilation syndrome (HVS) is generally good. However, it is important to proceed with care when treating HVS because cases of death following hyperventilation have been reported. This paper was done to demonstrate the clinical risk of post-hyperventilation apnea (PHA) in patients with HVS.
  
  
  METHODS
  We treated two patients with HVS who suffered from PHA. The first, a 21-year-old woman, had a maximum duration of PHA of about 3.5 minutes and an oxygen saturation (SpO2) level of 60%. The second patient, a 22-year-old woman, had a maximum duration of PHA of about 3 minutes and an SpO2 level of 66%. Both patients had loss of consciousness and cyanosis. Because there is no widely accepted regimen for treating patients with prolonged PHA related to HVS, we administered artificial ventilation to both patients using a bag mask and both recovered without any after effects.
  
  
  CONCLUSIONS
  These cases show that some patients with HVS develop prolonged PHA or severe hypoxia, which has been shown to lead to death in some cases. Proper treatment must be given to patients with HVS who develop PHA to protect against this possibility. If prolonged PHA or severe hypoxemia arises, respiratory assistance using a bag mask must be done immediately.
authors.affiliation: Department of Domestic Science, Kagoshima Women's College, 6-9 kourai-chou, Kagoshima, 890-8520, Japan. munemoto8214@jkajyo.ac.jp.
authors.forename: Takao
authors.initials: T
authors.lastname: Munemoto
authors.forename: Akinori
authors.initials: A
authors.lastname: Masuda
authors.forename: Nobuatsu
authors.initials: N
authors.lastname: Nagai
authors.forename: Muneki
authors.initials: M
authors.lastname: Tanaka
authors.forename: Soejima
authors.initials: S
authors.lastname: Yuji