de Picciotto Carole, Duménil Coraline, Auzel Olivier, Giraud Violaine, Bonay Marcel
Service de Physiologie-Explorations Fonctionnelles, Hôpital Ambroise Paré, Assistance Publique-Hôpitaux de Paris, Boulogne, France.
Service de Pneumologie, Hôpital Ambroise Paré, Assistance Publique-Hôpitaux de Paris, Boulogne, France.
J Med Case Rep. 2017 Aug 23;11(1):234. doi: 10.1186/s13256-017-1393-1.
Noninvasive positive pressure ventilation is frequently prescribed to obese patients with obstructive sleep apnea syndrome and obesity hypoventilation syndrome. However, mechanical ventilation with a positive end-expiratory pressure can induce or worsen a right-to-left shunt through a patent foramen ovale associated with systemic hypoxemia. Thus, in obese patients treated with noninvasive positive pressure ventilation, a paradoxical worsening of hypoxemia may reveal the existence of a patent foramen ovale.
A 50-year-old African woman was referred to our sleep center for severe obstructive sleep apnea syndrome and obesity hypoventilation syndrome. Because she had alveolar hypoventilation and had failed previous obstructive sleep apnea syndrome therapy, noninvasive positive pressure ventilation was started. In May 2015, she had a normal residual apnea/hypopnea index calculated by the ventilator software with no hypoventilation. Six months later, severe hypoxemia without hypercapnia was noted. Contrast transthoracic echocardiography showed right-to-left shunt through a patent foramen ovale. This finding prompted a decrease in expiratory and inspiratory positive airway pressures, after which the ventilator software recorded a normal residual apnea/hypopnea index and the blood gas values improved.
Noninvasive positive pressure ventilation therapy for combined obstructive sleep apnea syndrome and obesity hypoventilation syndrome must be monitored by arterial blood gas measurements, both to reassess the hypercapnia and to look for worsening hypoxemia due to a patent foramen ovale.
无创正压通气常用于患有阻塞性睡眠呼吸暂停综合征和肥胖低通气综合征的肥胖患者。然而，呼气末正压机械通气可通过与全身性低氧血症相关的卵圆孔未闭诱发或加重右向左分流。因此，在接受无创正压通气治疗的肥胖患者中，低氧血症的反常恶化可能提示卵圆孔未闭的存在。
一名50岁的非洲女性因严重阻塞性睡眠呼吸暂停综合征和肥胖低通气综合征被转诊至我们的睡眠中心。由于她存在肺泡低通气且先前阻塞性睡眠呼吸暂停综合征治疗失败，遂开始无创正压通气治疗。2015年5月，通过呼吸机软件计算得出其残余呼吸暂停/低通气指数正常，且无低通气情况。6个月后，发现存在无高碳酸血症的严重低氧血症。经胸超声心动图造影显示通过卵圆孔未闭存在右向左分流。这一发现促使降低呼气和吸气气道正压，之后呼吸机软件记录的残余呼吸暂停/低通气指数正常，且血气值有所改善。
对于合并阻塞性睡眠呼吸暂停综合征和肥胖低通气综合征的患者，无创正压通气治疗必须通过动脉血气测量进行监测，以便重新评估高碳酸血症，并查找因卵圆孔未闭导致的低氧血症恶化情况。
