What is permissive hypercapnia?
Permissive hypercapnia was recently introduced as an alternative modality in the treatment of neonates with CDH. Conventional ventilatory management resulted in baro-trauma to the lungs secondary to the high pressures needed to achieve adequate ventilation and oxygenation. In permis-sive hypercapnia, the arterial carbon dioxide tension (PaCO2) is allowed to rise while maintaining adequate oxygenation and acid-base balance. The goal is to maintain a preductal oxygen saturation of greater than 90%. Acid-base balance is maintained with either bicarbonate or tris(hydroxymethyl) aminomethane (THAM).