[Tracheal gas insufflation associated with mechanical ventilation for CO2 removal]

[Tracheal gas insufflation avoids hypercapnia in patients with severe head trauma and acute lung injury]

PURPOSE

The purpose of the ventilatory management of acute respiratory distress syndrome (ARDS) is to avoid any barotrauma to the lungs by decreasing the tidal volume at the expense of permissive hypercapnia. This hypercapnia is extremely dangerous for severe head trauma patients because it increases intracranial pressure. The solution could be the use of tracheal gas which insufflation (TGI) allows the reduction of arterial carbon dioxide tension (PaCO(2)) while controlling airway pressures.

CLINICAL FEATURES

We report the cases of two patients with ARDS and severe head trauma. The decrease of tidal volume ( by 60 and 25% respectively) in association with tracheal gas insufflation allowed to reduce plateau airway pressure (<35 cm d'H(2)O) and PaCO(2) (in the first case by 23% and in the second case, by 11% for the second hour then by 24%), while intracranial pressure remained constant or was lowered (in the second case by 39% for the second hour). TGI consisted in insufflating fresh gas via a small catheter placed in the trachea (0(2) at 6 L*min(-1) in the first patient and 4 L*min(-1) in the second case).

CONCLUSION

TGI appears to be an important component of ventilatory management when ARDS is associated with severe head trauma.