[Efficacy of respiratory therapy/controlled hyperventilation in cerebral trauma]

In a prospective study in 129 patients with isolated head injury the efficacy of respiratory treatment/controlled moderate hyperventilation on the neurological outcome is to be tested. Indications for mechanical ventilation are either a bad neurological behaviour (GCS less than or equal to 5) or neurogenic-induced disturbances of pulmonary gas exchange. Both oxygenation and neurological behaviour are worse in the ventilated group than in patients breathing spontaneously. Therefore a direct and quantitative comparison between these two groups of patients is not possible; however, conclusions can be drawn on the efficacy of the respiratory management. Survival rate of all patients on discharge from ICU amounts to 61.2%; of the patients breathing spontaneously 96.1% survive the cerebral trauma, while only 39.7% of the ventilated patients survive. The post-traumatic course of the GCS-values shows a transient but statistically and clinically significant decrease for the nonventilated survivors, while a continuous increase can be demonstrated for the patients being ventilated and surviving the cerebral trauma (n = 31). The survival rate for the most severely injured and ventilated group (n =59; GCS less than or equal to 5) amounts to 38.9% (23/59 patients). Out of these 23 patients with initial extensor spasm 15 reach greater than or equal to 10 points on GCS-scale (12.2 +/- 0.5 P.) on discharge from ICU. An additional neurogenic-initiated respiratory failure increases the rate of mortality to a statistically significant extent (P less than 0.025). It is concluded that respiratory treatment with moderate hyperventilation positively influences the quality of the neurological outcome in patients with severe head injury.