Analysis of abnormal jugular bulb oxygen saturation data in patients with severe head injury.

Jugular bulb oximetry provides the first bedside, continuously available information on cerebral perfusion adequacy. An extensive analysis was made of all jugular bulb oxygen saturation (SjO2) data obtained in 50 patients suffering from severe head injury. A total of 176 periods (more than 30 minutes) with reliable, abnormal SjO2-values was observed, with 62 desaturation periods (SjO2 < 55%) and 114 high SjO2-periods (SjO2 > 80%). Jugular desaturation periods were predominantly observed in the first 2 days of monitoring and seemed the most closely correlated to lowered cerebral perfusion pressure and lowered arterial carbon dioxide tension. The high SjO2-values were more equally distributed over the first 5 days of monitoring and seemed mostly correlated to increased arterial carbon dioxide tension. Highlights of the general management of severely head injured patients is discussed, focussing attention on the importance of cerebral perfusion pressure and normoventilation.