The prognostic value of the brain sodium-potassium ATPase enzyme concentration in head injury

Sodium-potassium adenosine triphosphatase (ATPase) enzyme was determined in the brain tissue of 11 patients with head injury and 6 control patients. Patients with head injury included in this study were selected from two categories: (a) patients in deep coma due to severe head injury Glasgow Coma Scale (GCS)<8; 6 cases]; (b) patients with depressed skull fractures with dural tears who were conscious and able to give an adequate verbal response (GCS>10; 5 cases). The level of the enzyme was significantly reduced in comatose patients with severe head injury as compared to the controls (P<0.001) or to conscious patients with depressed fractures (P<0.001). In the group of conscious patients with depressed fractures, the enzyme level was no different from that of the controls (P = 0.4215). All comatose patients with severely reduced enzyme levels subsequently died, whereas those with depressed fractures with normal enzyme levels survived. The relationship between a low enzyme level and brain edema in severe head injury is discussed.