Severe head injury: control of physiological variables, organ failure and complications in the intensive care unit

In patients with severe head injury, control of physiological variables is important to avoid intracranial hypertension and secondary injury to the brain. The aims of this retrospective study were to evaluate deviations of physiological variables and the incidence of extracranial complications in patients with severe head injury. We also studied if these deviations could be related to outcome.

One hundred and thirty-three patients were included during a 5-year period (1998-2002). Deviations from treatment goals for the following physiological variables were studied: blood pressure, haemoglobin, blood sugar, serum sodium, serum albumin and temperature. Extra cerebral organ complications were also recorded as well as outcome at 6 months.

The median age was 32 years (range; 1-88 years). Median Glasgow Coma Scale (GCS) before intubation was 6 (range; 3-14). The frequencies of severe deviations from the desired values of the physiological variables for at least one treatment day were: hypotensive episodes (systolic BP < 90 mmHg) - 20%, anaemia (hgb < 8 g/dL) - 22%, blood glucose > 10 mmol/l - 26%, serum sodium concentration < 130 mmol/l - 10%, serum albumin < 25 g/l(-1)- 31% and hyperthermia > 39 degrees C - 24%. Pneumonia was diagnosed in 71% and Acute Lung Injury (ALI)/Adult Respiratory Distress Syndrome (ARDS) in 26% of the patients. Other complications such as severe sepsis (6%), renal failure (1.5%), a coagulation disorder (6%) and liver failure (one patient) were infrequent. Age, GCS, hypotension during the first day of treatment, elevated blood sugar and low albumin predicted an unfavourable outcome.

Deviations of key physiological variables and pulmonary complications were frequent in patients suffering from severe head injury. During intensive care treatment, hypotension, elevated blood sugar and hypoalbuminemia are possible independent predictors of an unfavourable outcome.