Iatrogenic withdrawal symptomes has been associated with prolonged mechanical ventilation and the and the derived symptoms such as fever and agitation has been shown to cause significantly prolonged ICU and hospital length of stay. The incidence of IWS in the adult general ICU ranges from 16,7-55%. To this date, the incidence of IWS has not been studied in patients with TBI.

Inclusion Criteria:

• adult patients suffering from severe TBI and were mechanical ventilated and received continuous infusions of opioids, benzodiazepines and neuromuscular blocking agents for 72ours or more

Exclusion Criteria:

• age <18 years, patients who died before discharge, chronic alcohol abuse, regular use of heroin, cocaine and amphetamines, chronic use of opioids, patient that were primary admitted to other ICUs and patients that were moved to other ICUs with ongoing infusions.

Severe TBI defined as traumatic brain injury that required admission to the neuro-ICU.