Ketamine - a drug with various actions and just as many opinions on it. One concern often mentioned is that ketamine might cause a raise in intracranial pressure (ICP) and therefore is often avoided in this group of patients. In May's Journal of Anaesthesia Wang et al. looked at the existing evidence on this topic. They ended up with 5 trials meeting their inclusion criteria on administration of ketamine and the ICP levels within the first 24h as a primary outcome.
To make it short: Ketamine does not increase ICP in comparison to opioids. They conclude that ketamine should not be discouraged on the basis of ICP-related concerns.
Wang et al. J Anaesth. 2014 May 24