What vasopressor do you routinely use in the management of traumatic brain injury patients? Admittedly, in my neurocritical care practice, I don’t manage a lot of true TBI patients. In our system, the only neurotrauma patients that come to the neuro ICU are isolated neurotrauma (brain and/or spine without other major trauma). Polytrauma patients go to the trauma service and are comanaged in the TICU along with neurosurgery.
But, in my limited experience, I typically use norepinephrine. I might have formerly said phenylephrine, as that used to be the vasopressor of choice in the neuro ICU. This was mostly due to the fact that at one point, we were mostly using vasopressors to augment BP in order to increase perfusion to the brain or spine, a practice that has largely fallen out of favor. In these cases, the patients often just needed short runs of low dose pressor and so phenylephrine was considered safer to run without a central line, making it appealing in this subset.
But, in the past few years, we’ve gradually shifted away from this to favoring norepinephrine. I think this is largely because we’ve seen a steady increase in the overall acuity of the patients and now those who need pressors typically need them for actual shock, not just to drive MAPs. In that case, central access is typically needed anyway, eliminating the one benefit of phenylephrine.
In this episode of the Elective Rotation podcast, Pharmacy Joe covers a recent study in Anesthesia and Analgesia that seems to favor the use of phenylephrine as the first line vasopressor in TBI patients. It was a rather large retrospective study that showed a statistically significant increase in in-hospital mortality in patients who received norepinephrine as compared to those who received phenylephrine. The study found that norepinephrine was much more common in sicker patients (higher ISS, use of ICP monitoring, comorbidities, etc.), but the authors used propensity-matching statistical analysis to account for this.
Overall, it is an interesting study but there are number of issues including incomplete data regarding shock states. Despite the propensity-matching analysis, I think it’s reasonable to assume that there is probably some bias with patients receiving norepinephrine instead of phenylephrine being sicker at baseline which may account for the difference to a greater degree than is appreciated.
What about you? What is your practice regarding vasopressors in TBI? After reading this study and/or listening to the podcast episode, will you change your practice?