by Syeda Maahin Mahmood, Pharm.D., PGY1 pharmacy resident, St. Joseph Mercy Hospital, Ann Arbor
Traumatic Brain Injury (TBI) is a serious health condition which contributes to almost one third of all injury-related deaths in the United States.1 TBI cases can range from mild to severe and cause a wide variety of short and long-term effects on cognition.2 TBI can also cause epilepsy and increase the risk of neurologic conditions such as Alzheimer's or Parkinson's disease.3 Because of the wide and lasting impact TBI can have, it is important to stay up-to-date on the management of this condition.
In September 2016, the Brain Trauma Foundation published updated guidelines on the management of TBI (previous guidelines were released in 2007).4 The updates to the guidelines included the addition of new sections such as decompressive craniectomy and cerebrospinal fluid drainage, limiting infection, and deep vein thrombosis (DVT) prophylaxis as it relates to concerns in TBI patients as well as adding more information regarding nutrition and the comparative effectiveness of different hyperosmolar agents. Pharmacists may have a variety of roles in managing patients with TBI. These include managing nutrition, optimizing DVT prophylaxis and recommending the use of appropriate pharmacologic therapy.
To start, monitoring labs in a TBI patient is similar to that of most critically ill patients with the goal of having electrolytes and glucose within normal limits. More specific to TBI, avoiding hyponatremia is especially important as this can lead to cerebral edema and increase intracranial pressure (ICP). Depending on the injury, TBI patients can also be at risk for hematomas or a hemorrhage, so decreasing the risk of bleeding is essential. This can be done by monitoring the complete blood count and targeting hemoglobin greater than 7 g/dL, platelets greater than 75 x 103/mm3 and an INR of less than 1.4.5
Furthermore, maintaining ICP at goal of 20 – 25 mmHg is another important component in the patient with a TBI. Monitoring ICP has been shown to significantly decrease mortality, especially in younger patients.6 Maintaining ICP at goal includes using both non-pharmacologic interventions, such as keeping the head of the bed at 30 degrees, decompressive craniectomy, or placement of an external ventricular device, as well as pharmacologic interventions such as choosing short-acting sedatives or the appropriate agents in hyperosmolar therapy.5,7 More severe cases of elevated ICP may require neuromuscular blockade or high anesthetic doses of propofol (if the patient responds to a bolus test dose of either agent respectively with successful lowering of ICP).5,7 Because of the possible risk associated with these interventions, an informed pharmacist is essential to the safety of these critically ill patients.
Pharmacists have an important role in optimizing seizure, DVT and infection prophylaxis for patients with TBI. Although the new guidelines discuss each of these topics, there is still a lack of definitive guidance. For seizure prophylaxis, the guidelines advise not using phenytoin or valproate for late post-traumatic seizures and recommend the use of phenytoin to decrease the incidence of early post-traumatic seizures depending on risk-benefit. Levetiracetam is another agent that is being used more often; however, more studies are needed to make evidence-based recommendations.4 For DVT prophylaxis, the guidelines report conflicting data evidence and simply state that low molecular weight heparin or low-dose unfractionated heparin may be used in combination with mechanical prophylaxis, but this may cause an increased risk for expansion of intracranial hemorrhage4. Therefore, the pharmacist can help inform the decision of when, or to even start, pharmacologic DVT prophylaxis based on a risk-benefit assessment thereby individualizing patient care.
Lastly, for infection prophylaxis, the guidelines no longer recommend peri-procedural antibiotics for intubation due to weak beneficial evidence and a lack of similar infectious disease policies, but recommend considering antimicrobial impregnated catheters to decrease catheter related infections.4 Pharmacists have an important role in infection prophylaxis and management through antimicrobial stewardship efforts.
Overall, the management of severe TBI patients is anything but simple. Pharmacists possess the capabilities and knowledge to help optimize and individualize pharmacologic therapy for these patients. With insight from the new guidelines, pharmacists can arm themselves with information and recommendations to make headway and improve the care of these patients.
References:
- National Center for Health Statistics. National Vital Statistics System. Centers for Disease Control and Prevention website. https://www.cdc.gov/nchs/nvss/. Updated Feb. 16, 2017. Accessed March 2017.
- National Center for Injury Prevention and Control. Traumatic Brain Injury & Concussion. Centers for Disease Control and Prevention website. https://www.cdc.gov/traumaticbraininjury/outcomes.html. Updated March 30, 2017. Accessed March 2017.
- National Institutes of Health. Traumatic Brain Injury: Hope Through Research. National Institutes of Neurological Disorders and Stroke website. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Hope-Through-Research/Traumatic-Brain-Injury-Hope-Through. Accessed March 2017.
- Carney N, Totten AM, O’Reilly C, Ullman JS, Hawryluk GW, Bell MJ, Bratton SL, Chesnut R, Harris OA, Kissoon N, Rubiano AM. Guidelines for the management of severe traumatic brain injury. Neurosurgery. 2016;80(1):6-5.
- American College of Surgeons. ACS TQIP Best Practice Guidelines. American College of Surgeons website. https://www.facs.org/quality-programs/trauma/tqip/best-practice. Accessed March 2017.
- Alali AS, Fowler RA, Mainprize TG, Scales DC, Kiss A, de Mestral C, Ray JG, Nathens AB. Intracranial pressure monitoring in severe traumatic brain injury: results from the American College of Surgeons Trauma Quality Improvement Program. J Neurotrauma.2013;30(20):1737-1746.
- Meyer MJ, Megyesi J, Meythaler J, Murie-Fernandez M, Aubut JA, Foley N, Salter K, Bayley M, Marshall S, Teasell R. Acute management of acquired brain injury part II: an evidence-based review of pharmacological interventions. Brain Injury. 2010;24(5):706-21.