Managing head trauma in veterinary patients
Veterinary patients presenting with head trauma can be intimidating but can improve immensely with intravenous fluid therapy, supplemental oxygen, and nursing care.
Head trauma in veterinary patients is an emergency presentation that commonly occurs after a motor vehicle accident or other blunt or penetrating trauma. There are several unique considerations for patients that have sustained head trauma at presentation and during their hospital stay. During a session at the Fetch dvm360® Kansas City conference, Danielle Powers, DVM, DACVIM (Neurology), of the Animal Medical and Surgical Center in Scottsdale, Arizona discussed management of head trauma for veterinary patients from initial presentation through recovery.
Triage and history
Patients presenting with head trauma should be triaged like any emergency patient. Airway, breathing, and circulatory status should be stabilized while minimizing movement of the patient. Powers reminds clinicians that many of these patients present in shock, and their mentation may improve significantly with the treatment of shock alone.
Ideally the neurological evaluation should be performed prior to administration of medication. Clinicians should assess the pupillary light reflex (PLR), pupil symmetry, ambulatory status, and mentation status of the patient. Use of the Modified Glasgow Coma Score (MGCS) can provide a quantitative evaluation that allows for objective reassessment overtime.
In addition to asking about comorbidities and medications, history taking should include specific questions to assess when the trauma occurred and assess for any loss of consciousness, mentation, and seizure activity following the trauma.
It is essential when handling head trauma patients to minimize stress and prevent the patient from struggling; however, sedation and general anesthesia are contraindicated in most head trauma cases. Administration of a pure mu opioid can help to address pain and facilitate handling when obtaining diagnostics.
A complete blood count (CBC), serum biochemical profile, and urinalysis should be assessed in these patients. Jugular venipuncture should be avoided when collecting samples as compression of this vein can increase intracranial pressure. Noninvasive blood pressure, preferably with a Doppler, blood gas analysis, and imaging needed to assess other wounds (such as chest radiographs and ultrasonography) should also be performed.
MRI is the imaging modality of choice for brain imaging, but unless the patient is declining, general anesthesia should be avoided. If imagining is deemed necessary, the patient should be cardiovascularly stabilized prior to anesthesia. CT scans are the preferred imaging modality for assessment of skull fractures as radiographs are difficult to interpret and may be inconclusive.
Treatment goals for head trauma patients will vary by the patients’ status at presentation and comorbidities. Basic stabilization measures, including placement of a large gauge IV catheter, delivery of intravenous fluids, and supplemental oxygen delivery can improve mentation status significantly in some patients. Pain control is also essential for head trauma patients and pure mu opioids are recommended as they can be easily reversed in the case of declining neurologic or cardiovascular status.
More specific treatment goals include seizure management, controlling increased intracranial pressure, maintaining carbon dioxide levels, and maintaining cerebral perfusion pressure. Powers reminds veterinarians that “by preventing the hypovolemia and hypoxemia secondary to shock, often the brain function will improve without necessarily treating the brain trauma directly.”
Administration of steroids is no longer recommended as a first-line therapy as there is limited clinical evidence in human medicine to support their use. Additional treatments including controlled hypothermia and administration of other medications have been discussed in the literature, but results are currently equivocal. Powers feels that “these may or may not be helpful and are clinician’s preference when [used] as a treatment for head injury.”
In most cases, giving time for the patient to recover is a core part of treatment. During recovery, nursing care is essential to prevent secondary problems such as pressure sores, aspiration pneumonia, urine retention, and corneal ulceration. Oral medications, food, and water should be withheld until the patient is able to swallow on their own.
Prognosis and Recovery
The prognosis for head trauma patients is variable depending on the severity of the injury and comorbidities. Both primary and secondary brain injuries occur as a result of head trauma, resulting in immediate and delayed effects. The MGCS can predict prognosis, with lower scores carrying a poorer prognosis. In human medicine, Powers shared that prognosis is “significantly correlated with the level of oxygenation and systolic blood pressure prior to and during medical intervention.”
Powers notes that while recovery can be variable, for pets “the degree of recovery may be less important if they can perform tasks required as a companion animal, as opposed to a working animal or person.” Quality of life, comfort, and ability to do basic tasks such as eating, drinking, and walking are the most important considerations for companion animals recovering from head trauma.
Owners of pets who have experienced head trauma should be advised that seizure activity can occur up to four years after the brain injury, but the longer a patient goes without seizures, the less likely they are to develop.
Take Home Points
Head trauma is an emergency in veterinary patients. After rapid evaluation, pain medication, gentle handling, IV fluid support, and supplemental oxygen are the most critical things the veterinary team can provide to help facilitate recovery. More specific interventions are available and will vary depending on the degree of the injury.
Dr Boatright, a 2013 graduate of the University of Pennsylvania, is a practicing veterinarian and freelance speaker and author in western Pennsylvania. She is passionate about mentorship, education, and addressing common sources of stress for veterinary teams and recent graduates. Outside of clinical practice, Dr. Boatright is actively involved in organized veterinary medicine at the local, state, and national levels.