Case of the Month October 2025
What is Cushing’s Reflex?
One of the most frustrating scenarios that I face being a veterinarian is not being able to treat an animal. There are a variety of reasons:
Patient has untreatable condition (they are dying and cannot be saved)
The owner cannot afford treatment
The owner does not want to pursue treatment for “x, y or z” reason
I can’t treat the patient with the resources available
I don’t know how to treat the patient, the diagnosis is unknown
The patient is too aggressive for reasonable treatment
The owner doesn’t trust me, or trust the clinic, and takes the pet somewhere else
The owner does not have time to treat (leaving to go somewhere, deal with it later)
One patient that I can recall checked off more than one of these categories, and I wish I could have helped more when I had the chance.
“Frankie”, a 5 yo Spaniel
Frankie was brought in to triage on a gurney. She was crying in pain. Frankie woke up like this, and she was completely normal the night before.
On physical exam, Frankie was down on one side, unable to walk. She was intermittently howling, and it looked like she was in agonizing pain. She was alert, able to look at her surroundings, but made no effort to get up. Her heart sounds were normal, but the heart rate was slower than expected for an animal in pain. Her gum color was normal. She was not excessively drooling. Her head appeared normal, there were no signs of head trauma, and there was no blood anywhere on her body. Her eyes exhibited nystagmus (shifting side to side), and if you tried to lift her she seemed to favor a lean to the left. Her overall body condition seemed to be healthy, and her lymph nodes were normal. Her systolic blood pressure was 170. Her respiration was regular to moderately increased in rate, but with her crying in pain it was hard to assess.
Without having more information, the clinical signs fit a scenario called Cushing’s reflex.
The Cushing’s Reflex is a triad of clinical signs in a patient that has suffered a sudden increase of pressure inside the head (intracranial pressure). It indicates a grave prognosis if the patient has reached this point. The triad of signs are:
Increased blood pressure
Decreased heart rate
Irregular breathing pattern
Sudden increases in intracranial pressure might be from a tumor that has suddenly grown past a certain size causing a blockage or blood vessel rupture. It might be from hemorrhage inside the head from trauma or clotting disorder, or perhaps a genetic defect that has suddenly caused a rupture or fluid blockage.
In Frankie’s case, with no history of trauma, my number one suspect for her condition was a tumor but unfortunately, without an MRI available, diagnosis was not possible. Frankie was dying and suffering, so she was put to sleep.