Welcome to PICU Doc On Call, A Podcast Dedicated to Current and Aspiring Intensivists. I'm Pradip Kamat and I'm Rahul Damania. We are coming to you from Children's Healthcare of Atlanta - Emory University School of Medicine.
Welcome to our Episode with a 15 year old Male having hypotension and bradycardia.
Here's the case presented by Rahul:
A 15 year old M presents to the PICU after sustaining an acute trauma. The patient was brought to the ER by his family after being on a boat and lifting a heavy object. He did not fall, sustain any head or extremity trauma, but did feel an achy non-radiating back pain shortly after the event. His grandmother states that the patient kept complaining about the back-pain and over the next few hours the patient became increasingly fatigued and flushed in the face. The patient was able to move his arms and legs and still walk, however family became concerned when the patient had abdominal fullness and was unable to urinate properly. He presents to the emergency department for further evaluation. In the emergency department he is noted to be awake however intermittently sleepy. His vital signs are notable for a HR of 58 bpm and a blood pressure of 85/60. He has 3/5 motor strength in his lower extremities with decreased sensation in his feet. Patellar reflexes are 1+ bilaterally. Rectal tone is normal. Acute resuscitation is begun for this patient.
To summarize key elements from this case, this patient has:
This is a great summary of key history findings for patients who present with hypotension and bradycardia as it relates to spinal cord issues. Remember that patients who have Down's syndrome may have a predilection to have lax ligaments especially in the upper verterbrae. As a result, you should have an increased index of suspicion if a Down's Syndrome patient presents with hypotension and bradycardia in the presence or absence of trauma. In a study published in 2017 in Neurocrit Care it was estimated that about 20% of patients with Trisomy 21 may have atlantoaxial instability.
A great point which you just highlighted. Remember that when you approach hypotension and bradycardia, it is also important to focus on cardiac etiologies:
Bradycardia directly pulls down the cardiac output, potentially causing shock, and especially if you have a blunted vasoconstrictor response you can couple this bradycardia with hypotension.I do not want to delve too much out of the scope of today's episode but there is a wide differential for bradycardia but specifically related to history you should consider intoxication as a cause of bradycardia and hypotension.
Going back to our case, are there some red-flag symptoms or physical exam components which you could highlight when you approach?
Yes, in this patient who we suspect spinal cord injury, we would like to perform a comprehensive neurological exam:
On physical exam, this patient had a flushed face, and this could be related to an Interruption of sympathetic chain causing a horner's syndrome like presentation.
Recall that Horner's Syndrome is a triad of ptosis, miosis, and anhidrosis which can present as facial flushing.
During this spinal cord assessment it is important to perform a rectal exam to check for perianal sensation and rectal tone
Other physical exam components includes assessing for priapism in male patients. Priapism in male patients may be present from abrupt loss of sympathetic tone to pelvic vasculature, causing a high-flow arterial priapism.
This is a great review of history & physical components for hypotension and bradycardia as a presentation of spinal cord injury — I think the key point here is to remember that this presentation is related to a loss of sympathetics and thus unopposed vagal tone which leads to the acute symptamology of Distributive shock with hypotension and bradycardia
To continue with our case, the patients labs were consistent with:
I would also like listeners to note that in patient with high cervical spinal cord injuries, the presence of hypercarbia suggesting hypoventilation may prompt for the need for early intubation
What did the imaging show in this patient?
Interesting this may have been related to his boat trauma. Remember listeners, that CT is very sensitive for defining bone fractures in the spine. Because CT is more sensitive than plain films, patients who are suspected to have a spinal injury and have normal plain films should also undergo CT. CT also has advantages over plain films in assessing the patency of the spinal canal. CT also provides some assessment of the paravertebral soft tissues and perhaps of the spinal cord as well, but is inferior in that regard to MRI.
OK, to summarize, we have:
The correct answer is D. alpha-1 receptors. Remember that patients with neurogenic shock are devoid of sympathetics. Thus, you want to initiate sympathomimetics early. Some patients may require continuous infusion of norepinephrine, phyenlephrine, or dopamine.
As you think about our case, what would be your differential?
Pradip, what about cauda eqina syndrome?
Great question. So the Cauda equina is the lumbar and sacral roots caudal from the conus medullaris. These patients are going to have multiple nerves affected and may also have progressive incontinence.
In fact, studies have shown that Finding of urinary retention (post void residual > 100-200 mL) has 90% sensitivity for cauda equina syndrome.
A key distinction between the two is that cauda equaina syndrome in general has an asymmetric weakness with primarily LMN signs. These patient are going to have urinary retention that presents later from the onset of injury.
OK, to summarize, Conus medullaris syndrome you damage spinal cord, think early onset issues of bowel and bladder with UMN vs CE syndrome you have more damage of peripheral nerve roots and you in general will have a progressive inconitence with UMN signs.
RAHUL, I have also heard of this acronym, SCIWORA. What is this clinical entity?
SCIWORA stands for Spinal Cord Injury WithOut Radiographic Abnormality (SCIWORA)
In the pediatric population this differential is greater concern in pediatric population due to laxity of ligaments and weaker muscles
In this disorder, there is No discernible fracture on conventional films or computed tomography scans however patients may have spinal cord injury or on exam neurological deficits. The Mechanism is transient subluxation, stretching, or vascular compromise.
Finally, let's contrast neurogenic shock with spinal shock — this is a subtle distinction clinically but has been described in the literature Rahul can you shed some light on that?
If our history, physical, and diagnostic investigation led us to neurogenic shock related to acute traumatic spinal cord injury as our diagnosis, what would be your general management of framework?
What about steroid use in spinal cord injuries?
In terms of prognosis:
This is a great time for us to highlight the multi-disciplinary effort that goes into caring for these children. It is important in the acute setting to work closely with neurosurgery, ortho, neurology, and the critical care team and further in the subacute setting involving the rehabilitation team.
This concludes our episode on Neurogenic shock. We hope you found value in our short, case-based podcast. We welcome you to share your feedback, subscribe & place a review on our podcast! Please visit our website picudoconcall.org which showcases our episodes as well as our Doc on Call management cards. PICU Doc on Call is hosted by myself Pradip Kamat and my cohost Dr. Rahul Damania. Stay tuned for our next episode! Thank you!
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