Many of us grew up in the age of EMS, which emphasized the need to memorize everything. You can never use a calculator; if you do not know the answer before someone thinks of the question, you will be labeled an idiot. The reality is, nothing could be farther from the truth!
Are there things we need to commit to memory and know off-hand? Absolutely! But this would be an impossible expectation, especially in the environment in which we practice medicine.
The current era encourages the inquisitiveness of all parties (patients included) and values the ability to utilize resources when system two thinking is required. This blog is an example of exactly that.
On a chilly Sunday morning, my partner and I were dispatched to a private residence in our community to care for a 2-year-old female with an altered mental status. While enroute to the scene, dispatch notified us that the patient suffered from “PDCD”, and the patient’s parents are requesting transport to the local children’s hospital.
My partner asked if I was familiar with “PDCD.” Having no clue, I googled the disease from my phone and discovered that “PDCD” is the acronym for “Pyruvate Dehydrogenase Complex Deficiency.” But what does this mean? We are going to be there soon!
Ok, imagine reading this a few minutes before the call:
"The Pyruvate Dehydrogenase Complex (PDC) metabolically converts pyruvate into acetyl-coenzyme A (ACoA) via glycolysis, which is the first step of the Krebs, or Citric Acid, Cycle. The Krebs Cycle converts carbohydrate, fatty acid, and amino acid substrates into cellular energy within the mitochondria.”
"When a patient suffers from PDCD, pyruvate cannot be converted into ACoA, thus limiting substrate availability for completing the Krebs Cycle. This lack of substrate availability results in decreased mitochondrial energy, which causes acidosis, acidemia, and other neurological dysfunctions due to increased lactic acid production.
Before birth, the lack of mitochondrial energy results in the fetus suffering from brain malformation. Post-birth, however, the neonate may suffer from progressive neurodegeneration, including hypomyelination, cystic lesions, cerebellar gliosis with gray matter degeneration, and necrotizing encephalopathy."
So basically, my brain said:
"This disease reduces the amount of ATP available." We all know that ATP is cellular energy, so I expect to see a super lethargic kid. I also know that if pyruvate can't enter the mitochondria, it gets converted by the liver to lactate. This means the kid probably lives in an acidotic state.
Upon arrival at the scene, the patient’s mother greeted my EMT partner and I at the front door and escorted us to the living room, where the patient was found supine on the couch, being tended to by her father. The patient was conscious and sluggishly followed us with her eyes but was otherwise somnolent.
My brain is like, "ok! This makes sense!"
The patient’s mother informed us that the patient suffers from PDCD and is generally non-verbal but interactive with limited motor function. The patient had poor feeding throughout the last 24 hours and became more somnolent and less interactive. She reported the patient having increased shortness of breath, which appeared “irregular.” On the morning of this day, the patient had a tonic-clonic seizure, lasting approximately one minute, which prompted the contacting of 911 after the seizure stopped.
During my assessment, I observed an approximate 12kg, well-cared-for but underdeveloped female patient with no outward evidence of traumatic injury. The patient’s head revealed frontal bossing (yes, a new term to me), a wide nasal bridge, and anteverted nostrils.
I clearly remember the patient breathing in an ataxic pattern, around 44 breaths per minute. The patient’s diaper was dry, and the patient’s mother reported no bowel movements in over 24 hours and decreased urinary output over the last 12 hours.
The patient’s heart rate was 140 beats per minute, regular, with no ectopy. However, I did observe electrical alternans. The patient’s blood pressure was 74/46, and her SPO2 was 90%, with an ETCO2 of 17mmHg. Point-of-care testing revealed a serum glucose level of 71mg/dl and a serum lactate of 3.5mml/L.
Immediately, it was recognized that the patient was critically ill, and my partner and I opted to stabilize the patient before initiating transport. Due to the patient’s probable acidemia, bag valve mask ventilation was initiated with 5cmH2O of PEEP and a nasopharyngeal airway.
My partner and I established intravenous access, and the patient received a 20ml/kg bolus of lactated ringers using a push-pull method with a 3-way stopcock.
A reassessment of the patient following initial interventions revealed a blood pressure of 80/P, a heart rate of 128 beats per minute, an SPO2 of 96%, an ETCO2 of 28mmHg, and a respiratory rate of 34 breaths per minute. The patient continued to breathe rapidly beneath the BVM ventilation we were providing.
The patient’s mother accompanied me in the patient compartment of the ambulance on our 30-minute ride to the children's hospital.
While transporting to the emergency department, the patient’s mother informed me that PDCD affects less than 1 in 50,000 individuals and is more common in males than females. She explains that 1 in 3 cases result from recessive carriers, as in the case of her daughter; however, most commonly, PDCD results from the mutation of the X-Linked E1 alpha enzyme.
As with most critically ill children, the patient’s mother proved to be an asset in learning about the patient’s specific disease pathology and care thereof. In the case of PDCD, the patient’s mother reported that the standard of care is cofactor supplementation with Thiamine, Canitine, and Lipoid Acid administration to prevent worsening pathophysiology and provide an alternate means of mitochondrial energy supply.
After learning this, medical control is consulted for additional treatment recommendations. During the consultation, the physician medical director advised that she had no additional orders or direction at the present time, as the EMS care for PDCD is largely supportive.
Since the patient’s vital signs and mental status were trending in the right direction following oxygenation, ventilation, and volume administration, the medical director advised that sometimes “less is more” in these situations, as treating the symptoms of acidemia is not a supplement for treating the underlying cause. However, the consulting medical director did recommend more aggressive BVM ventilation and a bolus administration of Sodium Bicarbonate at 1mEq/kg should the patient’s condition worsen (of course, lol).
Upon arrival in the pediatric emergency department, the patient was conscious and alert to her normal mental status, which included being nonverbal. However, the patient became more interactive and no longer tolerated BVM ventilation or nasopharyngeal airway placement.
The patient’s heart rate was 116 beats per minute, her blood pressure was 84/62 mmHg, SPO2 was 99%, and ETCO2 was 34mmHg with a respiratory rate of 20 breaths per minute with improved tidal volumes and patterning.
As care was transferred to the emergency department staff, the patient’s mother thanked us for our kind and compassionate care and sent us on our way. In the hall, my partner said, “Wow, we really faked that one; good job!”
The mindsets of “fake it ‘till you make it” and “always make it look like you know what you are doing” are great when it comes to EMS TV shows, but in reality, they can be dangerous.
There is no shame in saying, "I have no idea what GBSGSN Syndrome is?" You should never feel bad for saying, "I have not transported a patient on this device in years, and I would love a refresher!" In fact, when a clinician admits to not knowing something, it drives further confidence in the things they do know.
This case of PDCD is undoubtedly rare, but having a random disease process thrown to you in the heat of the moment is something we all have encountered. Maybe it’s a disease process like PDCD, or perhaps it is a medication on the list that is unfamiliar to them. Regardless of the circumstance, you will encounter scenarios where you do not have a clear mental model for the workflow and treatment.
Nobody would ever expect you to walk into someone else's kitchen and know exactly where everything is. Similarly, nobody would expect you to hear about a random rare disease and magically know the treatment.
In his new book, Clinical Airway Management, Austin Kiser writes, “Our individual clinical expertise has nothing to do with our organization. It has everything to do with who we are as clinicians.” Nothing could be more accurate! Our job and responsibility as professionals is to invest our time, money, and interests to advance our clinical knowledge and expertise. Our professional development is our responsibility!
Does the culture of our organization sometimes play a role in this? Certainly. Employment at an organization with a learning culture makes you more likely to value learning and development.
Unfortunately, the opposite is also true. With this in mind, it is important that we surround ourselves with those who build us up and want to see us succeed in our quest for knowledge and advancement. It is also important that these same individuals value the effort being put forth to ensure our patient's safety, and sometimes, this means looking it up!
My father, an emergency physician, gifted me a medical dictionary when I enrolled in EMT school. In it, he wrote:
Always remember what you have learned from these books. Remember that it is not important to know every word in a book; it is less important that you act as if you do. Think about the man who wrote the book, bound it, and sold it. Without them, no book, knowledge, or modern medicine would exist.
Knowledge is power. Never stop looking for it. Always ask the question. Always use the checklist. Always look it up!
The patient will thank you for it; we are only human.
References
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