Updated May 11, 2015
How is it that some EMS practitioners seem to just know what’s wrong with their patient and begin treatment in less than a minute? If you think it’s about experience, you’re right. How long does it take for a recently certified “entry level competent” provider to get enough experience to be able to do the job like a veteran?
By using critical thinking skills and applying recognition primed decision making theory, we can work to shorten the journey. Whatever your role in EMS — whether you’re a student, new graduate, experienced provider, preceptor or instructor — you can use these concepts and principles and apply them to improving your own or your students’ practice.
This approach grew from experiences I had back in the early 1990s. I was precepting a student who we’ll call Mike. He was a nice guy who really wanted to be a paramedic. Unfortunately he was struggling with his assessments. He seemed to be all over the place with his interview and physical exam. He didn’t know what questions to ask and had trouble using the interview and physical exam findings that he was able to acquire to come to a diagnosis. He seemed disjointed and confused. After several unsuccessful counseling sessions, I had a long talk with Mike and explained that unless he improved rapidly and dramatically, he was going to fail his field clinical.
What follows is the method that Mike and I worked out, how he got himself on track, passed his field clinical, and eventually became a successful full-time paramedic in a busy urban system.
Setting a foundation
We started by looking at the universe of medical complaints and looked for a way to organize his approach to assessments. Starting at the head, we identified altered mental status as a major set of presentations and complaints. Moving to airway and breathing considerations, we identified difficulty breathing and shortness of breath as the second set. Finally, considering circulation, we identified chest pain. In general, patients with complaints in these three basic sets of presentations — altered mental status, dyspnea/SOB, and chest pain — are the most critical for EMS practitioners to diagnose and treat. This generalization formed the basis for a process and a structure that helped Mike to organize his approach to patient assessment. We created a broad and deep knowledge base upon which Mike built his physical exams and interviews. This became his cognitive foundation for building his clinical judgment.
We began by identifying all of the causes of altered mental status. Mike wrote out a comprehensive list of all of the causes of that he could consider. Then he referred back to his texts and talked with other students as well as other medics to expand his list. It’s a long list and it took several days to get it completed; the deeper you go into the pathophysiology, the longer the list gets.
How many causes of altered mental status can you list right now? Once you complete your list, ask your coworkers and see what they can add. Go back to your paramedic text and add some more. I’m sure you can find lots more using the internet. I just Googled “causes of altered mental status” and in 0.25 seconds I got over 300,000 hits; there are some great resources listed in the first ten hits.
Tackling differential diagnoses
Once Mike had developed a comprehensive list of causes of altered mental status, the next step was to write out all of the signs and symptoms of each cause. What Mike found was that there was overlap in the signs and symptoms and, more importantly, that some findings were specific to particular causes. He also found that some causes had particular groups of typical signs and symptoms. Once he had all of the signs and symptoms identified, he highlighted the detailed findings that differentiated one cause from others. This became his starting point for differential diagnosis.
We talked about his list and began to use it to identify questions Mike could use in his interviews to help him zero in on a diagnosis. His list also helped him organize his physical exam; there were particular things he was looking for related to the lists of signs and symptoms he had created for all of the diagnoses of altered mental status. Finally, we linked each diagnosis with treatment following the appropriate protocol.
Whenever we had an altered mental status case, we would review his interview and physical exam and his findings. We keyed in on the details of the patient’s presentation. What did the patient look like? How did the patient sound? What did the patient feel like? We also looked back to determine how the patient talked, how the patient moved, and fixed the images, linking them to the diagnosis. This reflective activity is a major component of critical thinking. We continued to build a set of altered mental status “patient presentation files.” The conscious creating of these mental images and detailed findings files prepared Mike for decision making under time pressure and uncertain circumstances. He was better prepared to use what Gary Klein calls Recognition Primed Decision Making in Sources of Power: How People Make Decisions (1998).
Refining the methods
As Mike continued to refine his approach to altered mental status, we moved on to the next phase: difficulty breathing. We followed the same sequence: make a comprehensive list of the causes of dyspnea/SOB, list the signs and symptoms of each cause, set up a series of key questions and physical exam findings that would lead to a specific diagnosis. Link each diagnosis with the correct treatment protocol. When he had dyspnea completely mapped out, we moved on to chest pains, and followed the entire sequence one more time.
The last piece of the puzzle was incorporating trauma. Trauma is much simpler than medical complaints. The bottom line in trauma assessment and treatment is to find the injuries, stabilize and transport. A patient who suffers serious multi-systems trauma generally needs rapid surgical intervention. Stabilization will usually include full spinal immobilization. The use of tourniquets has reentered the arena for controlling severe bleeding. Because uncontrolled arterial bleeding can lead rapidly to death, using a tourniquet to prevent exsanguination has been moved up in some treatment protocols to occur before airway and breathing. Some protocols also now include the use of haemostatic agents. The doctrine of permissive hypotension has gained favor. Check your local protocols to determine the appropriate treatment. Rapid transport to a trauma center completes the picture.
If the trauma is minor, the course of action is still assess, stabilize, and transport. Assess for pulses and for motor and sensory function distal to the injury. You may have to realign an angulated injury to restore lost pulses. Stabilization will be completed by splinting. Reassess for pulse, motor and sensory function after splinting. Finally, advanced practitioners may administer pain medication. All of this is completed quickly and the patient transported for definitive care.
By the end of the process, Mike had the whole thing written out on several pieces of poster board that he had taped together. We called it the Medical Emergency and Trauma Assessment Algorithm or META Algorithm. For Mike, it established a broad and deep cognitive foundation for his practice.
Reaping the benefits
The value of developing the META Algorithm is the process of working your way through it. The point of the process is manifold. First, it makes you examine the entire patient assessment process from the perspective of all the possible diagnoses and their presentations. Second, it provides structure to organize your approach to your interview and to your physical exam by making you consider the data points and what findings you expect that are associated with various diagnoses. Third, it helps to structure the reflective process during case review. Finally, you begin to purposely develop a set of mental “patient presentation files” related to each diagnosis that will help you to recognize and diagnose similar cases in the future. Using this technique helps to speed up the acquisition of information by requiring that you attend to the details before a case, during the case, and then again after the case.
Building your own cognitive foundation for clinical judgment is simple. By that I mean that the method is simple. However, it takes time and effort; the payoff on the investment is worth the work. If you’re a preceptor or instructor, you can share this technique with your students and your students will benefit.
If you follow the same sequences that Mike used back in the early 1990s, you will be building your own support framework for the differential diagnosis of medical complaints. You will be prepared to assess, stabilize and rapidly transport trauma patients. You will be beginning the process of creating or refining a set of personal “patient presentation files” that will help you make decisions when you see similar presentations in the future. You can continue to refine your files throughout your career.
