Your Captain Speaking: How to Make a Checklist Work

In the EMS and medical communities, we seemingly have thousands of mnemonics to help us do our jobs. We all have our favorites and use them regularly. For many of us, before we renew ACLS or ITLS, we make sure we can recite the respective mnemonics. The “5 H’s and 5 T’s” for ACLS are valid and truly critical points to help remember the possible reversible causes of a patient in cardiac arrest (see sidebar). Likewise, in ITLS there have been variations over the years of an acronym, DCAP BTLS, that’s a must-know for the course and reality. How about a SAMPLE or OPQRST acronym? Do you fill out your patient reports using the SOAP format?

These and others were standard for me and a majority of those in EMS. However, there is a dark side to these mnemonics and acronyms. After you finish reading this article, you may be a little uncomfortable and wish for a better way. 

Training Scars

Tracey Loscar’s January Midlife Medic column in EMS World, “Making a List and Checking It Twice,” made me reconsider my own long-established habits with these mnemonics—specifically performing critical items by memory and “training scars.”

An example I’ll use is a real-world cardiac arrest: We need to consider the reason(s) the patient does not have a heartbeat. Can we fix the problem and restore circulation? The pressure is on. The clock will not stop or slow for us. Our adrenaline is amped up. The situation is stressful to say the least. There is a widely used mnemonic in ACLS commonly referred to as the “5 H’s and 5 T’s,” and it’s been my friend for many years. There I’ll be, trying to recall it by memory and maybe doing compressions at the same time. 

There have been numerous studies on human memory that tested recall under normal conditions, fatigue, stress, and by the time since the specific memory was last used. Here’s the short version: Human memory is flawed. Some people are better than others at recall, but a fair-minded person will acknowledge that their ability to recall a specific list of items will ebb and flow during a day and over time. Make the list longer than 5–7 items, and recall performance plummets. 

Training scar—I’ll use this phrase to mean that you practice a specific event in a certain way, but when the real event occurs, it doesn’t unfold as you practiced, yet you follow the same habit you established in training. For example, you’re being tested on a cardiac arrest protocol, and on the fourth H you identify the problem of acidosis (too many hydrogen ions) and initiate the correct intervention. OK, this is good! 

But what did not happen in this example is that you did not continue through the rest of the mnemonic to determine if there were additional areas that also needed attention. Patients often have more than one thing going wrong at the same time. It would be a training scar not to continue through the entire list of H’s and T’s from beginning to end.

Here’s where these two problems, flawed memory and training scars, intersect, and a possible solution: the checklist. A properly written checklist will set you in the right direction and list items you need to consider. If the first item on the checklist is the H of hypoglycemia and blood sugar is indeed low, you can follow a treatment path. Here’s the major point: You don’t stop there. You continue to review all the possibilities. 

Airline pilots know what to do if they’re interrupted in the middle of a checklist. They are drilled and drilled to always finish the checklist. They announce the title as they begin it and repeat it when it’s complete, plus the word complete at the end: “Engine fire checklist complete.” This ensures you are on the correct checklist from start to finish. If you are interrupted while performing the checklist, you start it all over from the beginning, never from where you thought you left off.

In our EMS example, you should not stop at hypoglycemia but also consider hypovolemia and hypoxia, which might also be significant problems. Neither would you ignore the “5 T’s.” So the solution would seem to be, obviously, to make up a checklist and hand it out to everyone, right? 

Nope, that is guaranteed to fail in a spectacular fashion. Checklists must be trained on, and one size does not fit all. Checklists are most commonly done as a challenge and response between two people, not just one person in isolation. 

An exceedingly simple but important checklist for an airplane is the landing checklist. There are only three items on the Boeing 747’s: speedbrakes, landing gear, and flaps. I’ve literally run this checklist thousands of times, yet each time it was called for, we pulled out the checklist, the pilot monitoring read each item aloud, the pilot flying responded, and only then did we move on to the next item. Finally, “landing checklist complete” was announced when we were done. 

What if we were interrupted by a radio call after we started the checklist? Two choices: One is to ignore the radio call and finish the checklist, then answer the radio. This annoys the facility calling you, but hopefully they’ll get over it. Your second choice is to answer the radio call, then restart the landing checklist from the beginning. 

What if I point to the landing gear handle and give a thumbs-up sign? Not acceptable. I look at the position of the handle and check that the words on the indicator message are correct, then I can verbally say “down.” No pointing, no hand signals.

A medical checklist, any checklist, needs to be handled in the same manner. You have to be trained first. Checklist discipline means something. Interruption management is important. Everyone does it the same way. You recognize you need a checklist, and then you run the correct checklist. Complete all its steps. I’m not disrespecting ACLS or ITLS or their protocols; quite the opposite—that minor slice of ACLS represented by the “5 H’s and 5 T’s” was just an example. ITLS (BTLS before that) students have for many years used variations of the DCAP BTLS acronym (for deformities, contusions, abrasions, punctures/penetrations, burns, tenderness, lacerations, swelling). The same argument can be made that it can be tough to remember and fully complete.

In her article Loscar wrote:

We are a field that speaks in acronyms and is driven by algorithms. At some point in our early evolution, our culture decided that rote memorization could somehow make up for the dearth of didactic knowledge we were sent into the trenches with.

Here’s the takeaway: Memory devices and acronyms can be very helpful, but we are human. We have problems with recall during stressful events. There is no such thing as a one-size-fits-all checklist or universal checklist for aviation or EMS. Checklists require training and discipline. They can be very difficult to write and evolve over time. If the next time you’re on scene running a mnemonic and are uncomfortable doing it by memory and wish you had a checklist instead, then perhaps we are indeed evolving.

Captain Dick Blanchet (ret.), BS, MBA, has worked as a paramedic for Abbott EMS in St. Louis, Mo., and Illinois for more than 20 years. He is also an airline captain on a Boeing 747 with more than 21,000 flight hours. 

Sidebar: The 5 H’s and 5 T’s

The 5 H’s and 5 T’s represent a mnemonic (memory device) for possible reversible causes of cardiac arrest. It is a well-established, reasonable list to consider and not likely to change much over time. 

5 H’s

• Hypovolemia
• Hypoxia    
• Hydrogen ions (acidosis)
• Hyper-/hypokalemia
• Hypothermia

5 T’s

• Cardiac tamponade
• Tension pneumothorax    
• Thrombosis (myocardial infarction)
• Thromboembolism
• Toxins