Couple of Burn Questions

[slepyii]

Hey guys,

In our class we are getting conflicting answers on a couple of burn questions we had for a quiz. Our instructors are telling us there is more than one correct answer on the second question, though can't really explain why. We feel there should only be one answer. If you guys could look at the questions and give what you feel is the correct answer for each, and an explination as how you came up with that answer it would be great!

Q1. A 4-year-old female pulled a pot of boiling water from the stove. She has superficial and partial-thickness burns to her head and anterior trunk. What percentage of her body surface area has been burned?
a) 9%
b) 18%
c) 27%
d) 36%

They are telling us the answer to this one is D, and following the rule of 9's it makes sense as the head is 18% on an infant or child (doesn't specify age ranges in the book), and the anterior trunk would be 18%. Not sure where some got confused on this one after looking at the book, but said I would post it to get responses.

Q2. A 21-year-old male was working in an auto repair shop and sustained radiator burns to the anterior ascpect of both arms and to his anterior chest. According to the rule of nines, this patient has burns that cover ____ of his body surface area.
a) 18%
b) 27%
c) 36%
d) 45%

This one they are stating that they would accept either A or B, though according to the answer sheet they have it is A. This one is questionable as in our book (AAOS 9th Ed), it states the arms are 9% each, and the antior chest would give us another 18% for a total of 36%. This number didn't come up in class, as we figure antior arms would consist of 4.5% per arm for a total of 9% for both arms and 18% for the antior chest. This would give us a total of 27%, one of the answers they stated they would accept. The only way I can see them coming up with 18% as the correct answer would be to split the 'trunk' at the costal arch to give 9% for the chest and 9% for the abdomen, which would give us a grand total of 18% coverage for the burns.

The thing that confuses us the most on this question is that no where in the book (a whopping two sentences) does it state that we should be splitting sections of '9' into smaller portions to come up with a better estimate. It makes sense that you would, but some can't seem to see why as it says nothing in the book about it.

Any advice, or help you guys can give on these two questions would be greatly appreciated.

- Timothy

 

[MSDeltaFlt]

"The thing that confuses us the most on this question is that no where in the book (a whopping two sentences) does it state that we should be splitting sections of '9' into smaller portions to come up with a better estimate. It makes sense that you would, but some can't seem to see why as it says nothing in the book about it."

Not sure of the level class you are taking, but you just answered your own question.

Rule of 9's deals with percentage. Not an actual amount. One arm is 9%. The anterior arm is the front HALF. So, take half of 9. You get 4.5. As far as the anterior chest goes. Rule of 9's says that the adult front TORSO is 18%. So, the anterior CHEST is 9. Why they would accept two completely different answers to simple math is beyond me.

You only count 2nd degree burns and worse. UNLESS you're dealing with burns to the airway.

Not trying to be demeaning, but it is a common sense thing.

 

[slepyii]

Thanks Delta,

I'm not taking what you are stating as being mean. We are in an EMT-Basic class.

I shouldn't post messages when I am half sleeping, as I understand how the answers are acceived, but am trying to figure out a way I can explain it to the other students in the class, during our study sessions, that are having a hard time grasping the concept. The only other thing I can think of is to draw pictures for them and then shade in where the burns are located and have them figure it out that way.

If anyone has any other suggestions let me know, as I am trying to help others understand this simple concept of 'rapid guestimation' for the body surface area affected by the burns.

One question that I do have is how far would you split sections to get better estimates, say if it was just the antior portion of the upper arm would you split 4.5% to get 2.25%, or would you switch to using the rule of palms (~1% for area size of patients palm)?

Thanks,

- Timothy

 

[Meursault]

You could just use my approach for dealing with the other students in your class: assume they're a combination of gunners and people deficient in common sense. The gunners challenge test questions because they want the maximum grade for the least amount of work, not because they aren't getting it. The others are frequently refractory to peer tutoring and what seem to be clear explanations. I remember questions like this from my class, where somewhere around 85% of people failed the first Rule of Nines quiz and then whined about it.

As far as the rule of palms, I don't think anyone's going to require decimal percentages of TBSA. Round to the nearest 1%. Most of the test questions I've seen are structured so that you don't need to do that.

 

[MSDeltaFlt]

Tim,

For prehospital situations, the rule of 9's is sufficient. There's no need to worry about 2.25%. That's for the burn centers, not EMS. Your drawing on a picture sounds like that will work.

Good Luck