Trauma Tuesdays! The Burn Patient: Rule of 9s and The Parkland Formula

 ·   · 

A 45 year old male comes into the resuscitation bay after being found in a house fire.  His arms and chest have a leathery gray appearance with patchy red areas and blistering.  You recall that burn patients need large volume fluid resuscitations…  

How do we calculate the TBSA (total body surface area) affected?

 

Rule of 9s!

For adults:

Head = 9%

Front Torso = 18%

Back Torso = 18%

Left Upper Extremity = 9%

Right Upper Extremity 9%

Left Lower Extremity = 18%

Right Lower Extremity = 18%

Perineum = 1%

(18 x 4) + (9 x 3) + 1 = 100%

*Does anybody else do this additional calculation every time they use the rule of 9s to make sure they get 100% of the body?*

 

Note that for children, the surface area of their head comprises a larger percentage of body surface area when compared to an adult, so the rule of 9s needs to be adjusted.

 

Remember: do NOT include first degree burns in TBSA percentage calculations.

 

Now what?  Calculate the estimate volume of fluid resuscitation required for a burn patient in the next 24 hours with The Parkland Formula = 4 mL x %TBSA x weight (kg). 

**Use the % TBSA and not a fraction, e.g. 4mL x 36% x 70kg = 10,080 mL**

 

Plug in those numbers!  Also available at https://www.mdcalc.com/parkland-formula-burns

 

Give the first half of the total volume calculated in the first 8 hours and the remaining volume over the following 16 hours.

 

This is an estimation of the volume of fluid resuscitation, so titrate the volume of resuscitation with patient response! Goal is to keep urine output at 0.5mL/kg/hr for adults and 0.5-1mL/kg/hr for children <30kg.

 

Check out this amazing pdf: http://ameriburn.org/wp-content/uploads/2017/05/burncenterreferralcriteria.pdf

 

 

Want to read more?

http://www.emdocs.net/modern-day-burn-resuscitation-moving-beyond-parkland-formula/

https://www.uptodate.com/contents/emergency-care-of-moderate-and-severe-thermal-burns-in-adults

 

 · 

Tumor Lysis Syndrome (TLS)

 ·   · 

Who gets it?Patients with lymphoproliferative or hematopoietic malignancy, and sometimes those with a large tumor burden. Chief complaint is vague, with weakness, anorexia, nausea, vomiting, diarrhea, seizures, and arrhythmias.

What is it? An oncologic emergency during antitumor treatment (and may also occur spontaneously).

Where do I look? Complete metabolic panel (including phosphorus, calcium, LDH, and uric acid) and EKG.

When would this happen? Anytime, including 3 days prior to or up to 7 days after initiation of chemotherapy.

Why does this happen? Lysis of malignant cells causes a massive release of intracellular material into circulation, resulting in metabolic derangements: Hyperuricemia – nucleic acids break down and become uric acid Hyperkalemia – high intracellular potassium content Hyperphosphatemia – high intracellular phosphate content HYPOcalcemia – excess phosphate binds to serum calcium, making calcium phosphate

And then what happens? Acute kidney injury from uric acid and calcium phosphate crystal deposition. Arrhythmias and neurological manifestations of electrolyte disturbances.

How is TLS treated? - IVF hydration - Management of hyperkalemia and symptomatic hypocalcemia - Allopurinol to decrease uric acid production - Rasburicase to decrease uric acid levels - Consult nephrology and oncology, consider renal replacement therapy and phosphate binders

Want to read more? http://www.emdocs.net/9077-2/ https://www.ebmedicine.net/topics.php?paction=showTopicSeg&topic_id=216&seg_id=4349 https://lifeinthefastlane.com/ccc/tumour-lysis-syndrome/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4806807/

 · 

Topical Tetracaine: To Take Home or Not?

 ·   · 
Hi everyone,
For today's POTD, we will be looking at the question of whether tetracaine and other topical anesthetics are safe to give patients to take home for corneal abrasions.
Conventional teaching is that while effective at reducing pain, prolonged use of topical anesthetics leads to poor wound healing of the corneal epithelium, and potential development of badness such as corneal ulcers down the line.
Where does that dogma actually come from, and does that really mean your patient's eyeball is going to melt off immediately if you slip them a bottle of tetracaine to take home?
Let's look at some cold, hard facts, courtesy of Rebel EM:

As you can see, these were all small case reports or case series. More importantly, in all but one case, the patients with adverse outcomes were abusing topical anesthetics for weeks/months, at higher concentrations than those typically used today.

In recent years, there have been a slew of newer studies from both emergency and ophthalmology literature attempting to refute this dogma. A systematic review of these studies was published in 2015 by Swaminathan et al. in JEM, titled "The Safety of Topical Anesthetics in the Treatment of Corneal Abrasions: A Review."

- This included 2 ED-based, randomized, double blind, placebo-controlled studies on human patients with corneal abrasions.

- There were also 4 studies on patients who underwent photorefractive keratectomy (PRK), an ophthalmologic procedure similar to LASIK where a corneal incision is made, kind of like a corneal abrasion.

- All 6 studies demonstrated that a short course of dilute topical anesthetic provided efficacious analgesia without adverse effects or delayed epithelial healing.

A separate observational chart review in Annals from 2017 by Waldman, et al. looked at 1576 corneal abrasions, 533 of which were simple, who were treated with topical tetracaine 1% for 24 hours.
- Simple was defined as: not large, penetrating, or lacerating, with onset within 2 days from a simple traumatic cause, excluding chemical exposure, contact lens use, infection, retained foreign body, or other contamination.
- 57% of the simple corneal abrasions were given tetracaine, and 14% of non-simple corneal abrasions also received tetracaine.
- While there were ZERO serious complications for ANY patient given 24 hr of tetracaine, the authors did find a slight increase in the number of repeat ED visits in non-simple corneal abrasion pts who were given tetracaine.
Bottom line: 
1) Short-term use of dilute topical anesthetics for simple corneal abrasions for 24-48 hrs is definitely effective and most likely safe, as shown by several recent small but well-designed randomized controlled studies.
2) The risk and safety concerns associated with the use of topical anesthetics is likely overstated, and come from poorer quality evidence such as experimental animal studies, case reports, and case series.
3) At the same time, larger studies should be undertaken to assess safety before the widespread use of this pain management modality can be recommended.
References:
 ·