The casualty came out of a burning vehicle 25 minutes ago, and his fragment wound to the left forearm is controlled with a pressure dressing. Both legs are blistered and weeping from ankle to groin. The skin across his chest is red but intact, and he is a big man, about 90 kg. Your teammate calls it 50 percent and wants two bags of fluid running wide open, and weather has pushed the MEDEVAC back at least six hours.
Bottom line: count only partial- and full-thickness burns, and treat hemorrhagic shock first. If the burn exceeds 20% TBSA, start Lactated Ringer's at 10 mL/hr for each percent burned, adding 100 mL/hr for every 10 kg above 80 kg. Then titrate to urine output.
The TCCC Guidelines dated 01 May 2026 tell the medic to treat a trauma casualty with burns, not a burn casualty with injuries [1]. Facial burns from closed spaces raise concern for inhalation injury, so monitor the airway and oxygen saturation aggressively. Consider an early surgical airway for respiratory distress or desaturation [1]. The guideline sets out the fluid steps as follows [1]:
The Joint Trauma System Burn Care CPG of 10 June 2025 carries the same Rule of 10s, with two differences a medic should know [2]. It names Lactated Ringer's or PlasmaLyte A as preferred and says to avoid normal saline if possible. For a polytrauma casualty who is bleeding, it calls for whole blood or balanced components until hemorrhage is controlled [2]. It also excludes superficial, first-degree burns from the size estimate. Those burns are red, do not blister, and blanch readily [2].
Apply that to the opening casualty. Both legs are 36% by the Rule of Nines, the red chest does not count, and TCCC rounds to the nearest 10%, which gives 40%. At 90 kg, his starting rate is 400 mL/hr plus 100 mL/hr, or 500 mL/hr.
Chung and colleagues at the US Army Institute of Surgical Research built the rule to give deployed providers one starting rate without a 24-hour calculation [3]. They tested it in silico against 100,000 simulated adults, with weight and burn size distributed to match their burn population. The comparators were the modified Brooke formula (2 mL/kg/%TBSA) and the Parkland formula (4 mL/kg/%TBSA) [3].
For 87.8% of simulated patients, the Rule of Ten rate fell between the two formulas. Under 12% fell below the modified Brooke rate, by a median of 14 mL/hr. Under 1% fell above the Parkland rate, by a median of 33 mL/hr; those patients averaged 130 kg with 21% TBSA [3]. The 2024 American Burn Association guideline recommends starting at 2 mL/kg/%TBSA to reduce total resuscitation volume [4]. The Rule of Ten sits close to that low end for most adults.
Caldwell and colleagues reviewed 73 Burn Flow Sheets that came with combat casualties evacuated to the Army Burn Center from 2007 to 2013 [5]. Seventy patients had TBSA recorded both on the flow sheet and at the burn center:
The JTS guideline states the consequence directly: inexperienced personnel often overestimate burn size, and accurate sizing keeps a casualty with a survivable burn out of the expectant category [2].
The burn resuscitation guideline and flow sheet were pushed theater-wide in January 2006. Ennis and colleagues compared 56 casualties with burns above 30% TBSA after that rollout against 62 before it. The groups had similar burn size, full-thickness burn, inhalation injury, and injury severity [6]. The combined rate of abdominal compartment syndrome or death fell from 36% to 18% (p = 0.03) [5,6]. Abdominal compartment syndrome went from 16% to 5% and mortality from 31% to 18%, and neither change alone was significant [5].
In the Caldwell cohort, 26% of patients received more than 250 mL/kg in the first 24 hours. Mortality in that group was 50%, against 14% in patients below 250 mL/kg (p = 0.004) [5]. The high-volume group also had larger burns (61% vs 37% TBSA), higher injury severity scores (30 vs 17), and more inhalation injury (81% vs 47%), so volume and severity cannot be separated [5].
The JTS guideline flags over-resuscitation risk when the hourly rate exceeds 1,500 mL/hr for 2 hours or the 24-hour total exceeds 250 mL/kg [2]. At 8 to 12 hours, it calls for reassessment and consideration of 5% albumin if those criteria are met [2].
When evacuation is delayed, the medic becomes the burn resuscitation team. The JTS guideline gives the endpoints [2]:
Fluids such as sports drinks cause severe hyponatremia [2]. Record every input and output on the flow sheet so the next team can see the trend.
For an adult weighing 40 to 80 kg with burns above 20% TBSA, the initial IV or IO rate is %TBSA × 10 mL/hr [1]. Add 100 mL/hr for every 10 kg above 80 kg [1]. In a simulation of 100,000 adults, the rule fell between the modified Brooke and Parkland rates for 87.8% [3].
No. TCCC states that hemorrhagic shock resuscitation takes precedence over burn shock resuscitation [1]. The JTS guideline calls for whole blood or balanced component therapy until bleeding is controlled and coagulopathy is corrected [2].
TCCC allows oral fluids for burns up to 30% TBSA when the casualty is conscious and able to swallow [1]. The JTS guideline calls for a salt and sugar isotonic solution at the Rule of 10s rate. It advises against the enteral route with abdominal injury, vomiting, or burns above 40% [2].
I have looked at burn resuscitation from two seats, as a State Surgeon responsible for medical readiness and as a HEMS medical director whose crews inherit the fluid plan someone else started. This article gets the central point right. The formula is a starting rate, and the math at the point of injury matters less than what happens over the next six hours. Burn fluids also fail quietly. An over-resuscitated casualty looks fine for hours, and the swelling that threatens the airway or the abdomen shows up on someone else's watch. The most useful thing a medic can carry into a burn casualty is a calm number and the discipline to leave it alone until the urine says otherwise.
That being said, I want to push on the oral resuscitation piece. I would bet few medics have mixed oral rehydration solution under stress or watched a casualty try to drink a liter an hour with burned hands. If your unit expects to hold casualties, that skill needs a lane in training with real volumes, a gastric tube, and someone counting cups. The other gap is the Foley. Without a catheter and a measuring container, the urine output target is a guess, and the plan drifts back to running fluid because it feels productive. I would also drill the Rule of Ten until it is automatic, with casualties above 80 kg on purpose, because the weight adjustment is the step tired people drop.
If you are the medic on the ground, size the burn twice, once at the point of injury and again when the casualty is fully exposed under cover. Write the starting rate and the time on the casualty card before you hand off. If you are a medical officer, audit your unit's last burn training lane for one thing: whether anyone measured output. If you are flying, ask for the hourly totals at handoff and keep the rate unchanged for the first two hours of your leg unless the casualty gives you a reason to move it. The casualty who arrives with a documented trend has a better chance than the one who arrives with a full bag and no record.
— Chester Shermer, MD, FACEP | Emergency Medicine, 25+ Years Clinical Experience | State Surgeon
If you're a combat medic, corpsman, flight medic, or military medical officer (or any clinician treating patients daily) trying to understand how AI will actually impact your clinical practice — not just the hype — I put together a free practical guide. You can download the AI in EM Survival Guide here.
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Relevant Reading on Global MedOps Command:
How to Avoid Becoming an AI Casualty — Dr. Shermer's guide to navigating AI tools in clinical and operational settings without compromising judgment or patient outcomes.
Emergency Department Efficiency Playbook — Practical systems for throughput, triage optimization, and operational efficiency.
Read more from Dr. Shermer on Medium
Connect with Dr. Shermer: LinkedIn — Chester "Chet" Shermer, MD, FACEP.
Related simulation training: EMS-MedSim · EM-Sim · Books by Dr. Shermer