MEDEVAC Matters

The Department of Defense defines Killed In Action (KIA) as someone who “is killed outright or who dies as a result of wounds or other injuries before reaching a medical treatment facility.”

Someone who is wounded in battle and survives his wounds and is later returned to duty or transported to a higher level Medical Treatment Facility (MTF) is classified as Wounded in Action (WIA).

Whereas someone who “Died of Wounds” (DOW) survived to reach a medical treatment facility after being wounded in hostile action and subsequently died from the wounds received in battle.

(Click on the image to enlarge it.)

Note that if you survive your wounds initially but die while being transported or waiting to be transported from the battlefield (MEDEVAC) to a medical treatment facility, you are classified as Killed in Action (KIA).

Calculating The Survival Rate

The official formulas used for calculating death rates are:

Percentage KIA = [No. killed before reaching a Battalion Aid Station (BAS)/No. of casualties (killed + admitted)] x 100   or

Percentage KIA = [KIA/(KIA+DOW+WIA)] x 100

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Percentage DOW = [No. died after reaching a BAS/No. of admitted] x 100          or

Percentage DOW = [DOW/(DOW+WIA)] x 100

Where admitted is defined as any casualty that stays at a Level II facility or above.

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The U.S. Army is touting a survival rate of 92% for those wounded in battle. If we follow the chart above, it is tracking someone who follows the blue boxes from left to right. It is measuring the success of the medical treatment received at the Medical Treatment Facilities (MTF) for wounded soldiers that are alive upon admission.

What is unknown is what percentage of wounded die while awaiting MEDEVAC transport or during it.

How do changes in patient classification can affect the survival statistics?

Let’s say that for a given period of time there are:

KIA = 10

WIA = 25

DOW = 5

The %KIA = [10/(10+25+5)] x 100 = 25%      and

The %DOW = [5/(5+25)] x 100 = 16.67% which translates into a wounded survival rate of 83.33%

But if change the scenario just a little to say that 3 of the wounded died during the MEDEVAC flight or while waiting for it, this what happens to the statistics:

KIA = 10+3 = 13

WIA = 25

DOW = 5-3 = 2

The %KIA = [13/(13+25+2)] x 100 = 33%      and

The %DOW = [2/(2+25)] x 100 = 7.41% which translates into a wounded survival rate of 92.59%

The Missing Data

This is a gap in understanding each piece of the care and treatment of wounded troops. The records for patients once they enter a MTF are quite reliable and complete for each patient. What is lacking is the information about the MEDEVAC mission itself.

The Army Medical Department did develop a computerized system to track information about each patient and MEDEVAC mission which could then be associated with the patient’s medical treatment and final outcome. Unfortunately, this system is not in wide use in Afghanistan. What is lost is the ability to correlate the survival rates of wounded troops with attributes of the MEDEVAC portion of the time continuum.  For example:

• Does the level of training of the flight medic affect outcomes?
• Does the time from time of wounding to time of delivery of the patient at the MTF correlate with outcomes?
• Does the number of wounded and category of wounded carried on a MEDEVAC correlate with outcomes?
• etc.

In all fairness, the chaotic nature of MEDEVAC missions leaves little time to collect this information. In fact, flight medics are often reduced to writing down critical medical information about the patient for the doctors with a marker on the patient’s skin or on duct tape that is then attached to the patient.

The March, 2011 edition of the NATO Medical Lessons Learned Newsletter highlights this deficiency:

NATO has had overall responsibility for managing the MEDEVAC and Medical Treatment operations in Afghanistan for at least the past 5 years. It was using a two hour MEDEVAC mission time goal. From the official NATO document “Medical Evacuation in AFGHANISTAN: Lessons identified! Lessons learned?” :

When 2007 still 12 percent of all flights were outside the two hour timeline, we were able to reduce that figure to 7 percent in 2008 by improving mainly command and control but also by employing more airframes.

Variation in Survival Rate Over Time

The next topic to cover is the significant variation in the wounded survival rate over time.

Survivability OEF DEC 11 – DMDC Survivability Control Chart

What the chart shows is a survivability rate that varied wildly through 2006. The swings began dampening followed by a significant movement in the survival rate beginning in 2009. The early variability was the result of several factors, including low numbers of KIA and wounded which meant that small changes in the number of deaths could yield the large swings in survival rates.

In 2009 Secretary Gates instructed the Army to fulfill its MEDEVAC missions within 60 minutes, he ordered the U.S. Air Force Pedro units be included in the overall MEDEVAC rotation, the number of MEDEVAC helicopters per company was restored to 15 from the 12 that had been in place since 2005, and more MEDEVAC companies were deployed raising the total number of available MEDEVAC helicopters. Until Secretary Gates stepped in average mission times were substantially longer than 60 minutes. The increased number of MEDEVAC helicopters in Afghanistan paid off with a demonstrably improved survival rate.

The 92% survival rate is excellent. The question is whether there is still room for improvement through modified policies and procedures. The Army essentially is saying “No, we looked at the MEDEVAC function in 2008 and determined that no changes were needed.”

The Army’s Chief Public Affairs Officer issued a statement on January 20, 2012 that included these thoughts:

“Finally, it’s important to remember that the Army would change its policy if battlefield commanders wanted a change. We take our obligation to perform the MEDEVAC mission very seriously. We’re a learning organization and periodically we review our policies to make sure they remain relevant. We looked at the MEDEVAC policy in 2008, but after a review, we determined no change was necessary.

Additionally, neither the International Security Assistance Force or U.S. Forces – Afghanistan has requested a change in policy; because our MEDEVAC crews and aircraft provide the best chance at survival ever seen in warfare, and because — as commanders in Afghanistan have told us — not arming our MEDEVACs and identifying them with the red cross has had no impact on the medical evacuation mission.”

Reality Changed in 2009

The next chart shows the increase in battlefield casualties between October, 2001 and December, 2011 in Afghanistan. The Army is still expressing confidence in the assessment made in 2008 – based on casualty rates about one seventh that of current experience – is still valid. A reasonable person would argue that a seven fold increase in activity rates should prompt a detailed review to see if any improvements are possible to accommodate better the higher tempo environment.

Survivability OEF DEC 11 – DMDC Casualty by Classification Bar Chart

Is 92% As Good As It Can Get?

The real question to ask is whether a 92% rate is as good as it gets. The Army conducted an analysis of combat related Died of Wounds (DOW) deaths between October, 2001 and June, 2009. These were deaths that occurred after the casualties reached a medical treatment facility. As reported in the article “Died of Wounds on the Battlefield: Causation and Implications for Improving Combat Casualty Care” published in the July, 2011 volume of the Journal of Trauma it was reported that a panel of military trauma experts determined that 48.6% of the cases reviewed had non-survivable wounds, while 51.4% DOW cases were classified as potentially survivable. It is reasonable to assume that between prehospital care provided in the field and onboard MEDEVAC flights along with the time lapse for completed MEDEVAC missions there are opportunities for improvements that will save more wounded soldiers.