The roadside bomb or improvised explosive device (IED) is the signature enemy weapon in Iraq, and the number one killer of troops. When any high explosive charge is detonated, very hot, expanding gases are formed in millionths of a second. These gases can exert pressures up to or beyond 700 tons per square inch surrounding the explosion, and rush away from the point of detonation at velocities of up to 7,000 miles per hour, thus compressing the surrounding air. The entire blast pressure wave, because of its two distinct phases, a positive and negative or suction wave as the air rushes back, delivers a one-two punch to any object in its path. Depending on the size of the charge and surrounding conditions, these blast effects, whether from an IED, a car bomb, surface mine, or suicide bomber, may cause serious brain injury hundreds of feet or more from the detonation.
When troops are wounded in the field they are evacuated immediately if they have any obvious wounds. But though thousands of troops in Iraq have felt the blast of an IED, and those knocked unconscious are evacuated to a field hospital for evaluation, those who appear uninjured or do not complain of a problem remain on duty.
As specialists in brain injury know all too well, the human brain is the consistency of gelatin and any external force from an explosion shakes it violently; people can suffer brain problems without losing consciousness. Troops with closed head injuries may show no external signs of injury, and appear to be normal. One of the most frightening aspects of brain injury is that brain-injured people often lose the ability to know something is wrong.
Dr. Harriet Zeiner, a brain injury specialist at the VA recently commented on a conference call she had with medical officials at several military facilities including hospitals in Iraq: “One of the things commanders are trying to determine,” she says, “is that after someone has been exposed to five and six concussive blasts are they still battle ready? Frankly, that floored us. You could have very significant effects from one exposure, and now they’re trying to figure out if people who’ve been exposed five and six times should be going back into battle.”
Compared to previous wars in Korea, Viet Nam, World War II, the toll of brain injuries in this war thanks to roadside and car bombs, is astounding. According the Department of Defense, almost 18,000 troops have been wounded. VA doctors say that two-thirds of them have been injured by IED blasts and two-thirds of those exposed to blasts, suffer some brain injury, ranging from a mild concussion to permanent damage. Thousands of unsuspected as well as suspected brain injuries will be one of the major legacies of this war.
Subtle personality changes that may occur as a result of such injuries “would only be noticed by relatives or close friends who know the patient well, and other symptoms could take years to develop. The effects of such injuries may therefore go unnoticed for years or even decades. The difficulty in diagnosis is further compounded by the fact that many of the symptoms of closed head injuries overlap with, or sound similar to those of post-traumatic stress disorder (PTSD).”
A recent JAMA article reports results of combined screening for PTSD, mental impairment, alcoholism, major depression, and other mental disorders of more than 88,000 soldiers returning from Iraq. If I decode the conclusions correctly, the study by physicians in the Division of Psychiatry, Walter Reed and Army Institute of Research, revealed 20% of active and 42% of reserve component soldiers requiring mental health treatment.