Among soldiers returning from Iraq and Afghanistan with wounds serious enough to require treatment at Walter Reed Army Medical Center in Washington, DC, nearly one-third have suffered traumatic brain injuries (TBI), a rate significantly higher than that seen in prior conflicts, according to the National Director of the Defense and Veterans Brain Injury Center.
With more than 500 soldiers treated at Walter Reed for brain injuries since the beginning of the conflicts, and another 500 or so treated at the two other hospitals that make up the brain injury center, the military is responding with more neurologists and improved identification and tracking, said Deborah L. Warden, MD, the civilian neurologist and psychiatrist who directs the center.
[The Defense and Veterans Brain Injury Center provides clinical care and and conducts research at three military sites, four VA facilities, and one civilian program. For more about the center and the sites for care, visit www.dvbic.org/dvbicsites.html.]
“Earlier in the conflict I was seeing more of the patients myself because we were short-staffed,” Dr. Warden said. “Pretty quickly we needed to bring on additional staff.”
While an article in the May 19 edition of the New England Journal of Medicine noted that only 12 to 14 percent of combat casualties during the Vietnam War involved a brain injury, the rate Dr. Warden has seen so far at Walter Reed is 31 percent. But, she emphasized, the numbers are not directly comparable.
“Does that mean that 31 percent of all battlefield injuries in Iraq or Afghanistan have a traumatic brain injury? No,” she said. “It's a sample sick enough to get sent to Walter Reed.”
She added: “A lot of the reports from previous conflicts dealt with penetrating injuries. Because society as a whole and certainly the medical societies are more attentive to closed-brain injury [with diffuse axonal injury], milder cerebral injuries are now being reported.” Still, she said, “We do believe that the numbers are somewhat higher” than in previous conflicts.
MORE HELP NEEDED THAN EXPECTED
Warren Lux, MD, joined Dr. Warden's team at Walter Reed a year ago, expecting to work as a clinical neurologist. Instead, he said, “My role has been rapidly evolving. Because of the volume of activity in our center, Dr. Warden needed more help dealing with many of the operational and system issues.”
Now serving as Medical Director of the Defense and Veterans Brain Injury Center, he conceded that the number of brain injuries has outpaced what the military was prepared for. “I wouldn't say it's surprised us,” he said. “It's simply a matter of how things unfolded.”
He attributed the higher numbers to an unforeseeable combination of factors, including evolving enemy tactics, toughened body armor, improved front-line medical care, and better case identification.
“With all those factors thrown together,” he said, “more people are surviving with a brain injury.”
FOUR CONCUSSIONS IN A DAY
Colonel Cornelius Maher, MD, Neurology Consultant to the Surgeon General of the Army, described a case he encountered last November during a six-month stint with a neurosurgical augmentation team at a combat support hospital in Baghdad. The case involved a young marine who came to him as an outpatient referral during the battle in Fallujah.
“He was confused,” recalled Dr. Maher, who now serves as Deputy Commander of the Army's European Regional Medical Command. “He couldn't quite remember all the details of what it means to be a marine.”
He had suffered a concussion within a month after arriving in Iraq in February 2004. He was riding in a vehicle that was blasted by an improvised explosive device (IED). He had been unconscious only momentarily, then awoke and drove on. In August, however, he was exposed to a second IED, had a second concussion, and again woke up after a few minutes and drove on.
“Then, during a fire fight in Fallujah,” Dr. Maher said, “where they were hunting the insurgents in close quarters, door to door, he experienced four concussions in one day. By the end of that day, he was pretty confused. He could identify who he was and where he was, but his reaction times were slow, and he wasn't crisp in answering his sergeants. They were concerned about him continuing with a rifle in his hands.”
Given the high number of concussions involved, Dr. Maher decided to send the marine “out of theater,” to Dr. Warden at Walter Reed Hospital.
In prior conflicts, Dr. Maher noted, soldiers could rarely have been expected to survive so many attacks.
“The bullet-proof vests with ceramic plates that fit into them stop most small-arms fire,” he said. “We also have better helmets that protect soldiers who may take a round to the head. So we are not seeing as many people with thorax wounds and bullet wounds to the head. That's a good thing.”
The unintended consequence, however, is an increase in the number of soldiers surviving with TBI. “Just being in close proximity to an explosion can produce cerebral injury that leads to anything from coma to being knocked out for a minute or three,” said Dr. Maher. Particularly for those with mild TBI, he said, “It can be challenging to figure out that in fact they were exposed to an injury.”
OBSTACLES TO CARE
Part of the problem in diagnosing mild TBI is that many of the symptoms are difficult to distinguish from the effects of stress and sleep deprivation.
“It becomes a really difficult question because now we add the psychological factors of being exposed to combat and being away from home and having irregular sleep cycles,” said Lieutenant Colonel David Wilkie, MD, a neurologist who served six months last year as a “battalion surgeon,” the military's term for a doctor who delivers primary care near the front lines. While serving near Mosul with 650 infantry soldiers, he often joined them on raids and other missions, where he saw soldiers with mild TBI virtually every day.
“The number one non-surgical reason for evacuating a soldier was neurologic,” said Dr. Wilkie, who is now Chief of the Neurology and Physical Medicine Service at Eisenhower Army Medical Center at Fort Gordon in Augusta, GA. “If someone had neurologic symptoms – severe headaches or episodes of loss of consciousness – they would be more likely to be evacuated out of theater, rather than the more common mild injuries that can be handled in theater, such as twisted ankles and sprains.”
He recalled a soldier who had a brief loss of consciousness after a box of ammunition fell on his head. “About a month later, he was riding in a vehicle hit by an IED that led to another brief loss of consciousness,” said Dr. Wilkie. Two months after that, he was in yet another vehicle hit by an IED, and this time the loss of consciousness lasted more than 15 minutes, requiring evacuation to a Baghdad hospital for extubation and CT examination.
But a temporary loss of consciousness cannot always be traced to an explosion, Dr. Maher pointed out. “Was it a seizure, a faint, or was it falling asleep because he hadn't slept in 36 hours?”
“I saw lots of patients who had headache, many related to explosions, but many just related to the large number of people who suffer migraines. I saw many sleep disturbances, but that's also common among soldiers.”
Treatment advice for a soldier with a mild TBI can be especially troublesome in a combat situation, both Drs. Wilkie and Maher agreed.
“We have guidelines for concussions in sports saying when you can permit an athlete to return to play after a concussion,” Dr. Wilkie said. “If there's a loss of consciousness, they're supposed to be removed from competitive athletics for at least a week. But in combat, you may not be able to spare that soldier for a week.”
As Dr. Maher put it, “When the bad guys are running away, you don't call time out. Sometimes there are overarching necessities.”
For all the uncertainties in how best to diagnose and treat mild TBI, however, one thing is clear, said Dr. Wilkie: “It's difficult to keep track of those soldiers and follow them regularly and know what kind of help they're going to need.”
BETTER TRACKING NEEDED
One factor complicating the tracking of these injuries is that the post-deployment health questionnaire filled out by all military personnel when they leave Afghanistan or Iraq does not explicitly ask whether the soldier had experienced a head injury, including one that resulted in temporary unconsciousness. To address the problem, Dr. Warden recommended updating the questionnaire to include such questions – for two reasons.
First, she said, it is necessary to document that exposure has occurred, to facilitate tracking in the future even if the soldier seemingly made a complete recovery. Second, she said, “If someone is still having symptoms, it's a way to help them get attention.”
Many symptoms of even mild TBI are already included in the questionnaire, she noted, including the presence of headache, difficulty concentrating, and depression. Still, she said, “We do believe that it would be appropriate for [questions about TBI] to be included.”
While agreeing that it can be a challenge for neurologists to determine if a mild TBI has occurred, Dr. Maher expressed concern that changes to the questionnaire should not be made too quickly.
“There's been a tremendous amount of work put into the pre-deployment and post-deployment health questionnaires,” he said. “Several years of work went into to designing them to catch everything. We need to go slowly in making sudden changes in programs that are underway.”
ALERT FOR NEUROLOGISTS
For decades to come, civilian neurologists in every state can expect to see patients with neurologic symptoms of TBI that occurred in Iraq or Afghanistan. Although the conflicts are not yet over, the patients are already showing up on neurologists' doorsteps, said Dr. Wilkie.
“Many soldiers are on guard and reserve units,” he said. “Some of their problems may not surface until they go back to their jobs.”
Military literature suggests that 80 or 90 percent recover completely in three months, said Dr. Lux. “Whether that recovery rate will be the same in this conflict or not, we don't know yet,” he said. “But there will be some who will have persistent post-concussive symptoms. When someone comes in with these symptoms, obviously the neurologist is going to have to take a careful history about exposure to concussive injury during the time they were deployed.” Meanwhile, the military is investigating better ways to prevent and treat TBI, said Dr. Lux. As a preventive strategy, researchers are at work on a next-generation helmet to better protect the brain from the effects of a nearby blast. “That is an active area of interest in the military,” said Dr. Lux.
As a treatment strategy, the Pentagon awarded a $12 million grant to contractors developing a robotic “trauma pod” capable of performing surgery on soldiers in the battlefield.
“Is it exciting to think about such developments? Sure,” said Dr. Maher. “Is it going to be done tomorrow? No, I don't think so.” For now, he said, speaking both as a soldier and a doctor, “Sometimes the best medical care in a combat situation is hot steel going in an outward direction.”
ARTICLE IN BRIEF
✓ Neurologists are responding to a greater than anticipated number of traumatic brain injury among US soldiers in Iraq.