Great article on Tactical medicine and the combat hospitals in kandahar
HEALTH & LIFESTYLE
Battle-Tested Medicine
July 28, 2008, by Sharon Adams
Dr. Allan Hawryluk was dreading the difficult hours ahead—his patient was on blood thinners, and bleeding uncontrollably following a tooth extraction. The Mississauga dentist knew it could be hours before the bleeding was brought under control with sutures and chemical compounds.
Then he tried a sample of the new HemCon dental dressing. “The bleeding stopped completely and immediately,” he said. “I just didn’t believe it.” In the year since he first used it he has gone on to use the new dressing to stop bleeding in the mouth of a National Hockey League player who “was able to return to fight in the third period.” He now keeps HemCon in supply for the “impossible cases” he comes across in his practice.
Since its introduction about a year ago, increasing numbers of dental patients across Canada are benefiting from this new dressing, made from chitosan, which is derived from shrimp cells. They have no idea the product was initially developed to control bleeding of wounded soldiers. It’s just one of hundreds of advances and innovations made or perfected for treatment of the wounded in battle that make their way into civilian health care. “Sometimes the only useful salvage of war is the medical knowledge gained,” says the entry on the dust jacket of the Official History of the Canadian Medical Services, 1939-1945, Vol. II. This has been true throughout human history.
“Advances in frontline external bleeding control are significant,” says Colonel Ron Brisebois, in an e-mail interview from Afghanistan. He mentions other advances—better tourniquets and supplies like HemCon bandages, the concept of damage control resuscitation, and relearning the value of transfusing trauma patients with whole blood.
Even more important, he says, is the knowledge that is passed from those who use it on the battlefield to civilian health care professionals battling on the front lines of domestic trauma and tragedy. Brisebois is also assistant professor of surgery and critical care at the University of Alberta in Edmonton.
Experience in Kandahar is also teaching Canadian military and civilian health care professionals how to deliver better service with limited resources and time, lessons they can use in dealing with Canada’s own beleaguered health care system, says Major Vivian McAlister, professor of surgery at the University of Western Ontario.
During a two-month posting to Afghanistan in the summer of 2007, McAlister saw that civilian and military medical personnel found ways to “expedite care and do terrific rehabilitation” for wounded civilians unlikely to get followup treatment once they left the Canadian-run NATO hospital in Kandahar. For instance, using traction for fractures “takes too long for patients to recover, and they have complications.” Using internal fixation techniques, “you can get a patient up and mobile more quickly and with fewer complications.” Now, he says, orthopedic surgeons are using these techniques in Canada.
As well, battlefield necessity introduced Canadians to a new class of medical professional—the Physician Assistant—that could be adopted in the civilian medical system to ease the service crunch resulting from a shortage of medical professionals and of health care dollars. PAs “replace the general duty doctors taking care of general illnesses in the sick parade,” says McAlister, “and they’re also in the front line doing primary resuscitation of casualties, again replacing general duty doctors.”
There are about 140 of these professionals now in Canadian military service, and as they return to the civilian world, along with doctors and nurses who worked alongside them, there will be a “natural evolution” to incorporate them into the civilian system, says McAlister. That evolution has already happened in the U.S., where about 70,000 PAs have been trained and certified since the 1960s. Manitoba has used ex-military or American-trained PAs since 2002. Two Canadian universities will offer new PA programs in the fall, and Ontario is now running pilot projects. In the civilian world, PAs, who work under doctors’ supervision, can handle a wide variety of tasks, and help stretch resources.
Other military medical advances now benefiting civilians include new surgical and trauma care techniques that improve chances of surviving severe injuries; prosthetics that operate more like real limbs (Thinking Bionics, May/June); new methods for storing blood and blood products; a plethora of new medical devices, like miniaturized respirators; and supplies, like HemCon dressings.
CPL. M.D. SELIG, HMCS FREDERICTON |
Damage control surgery, a technique perfected on the battlefields of Iraq and Afghanistan, is being used by Dr. Jay Doucet, now retired from his 23-year career with the Canadian Forces.
In September 2006, Lt.-Col. Doucet was deployed in Afghanistan during Operation Medusa, the largest NATO operation in the war-torn country since 2002. The objective was to destroy the hundreds of well-armed insurgents who had gathered southwest of Kandahar city, in the district of Panjwai.
“I’d treated about 50 guys in a row with pretty bad injuries,” says Doucet. About a dozen had been killed over the summer and the early September operation started adding to the number of casualties, which would climb about a dozen more by the end of October. This was his third posting to Afghanistan, and his sixth deployment. He’d seen a lot of traumatic injuries, a lot of death.
“After awhile,” he says, “you hope there’s something good that can come out of all this.” It has. He’s now a surgeon at the University of California San Diego Trauma Division, using damage control surgery techniques learned on the battlefield to save lives of accident victims.
Civilian victims of trauma perhaps benefit most from the knowledge and experience that passes quickly and continuously from the military medical community into the civilian world. Trauma is the chief cause of death of young soldiers in battle and for adults under age 45 throughout North America.
Damage-control surgery saves lives of some accident victims that come to the San Diego trauma centre from neighbouring Imperial County, about 250 kilometres to the east. “They get spectacular trauma because people drive at crazy speeds,” over the flat valley land, explains Doucet.
In earlier conflicts, surgeons close to the battlefield took care of injured soldiers until they were stable enough to be shipped back home. “They came back home as passengers,” adds Doucet. “Now patients are coming all the way from Afghanistan or Iraq still in intensive care.”
Current conflicts have taught doctors “we can extend surgery forward (closer to the battlefield) and we can extend intensive care backwards,” says Doucet,
Damage-control surgery involves handling immediate life-threatening injuries, then sending the patient on to the next level of care—often without even closing the woun d—where another surgeon takes over. When U.S. casualties arrive at Walter Reed Army Medical Center in Washington, D.C., a week or so after injury, some “have travelled 8,000 miles (nearly 13,000 km) and had four operations,” says Colonel Craig Shriver, head of general surgery.
Current conflicts have taught doctors “we can extend surgery forward (closer to the battlefield) and we can extend intensive care backwards,” says Doucet, a concept he shares with civilian colleagues.“ I can tell the surgeon to ‘just get in there, find out what’s wrong, fix what needs to be done immediately, then pack the patient up. I don’t care if you even close the skin; just put a sticky drape over everything, put him on a helicopter and get him to us.’ We know from our experience in Iraq and Afghanistan it’s going to be OK.”
Methods used to deal with severe abdominal trauma similar to life-threatening wounds caused by shrapnel, are also changing. One example is the way abdominal swelling is dealt with. “The old approach was to put a big skin graft over the internal organs and have the patient come back one to two years later,” explains Shriver. Unfortunately, the lax skin did not offer good support for internal organs and common complications included fistulas, which allow intestinal contents to leak out into the abdomen. In other cases it led to huge hernias that prevents certain movements like lifting or straining—even rehabilitation exercises.
A two-year recovery period and interference with rehabilitation was not acceptable to the military, which wants to treat troops quickly and effectively. “We decided to go to a new approach,” Shriver adds. And so techniques grew from a battlefield necessity. Severe abdominal injuries couldn’t be closed at the battlefield, so a plastic sheet was laid over the abdomen and patients were sent on to the next level of care, then the next. They’d arrive in Walter Reed with a plastic sheet over a now severely swollen abdomen.
Shriver had seen patients die from intra-abdominal hypertension, where blood pressure drops as the abdomen swells. Recognizing “the swelling will eventually go down,” he developed a new method, called serial abdominal closure, for dealing with these terrible wounds. The damage to the internal organs is repaired, and then sealed with Gortex mesh until the swelling goes down. The mesh, which does not attach to the internal organs, is gradually trimmed as the swelling decreases until finally the wound can be closed—without a huge skin graft. “I did that with a dozen patients and the outcome was definitely better.” Troops could begin rehabilitation for other injuries with the risk of fistula and hernia problems nearly eliminated.
Civilian surgeons, however, were not quick to adopt the procedure. The initial criticism was expense—the large Gortex sheets cost between $6,000 and $10,000. But quickly it was recognized as a cost-cutting procedure, for it eliminated subsequent surgeries for hernia and fistula repair. “If you get one patient with intestinal fistula the cost could easily go into the $100,000 range, even if you can successfully control it.” Now serial abdominal closure is used by civilian surgeons, too.
Civilian trauma experts are also benefiting from battlefield advances in the use of blood products as well as blood replacement techniques. For years, civilian blood services have separated whole donated blood into its various products with the idea that supplies will stretch farther if each patient gets only the blood product they need. For example, oxygen-carrying red blood cells are used in surgery and to treat injuries to prevent organs or limbs dying from lack of oxygen; platelets are used to control bleeding for cancer patients; plasma restores fluid volume in shock patients and provides clotting proteins to stop bleeding.
But blood products cannot be stored for long—red blood cells last about 40 days, plasma can be frozen for up to a year, platelets need to be used within five days, hence the need for blood donations and blood banks. When big battles with lots of injuries use up battlefield blood stores, field hospitals turn to their ‘walking blood banks’—volunteers on site—for donations of whole blood for transfusion.
Field hospital surgeons noted that trauma patients given transfusions of whole blood did better, so they started using more whole blood when they could get it, and they also increased the ratio of plasma to red cells. “In civilian medicine one unit of plasma for every five to 10 units of red cells is thought to be good for the typical situation in surgery,” says Doucet. “But trauma is different,” and can call for a one-to-one ratio. Civilian trauma specialists now commonly use this regime, too, he says.
The U.S. Defense Advanced Research Projects Agency (DARPA) is trying to ensure field hospitals never run out of blood and blood products. It’s developed a freeze-drying method, now in clinical trials, to extend the shelf life of platelets from days to two years, “and we’re trying to get it up to five,” says Col. Geoffrey Ling, a DARPA project manager and critical care physician at Walter Reed. Although it will be a boon to soldiers in the field, “the biggest application I see as a doctor is for cancer patients.”
Another battlefield practice now being tested for civilian use is administration of hypertonic saline to trauma victims, says Dr. David Evans, medical director of trauma services at Vancouver General Hospital, who volunteered for a month-long tour in Afghanistan in January this year.
To keep oxygen circulating to organs, fluid levels must be increased quickly after massive blood loss. Because there’s no time to figure out blood types on the battlefield or at the scene of an accident, a saline solution about as salty as blood is administered. Since battlefield medics have to carry their supplies with them, the solution was concentrated. This hypertonic saline is “a quarter of the size and four times as strong,” says Evans. This battlefield innovation turned out to have other advantages. One problem with regular saline solution is that it seeps out of blood vessels, leaving only about a quarter of the volume in the bloodstream. Hypertonic saline is so salty it draws fluids from other tissue into the bloodstream, boosting volume by about four times over the amount of solution administered. Hypertonic saline may also reduce the “inflammation cascade” that sometimes kills days later, says Evans. As well, there’s evidence it may limit swelling of the brain in response to head injuries, thus reducing brain damage and deaths due to head trauma.
A major international trial of hypertonic saline is now being conducted in about a dozen centres throughout North America, including three in Canada, in partnership with the U.S. National Institutes of Health, but “hypertonic saline is now used quite ubiquitously,” in civilian practice, says Evans.
Dr. Daniel Lindsay, medical director of diagnostic imaging at Selkirk and District General Hospital in Selkirk, Man., has brought back to his civilian practice experience with a pain relief technique—continuous peripheral nerve block—used to treat troops wounded in Iraq and Afghanistan. Anesthetics are administered through a tiny catheter inserted next to nerves serving the wounded area, blocking pain signals before they can be transmitted to the brain. This is a huge cost saving because general anesthesia must be constantly monitored by a trained specialist since it suppresses central nervous system activity. Also, when it wears off, patients need large doses of narcotics for pain control, and they don’t always work, requiring even more specialized care.
“We used ultrasound to go down the sciatic nerve (which runs through the buttocks and down the back of the leg) to insert the catheter to diminish pain for people with amputations,” says Lindsay. “Otherwise they would be on morphine and in brain fog. Instead, they’re sitting up in the morning having breakfast. It’s a huge difference.”
A new technique for handling phantom pain—the sometimes quite severe pain perceived by amputees—has been developed by navy neurologist Dr. Jack Tsao of the Uniformed Services University of the Health Sciences in Bethesda, Md. Patients watch movement of their whole limbs in mirrors positioned where their missing limb used to be. The illusion of two legs moving together somehow tricks the brain into overriding the mismatched nerve signals causing the pain, says Dr. Larry Laughlin, dean of USU. “Some sort of an adjustment is happening in the brain, something both simple and sophisticated at the same time.” Now that it’s been shown to work, researchers are searching to explain how and why it works, and whether it can be adapted for pain relief of other conditions, too.
But perhaps the biggest contributions from battlefield medicine come from simply experiencing it, as Canadian civilian medical professionals do when they volunteer as military reservists or civilian contractors with the Canadian Forces. Many answered the call to serve brief tours to help the forces cope with a shortfall in medical professionals. They come up against situations in the field that they rarely see at home, and bring that new knowledge back with them.
In the field Evans saw “multi-dimensional trauma,” from victims of IEDs (improvised explosive devices) who suffered burns, penetration of shrapnel, blunt force injuries, chemical exposure—all at once. “We never see that here,” in the trauma unit of Vancouver General Hospital, where blunt trauma from car accidents and falls form the majority of his cases. And it’s rare for personnel in Canadian trauma centres to deal with a large number of victims from a single event, but it’s a common experience in a field hospital after a battle, a bomb attack or IED explosion.
But such skills are needed by Canadian health professionals should they ever have to deal with victims of a large-scale natural disaster, like an earthquake, major freeway accident or terrorist attack. “We prepare for it, model it with actors, do simulations,” says Evans. “But we don’t have the experience of managing it on a moment’s notice.”
A suicide bomber will result in 30 or 40 people “hitting the door” (arriving at the field hospital) all at once, says Lindsay. “That in and of itself is something we’re not confronted with here.”
Military experience “really has improved my skill at triage,” adds Lindsay, who was due to return in June from his fifth posting to Afghanistan since December of 2006. “I had to decide who gets what technology and how it’s delivered.”
In disasters, “too often enormous resources are wasted on a tragic circumstance where a casualty is really beyond the help you can offer at the moment. You need to focus what you have on the casualties that will benefit the most,” says Laughlin. In triage, casualties are divided into three categories. Those with severe injuries who require highly sophisticated care that is not available are “in the category we probably cannot help”; the walking wounded “need medical attention, but not immediately”; and “the critical category: patients severely injured and we have the equipment in place to make them better. You want to focus all available resources on patients that will get the greatest benefit out of it,” he explains.
“Dealing with multiple casualties is experience I have now,” says Dr. Steven Wheeler, an anesthesiologist with the Calgary Health Region, based in Calgary’s Peter Lougheed Hospital. “I’ll be able to use it if there’s an unfortunate situation where disaster strikes.”
When asked about important lessons brought back to Canada from their service in the field, Evans, Wheeler and Lindsay all mentioned the opportunity to work shoulder-to-shoulder with a variety of highly skilled specialists on the same cases. “If one person doesn’t have it within his or her experience, some one else will,” and is willing to share that knowledge, says Evans.
There’s a professional commitment to sharing and preserving the knowledge gained in battlefield medicine.
“I think it’s fair to say there are many discoveries that are made on the battlefield itself,” adds Dr. Richard Satava, professor of surgery at the University of Washington Medical Center in Seattle. “Frequently they were work-arounds, or they were things that were thought about previously but either the civilian world couldn’t figure out how to do it, or thought it shouldn’t be done.”
“As we entered and exited many wars, we’ve learned we start out not being very good at military medicine, get very good at it, and by the end of the war have made many advances useful to operations. And then we disband and go home,” says Laughlin. Established in 1972, USU has trained more than a quarter of current U.S. physicians on active duty and is a world-renowned centre of excellence for research. It’s the “memory bank for military medicine,” he says, ensuring the hard-gained knowledge not only isn’t lost before it’s needed again, but continues to be developed through research that very often ends up helping not only military personnel, but civilians.
In other words, knowledge passed on through training and built upon by research is a permanent ‘salvage of war’.
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