To distinguish critical injuries from less serious ones, Ryder is harnessing a noninvasive method called near-infrared spectroscopy. In this technique, Kenneth Proctor, a professor of surgery and anesthesiology, employs a fiber-optic probe. When placed on the head or torso, the probe emits infrared light, which penetrates skin, muscle, and bone to about three-quarters of an inch. Because the underlying tissue reflects light differently depending on how well it is oxygenated, Proctor says, the probe can detect if oxygen levels are declining near the surface of the body. If someone is in shock from internal bleeding, the body shunts blood to the most critical organs—the heart and brain—while constricting blood flow to peripheral tissues. “The probe can tell us whether a patient is just shaken up or truly in physiological shock,” Proctor says.
He and his colleagues are also refining a technique that measures variability in heart rate to get yet another read on just how hurt someone is. The strategy, which involves analyzing a patient’s EKG signal, rests on an intriguing observation: Healthy people have more variable heart rates than sick individuals. The brain-dead fall at the extreme end of the spectrum; their hearts beat steady as a metronome. Thus the degree of heart-rate variability, or rather, invariability, provides a means of assessing a patient’s level of shock.
Ryder is currently testing both near-infrared spectroscopy and heart-rate variability analysis. If either tool lives up to advance billing, Proctor says, they could eventually transform how EMS crews or battlefield medics do triage. “The beauty of these methods is that you don’t have to draw blood or penetrate the body in any way,” Proctor says. “This is Star Trek stuff—a person with minimal training could just press the device against the skin and, a few minutes later, get a readout that indicates this guy is very likely OK but this one needs urgent intervention.”
After triage comes therapy—and in this arena as well, doctors at Ryder are calling upon many new techniques. Borrowing a tool used in organ transplant operations, Ryder surgeons have pioneered a more aggressive approach to treating liver injuries, which rank among the most lethal problems they encounter. The transplant tool, called a Rochard retractor, hooks under the rib cage to lift it up like the hood of a car, providing surgeons unprecedented access to the organ.
Another medical advance in use at Ryder is factor VII, a new genetically engineered product that mimics a clotting agent normally found in blood. Given intravenously, factor VII is typically employed in the middle of surgery, when a trauma patient is at risk from profuse bleeding from many small capillaries. In no time, the floor may become drenched in the patient’s blood.
That’s when trauma surgeons reach for factor VII. It costs $15,000 per treatment, but 19-year-old Andrea Arevalo, who was injured in a 2004 car crash, is proof that it can save lives. Arevalo was on the verge of bleeding to death from a devastating liver laceration when she became one of the first patients at the center to receive factor VII. “They told me it was a miracle I survived,” Arevalo says. Within minutes of treatment, her bleeding subsided.
Perhaps the biggest news of all in trauma medicine, however, does not relate to heroics in the operating theater. It is the surgery that Ryder is not doing that most excites its doctors. As recently as 10 years ago, a standard diagnostic procedure at the center was to insert a syringe into the belly; if blood came out with the fluid withdrawn, the patient would be rushed into the operating room and cut open. By then, however, the bleeding may have stopped on its own. Today, because ultrasound and CT images have improved so dramatically in detail and clarity, doctors often take a wait-and-see attitude with less serious injuries. “That’s great for patients, who used to end up with incisions all over their body just to find out if they were injured,” says Patricia Marie Byers, a Ryder surgeon and chairwoman of the American College of Surgeons committee on trauma care for Florida.
Radiotherapy—another stunning advance—combines diagnosis and treatment in one, further reducing the number of major surgeries to which patients must be subjected. “Say you were bleeding from your liver due to a gunshot wound,” Byers says. “Not so long ago, I would have opened you up, split your liver in half, made it bleed more to find the artery that was damaged, and then sewn you up.” Now, she says, a radiologist will inject contrast dye, pinpoint the problem on an X-ray, and then snake a catheter through an artery to the site and seal it off by injecting a little gel foam. In this way, it is often possible to avoid major operations on critically ill patients—with all the complications and high risk of mortality that such procedures entail.
Ryder is also working on understanding the conditions that set the stage for traumatic injury in the first place. Because almost 70 percent of its patients are the victims of motor vehicle crashes, automobile safety is a major focus of study at the center. Under the guidance of Jeffrey Augenstein, a professor of surgery and director of the center, Ryder has been assembling a huge database that correlates injuries with the type of crash and the design of a vehicle. As a result, the center was the first to document that front air bags, which deploy at over 100 miles per hour, can kill small children in low-speed, otherwise survivable crashes. The same database has also revealed that drivers who wear a shoulder strap but neglect to wear a lap belt are at much higher risk of suffering a fatal liver injury.
