The catheter itself works like a tiny soaker hose, delivering the medication over the designated area in an even flow, Orsini said, and the volume accuracy is similar to that of any infusion pump.

Most important, said James Lee Sorenson, chief executive officer, it "opens up control of pain locally as opposed to systemically." That means patients are more comfortable and maintain range of motion and mobility. It can be worn home, so patients can leave the hospital sooner and still be pain-free. In general, regional pain control seems to promote faster healing and it's more convenient and comfortable.

Physicians like Buckenmaier are especially interested in reducing the dangers narcotics can pose in an already bad situation. On the battlefield, he said, "the answer to more pain is 'more-phine.' You can only do that to a certain point, before they stop breathing or are so sick they can't take any more."

Equally troubling is the prospect of what happens when pain gets out of control.

If you stub your toe, he explained, it hurts. The next day, it hurts even worse. That's a phenomenon called "wind up," a protective mechanism the body likes to use to keep you from reinjuring yourself — if your toe throbs, you're more careful with it.

Researchers have found that if they can turn off the pain, when they remove the block and the patient starts feeling sensations again, "it will not be near the level he has immediately after injury," Buckenmaier said.

Though pain is poorly understood, inadequately controlled pain can become chronic pain, persisting after the precipitating injury has healed. And chronic pain is one of the most costly, debilitating and frustrating medical conditions.

A pump like ambIT is often used along with a small amount of narcotic like morphine, especially during surgery. It works well together without running the risk of too much narcotic.

There are downsides to regional pain management, Buckenmaier said, such as the fact it's invasive. The needle has to be placed right next to the nerves and any drug has toxic levels that must be avoided. But it's easier with something like novocaine than with a narcotic, especially without monitoring resources in plentiful supply.

But the pain control is excellent, and for the physician it has a "small logistics footprint and provides a product at the end of the case who's alert and able to participate in evacuation. An alert soldier requires less resources, fewer people who have to watch him. It literally can be the difference between life and death."

Outside the military, the benefit is dollars. Patients can go home sooner with fewer complications.