In the presence of wheelchair-bound Bill "Willie" Shoemaker – America’s winningest jockey until an auto accident severely injured his spine in 1991 – Sandia representatives last Friday signed a $5.76 million cooperative research and development agreement (CRADA) with California-based Numotech, Inc., a company that conducts research about wounds and designs new treatments.
The CRADA engages Sandia researchers in developing inexpensive sensors and lightweight pumps to simplify operation of Numotech’s unique oxygen-bath technique for healing wounds, pressure sores, and pressure ulcers – quickly, and with reduced scarring.
The product – helpful to the elderly, paraplegics, diabetics, and victims of burns and severe abrasions – should be available for home use in approximately three years. The treatment is called Topical Hyperbaric Oxygen Treatment (THOT). It involves surrounding the injured part with a plastic bag filled with a slightly higher percentage of oxygen than the atmosphere provides, and at a slightly higher pressure. Numotech is contributing $1.51 million in cash and $3.9 million in in-kind contributions. The remaining money is overhead and depreciation waived by DOE.
Among those attending the CRADA signing, in addition to Shoemaker, were Sandia Executive VP John Crawford; Numotech President Dr. Robert Felton; technique discoverer and developer Dr. Madelene Heng, a professor at the UCLA School of Medicine and Chief of Dermatology at the Veterans Administration Center in Sepulveda, Calif; and Michael Kleinman, board member of the Paralysis Project of America, a Los Angeles-based nonprofit organization that advances spinal cord research.
The problem of pressure ulcers
According to Shoemaker, "People with spinal cord injuries are very susceptible to skin breakdown and hence, development of pressure ulcers. Statistics indicate that the incidence of pressure ulcers is about 50 percent among those with spinal cord injuries. The statistics get more ominous, though. Of those with pressure ulcers, an impressive number will be hospitalized as a direct result of that ulcer. Of those so hospitalized, an appalling number will die as a direct result of the ulcer."
Shoemaker became interested in Numotech’s oxygen-bath technique when, after surgery on a bone infection that followed upon a pressure sore, he took a week of the Numotech oxygen-bath treatments and was sufficiently healed to return to the track immediately. "My doctors tell me that it would have normally taken four to five weeks to heal that sore," he says.
Pressure ulcers plague paraplegics, diabetics, and victims of burns and severe abrasions, all of whom suffer from loss of sensation in their bodies.
Pressure unfelt and therefore unrelieved can prevent blood from flowing in skin capillaries, says John Bode (5009), who helped arrange the CRADA. Under such conditions, the skin breaks down in minutes, and necrosis – the localized death of living tissue – can occur. Affected areas can go from necrotic to gangrenous, extend from skin to bone, and require amputation of the affected part. Such situations are avoided in normal bodies by the tendency to wiggle, which allows blood to flow through capillaries.
Reduce necessity of amputations
"If our system were widely deployed, it would reduce the number of amputations caused by many medical conditions in this country by half," says Robert Felton, a 1977 University of New Mexico graduate who has a doctorate in neurophysiology from UCLA. "One out of every three elderly people suffer from these problems. New Mexico will benefit immediately from being a pilot site with immediate access to the technology."
The system, developed over 20 years by Heng, uses hyperbaric oxygen in a plastic bag around the affected part. In this technique, the oxygen is at only slightly higher pressures than ordinarily experienced.
The technique is different from oxygen-based healing sometimes attempted within metal chambers pressurized to two to three atmospheres and in which high oxygen concentrations are breathed by the patient. Pressurized chambers are expensive, and require extensive technical monitoring, upkeep, and cleaning. Overly lengthy treatments can be dangerous. Excessive oxygen delivered to a clotted wound, rather than stimulating healing, may feed microorganisms or create free radicals, harming the patient whose clotted blood is unable to produce the anti-free-radical components normally found in flowing blood, says Madelene Heng.
Lower pressures, lightweight equipment
Researchers in the Sandia-Numotech venture make use of much lower pressures and intend to develop accurate, simple, lightweight, inexpensive sensors and pumps. They hope to make the benefits of only mildly oxygen-rich care available to the public at far lower costs.
Sensors will permit automated or semiautomated monitoring for hospital nurses not specifically trained for the task and, in a later stage of development, enough simplicity of operation for patients to use the equipment at home. Safety features will include automatic shutdown if pressure levels are too high or if the predetermined treatment time is exceeded. For home use, a highly portable, user-friendly, inexpensive oxygen delivery system will be developed by Sandia.
Said Shoemaker in a prepared statement: "This joint effort envisions a process of health care where topically applied hyperbaric oxygen can be taken into the home, thus obviating the need for expensive equipment or hospitalization in many cases. I also learned that this process can be used for the treatment of burns, diabetic, venous, and arterial ulcers and as a postsurgical treatment to accelerate healing."
"We’ll be trying to find out the optimum amount of oxygen to use for the treatment to be maximally successful," says John. "Some chemical reactions work against each other, in control molecules that cause a reaction to go one way or another, and it’s not understood how to make it most effective in an engineering sense. We know the technique works, but we want to understand its boundaries."
A simple internal pressure sensor
The technique is, amazingly, currently operated by feel by Heng, says Sandia researcher Mark Vaughn (2413). "She has to go around in her hospital and push with her fingers on the oxygen bag to estimate the pressure. And, she has to train every person who uses the technique to feel how much pressure is enough."
Mark and project manager Keith Miller (9652) for starters have applied for a patent (through Sandia) on a spring-loaded internal pressure sensor, made of plastic "cheap enough to be thrown away," that is nonelectrical and can be read by a nurse, who may be monitoring the health of a number of patients, from 10 feet away.
"Heng’s is really an astonishing technique," says Mark. "Even at the microscopic level, wounds seem to heal without scar tissue."
In addition to its humanitarian and economic benefits, the project is of interest to Sandia because sensors developed to detect minute amounts of effluents expelled by healing wounds during the Topical Hyperbaric Oxygen Treatment are similar to ones used to detect minute amounts of trace elements from aging nuclear weapons to indicate their state of reliability.