In addition to providing HBO therapy, we also provide evaluation and treatment of problem wound patients. Our Transcutaneous Oxygen Measurement (TCOM) capability allows us to differentiate wounds into those that have adequate oxygenation for spontaneous healing (and thus, are not healing due to some other factor), those wounds that will likely benefit from HBO, and those that will likely benefit from revascualrization. Since we are a consult service, the referring phyicians will retain primary control over thier patients' care and our involvement in the ongoing wound care can be customized to the individual phyician's needs and desires.
The Trans-Cutaneous Oxygen Measurement Test, or TCOM, is a method used to help determine whether a wound will benefit from hyperbaric oxygen therapy.
Hyperbaric oxygen therapy aids in the healing of hypoxic wounds. Therefore, if a wound is not hypoxic, HBO will be of no benefit and other issues rather than lack of oxygen are likely responsible for the wound's poor healing. However, because the high level of oxygen generated by HBO must reach the hypoxic tissue via the bloodstream to be effective, if blood flow to an area is below a critical value, HBO will be of no benefit because the oxygen cannot reach the compromised tissue. In other words, for HBO to enhance healing, blood flow to the wounded tissues must be inadequate, but not absent.
The TCOM is used to assess oxygenation in compromised tissues. During the test, sticky probes are attached to the skin surrounding the wound. These probes then measure the oxygen tension in the tissues. The first step of the test measures the tissue oxygenation on room air. Studies have shown that if tissues have an oxygen tension > 30 mmHg in non-diabetics or > 40 mmHg in diabetics, they should heal spontaneously and some other factor (poor nutrition, smoking, elevated blood sugar, sub-optimal wound care, etc.) is responsible.
If the oxygen tensions are below these thresholds, the second stage of the test measures the oxygenation of the tissues while the patient breathes 100% oxygen. An increase of tissue oxygenation during this stage indicates that the tissues are getting enough blood flow that HBO should enhance wound healing. An inadequate response to oxygen usually indicates that the patient has some form of arterial insufficiency and may benefit from vascular work-up and intervention.
Occasionally, if the results of the second stage are inconclusive, a third stage, which consists of breathing 100% oxygen at depth in the chamber, is performed. Again, an increase in tissue oxygenation indicates that HBO might be of benefit, while an inadequate response indicates that it likely won't.
In summary, the TCOM test allows us to determine a wound's suitability for hyperbaric oxygen therapy.