No question, the past few decades have brought us a wealth of technologic advances for the treatment of wounds. As health care practitioners, however, we know there is no substitute for time-honored clinical acumen in diagnosing impending and advancing wounds. In other words, we use our senses-sight, touch, hearing, and even smell-to assess the status of the patient's wound.

Making Sense of Assessment

With our sense of sight, we look at the patient's wound to assess its color, its capillary permeability, and its size and depth. We observe for any deviation from normal, red, healthy tissue with good capillary filling.

We palpate the patient's wound, using our sense of touch to check the wound's consistency and to determine the health of the subjacent tissues. We do this by pressing lightly on the area of interest and testing for subjective pressure sensations, using terms such as firm, boggy, or normal to describe the consistency of the tissue. Palpating an impending or fully developed wound may trigger tenderness or pain, as reported by the patient. Through our peripheral senses we can also perceive and describe variations in temperature at the tissue of interest.

We even use our sense of hearing: We listen to the patient, to his or her family members, and to our fellow practitioners as they give their historical accounts of a particular wound. We use this history as a record of how the wound developed, how it was diagnosed, how it has progressed or regressed, and what has and has not worked in treating it.

The Scent of a Wound

What about the sense of smell? What role does it play in our diagnostic workup?

Odor has been of clinical interest-and presumably of diagnostic value-for practitioners since antiquity. For example, a characteristic fruity odor to the breath is known to be associated with ketosis in patients with diabetes. Other disease processes have similarly distinct odors.

A wound should be relatively free of odor, although it is sometimes a challenge to maintain the wound environment in a relatively "euodorous" state. Manufacturers have incorporated odor-eliminating or odor-stabilizing products in wound dressings and cleansing agents to help. In my opinion, the person who develops a product that truly eliminates wound odors should win the Noble Prize in medicine!!

An odor emanating from the wound may be attributable to the cleanliness of the wound environment and/or to a dressing that has not been changed on a regular basis. In addition, necrotic tissue gives off an unpleasant odor, and anaerobes typically produce a distinctive caustic or rancid odor.

Even wounds that have been covered by some hydrocolloid dressings can have an odor when the dressing is removed. This odor generally dissipates after the wound is cleansed. If it does not, the patient may have another pathology that warrants attention.

The (Artificial) Nose Knows

From a diagnostic point of view, researchers are looking to match advances in computer technology with the human ability to characterize and distinguish smells. Several researchers have developed simple, accurate, and noninvasive tools that enable machines to smell.

For example, the Royal Tropical Institute, Amsterdam, The Netherlands, and Cranfield University, Cranfield, Bedfordshire, United Kingdom, have collaborated on developing a portable device that can rapidly detect, identify, and analyze Mycobacterium tuberculosis in culture, sputum, and breath samples.1 The ultimate goal is to develop a simple breath analysis device that can distinguish tuberculosis from other lung diseases.1

The E-Nose, developed in the 1980s by scientists at the Argonne National Laboratory, Argonne, IL, has been used by C. William Hanson III, MD, University of Pennsylvania, Philadelphia, PA, to analyze the exhaled gases of intubated and mechanically ventilated patients. The device correctly identified the study patients who had already been diagnosed with pneumonia, distinguishing them from patients who did not have pneumonia.2 Dr Hanson is now working with Erica R. Thaler, MD, on using the E-Nose to diagnose sinusitis.2

Researchers at Cranfield University's Cranfield Postgraduate Medical School are refining their Diag-Nose, which was developed in the late 1990s to identify pathogens in urine. With the device, they have been able to cut the time to detect the 2 most common causes of urinary tract infection-Escherichia coli and Proteus mirabilis-from 2 days to less than an hour, with 98% accuracy.2

Science Fiction, Science Fact

Although we rely on our time-honored diagnostic sensibilities, we must be prepared to embrace the possibilities on the horizon. What seems like science fiction could soon be science fact. In the future, we may use "electronic noses" similar to the ones described above to help us diagnose a variety of infectious processes,3,4 including infectious processes in our patients' chronic wounds.

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