Susan Hayes, CertEd, RGN, is vascular research nurse; Simon Dodds, MA, MS, FRCS, is consultant vascular surgeon, department of vascular surgery; both at Good Hope Hospital NHS Trust, Sutton Coldfield, West Midlands.
Many nurses caring for patients with wounds do not have access to a medical photographer and have attempted to capture wound images as an unambiguous record of wound status. This often forms part of an initial wound assessment and is used throughout the treatment programme.
In order to chart the progress of healing it is essential that each photograph is directly comparable with the others (Bellamy, 1995). In the past, this consistency has been difficult to achieve, and the required equipment and specific training was expensive.
With the advent of reasonably priced digital cameras it is now possible for practitioners to capture high-quality images in any clinical situation with minimal training. When transferred to a computer these digital images have many uses that extend beyond simply recording the status of the wound at a point in time (Fig 1).
Monitoring the progress of wound healing
Practitioners regularly face the difficult tasks of choosing the appropriate treatment regime and wound care product, and monitoring the treatment. Caring for a chronic wound can become just a series of dressing changes if there is no element of objective evaluation of the wound healing process. Improvement or deterioration of the wound may be overlooked if there is no standard protocol for periodic wound measurement (Charles, 1998).
Flanagan (2003) observed that nurses often report on the type of tissue found in the wound bed and use this as an indicator of progress towards healing. Unfortunately, vague and subjective descriptions of wound status are open to misinterpretation and are of little relevance when establishing efficacy of treatment, or when used as evidence in litigation.
Houghton et al (2000) and Vowden (1995) stress the importance of photographic documentation, suggesting that a series of images can be used to evaluate colour changes and the condition of the wound bed.
The use of photographs can facilitate diagnosis, particularly of leg ulcers, and provide visual clues to the amount and characteristics of necrotic tissue, granulation tissue and re-epithelialisation, as well as the viability of the wound edge and condition of the surrounding skin (Fig 2).
Improving communication between health professionals
Patients with chronic wounds are often treated by a number of different practitioners in community and hospital settings. The patients may carry their paper-based assessment and treatment records but often need referral to a specialist for advice as part of a multidisciplinary management programme.
Dodds (2002) has documented the problems experienced in the North Birmingham area with continuity of care for patients with leg ulcers, together with communication difficulties between primary and secondary care teams. The introduction of a shared electronic patient record (EPR) that includes high quality digital images is currently providing solutions to many of these challenges.
The NHSnet that links most GP practices, and community and hospital trusts, can be used to send information to shared patient records that can be accessed independently by all clinicians involved in the care of the patient. Fast electronic referral can be made and the use of digital images helps busy wound specialists to prioritise their work.
Many authors have stressed the importance of measuring the physical parameters of wounds on a regular basis in order to assess the response to treatment (Flanagan, 2003; Phillips et al, 2000; Kantor and Margolis, 1998; Vowden, 1995).
Measuring wounds has a number of inherent problems. A wound is a three dimensional skin defect, so theoretically the measurement should include wound volume. A number of techniques are available to measure volume but are impractical for everyday use, require expensive, cumbersome equipment and need the practitioner to have extensive technical training (Plassmann et al, 1994).
Also, trials to evaluate the accuracy of volume measurement have shown that it is subject to significant error (Rajbhandari et al, 1999; Plassmann et al, 1994).
Vowden (1995) points out that most nurses do not have access to sophisticated wound measuring devices and that the common practice of tracing the perimeter of a wound onto clear plastic film and transferring the tracing to graph paper is easy to use, low in cost and requires no special equipment or expertise.
However, the method is inconvenient, subjective, time-consuming and may be painful for the patient or cause cross-contamination.
The tracings can be difficult to store and, unlike an image, provide no information about the appearance of the wound. Wound exudate often clouds the transparent film, requiring it to be removed and replaced frequently during the tracing.
Wound management using digital photography
It has been reported that measuring the area and circumference of superficial wounds from digital images is as accurate as contact tracing and has several advantages (Samad et al, 2002a).
A sequence of images and measurements allows the response to treatment to be presented as a wound area/time graph that can be stored as part of the patient’s EPR so that all clinicians with authorisation to access the EPR can observe the healing profile.
Our experience is that the profile is often linear, with a healing rate (measured in cm2 per week) that is nearly constant for individual patients (Dodds, 2002).
The ability to plot graphs from images that are taken and transferred to the EPR by any community or hospital nurse means that deviations from the projected healing pathway can be quickly identified.
In most cases in which ulcers stop healing, specialist advice can be offered remotely using the EPR without the need for the patient to attend a hospital clinic (Samad et al, 2002b).
Non-healing and slow healing wounds can also be identified in this way and provide justification for offering the patient further specialist investigations such as wound biopsy. Unnecessary morbidity and poor quality of life for patients with chronic wounds can therefore be reduced (Rajbhandari et al, 1999).
Correct use of a digital camera is an easily acquired skill but taking consistently high-quality wound images needs practice. If colour changes are to be used to evaluate the condition of the wound bed, images should be taken with standardised lighting and background conditions (Vowden, 1995).
Plassmann and Peters (2001) stress the importance of using a simple protocol when taking images to ensure that clinicians do not draw the wrong conclusion. For example, Houghton et al (2000) advise reducing glare and shadows, and Charles (1998) reports that changing a patient’s position between images may sometimes result in errors in interpretation.
Patient identification codes, the date and a calibration scale should be included in the view. The camera should be held perpendicular to the wound to allow an accurate assessment of wound size. Any wounds that follow body contours or are too large to be included in one image can be traced and the tracing photographed for accurate measurement (Samad et al, 2002a) (Figs 3 and 4).
When images are used for routine clinical purposes the principle of implied consent is usually sufficient. It is the responsibility of the person taking the photograph and his or her employer to ensure that images are stored in a secure way to guarantee patient confidentiality. When in doubt, or if images are to be used for other purposes, then written consent must be obtained from the patient.
For a new technological advance such as digital imaging to be generally accepted, clinicians have to be convinced of the value of it and informed about its use. Direct experience of benefits should be demonstrated along with with improved healing time and quality of life for patients (Plassmann and Peters, 2001).
An easy to use, inexpensive digital camera linked to telemedicine computer software provides information that is secure, easily stored, rapidly transferred and clinically relevant. It also provides accurate wound measurements.
In North Birmingham we have shown it is possible to use the equipment in nearly any situation, so it is suitable for routine practice as well as for clinical trials of new treatments and dressings, case study analysis and audit. A secure database of images of wounds and their healing pathways has proved an excellent resource for students. Also, patients can see visible evidence of their progress, which is a great psychological boost for them.
Introducing a protocol that includes periodic wound photographs and measurements enables practitioners to provide clear evidence that their care is based on best practice and is effective.
Hayes, S., Dodds, S.R. (2003)Telemedicine: a new model of care. Nursing Times; 99: 5 (Wound Care Supplement), 48-49.