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CHRONIC
DISEASE
CLINICAL GUIDELINES FOR THE SELECTION OF IMAGING MODALITIES
IN THE DIAGNOSIS AND EVALUATION OF CHRONIC WOUNDS
Harold Brem, Sandra Moore, Nidhi Kapil-Pair and Victoria Teodorescu,
Mount Sinai Medical Center New York, NY, USA
Background: Patients with chronic diabetic foot, sickle
cell extremity, venous stasis, and pressure ulcers often receive superfluous
radiographic diagnostic exams.
Hyposthesis: Imaging paradigms assist in directing the choice of treatment
modality and rapidly establish the pathogenesis of chronic wounds.
Methods/Results: We detailed the results of 1700 consecutive patients
over 36 months that presented with chronic wounds, to determine the most
effective imaging decision paradigms. Doppler venous reflux testing is
performed on nearly all patients with leg ulcers between the ankle and
the knee, which details the presence of venous reflux, vein perforators,
and rarely deep vein thrombosis. Pulse volume recordings (PVR), including
arterial brachial indices, are necessary for leg ulcers with decreased
palpable dorsalis pedis or posterior tibial pulses. Arterial duplex provides
further information in diabetic foot ulcers. Magnetic Resonance Angiogram
may, in selective cases, provide an alternative to percutaneous transfemoral
invasive angiography with potentially nephrotoxic contrast. Roentgenograms
were ordered to rule out osteomyelitis. If positive or clinical suspicion
was high, Magnetic Resonance Imaging is utilised to evaluate the extent
of disease and to delimit debridement. Radionucleide bone scanning is
limited to cases of osteomyelitis with possible superimposed ischemia.
Conclusions: All patients with signs of a venous stasis require doppler
venous reflux PVR's are necessary when blood flow in a foot is not absolutely
known. Arterial duplex is particularly useful in diabetic foot ulcers.
MR imaging defines soft tissue pathology, including signs of infection,
better than other modalities.
HEALING TRAJECTORIES FOR VENOUS ULCERS
D. Steed, D. Hill, M. Woodske, M. Robson, University of Pittsburgh
and University of South Tampa, USA
Acceleration of healing venous stasis ulcers is a goal
of clinical trials, but outcome measures are not uniformly accepted. Stringent
criteria of 100% wound closure fail to provide detailed information of
healing over the entire study. Wound healing trajectories have been reported
to be effective outcome measures for diabetic foot ulcers. This study
evaluated wound healing trajectories for venous ulcer treatment.
Methods: Over the past ten years, two multidisciplinary wound research
teams have participated in eight venous ulcer clinical trials enrolling
232 patients. All patients had debridement of the ulcers and extremity
compression dressings. Wound planimetry was used to determine wound area.
Healing trajectories were constructed for wounds that healed (100% closure)
and those that did not (<100% closure) over 20 weeks.
Results: Wound healing trajectories were almost identical for patients
achieving complete healing at the two centres. Trajectories for those
patients with less than 100% closure were also nearly identical at both
centres but were significantly different from those with 100% closure.
60% of all patients achieve 100% healing by 20 weeks. Linear regression
predicted that all patients would heal by 31 weeks.
Conclusions: Total healing is an inadequate outcome measure for healing
venous stasis ulcers. Clinical trials using this measure require excessive
time periods. Trajectories provide more information about the healing
process and allow dynamic comparison at biologically meaningful intervals.
Since wound healing trajectories for patients treated at two centres mimic
one another, shifting the healing trajectory from an impaired to more
ideal course may be a better outcome measure for determining healing of
venous stasis ulcer.
ARTIFICIAL NEURAL NETWORK PREDICTION OF VENOUS ULCER
HEALING
J.V. Smyth, A.D. Taylor and R.J. Taylor, The Willows Centre for Healthcare,
Salford Community Healthcare NHS Trust, Salford, UK
Objective: To develop an artificial neural network (ANN)
for venous leg ulcers to predict key risk factors and the likelihood of
healing on standard treatment at 24 weeks.
Design: Interrogation of a prospectively collected database in a community
specialist leg ulcer clinic, matching risk factors at presentation against
healing rates at 12 and 24 weeks, to determine the significance of each
risk factor as analysed by development of an ANN, compared with standard
statistical methods.
Methods: Three hundred and twenty five unselected patients with 345 venous
leg ulcers presenting consecutively to the Salford Community Leg Ulcer
Service between January 199x and December 1999 were entered onto the database.
An artificial neural network model of risk factors was constructed and
the results compared with standard analysis.
Results: The ANN rapidly produced a model of risk factor hierarchy consistent
with previous studies, identifying chronic ulceration, male sex, ulcer
site, ulcer Base, age, obesity, and mobility as significant factors in
delayed response to four-layer compression. The healing time of 68% of
ulcers could be accurately predicted based on this dataset, and with further
experience, this should be further improved. The ANN therefore offers
a reproducible method of predicting ulcers that are unlikely to heal on
conventional therapy in the community and should be considered for referral
onward to a specialist unit.
THE WOUNDNET: THE FIRST NETWORK OF SPECIALISED WOUND
CARE CENTRES FOR CHRONIC WOUNDS
S. Coerper, F. Pfeffer1, G. Köveker, U.T. Hopt1, H.D. Becker and
the woundnet study group, Department of General Surgery, University of
Tübingen, Germany, 1: Department of General Surgery, University of
Rostock, Germany
Introduction: Wound healing studies are complicated by
various factors that interfere with healing, and clinical efficacy studies
can only be done so far by multicentre trials. These trials are expensive
and time consuming. We therefore established a network of specialised
wound care centres. Here wound care is standardised and wound healing
is documented prospectively by a new comprised wound documentation system.
The data of each centre is collected and the pooled data can be analysed.
After one year, the woundnet is established. In this report the infrastructure
and preliminary data of the woundnet will be discussed.
Results: The data of 3325 chronic wounds with a wide spectrum of various
ethiologies was collected for a mean of 14.4 months in ten wound care
centres. These wounds were treated unsuccessfully before referring to
the wound-net for a mean of 78 weeks. After treatment according to the
comprehensive wound care protocol of the woundnet, the overall healing
rate according to the Kaplan Maier analysis was 80% within 90 days.
Conclusion: We could establish a woundnet in Germany, where a great number
of patients were treated successfully. The large data will help to evaluate
wound healing and the infrastructure will allow us to perform easily prospective
trials for chronic wounds.
INCIDENCE OF CHONIC LEG ULCERS IN THE VETERAN COMMUNITY
IN VICTORIA
Maclellan Donald, Professor of Surgery,The Cangerra Hospital, ACT Australia
Chornic Leg Ulcers are common, particularly in the elderly
population. They consume a large amount of community nursing time, require
considerable expenditure in wound pharmaceutical's and remain an impressive
drain on the health dollar. However, little epidemiological information
is available in Australia. In particular, the extent of the problem in
the veteran community is unknown.
Approximately 4,500 questionnaires were sent out by the Department of
Veterans Affairs representing 10% of the veteran population in Victoria.
The number of responses was 2,226 (49%) of which 78 veterans (3.5%) had
an unhealed chronic leg ulcer at that time. The Research Nurse visited
26 of these veterans at home and the others were interviewed by telephone.
A major finding from this study was that long term ulceration was common.
21% of the ulcers had been present for between one and ten years. A further
24% had been present for more than ten years and several of the ulcers
had been present continuously for forty to fifty years. 49% of these patients
had never been referred to a specialist or hospital clinic and remained
under the care of their local GP.
In Conclusion, despite the efforts of the Department of Veterans Affairs
to provide free high quality and specialist health care to veterans, the
management of chronic leg ulcers was far from an optimum level.
Grant support was from the Commonwealth Health & Medical Council.
REPIFERMIN (KGF-2) IS ABLE TO REVERSE DELAYED HEALING
IN PATIENTS WITH HIGH BACTERIAL BURDEN AT PRESENTATION
Vincent Falanga1, Daniel Odenheimer2 and Partha Bagchi2, 1: Boston
University, Boston University, Boston, MA, USA., 2: Human Genome Sciences,
Rockville MD, USA
Background: The effects of bacterial burden and healing
rates on wound closure were evaluated from a 15 centre, 94 patient study
of the safety and efficacy of Repifermin (KGF-2, keratinocyte growth factor-2)
in patients with venous ulcers.
Methods: Patients were eligible for enrolment in this 12-week study if
they had VU 3-30 cm2 in size and 3-36 months in duration. Bacterial burden
was evaluated by tissue biopsy. Patients with a bacterial colony count
>106/gram of tissue were excluded, but could be enrolled if after initial
wound management, had a subsequent colony count <106. The rate of wound
healing was prospectively calculated based on the modified Gilman equation.
Results: Complete wound closure was observed for 40% (29/72) of patients
with an initial colony count of <106 compared with 9% (2/22) of enrolled
patients with an initial count of >106 (p<0.01). This effect was
independent of wound size and wound duration. For the latter 22 patients,
at least 75% healing was achieved by 62% (8/13) and 11% (1/9) of repifermin
and placebo treated patients, respectively (p = 0.03). Thus, presentation
with a high bacterial count was associated with a failure to heal even
when measures were taken to lower the counts. However, repi-fermin appeared
to ameliorate this situation. The rate of healing within the first four
weeks of treatment was predictive of complete wound closure. An increase
in the rate of healing was observed for the repifermin versus placebo
treated patients.
Conclusions: Bacterial burden at presentation and the rate of wound healing
during the first four weeks of treatment were predictors of complete wound
healing. The data indicate that repifermin may reverse the association
between increased bacterial burden at presentation and delayed wound healing.
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