OBJECTIVE -Tissue oxygen supply is crucial for wound healing. Especially in diabetic foot lesions, the chances for healing are mainly dependent on the presence or absence of ischemia. This study investigates the impact of the tissue O2 analysis system "O2C" for noninvasive quantification of tissue oxygenation in diabetic foot ulcer patients.RESEARCH DESIGN AND METHODS -O2C assessed relative blood flow (flow), flow velocity (velo), and hemoglobin concentration (rHb) and hemoglobin oxygenation (SO 2 ) at 2 and 6 mm depth (means Ϯ SE). 1) Measurements were performed on intact skin of the forefoot and forearm of 20 healthy volunteers on 2 consecutive days. 2) Parameters were assessed on intact skin of the forefoot of diabetic foot ulcer patients (n ϭ 14). 3) Measurements were performed directly at the wound site in diabetic patients (n ϭ 14).RESULTS -1) Flow, velo, rHb, and SO 2 at 2 and 6 mm depth were not significantly different when measured at 2 consecutive days. 2) There were no significant differences between diabetic subjects and healthy volunteers. Only flow in 6 mm depth was significantly higher in diabetic subjects (75 Ϯ 13 vs. 51 Ϯ 0.4 arbitrary units [AU], P Ͻ 0.05). When diabetic foot ulcer patients were split into healers and nonhealers, initial readings of SO 2 at 2 mm (32 Ϯ 6 vs. 44 Ϯ 3%, P Ͻ 0.05) and flow in 6 mm (28 Ϯ 1 vs. 51 Ϯ 0.6 AU, P Ͻ 0.05) were significantly reduced in nonhealers compared with control subjects, whereas in healers flow in 6 mm (70 Ϯ 0.6 vs. 51 Ϯ 0.6 AU, P Ͻ 0.05) was significantly higher than that in control subjects. 3) Initial SO 2 , rHb, flow, and velo were significantly lower in nonhealing compared with healing wounds.CONCLUSIONS -O2C is a new reliable and valid method for noninvasive measurement of tissue oxygenation and microvascular blood flow in patients with diabetic foot ulcers. Diabetes Care 27:2863-2867, 2004F oot ulcers are severe long-term complications in diabetic patients. In addition to local wound therapy, adequate tissue oxygenation is crucial for healing since oxygen is necessary for collagen formation, bactericidal activity of neutrophils, and endothelial cell function. Prognosis of diabetic foot lesions is mainly dependent on the presence or absence of tissue ischemia. However, quantitative assessment of peripheral perfusion and microcirculation is still challenging. Different methods like Doppler ultrasound or angiography are able to evaluate macrocirculation, but a reliable, easy technique to assess microcirculation, i.e., tissue perfusion, is not available. Previous studies have shown that healing might be predictable by measurement of transcutaneous oxygen tension (TcPO 2 ) (1-3). If TcPO 2 is Ͻ30 mmHg, complete healing cannot be expected (4). However, TcPO 2 is only a qualitative, not a quantitative, approach for evaluating peripheral perfusion and has a main limitation due to the need for heating the skin before measurement. This affects the resistance of skin vasculature and attenuates reflex mechanisms.Lightguide tissue spectrophotometry (O2C), ...

OBJECTIVE—Several well-accepted classification systems are available for diabetic foot ulcers. However, there are only a few and scientifically not validated severity scores. The aim of this study was to establish a new wound-based clinical scoring system for diabetic foot ulcers suitable for daily clinical practice anticipating chances for healing and risk of amputation. RESEARCH DESIGN AND METHODS—Four clinically defined parameters, namely palpable pedal pulses, probing to bone, ulcer location, and presence of multiple ulcerations, were prospectively assessed in 1,000 consecutive patients. In the next step, a new diabetic ulcer severity score (DUSS) was created from these parameters. Palpable pedal pulses were categorized by the absence (scored as 1) or presence (scored as 0) of pedal pulses, while probing to bone was defined as yes (scored as 1) or no (scored as 0). The site of ulceration was defined as toe (scored as 0) or foot (scored as 1) ulcer. Patients with multiple ulcerations were graded as 1 compared with those with single ulcers (scored as 0). The DUSS was calculated by adding these separate gradings to a theoretical maximum of 4. Wounds were followed-up for 365 days or until healing or amputation if earlier. Probability of healing and risk of amputation were calculated by the Kaplan-Meier method. RESULTS—Uni- and multivariate analyses showed a significantly higher probability of healing for patients with palpable pulses, no probing to bone, toe ulcers, and absence of multiple ulcerations. When patients were divided into subgroups with the same DUSS, we found significantly different probabilities for healing. We showed a decreasing probability of healing for ulcers with a high DUSS, concurrent with increasing amputation rates. An increase in the DUSS by one score point reduced the chance for healing by 35%. Similarly, the higher the ulcer score, the larger the initial wound area, the longer the wound history, and the more likely the need for surgery or hospitalization. CONCLUSIONS—The DUSS categorizes different ulcers into subgroups with specific severity and similar clinical outcome. Using this score, the probabilities for healing, amputation, need for surgery, and hospitalization are predictable with high accuracy. This might be useful for the anticipation of health care costs and for comparison of subgroups of patients in clinical studies.

No abstract

With the dramatic increase in the aging population, the study and care of wounds in the elderly have become priority topics for both researchers and clinicians. The effects of aging on wound healing in humans have remained controversial. The study was a 5-year epidemiological evaluation of standardized data collected regularly during patients' visits at a specialized Wound Care Center with the aim to determine the key factors influencing the healing of chronic lower extremity wounds. In this analysis of 1,158 chronic wounds, the frequency of wound closure was statistically significantly lower in older patients compared with younger patients. The share of closed wounds decreased by nearly 25% in the elderly patients (>or=70 years). The relationship between the patient's age and the proportion of wound closure was nonlinear. The effect of aging on the frequency of wound closure of chronic wounds became clinically apparent after age 60. The chronicity of the wounds was illustrated by their recurrent nature, their long duration, the presence of multiple wounds, and the frequency of concurrent infection. Comorbidity was documented by the coprevalence of up to three underlying diseases related to impaired wound healing. The present study clearly showed that aging affects chronic wound healing negatively.

Our data indicate that ultrasound might have a better diagnostic power for detecting chronic osteomyelitis in the diabetic foot than PFR and has similar sensitivity and specificity as BS. MRI is superior to the other three methods. We conclude that the use of ultrasound in the management of the diabetic foot is worthy of further investigation.