Morphological characteristics of the human skin over posterior aspect of heel in the context of pressure ulcer development

Effectiveness of Sucrose Octasulfate Dressing in the Treatment of Neuro-Ischaemic Diabetic Foot Heel Ulcers: A Retrospective Single arm Study

The study aimed to evaluate the effectiveness of the use of sucrose octasulfate impregnated dressing (TLC-NOSF [Technology Lipido-Colloid-Nano-OligoSaccharide Factor]) in the management of persons with neuro-ischaemic heel diabetic foot ulcers (DFUs). Consecutive patients who referred for an active non-infected neuro-ischaemic heel DFU belonging to grade IC (superficial) or IIC (deep to tendons, muscle or capsule) according to Texas University Classification were included. All patients were managed by a pre-set limb salvage protocol in the respect of International guidelines and the TLC-NOSF dressing was used as primary and specific dressing. Patients were evaluated any 2 to 4 weeks until wound healing or different outcomes. Primary outcome was the rate of complete wound healing after 24 weeks of follow-up. The secondary outcomes assessed the healing time, the rate of wound regression, the re-ulceration in the case of complete healing and the safety. Thirty patients were included. The mean age was 67 ± 11 years, 17 (56.7%) were male, all of them were affected by type 2 diabetes with a mean duration of 18 ± 7 years. Twenty patients (66.7%) showed deep ulcers (grade 2 of Texas University Classification); the mean TcPO2 at the inclusion was 42 ± 7 mm Hg. Twenty-two patients (73.3%) healed by Week 24. The mean time of healing was 84 ± 32 days, 2 (6.7%) patients had ulcer relapse after healing, 28 (93.3%) had wound regression >50%, 2 (6.7%) had mild infection, 1 (3.3%) reported major amputation. No serious adverse events related to TLC-NOSF dressing or local reactions were reported. This current study showed the potential benefit of sucrose octasulfate for treating neuro-ischaemic heel DFUs in addition to the standard of care.

Wound location is independently associated with adverse outcomes following first-time revascularization for tissue loss

OBJECTIVE

Few studies adequately evaluate the impact of wound location on patient outcomes after lower extremity revascularization. Consequently, we evaluated the relationship between lower extremity wound location and long-term outcomes.

METHODS

We reviewed all patients at our institution undergoing any first-time open surgical bypass or percutaneous transluminal angioplasty with or without stenting for tissue loss between 2005 and 2014. We categorized wounds into three distinct groups: forefoot (ie, toes and metatarsal heads), midfoot (ie, dorsal, plantar, lateral, medial surfaces excluding toes, metatarsal heads, or heel), and heel. Limbs with multiple wounds were excluded from analyses. We compared rates of perioperative complications, wound healing, reintervention, limb salvage, amputation-free survival, and survival using χ², Kaplan-Meier, and Cox regression analyses.

RESULTS

Of 2869 infrainguinal revascularizations from 2005 to 2014, 1126 underwent a first-time revascularization for tissue loss, of which 253 patients had multiple wounds, 197 had wounds proximal to the ankle, 100 had unreliable wound information, and 576 (forefoot, n = 397; midfoot, n = 61; heel, n = 118) fit our criteria and had a single foot wound with reliable information regarding wound specifics. Patients with forefoot, midfoot, and heel wounds had similar rates of coronary artery disease, hypertension, diabetes, and smoking history (all P > .05). Conversely, there were significant differences in patient age (71 vs 69 vs 70 years), prevalence of gangrene (41% vs 5% vs 21%), and dialysis dependence (18% vs 17% vs 30%) (all P < .05). There were no statistically significant differences in perioperative mortality (1.3% vs 4.9% vs 4.2%; P = .06) or postoperative complications among the three groups. Between forefoot, midfoot, and heel wounds, there were significant differences in unadjusted 6-month rates of complete wound healing (69% vs 64% vs 53%), 3-year rates of amputation-free survival (54% vs 57% vs 35%), and survival (61% vs 72% vs 41%) (all P < .05). After adjustment, compared with forefoot wounds, heel wounds were associated with higher rates of incomplete 6-month wound healing (hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.1-2.]), major amputation or mortality (HR, 1.7; 95% CI, 1.1-2.7), and all-cause mortality (HR, 1.8; 95% CI, 1.1-3.0), but not major amputation alone (HR, 2.1; 95% CI, 0.9-4.5). In open surgical bypass-first patients, heel wounds were solely associated with an increased risk of all-cause mortality (HR, 1.7; 95% CI, 1.1-2.8), whereas heel wounds in percutaneous transluminal angioplasty-first patients were associated with an increased risk of incomplete wound healing (HR, 2.2; 95% CI, 1.3-3.7), major amputation or mortality (HR, 2.3; 95% CI, 1.1-5.4), and all-cause mortality (HR, 2.8; 95% CI, 1.1-7.2).

CONCLUSIONS

Heel wounds confer considerably higher short- and long-term morbidity and mortality compared with midfoot or forefoot wounds in patients undergoing any first-time lower extremity revascularization.

Reliability of the Bates-Jensen wound assessment tool for pressure injury assessment: The pressure ulcer detection study

The Bates-Jensen Wound Assessment Tool (BWAT) is used to assess wound healing in clinical practice. The purpose of this study was to evaluate BWAT use among nursing home residents with pressure injury. Findings and reliability estimates from the BWAT related to pressure injury characteristics (stage, anatomic location) and natural history (resolved, persisted) among 142 ethnically and racially diverse residents are reported. In this prospective 16-week study, 305 pressure injuries among 142 participants (34% prevalence) are described by stage, anatomic location, and BWAT scores. Visual and subepidermal moisture assessments were obtained from sacrum, buttock, ischial, and heel ulcers weekly. Participants were 14% Asian, 28% Black, 18% Hispanic, 40% White with a mean age of 78 ± 14 years, and were 62% female; 80% functionally dependent (bed mobility extensive/total assistance) and at risk (Braden Scale score 14 ± 2.7). The reliability coefficient for BWAT score (all participants, all anatomic locations) was high (r = 0.90; p < 0.0001; n = 1,161 observations). Weighted Kappas for characteristics ranging from 0.46 (skin color surrounding wound) to 0.79 (undermining) were consistent for all participants. BWAT scores showed strongest agreement coefficients for stage 4 pressure injury (r = 0.69), pressure injuries among Asian and White ethnicity/racial groups (r = 0.89, and r = 0.91, respectively), and sacrum anatomic location (r = 0.92) indicating scores are better correlated to fair skin tones. Lower agreement coefficients were demonstrated for stage 2 pressure injury (r = 0.38) and pressure injuries among African American and Hispanic ethnicity/racial groups (r = 0.88 and 0.87, respectively). BWAT scores were significantly different by pressure injury stage (F = 496.7, df = 6, p < 0.001) and anatomic location (F = 33.76, df = 8, p < 0.001). BWAT score correlated with pressure injury natural history (ulcer resolved 18.4 ± 7.4, ulcer persisted 24.9 ± 10.0; F = 70.11, df = 2, p < 0.001), but not with comorbidities. The BWAT provides reliable, objective data for assessing pressure injury healing progress.

The Ability of Fluorescence Angiography to Detect Local Ischemia in Patients With Heel Ulceration

Heel ulcerations are a significant burden of care in both hospital and long-term care settings. The presence of peripheral arterial disease as a contributing factor to delayed healing is often not recognized, resulting in prolonged healing and high patient morbidity and mortality. Formal vascular evaluation and intervention is often not performed as these patients can have palpable pedal pulses while having localized ischemia of the heel. As routine noninvasive vascular studies can be affected by medial calcinosis and collateralization and do not specifically assess tissue perfusion to the heel, a false sense of security of adequate perfusion for healing can result. Indocyanine green fluorescence angiography (ICGFA) allows for real-time visualization and objective assessment of site specific tissue perfusion not limited by the factors that can make routine noninvasive vascular studies unreliable or unobtainable. A retrospective medical record review of a subset of patients with chronic heel ulceration from a prospective institutional review board-approved study in which serial ICGFA was performed during their treatment course was performed. ICGFA was able to identify local heel ischemia and expedite vascular intervention. ICGFA should be considered as an additional vascular study in patients presenting with chronic, nonhealing heel ulcerations.

LEVELS OF EVIDENCE

Level IV: Diagnostic, Case series.

Subepidermal moisture detection of heel pressure injury: The pressure ulcer detection study outcomes

We examined subepidermal moisture (SEM) and visual skin assessment of heel pressure injury (PrI) among 417 nursing home residents in 19 facilities over 16 weeks. Participants were older (mean age 77 years), 58% were female, over half were ethnic minorities (29% African American, 12% Asian American, 21% Hispanic), and at risk for PrI (mean Braden Scale Risk score = 15.6). Blinded concurrent visual assessments and SEM measurements were obtained at heels weekly. Visual skin damage was categorised as normal, erythema, stage 1 PrI, deep tissue injury (DTI) or stage 2 or greater PrI. PrI incidence was 76%. Off-loading occurred with pillows (76% of residents) rather than heel boots (21%) and often for those with DTI (91%). Subepidermal moisture was measured with a device where higher readings indicate greater moisture (range: 0-70 tissue dielectric constant), with normal skin values significantly different from values in the presence of skin damage. Subepidermal moisture was associated with concurrent damage and damage 1 week later in generalised multinomial logistic models adjusting for age, diabetes and function. Subepidermal moisture detected DTI and differentiated those that resolved, remained and deteriorated over 16 weeks. Subepidermal moisture may be an objective method for detecting PrI.

Cellular mechanisms of skin repair in humans and other mammals

The increased incidence of non-healing skin wounds in developed societies has prompted tremendous research efforts on the complex process known as "wound healing". Unfortunately, the weak relevance of modern wound healing research to human health continues to be a matter of concern. This review summarizes the current knowledge of the cellular mechanisms that mediate wound closure in the skin of humans and laboratory animals. The author highlights the anatomical singularities of human skin vs. the skin of other mammals commonly used for wound healing research (i.e. as mice, rats, rabbits, and pigs), and discusses the roles of stem cells, myofibroblasts, and the matrix environment in the repair process. The majority of this review focuses on reepithelialization and wound closure. Other aspects of wound healing (e.g. inflammation, fibrous healing) are referred to when relevant to the main topic. This review aims at providing the reader with a clear understanding of the similarities and differences that have been reported over the past 100 years between the healing of human wounds and that of other mammals.