Heather R. Kimbriel

Maggot Therapy in "Lower-Extremity Hospice" Wound Care Fewer Amputations and More Antibiotic-Free Days

We sought to assess, in a case-control model, the potential efficacy of maggot debridement therapy in 60 nonambulatory patients (mean +/- SD age, 72.2 +/- 6.8 years) with neuroischemic diabetic foot wounds (University of Texas grade C or D wounds below the malleoli) and peripheral vascular disease. Twenty-seven of these patients (45%) healed during 6 months of review. There was no significant difference in the proportion of patients healing in the maggot debridement therapy versus control group (57% versus 33%). Of patients who healed, time to healing was significantly shorter in the maggot therapy than in the control group (18.5 +/- 4.8 versus 22.4 +/- 4.4 weeks). Approximately one in five patients (22%) underwent a high-level (above-the-foot) amputation. Patients in the control group were three times as likely to undergo amputation (33% versus 10%). Although there was no significant difference in infection prevalence in patients undergoing maggot therapy versus controls (80% versus 60%), there were significantly more antibiotic-free days during follow-up in patients who received maggot therapy (126.8 +/- 30.3 versus 81.9 +/- 42.1 days). Maggot debridement therapy reduces short-term morbidity in nonambulatory patients with diabetic foot wounds.

The impact and outcomes of establishing an integrated interdisciplinary surgical team to care for the diabetic foot

This study aimed to quantify the impact of an integrated diabetic foot surgical service on outcomes and changes in surgical volume and focus.

Diabetic Foot Infections: A Need for Innovative Assessments

Foot wounds are the most common diabetes-related cause of hospitalization and frequently result in amputation. Although generally diagnosed clinically based on signs and symptoms of inflammation, empirical antibiotic treatment should be based on tissue cultures until resolution of infection. Advances in molecular detection over the past decade, including rapid chromogenic agar and real-time polymerase chain reaction, have improved diagnostic capabilities. However, chronic wounds may host biofilm bacteria not adequately detected by current microbiological testing. Enhanced DNA testing is required to identify these pathogens as well as evolving and previously underdiagnosed bacteria. Two options, nucleic acid fluorescent in situ hybridization and rDNA sequencing, are on the horizon for clinical use. Wound biofilms also necessitate more complex clinical management including debridement, augmenting host defenses, suppression of biofilms, and wound closure. Adopting these advances in diagnosis and treatment may help with overall prognosis and reduce health care costs.

Do US veterans wear appropriately sized shoes? The veterans affairs shoe size selection study

Poorly fitting footwear has frequently been cited as an etiologic factor in the pathway to diabetic foot ulceration. However, we are unaware of any reports in the medical literature specifically measuring shoe size versus foot size in this high-risk population. We assessed the prevalence of poorly fitting footwear in individuals with and without diabetic foot ulceration. We evaluated the shoe size of 440 consecutive patients (94.1% male; mean +/- SD age, 67.2 +/- 12.5 years) presenting to an interdisciplinary teaching clinic. Of this population, 58.4% were diagnosed as having diabetes, and 6.8% had active diabetic foot ulceration. Only 25.5% of the patients were wearing appropriately sized shoes. Individuals with diabetic foot ulceration were 5.1 times more likely to have poorly fitting shoes than those without a wound (93.3% versus 73.2%; odds ratio [OR], 5.1; 95% confidence interval [CI], 1.2-21.9; P = .02). This association was also evident when assessing only the 32.3% of the total population with diabetes and loss of protective sensation (93.3% versus 75.0%; OR, 4.8; 95% CI, 1.1-20.9; P = .04). Poorly fitting shoes seem to be more prevalent in people with diabetic foot wounds than in those without wounds with or without peripheral neuropathy. This implies that appropriate meticulous screening for shoe-foot mismatches may be useful in reducing the risk of lower-extremity ulceration.

Novel Use of Platelet-Rich Plasma to Augment Curative Diabetic Foot Surgery

Autologous platelet-rich plasma (PRP) may enhance wound healing through the formation of a platelet plug that provides both hemostasis and the secretion of biologically active proteins, including growth factors such as platelet-derived growth factor, transforming growth factor (TGF)-β, TGF-β2, and epidermal growth factor. The release of these growth factors into the wound may create an environment more conducive to tissue repair and could accelerate postoperative wound healing. To our knowledge, there are no reports of combining the use of PRP with curative diabetic foot surgery. This article provides a summary of the literature regarding PRP and wound healing and presents a case of a 49-year-old man with diabetes and a three-month history of a deep, nonhealing plantar hallux wound in which PRP was combined with a first metatarsophalangeal joint arthroplasty. Through the use of the PRP and bioengineered tissue to supplement curative diabetic foot surgery, the patient healed uneventfully at seven weeks.

Novel use of insulin in continuous-instillation negative pressure wound therapy as "wound chemotherapy".

Negative pressure wound therapy (NPWT) is frequently employed in the treatment of complex wounds. A variety of wound chemotherapeutic agents such as insulin, which acts as a growth factor, may prove helpful in treatment as well. We present a case report in which insulin was used as a chemotherapeutic agent in continuous-instillation NPWT. To our knowledge, this is the first report in the literature describing this method of delivery.

Plantar pressure changes using a novel negative pressure wound therapy technique.

This study evaluated changes in pressure imparted to diabetic foot wounds using a novel negative pressure bridging technique coupled with a robust removable cast walker. Ten patients had plantar pressures assessed with and without a bridged negative pressure dressing on the foot. Off-loading was accomplished with a pressure-relief walker. Plantar pressures were recorded using two pressure-measurement systems. The location and value of peak focal pressure (taken from six midgait steps) were recorded at the site of ulceration. Paired analysis revealed a large difference (mean +/- SD, 74.6% +/- 6.0%) between baseline barefoot pressure and pressure within the pressure-relief walker (mean +/- SD, 939.1 +/- 195.1 versus 235.7 +/- 66.1 kPa). There was a mean +/- SD 9.9% +/- 5.6% higher pressure in the combination device compared with the pressure-relief walker alone (mean +/- SD, 258.0 +/- 69.7 versus 235.7 +/- 66.1 kPa). This difference was only 2% of the initial barefoot pressure imparted to the wound. A modified negative pressure dressing coupled with a robust removable cast walker may not impart undue additional stress to the plantar aspect of the foot and may allow patients to retain some degree of freedom (and a potentially reduced length of hospital stay) while still allowing for the beneficial effects of negative pressure wound therapy and sufficient off-loading.

Cooling the foot to prevent diabetic foot wounds: A proof-of-concept trial

The etiology of neuropathic diabetic foot wounds can be summarized by the following formula: pressure x cycles of repetitive stress = ulceration. The final pathway to ulceration consists of an inflammatory response, leading to tissue breakdown. Mitigation of this response might reduce the risk of ulceration. This proof-of-concept trial evaluates whether simple cooling of the foot can safely reduce the time to thermal equilibrium after activity. After a 15-min brisk walk, the six nondiabetic volunteers enrolled were randomly assigned to receive either air cooling or a 10-min 55 degrees F cool water bath followed by air cooling. The process was then repeated with the intervention reversed, allowing subjects to serve as their own controls. There was a rise in mean +/- SD skin temperature after 15 min of activity versus preactivity levels (87.8 degrees +/- 3.9 degrees versus 79 degrees +/- 2.2 degrees F; P = .0001). Water cooling immediately brought the foot to a point cooler than preactivity levels for all subjects, whereas air cooling required an average of nearly 17 min to do so. Ten minutes of cooling required a mean +/- SD of 26.2 +/- 5.9 min to warm to preactivity levels. No adverse effects resulted from the intervention. We conclude that cooling the foot may be a safe and effective method of reducing inflammation and may serve as a prophylactic or interventional tool to reduce skin breakdown risk.

Use of a Maggot Motility Index to Evaluate Survival of Therapeutic Larvae

Maggot debridement therapy is rapidly increasing in popularity at major diabetic foot and wound care centers worldwide. However, we are unaware of specific guidelines on the short-term storage of larvae. We sought to evaluate differences in maggot motility over time in larvae refrigerated versus those stored at room temperature. We also introduce a simple surrogate method for evaluating maggot vitality that may be useful for in vivo studies if validated in future works. We randomly selected ten larvae from the same shipment at ten different times in 9 days. Larvae were placed on a translucent acetate grid, and their total excursion in 30 sec was measured. This was converted into a Maggot Motility Index. In the refrigerated group, the index remained at or above 40 mm/min for approximately 60 hours from baseline, when there was a significant decrease. This same phenomenon occurred during the first 12 hours in the nonrefrigerated group. There were significant differences in motility between refrigerated and nonrefrigerated larvae immediately after baseline until day 8. Larvae are more practical for repeated clinical use if kept refrigerated between applications.

Feasibility, Safety, and Primary Efficacy of DermaStream A Novel Continuously Streaming Device for Chronic Wounds

Chronic wounds are associated with significant morbidity, mortality, and economic burden. Once a wound has settled into a senescent phase, outside factors must be used to convert that wound back to a more acute phase. Traditional methods, such as surgical debridement or biologic debridement, can cause removal of healthy tissue as well as pain to the patient. Enzymatic debridement has been under much scrutiny lately as popular drugs have been pulled by the Food and Drug Administration. The purpose of this study was to test feasibility, safety, and primary efficacy of 5 control subjects and 10 treatment subjects to the DermaStream system. It is a device that uses a continuously streaming infusion to create a stable, granular wound bed in a relatively short amount of time. The device provides for continuously streaming of therapeutic solutions to the wound while removing exudates by vacuum-assisted drainage throughout the treatment cycle.