Assessment of clinical effectiveness of haemoglobin spray as adjunctive therapy in the treatment of sloughy wounds

Adjunctive topical oxygen therapy in the management of complex diabetes-related wounds: A South African case study series

Diabetic foot ulcers (DFUs) are a prevalent complication of diabetes mellitus and are associated with significant morbidity and mortality. The essential role of oxygen in the treatment of DFUs is documented. Indicated for use on a variety of wound types, topical haemoglobin therapy (Granulox®) is a novel therapeutic technology that binds atmospheric oxygen and improves the availability of oxygen at the wound site. When used as part of the wound management strategy, this therapy helps to reduce inflammation, exudate and slough, and promotes wound healing. In South Africa, health resources, coordinated foot care and podiatry, and data on diabetic foot complications are limited. Twelve patient case studies assessing the impact of adding topical haemoglobin therapy to the management regimes for DFUs and surgical (post-amputation) wounds were undertaken in South Africa. Patients were aged 50-71 years, and all had diabetes mellitus. At baseline, the area of the wounds ranged from 10.2 to 149.6 cm2 with depths ranging from 0.2 to 0.9 cm. Clinical signs of wound infection and high levels of viscous exudate were recorded in all cases. Wound dressings were changed twice weekly and sharp debridement of the wound performed as necessary. The wounds were cleansed and then completely coated with a thin film of Granulox® and dressings applied. Treatment was monitored over periods ranging from 57 to 276 days, during which dressings were changed and Granulox® administered to the wounds, ranging from 16 to 79 times. During the period of evaluation, wound size steadily reduced (by 87.1-100%), the condition of the wound bed tissue and peri-wound skin improved, and clinical signs of wound infection steadily resolved. Wounds significantly improved in two patients, almost healed in six patients, and healed in four patients. All patients reported a reduction in malodour and pain; seven patients were pain-free at the final followup assessment. The overall impression of Granulox® was rated as 'very good' by the clinicians, who considered that Granulox® facilitated an increase in tissue viability, with the promotion of granulation tissue, and stimulated epithelialisation.

A new algorithm for the management of diabetic foot ulcer: recommendations from Central and Eastern Europe

There is wide regional variation in clinical practice and access to treatment for patients with diabetic foot ulcer (DFU) from countries in Central and Eastern Europe (CEE). A treatment algorithm that reflects current treatment practices while providing a common framework may facilitate best practice in DFU management and improve outcomes across the CEE region. Following a series of regional advisory board meetings with experts from Poland, the Czech Republic, Hungary and Croatia, we present consensus recommendations for the management of DFU and outline the key features of a unified algorithm for dissemination and use as a quick tool in clinical practice in CEE. The algorithm should be accessible to specialists as well as non-specialist clinicians and should incorporate: patient screening; checkpoints for assessment and referral; triggers of treatment change; and strategies for infection control, wound bed preparation and offloading. Among adjunctive treatments in DFU, there is a clear role for topical oxygen therapy, which can be used concomitantly with most existing treatment regimens in hard-to-heal wounds following standard of care. Countries from CEE face a number of challenges in the management of DFU. It is hoped that such an algorithm will help standardise the approach to DFU management and overcome some of these challenges. Ultimately, a regionwide treatment algorithm in CEE has the potential to improve clinical outcomes and save limbs.

Use of topical haemoglobin spray in hard-to-heal wound management: a systematic review

OBJECTIVE

To synthesise the best available evidence regarding the effectiveness of using topical haemoglobin spray to promote healing in hard-to-heal wounds in adults.

METHOD

The search strategy of this systematic review was designed to retrieve studies published across CINAHL, Medline, Cochrane Central Register of Controlled Trials, Web of Science, Embase, ERIC, Scopus and Mednar, before January 2020, and published in English. All study participants were aged ≥18 years. This review included randomised controlled trials, case-control studies and observational studies. The studies selected for retrieval were assessed by two independent reviewers for methodological validity prior to inclusion using standardised critical appraisal instruments.

RESULTS

The review included 15 studies. Overall effectiveness was demonstrated for wound closure rates, reductions in wound size, severity of wound pain and patient satisfaction with using a topical haemoglobin spray. The meta-analysis revealed a statistically significant effect of a topical haemoglobin spray in reducing the size of venous leg ulcers (VLU, effect size=0.02; 95% confidence interval: 0.00-0.09; p<0.00001) in adult patients. However, evidence of the effectiveness of using a topical haemoglobin spray in different wound types among adult patients was limited and not high-level, which precludes any strong conclusions.

CONCLUSION

The review provides an evidence-based guide to future priorities for clinical practice. In particular, a topical haemoglobin spray was shown to have a positive impact in reducing VLU size and promoting wound healing.

Shifting the distribution curve for healthcare resource use through topical oxygen therapy for wound healing

The clinical and economic burden associated with hard-to-heal wounds is high and evidence suggests that it continues to increase. Healthcare resources consumed during the provision of wound care can be saved by implementing strategies and actions aimed at promoting wound healing. When these are successful, the frequency distribution curve for time to healing and for the consumption of healthcare resources should 'move to the left' and the extent to which it is 'skewed to the right' would be reduced, resulting in a reduction in the population mean for time to wound healing, and correspondingly, healthcare resources. Not only would this release healthcare resources in the short term, but, if these changes are maintained, would render savings sustainable, thereby contributing to lowering the overall burden of wounds and wound care. In this article, we present evidence that suggests that the adoption of adjunct topical haemoglobin spray can effect these desired changes in the wound healing curve and, due to the nature of the technology, it can be easily and sustainably implemented within relevant whole populations requiring wound care. The ease of adoption and impact is further illustrated by a patient case study.

Systematic review of the efficacy of topical haemoglobin therapy for wound healing

Hypoxia is a common cause of poor wound healing, for which a variety of oxygen therapies have been developed. In order to overcome the limitations of traditional methods of treatment, namely the type of equipment, its setting, safety and cost, local haemoglobin therapy has been developed, although no reviews have so far been published. Here, we systematically review the current evidence to establish the efficacy, scope, adverse reactions, and required precautions of this new form of therapy. A search of the literature was conducted in the PubMed, Embase, Scopus, CENTRAL, CINAHL, and Web of science databases, with 17 studies meeting the eligibility criteria, comprising one animal model study and 16 clinical studies. Local haemoglobin therapy is able to safely and effectively promote the healing of a variety of wounds, especially those that are chronic and non-healing. However, premature discontinuation of this treatment can result in impediment to wound healing and even deterioration of the wound. The distinct benefit of the elimination of slough and relief of pain suggests that this technique may represent a new generation of debridement technology. Furthermore, its ease of use and convenience enables patient self-management, thereby greatly reducing health care costs.

Cost-effectiveness of adjunct haemoglobin spray in the treatment of hard-to-heal wounds in a UK NHS primary care setting

OBJECTIVE

To evaluate the cost-effectiveness of topical haemoglobin spray as adjunct therapy in the treatment of hard-to-heal wounds within a UK National Health Service (NHS) community setting.

METHOD

In a previously published comparative clinical evaluation, 50 consecutive patients treated with topical haemoglobin spray, as adjunct to standard care and followed up over 26 weeks, were compared with 50 consecutive retrospective controls from the same clinic treated with the same standard care protocol in the year prior to the introduction of adjunct topical haemoglobin spray. A de novo cost-effectiveness and break-even analysis were performed, using data from the previously published clinical evaluation, for all patients (intent-to-treat) and for patients with complete follow-up using a micro-costing approach and considering only wound care dressing costs.

RESULTS

At 26 weeks, the total cost of dressings for all patients in the intervention group was £6953 with 874 cumulative weeks healed, compared with £9547 with 278 cumulative weeks healed for all patients in the control group. The incremental cost-effectiveness ratio (ICER), the incremental cost per additional week healed with adjunct topical haemoglobin spray, is therefore negative (dominant). Total treatment costs per week were lower from week six onwards, with break-even estimated to be at week 10.2. When considering only patients with complete follow-up, the results were similarly dominant, with a mean 10.9 more weeks healed, a mean dressing cost saving per patient of £81.83 by week 26 (-37%). Cost savings were realised from week five, and a break-even was estimated to occur at week 8.0.

CONCLUSION

Topical haemoglobin spray has the potential to restore the healing process, reduce healing times and reduce dressing costs in a NHS community setting, within a few weeks of adoption.

Topical application of haemoglobin: a safety study

OBJECTIVE

Ischaemia is one of the biggest problems in wound healing. It causes chronic wounds and also prevents normal wound healing because the tissue is oxygen deprived. Most oxygen-supplying therapies are only feasible in a clinical setting, but topical haemoglobin applications, such as Granulox, can be used in a non-clinical setting. For home application, the haemoglobin solution is sprayed topically onto the wound using a pressurised ready-to-use device with a bag-on-valve system. Although this system does not mix product and propellant, the risk of product inhalation by the patient, user or bystanders has to be minimised. This safety study aimed to determine particle size and product concentration in the surroundings after application to determine if there is a risk that product particles enter the respiratory tract.

METHODS

Measurements were performed using a laser scattered light photometer and a Scanning Mobility Particle Sizer (SMPS)-Spectrometer at different distances from the measuring devices to determine the inhalation risk for a possible user, patient and bystander. At all measuring points the amount of particles, their size and the formation of dust were measured.

RESULTS

No nanoparticles or dust were created during the application of the haemoglobin spray. The concentrations of the measured particles are below the allowed limits defined by Austrian law.

CONCLUSION

There is no risk of inhaling nanoparticles or being exposed to harmful concentrations of larger particles of the tested product. All the product's ingredients can be degraded and excreted by the human body through natural pathways.

Hemoglobin spray as adjunct therapy in complex wounds: Meta-analysis versus standard care alone in pooled data by wound type across three retrospective cohort controlled evaluations

Objectives:

Low tissue oxygenation is a predictor of healing outcomes in complex wounds. Adjunct hemoglobin to aid oxygen diffusion has been demonstrated to achieve superior healing outcomes; however, the relative healing benefit across different wound types and evaluations has not yet been estimated. This article does this for the first time.

Methods:

Data were pooled from previously published real world controlled evaluations, three retrospective cohort controlled studies of a variety of wounds within standard care across hospital and primary care in the North of England in patients with diabetic foot ulcers (n = 40), chronic wounds (n = 100), and sloughy wounds (n = 200). Wounds were equally distributed between adjunct hemoglobin and control and the hemoglobin spray was used as per instructions for use and applied twice weekly, mostly for the duration of the wounds in all three evaluations. Wound healing over 26 weeks was the primary outcome in each of the evaluations, with additional healing and quality of life indicators including pain, wound size, slough coverage, wound exudate levels, adverse events, and dressing regimen used, over time. Each wound type with 10 or more patients in both the standard care alone and adjunctive hemoglobin groups (n = 257/73% of patients) was evaluated.

Results:

Cox proportional hazards log-rank regressions demonstrated significantly higher weekly chance of healing in each wound type (β, 95% range, sample, p): trauma 1.55 (1.23–1.96, n = 110, p < 0.001), diabetic foot ulcers 2.39 (1.52–3.75, n = 60, p = 0.01), venous leg ulcers 4.98 (1.69–14.7, n = 33, p = 0.04), burns 1.82 (1.11–2.99, n = 30, p = 0.02), and post-surgical wounds 2.75 (1.53–4.96, n = 24, p = 0.001). Results on additional healing indicators were consistent with the main findings. Notably, controlling for ischemia in diabetic foot ulcers resulted in an increased β of 5.68 (2.33–13.86, n = 29, p < 0.001).

Conclusion:

Adjunct hemoglobin spray, when implemented within standard care, is likely to achieve substantial healing benefits to patients, in particular for diabetic foot ulcers, venous leg ulcers, and post-surgical wounds.