USA slipping behind Asia/Pacific markets in wound care sales

We present data from our 2016 to 2026 forecast of the global market for wound management products (report #S254, published March 2018). 


At a glimpse, you can see the overall trend in global wound management, including the relative size of each market. (The four regional sales charts are shown on the same scale to illustrate this.)  Most notably, the USA dominance of this global market is fading, as aggregate Asia/Pacific sales of all wound products will eclipse USA sales within the forecast period.

 

 

 

 

 

 


Source: MedMarket Diligence, LLC; Report #S254.

Looking at just the aggregate of all wound product types, Asia/Pacific relative sales are squeezing out shares in every other region.Source: MedMarket Diligence, LLC; Report #S254.

When we then look specifically at the USA versus Asia/Pacific, it illustrates that by 2020, Asia/Pacific’s sales of wound management products will eclipse those of the U.S., making it the largest regional wound management market.

Source: MedMarket Diligence, LLC; Report #S254.

Changes in Fortunes for Wound Management Products

Over the 2017 to 2026 period, the compound annual growth rate for the entire wound management market will approach 6%, a respectable rate of growth for an established market, though not quite high enough to encourage investment in the market as a whole.

Of course, the total wound market is comprised of a number of VERY large, slow-growing segments, like traditional adhesive dressings, gauze dressings, and non-adherent dressings, which have annual sales at $3.8 billion, $3.2 billion, and $1.3 billion, respectively.

The large volume, slow growth of the aggregate masks growth in the following segments:

  • Bioengineered skin and skin substitutes
  • Alginates
  • Foam dressings
  • Growth factors

These wound care segments have had, and will continue to have, annual growth rates at or near double-digit through 2026.

The end result of variable growth rates is that the 2026 Wound Care Market (worldwide), by comparison to 2017, will show the following changes (up/down) in each segment’s share of the total market.

Source: MedMarket Diligence, LLC; Report #S254 (publishing Mar. 2018).

Bioengineered skin, alginates lead wound market growth

Big revenues, as in $ billions, are turned over every year in traditional wound dressings and gauze, while emerging technologies designed to have far more impact on wound management are driving the fastest percentage revenue growth. Data from “Wound Management to 2026” (report S254) shows the size-to-growth distribution of wound product revenue streams over the 2017 to 2026 period.

Source: MedMarket Diligence, LLC; Report #S254.

The future of medicine in 2037

In the post below from 2016, we wrote of what we can expect for medicine 20 years into the future. We review and revise it anew here.

An important determinant of “where medicine will be” in 2035 is the set of dynamics and forces behind healthcare delivery systems, including primarily the payment method, especially regarding reimbursement. It is clear that some form of reform in healthcare will result in a consolidation of the infrastructure paying for and managing patient populations. The infrastructure is bloated and expensive, unnecessarily adding to costs that neither the federal government nor individuals can sustain. This is not to say that I predict movement to a single payer system — that is just one perceived solution to the problem. There are far too many costs in healthcare that offer no benefits in terms of quality; indeed, such costs are a true impediment to quality. Funds that go to infrastructure (insurance companies and other intermediaries) and the demands they put on healthcare delivery work directly against quality of care. So, in the U.S., whether the Affordable Care Act (“Obamacare”) persists (most likely) or is replaced with a single payer system, state administered healthcare (exchanges) or some other as-yet-unidentified form, there will be change in how healthcare is delivered from a cost/management perspective.  -[Editor’s note: After multiple attempts by the GOP to “repeal and replace”, the strengths of Obamacare have outweighed its weaknesses in the minds of voters who have thus voiced their opinions to their representatives, many seeking reelection in 2018.]

From the clinical practice and technology side, there will be enormous changes to healthcare. Here are examples of what I see from tracking trends in clinical practice and medical technology development:

  • Cancer 5 year survival rates will, for many cancers, be well over 90%. Cancer will largely be transformed in most cases to chronic disease that can be effectively managed by surgery, immunology, chemotherapy and other interventions. Cancer and genomics, in particular, has been a lucrative study (see The Cancer Genome Atlas). Immunotherapy developments are also expected to be part of many oncology solutions. Cancer has been a tenacious foe, and remains one we will be fighting for a long time, but the fight will have changed from virtually incapacitating the patient to following protocols that keep cancer in check, if not cure/prevent it.
    [Editor’s note: Immunology has surged in a wide range of cancer-related research yielding new weapons to cure cancer or render it to routine clinical management.]
  • Diabetes Type 1 (juvenile onset) will be managed in most patients by an “artificial pancreas”, a closed loop glucometer and insulin pump that will self-regulate blood glucose levels. OR, stem cell or other cell therapies may well achieve success in restoring normal insulin production and glucose metabolism in Type 1 patients. The odds are better that a practical, affordable artificial pancreas will developed than stem or other cell therapy, but both technologies are moving aggressively and will gain dramatic successes within 20 years.

Developments in the field of the “artificial pancreas” have recently gathered considerable pace, such that, by 2035, type 1 blood glucose management may be no more onerous than a house thermostat due to the sophistication and ease-of-use made possible with the closed loop, biofeedback capabilities of the integrated glucometer, insulin pump and the algorithms that drive it, but that will not be the end of the development of better options for type 1 diabetics. Cell therapy for type 1 diabetes, which may be readily achieved by one or more of a wide variety of cellular approaches and product forms (including cell/device hybrids) may well have progressed by 2035 to become another viable alternative for type 1 diabetics. [Editor’s note: Our view of this stands, as artificial pancreases are maturing in development and reaching markets. Cell therapy still offers the most “cure-like” result, which is likely to happen within the next 20 years.]

  • Diabetes Type 2 (adult onset) will be a significant problem, governed as it is by different dynamics than Type 1. A large body of evidence will exist that shows dramatically reduced incidence of Type 2 associated with obesity management (gastric bypass, satiety drugs, etc.) that will mitigate the growing prevalence of Type 2, but research into pharmacologic or other therapies may at best achieve only modest advances. The problem will reside in the complexity of different Type 2 manifestation, the late onset of the condition in patients who are resistant to the necessary changes in lifestyle and the global epidemic that will challenge dissemination of new technologies and clinical practices to third world populations.

Despite increasing levels of attention being raised to the burden of type 2 worldwide, including all its sequellae (vascular, retinal, kidney and other diseases), the pace of growth globally in type 2 is still such that it will represent a problem and target for pharma, biotech, medical device, and other disciplines. [Editor’s note: the burden of Type 2 on people, families, communities, and governments globally should motivate policy, legislation, and other action, but global initiatives have a long way to travel.]

  • Cell therapy and tissue engineering will offer an enormous number of solutions for conditions currently treated inadequately, if at all. Below is an illustration of the range of applications currently available or in development, a list that will expand (along with successes in each) over the next 20 years.

    Cell therapy will have deeply penetrated virtually every medical specialty by 2035. Most advanced will be those that target less complex tissues: bone, muscle, skin, and select internal organ tissues (e.g., bioengineered bladder, others). However, development will have also followed the money. Currently, development and use of conventional technologies in areas like cardiology, vascular, and neurology entails high expenditure that creates enormous investment incentive that will drive steady development of cell therapy and tissue engineering over the next 20 years, with the goal of better, more long-term and/or less costly solutions.
  • Gene therapy will be an option for a majority of genetically-based diseases (especially inherited diseases) and will offer clinical options for non-inherited conditions. Advances in the analysis of inheritance and expression of genes will also enable advanced interventions to either ameliorate or actually preempt the onset of genetic disease.

    As the human genome is the engineering plans for the human body, it is a potential mother lode for the future of medicine, but it remains a complex set of plans to elucidate and exploit for the development of therapies. While genetically-based diseases may readily be addressed by gene therapies in 2035, the host of other diseases that do not have obvious genetic components will resist giving up easy gene therapy solutions. Then again, within 20 years a number of reasonable advances in understanding and intervention could open the gate to widespread “gene therapy” (in some sense) for a breadth of diseases and conditions. [Editor’s note: CRISPR and other gene-editing techniques have accelerated the pace at which practical and affordable gene-therapies will reach the market.]
  • Drug development will be dramatically more sophisticated, reducing the development time and cost while resulting in drugs that are far more clinically effective (and less prone to side effects). [Editor’s note: We are revising our optimism about drug development being more sophisticated and streamlined. To a measurable degree, “distributed processing systems” have proven far more exciting in principle than practice, since results — marketable drugs derived this way — have been scant. We remain optimistic as a result of the rapid emergence of artificial intelligence (AI) and deep learning, which have have very credible promise to impact swaths of industry, especially in medicine.]
    This arises from drug candidates being evaluated via distributed processing systems (or quantum computer systems) that can predict efficacy and side effect without need of expensive and exhaustive animal or human testing.The development of effective drugs will have been accelerated by both modeling systems and increases in our understanding of disease and trauma, including pharmacogenomics to predict drug response. It may not as readily follow that the costs will be reduced, something that may only happen as a result of policy decisions.

  • Most surgical procedures will achieve the ability to be virtually non-invasive. Natural orifice transluminal endoscopic surgery (NOTES) will enable highly sophisticated surgery without ever making an abdominal or other (external) incision. Technologies like “gamma knife” and similar will have the ability to destroy tumors or ablate pathological tissue via completely external, energy-based systems. [Editor’s note: In the late 1980s, laparoscopy revolutionized surgery for its less invasiveness. Now, NOTES procedures and external energy technologies (e.g., gamma knife) have now proven to be about as minimally invasive as medical devices can be. To be even less invasive will require development of drugs (including biotechs) that succeed as therapeutic alternatives to any kind of surgery.]

    By 2035, technologies such as these will measurably reduce inpatient stays, on a per capita basis, since a significant reason for overnight stays is the trauma requiring recovery, and eliminating trauma is a major goal and advantage of minimally invasive technologies (e.g., especially the NOTES technology platform). A wide range of other technologies (e.g., gamma knife, minimally invasive surgery/intervention, etc.) across multiple categories (device, biotech, pharma) will also have emerged and succeeded in the market by producing therapeutic benefit while minimizing or eliminating collateral damage.

  • Information technology will radically improve patient management. Very sophisticated electronic patient records will dramatically improve patient care via reduction of contraindications, predictive systems to proactively manage disease and disease risk, and greatly improve the decision-making of physicians tasked with diagnosing and treating patients.There are few technical hurdles to the advancement of information technology in medicine, but even in 2035, infotech is very likely to still be facing real hurdles in its use as a result of the reluctance in healthcare to give up legacy systems and the inertia against change, despite the benefits. [Editor’s note: Before AI and other systems will truly have an impact, IT and its policy for healthcare in the next 10 years will solve the problem of health data residing inertly behind walls that hinder efficient use of the rich, patient-specific knowledge that physicians and healthcare systems might use to improve the quality and cost of care.]
  • Personalized medicine. Perfect matches between a condition and its treatment are the goal of personalized medicine, since patient-to-patient variation can reduce the efficacy of off-the-shelf treatment. The thinking behind gender-specific joint replacement has led to custom-printed 3D implants. The use of personalized medicine will also be manifested by testing to reveal potential emerging diseases or conditions, whose symptoms may be ameliorated or prevented by intervention before onset.
  • Systems biology will underlie the biology of most future medical advances in the next 20 years. Systems biology is a discipline focused on an integrated understanding of cell biology, physiology, genetics, chemistry, and a wide range of other individual medical and scientific disciplines. It represents an implicit recognition of an organism as an embodiment of multiple, interdependent organ systems and its processes, such that both pathology and wellness are understood from the perspective of the sum total of both the problem and the impact of possible solutions.This orientation will be intrinsic to the development of medical technologies, and will increasingly be represented by clinical trials that throw a much wider and longer-term net around relevant data, staff expertise encompassing more medical/scientific disciplines, and unforeseen solutions that present themselves as a result of this approach.Other technologies being developed aggressively now will have an impact over the next twenty years, including medical/surgical robots (or even biobots), neurotechnologies to diagnose, monitor, and treat a wide range of conditions (e.g., spinal cord injury, Alzheimer’s, Parkinson’s etc.).

The breadth and depth of advances in medicine over the next 20 years will be extraordinary, since many doors have been recently opened as a result of advances in genetics, cell biology, materials science, systems biology and others — with the collective advances further stimulating both learning and new product development. 


See Reports:

Report #290, “Worldwide Markets for Medical and Surgical Sealants, Glues, and Hemostats, 2015-2022.”

Report #S254, “Wound Management to 2026.”

Naturally sticky: Biologically-based medical glues dominate

Medical glues are either biologically-based, cyanoacrylate, or other synthetic. The bulk of global sales of medical glues are biologically-based, (includes fibrin, thrombogen, and others), cyanoacrylate-based glues, and other synthetic glues.

Cyanoacrylate-based glues, include those from Ethicon, Adhezion Biomedical, B. Braun, Meyer-Haake, and others. Cyanoacrylates provide strong adhesion, but biologically-based glues have found more applications, both topically and internally. “Other” glues are of a variety of synthetic types; these glues have yet to gain more than 4% share globally.

Below is illustrated the growth of biologically-based glues by region, showing that most growth in this segment will be from Asia/Pacific markets, which are consistently demonstrating higher growth than in western markets.

Global Markets for Biologically-Based Medical Glues, 2015-2022, USD MillionsSource: MedMarket Diligence, LLC; Report #S290. (Order online)

 

What’s next in sealants, glue, hemostats…and why?

From July 2016 published Report #S290.

Here are six key trends we see in the global market next in surgical sealants, glues, and hemostats:

  1. Aggressive development of products (including by universities, startups, established competitors), regulatory approvals, and new product introductions continues in the U.S., Europe, and Asia/Pacific (mostly Japan, Korea) to satisfy the growing volume of surgical procedures globally.
  2. Rapid adoption of sealants, glues, hemostats in China will drive much of the global market for these products, but other nations in the region are also big consumers, with more of the potential caseload already tapped than the rising economic China giant. Japan is a big developer and user of wound product consumer. Per capital demand is also higher in some countries like Japan.
  3. Flattening markets in the U.S. and Europe (where home-based manufacturers are looking more at emerging markets), with Europe in particular focused intently on lowering healthcare costs.
  4. The M&A, and deal-making that has taken place over the past few years (Bristol-Myers Squibb, The Medicines Company, Cohera Medical, Medafor, CR Bard, Tenaxis, Mallinckrodt, Xcede Technologies, etc.) will continue as market penetration turns to consolidation.
  5. Growing development on two fronts: (1) clinical specialty and/or application specific product formulation, and (2) all purpose products that provide faster sealing, hemostasis, or closure for general wound applications for internal and external use.
  6. Bioglues already hold the lead in global medical glue sales, and more are being developed, but there are also numerous biologically-inspired, though not -derived, glues in the starting blocks that will displace bioglue shares. Nanotech also has its tiny fingers in this pie, as well.

See Report #S290, “Worldwide Sealants, Glues, and Hemostats Markets, 2015-2022”.

Bioengineered skin and skin substitutes in wound management

Bioengineered skin was developed because of the need to cover extensive burn injuries in patients who no longer had enough skin for grafting. Not so long ago, a patient with third degree burns over 50% of his body surface usually died from his injuries. That is no longer the case. Today, even someone with 90% total body surface area burn has a good chance of surviving. With the array of bioengineered skin and skin substitutes available today, such products are also finding use for chronic wounds, in order to prevent infection, speed healing and provide improved cosmetic results.

Skin used in wound care may be autograft (from the patient’s own body, as is often the case with burn patients), allograft (cadaver skin), xenogeneic (from animals such as pigs or cows), or a combination of these. Bioengineered skin substitutes are synthetic, although they, too, may be combined with other products. It consists of an outer epidermal layer and (depending on the product) a dermal layer, which are embedded into an acellular support matrix. This product may be autogenic, or from other sources. Currently most commercial bioengineered skin is sheets of cells derived from neonatal allogenic foreskin. This source is chosen for several reasons: because the cells come from healthy newborns undergoing circumcision, and therefore the tissue would have been discarded anyway; foreskin tissue is high in epidermal keratinocyte stem cells, which grow vigorously; and because allergic reactions to this tissue is uncommon.

Bioengineered skin and skin substitutes are on the market and in development by LifeCell (Acelity), Organogenesis, Smith & Nephew, Organogenesis, Vericel Corporation (formerly Aastrom Biosciences), Mölnlycke Health Care, Integra LifeSciences, Smith & Nephew, Stratatech Corporation, A-Skin, University Children’s Hospital, Zurich; EuroSkinGraft.

The market may become more crowded as growth in the adoption of these products draws more competitors. Bioengineered skin and skin substitutes will drive more revenue than any other segment of the broader wound management market.

Growth in Advanced Wound Market Segments, 2014 to 2024

Competitors’ positions in bioengineered skin are variable based on their geographic presence. See shares in the U.S., the UK, and Germany for bioengineered skin & skin substitutes.

 

Source: MedMarket Diligence, LLC; Report #S251, “Wound Management to 2024.”

 

Source: MedMarket Diligence, LLC; Report #S251, “Wound Management to 2024.”

Source: MedMarket Diligence, LLC; Report #S251, “Wound Management to 2024.”

 

Medtech fundings for March 2017

Medtech fundings for March 2017 totaled over $2 billion, led by the $1.2 billion raise by ConvaTec, the $59 million IPO of Symetics, the $50 million Series C funding of Moximed, the $45 million funding of Corindus, and the $40 million funding round of VertiFlex.

The complete list of fundings in medtech for March 2017 are shown at link. Below are the top fundings for the month.

Source: Compiled by MedMarket Diligence, LLC

For a historical list of fundings by month since 2009, see link.

Add tick cement to the list of natural adhesives pursued for medical applications

In past posts, we have reported on multiple naturally-occurring substances or methods for strong adhesion that are being investigated for their potential to be exploited for medical or surgical adhesion. These include adhesives from remora, mussels, geckos, crab shells, barnacles, Australian burrowing frogs, spider webs, porcupine quills, sandcastle worms, etc.

Researchers from MedUni Vienna and Vienna University of Technology are now investigating 300 different ticks for the “cement” used by the parasites to attach to hosts. The goal is to study the composition of the natural tick “dowel” used by the mouthparts of ticks and determine how it might serve as a template for new tissue adhesives.

The Vienna research also notes other natural adhesives are similarly being investigated for medical and surgical use:

Other potential “adhesive donors” are sea cucumbers, which shoot sticky threads out of their sac; species of salamander, which secrete extremely fast-drying adhesive out of skin glands, if attacked; or insect larvae, which produce tentacles or crabs, which can remain firmly “stuck,” even under water.

The incentive for studying natural adhesives is that they have been driven by evolution to provide strong adhesion without toxicity in various wet or dry conditions that are challenging for existing synthetic or existing natural glues (e.g., fibrin glues, cyanoacrylates, etc.). Surgical glues currently in use have some limitation arising from lesser strength, ease of use, toxicity, and other shortcomings. New glues will gain wider adoption, capturing procedure volume used with sutures, clips and other closure methods, particularly in internal use, if they are stronger and/or provide tighter seals (without needing to be combined with sutures on the same incision/wound) and do not cause the toxicity that some high strength medical glues do (e.g., synthetics like cyanoacrylates; “super glues”). The biologically-derived glues (or the surfaces structures of gecko feet) avoid the toxicities of synthetics and have often proven to have very high tensile strength. (The fast-curing cement used by barnacles has been shown to have a remarkable tensile strength of 5,000 pounds per square inch.)

Edit: See also, Biomimetic Glue, based on shellfish natural adhesive.


MedMarket Diligence tracks the technologies, clinical practices, companies, and markets associated with medical and surgical sealants and glues, with the most recent coverage in, “Worldwide Markets for Medical and Surgical Sealants, Glues, and Hemostats, 2015-2022,” (report #S290).

Factors Affecting Wound Healing

Coming March 2018:  Worldwide Wound Management, Forecast to 2026 more


The below is excerpted from Wound Management Report #S251

A delicate physiological balance must be maintained during the healing process to ensure timely repair or regeneration of damaged tissue. Wounds may fail to heal or have a greatly increased healing time when unfavorable conditions are allowed to persist. An optimal environment must be provided to support the essential biochemical and cellular activities required for efficient wound healing and to remove or protect the wound from factors that impede the healing process.

Factors affecting wound healing may be considered in one of two categories depending on their source. Extrinsic factors impinge on the patient from the external environment, whereas intrinsic factors directly affect the performance of bodily functions through the patient’s own physiology or condition.

Wound bed preparation (WBP) is essential for the support of efficient and effective healing, especially when advanced wound care products are to be used. WBP involves removing localized barriers to healing, such as exudate, dead tissue or infected tissue.

Wound Bed Preparation: the TIME and DIMES acronyms

WBP involves debridement, reduction and neutralization of the bioburden and management of exudate from the wound. The TIME acronym provides a systematic way to manage wounds by looking at each stage of wound healing. The goal is to have the best, thoroughly-vascularized wound bed possible.

TIME stands for:

  • T: Tissue, non-viable or deficient.

The wound care professional should look for non-viable tissue, which includes necrotic tissue, tissue which has sloughed off, or non-viable tendon or bone.

  • I: Infection or Inflammation

Examine the wound for infection, inflammation or other signs of infection. Are there clinical signs that there may be a problem with bacterial bioburden?

  • M: Moisture Balance

Is the wound too dry, or does it have excess exudate?

What is the objective of topical therapy: absorption or drainage?

  • E: Edge of wound—non-advancing or undermined

Examine the edges of the wound. Are the edges undermined, or is the epidermis failing to migrate across the granulation tissue?

The DIMES acronym is very similar to TIME:

  • Debridement (autolytic)

For wounds with the ability to heal, adequate and repeated debridement is an important first step in removing necrotic tissue. Debridement may also help healing by removing both senescent cells that are no longer capable of normal cellular activities and biofilms that may be shielding bacterial colonies.

  • Infection/Inflammation

The level of bacterial damage may include contamination (organisms present), colonization (organisms present which may cause surface damage if critically colonized) or infection. Treatment needs to make a match between the individual patient’s wound and the appropriate product.

  • Moisture balance

Clinicians need to create a careful balance in the wound such that the environment is neither too wet nor too dry. The environment itself will change as the wound heals.

  • Edge/Environment

The clinician should carefully examine and monitor the wound edge. If the wound edge is not migrating after appropriate wound bed preparation, and if healing appears to be stalled, then more advanced wound care therapies should be considered.

  • Supportive Products and Services

There are additional products which support wound healing yet don’t fall into one of these steps. For example, proper nutritional support is important to achieving the goal of a fully healed wound.

Extrinsic Factors

Extrinsic factors affecting wound healing include:

  • Mechanical stress
  • Debris
  • Temperature
  • Desiccation and maceration
  • Infection
  • Chemical stress
  • Medications
  • Other factors such as alcohol abuse, smoking, and radiation therapy

Mechanical Stress

Mechanical stress factors include pressure, shear, and friction. Pressure can result from immobility, such as experienced by a bed- or chair-bound patient, or local pressures generated by a cast or poorly fitting shoe on a diabetic foot. When pressure is applied to an area for sufficient time and duration, blood flow to the area is compromised and healing cannot take place. Shear forces may occlude blood vessels, and disrupt or damage granulation tissue. Friction wears away newly formed epithelium or granulation tissue and may return the wound to the inflammatory phase.

Debris

Debris, such as necrotic tissue or foreign material, must be removed from the wound site in order to allow the wound to progress from the inflammatory stage to the proliferative stage of healing. Necrotic debris includes eschar and slough. The removal of necrotic tissue is called debridement and may be accomplished by mechanical, chemical, autolytic, or surgical means. Foreign material may include sutures, dressing residues, fibers shed by dressings, and foreign material which were introduced during the wounding process, such as dirt or glass.

Temperature

Temperature controls the rate of chemical and enzymatic processes occurring within the wound and the metabolism of cells and tissue engaged in the repair process. Frequent dressing changes or wound cleansing with room temperature solutions may reduce wound temperature, often requiring several hours for recovery to physiological levels. Thus, wound dressings that promote a “cooling” effect, while they may help to decrease pain, may not support wound repair.

Desiccation and Maceration

Desiccation of the wound surface removes the physiological fluids that support wound healing activity. Dry wounds are more painful, itchy, and produce scab material in an attempt to reduce fluid loss. Cell proliferation, leukocyte activity, wound contraction, and revascularization are all reduced in a dry environment. Epithelialization is drastically slowed in the presence of scab tissue that forces epithelial cells to burrow rather than freely migrate over granulation tissue. Advanced wound dressings provide protection against desiccation.

Maceration resulting from prolonged exposure to moisture may occur from incontinence, sweat accumulation, or excess exudates. Maceration can lead to enlargement of the wound, increased susceptibility to mechanical forces, and infection. Advanced wound products are designed to remove sources of moisture, manage wound exudates, and protect skin at the edges of the wound from exposure to exudates, incontinence, or perspiration.

Infection

Infection at the wound site will ensure that the healing process remains in the inflammatory phase. Pathogenic microbes in the wound compete with macrophages and fibroblasts for limited resources and may cause further necrosis in the wound bed. Serious wound infection can lead to sepsis and death. While all ulcers are considered contaminated, the diagnosis of infection is made when the wound culture demonstrates bacterial counts in excess of 105 microorganisms per gram of tissue. The clinical signs of wound infection are erythema, heat, local swelling, and pain.

Chemical Stress

Chemical stress is often applied to the wound through the use of antiseptics and cleansing agents. Routine, prolonged use of iodine, peroxide, chlorhexidine, alcohol, and acetic acid has been shown to damage cells and tissue involved in wound repair. Their use is now primarily limited to those wounds and circumstances when infection risk is high. The use of such products is rapidly discontinued in favor of using less cytotoxic agents, such as saline and nonionic surfactants.

Medication

Medication may have significant effects on the phases of wound healing. Anti-inflammatory drugs such as steroids and non-steroidal anti-inflammatory drugs may reduce the inflammatory response necessary to prepare the wound bed for granulation. Chemotherapeutic agents affect the function of normal cells as well as their target tumor tissue; their effects include reduction in the inflammatory response, suppression of protein synthesis, and inhibition of cell reproduction. Immunosuppressive drugs reduce WBC counts, reducing inflammatory activities and increasing the risk of wound infection.

Other Extrinsic Factors

Other extrinsic factors that may affect wound healing include alcohol abuse, smoking, and radiation therapy. Alcohol abuse and smoking interfere with body’s defense system, and side effects from radiation treatments include specific disruptions to the immune system, including suppression of leukocyte production that increases the risk of infection in ulcers. Radiation for treatment of cancer causes secondary complications to the skin and underlying tissue. Early signs of radiation side effects include acute inflammation, exudation, and scabbing. Later signs, which may appear four to six months after radiation, include woody, fibrous, and edematous skin. Advanced radiated skin appearances can include avascular tissue and ulcerations in the circumscribed area of the original radiation. The radiated wound may not become evident until as long as 10-20 years after the end of therapy.

Intrinsic Factors

Intrinsic factors that directly affect the performance of healing are:

  • Health status
  • Age factors
  • Body build
  • Nutritional status

Health Status

Chronic diseases, such as circulatory conditions, anemias and autoimmune diseases, influence the healing process as a result of their influence on a number of bodily functions. Illnesses that cause the most significant problems include diabetes, chronic obstructive pulmonary disease (COPD), arteriosclerosis, peripheral vascular disease (PVD), heart disease, and any conditions leading to hypotension, hypovolemia, edema, and anemia. While chronic diseases are more frequent in the elderly, wound healing will be delayed in any patient with a pre-existing underlying illness.

Chronic circulatory diseases which reduce blood flow, such as arterial or venous insufficiency, lower the amount of oxygen available for normal tissue activity and replacement. Anemias such as sickle-cell anemia result in reduced delivery of oxygen to tissues and decreased ability to support wound healing.

Normal immune function is required during the inflammatory phase by providing the WBCs (white blood cells) that orchestrate or coordinate the normal sequence of events in wound healing. Autoimmune diseases such as lupus and rheumatoid arthritis interfere with normal collagen deposition, and impair granulation.

Diabetes is associated with delayed cellular response to injury, compromised cellular function at the site of injury, defects in collagen synthesis, and reduced wound tensile strength after healing. Diabetes-related peripheral neuropathy (DPN), which reduces the ability to feel pressure or pain, contributes to a tendency to ignore pressure points and avoid pressure relief strategies.

Acquired Immune Deficiency Syndrome

Patients with acquired immunodeficiency syndrome (AIDS) have significant impact on the wound healing market as their numbers rise and their average life expectancy increases. Patients in the latter stages of the disease experience drastic reductions in mobility, activity, and nutritional status, placing them at high risk for the development of pressure ulcers. Minor scrapes or abrasions are at high risk for infection and may progress to full-thickness wounds requiring antibiotic therapy and aggressive wound management. Skin tumors, such as Kaposi’s sarcoma, lead to surgical incisions closed by secondary intention requiring the use of appropriate dressings.

The skin of AIDS patients becomes drier as the syndrome progresses. As the CD4+ T cell count falls below 400/mm3, pruritus increases and erythematous patches appear on the skin, progressing to ichthyosis and appearing as large polygonal scales, especially on the lower limbs. Histological changes include hyperkeratosis and thinning of the granular layer of the epidermis. As skin becomes more fragile, care must be exercised in the selection of tapes and adhesive dressings to avoid skin stripping and skin tears.

Age Factors

Observable changes in wound healing in the elderly include increased time to heal and the fragile structure of healed wounds. Delays are speculated to be the result of a general slowing of metabolism and structural changes in the skin of elderly people. Structural changes include a flattening of the dermal-epidermal junction that often leads to skin tears, reduced quality and quantity of collagen, reduced padding over bony prominences, and reduction in the intensity of the immune response.

Body Build

Body build can affect the delivery and availability of oxygen and nutrients at the wound site. Underweight individuals may lack the necessary energy and protein reserves to provide sufficient raw materials for proliferative wound healing. Bony prominences lack padding and become readily susceptible to pressure due to the reduced blood supply of wounds associated with bony prominences. Poor nutritional habits and reduced mobility of overweight individuals lead to increased risk of wound dehiscence, hernia formation, and infection.

Nutritional Status

Healing wounds, especially full-thickness wounds, require an adequate supply of nutrients. Wounds require calories, fats, proteins, vitamins and minerals, and adequate fluid intake. Calories provide energy for all cellular activity, and when in short supply in the diet, the body will utilize stored fat and protein. The metabolism of these stored substances causes a reduction in weight and changes in pressure distribution through reduction of adipose and muscle padding. Sufficient dietary calories maintain padding and ensure that dietary protein and fats are available for use in wound healing. In addition, adequate levels of protein are necessary for repair and replacement of tissue. Increased protein intake is particularly important for wounds where there is significant tissue loss requiring the production of large amounts of connective tissue. Protein deficiencies have been associated with poor revascularization, decreased fibroblast proliferation, reduced collagen formation, and immune system deficiencies.

Reduced availability of vitamins, minerals, and trace elements will also affect wound healing. Vitamin C is required for collagen synthesis, fibroblast functions, and the immune response. Vitamin A aids macrophage mobility and epithelialization. Vitamin B complex is necessary for the formation of antibodies and WBCs, and Vitamin B or thiamine maintains metabolic pathways that generate energy required for cell reproduction and migration during granulation and epithelialization. Iron is required for the synthesis of hemoglobin, which carries oxygen to the tissues, and copper and zinc play a role in collagen synthesis and epithelialization.

Adequate nutrition is an often-overlooked requirement for normal wound healing. Inadequate protein-calorie nutrition, even after just a few days of starvation, can impair normal wound-healing mechanisms. For healthy adults, daily nutritional requirements are approximately 1.25-1.5 g of protein per kilogram of body weight and 30-35 calories/kg.  These requirements should be increased for those with sizable wounds.

Malnutrition should be suspected in patients presenting with chronic illnesses, inadequate societal support, multisystem trauma, or GI or neurologic problems that may impair oral intake. Protein deficiency occurs in about 25% of all hospitalized patients.

Chronic malnutrition can be diagnosed by using anthropometric data to compare actual and ideal body weights and by observing low serum albumin levels. Serum prealbumin is sensitive for relatively acute malnutrition because its half-life is 2-3 days (vs 21 d for albumin). A serum prealbumin level of less than 7 g/dL suggests severe protein-calorie malnutrition.

Vitamin and mineral deficiencies also require correction. Vitamin A deficiency reduces fibronectin on the wound surface, reducing cell chemotaxis, adhesion, and tissue repair. Vitamin C is required for the hydroxylation of proline and subsequent collagen synthesis.

Vitamin E, a fat-soluble antioxidant, accumulates in cell membranes, where it protects polyunsaturated fatty acids from oxidation by free radicals, stabilizes lysosomes, and inhibits collagen synthesis. Vitamin E inhibits prostaglandin synthesis by interfering with phospholipase-A2 activity and is therefore anti-inflammatory. Vitamin E supplementation may decrease scar formation.

Zinc is a component of approximately 200 enzymes in the human body, including DNA polymerase, which is required for cell proliferation, and superoxide dismutase, which scavenges superoxide radicals produced by leukocytes during debridement.


From, “Worldwide Wound Management, Forecast to 2026: Established and Emerging Products, Technologies and Markets in the Americas, Europe, Asia/Pacific and Rest of World”. Report #S254. Available online.