The global annual market for products used in wound management is currently a behemoth of $20.2 billion. The wound management forecast to 2026 shows the global market hitting $38 billion as it grows in response to strong wound care demand.
The market is driven by inescapable demographics — an aging population, with dramatically increasing prevalence of obesity and diabetes leading to growth in the most expensive types of wounds, chronic wounds. The market is also growing as a result of advanced wound technologies that improving in their ability to shorten healing time, costs, or both.
Chronic wound remain a big focus, for good reasons. From our press release:
“Our recent research shows that chronic wounds, which have long been no secret to clinicians, epidemiologists, and product manufacturers as a growing health problem, are actually even more prevalent and costly than has been previously reported.”
Care of chronic wounds is a significant, global burden on healthcare systems. In the USA alone, it is estimated that at least 6.7 million people suffer with chronic wounds, requiring treatment in excess of $20-50 billion per year .
With many, many active companies in an industry that started hundreds of years ago, an almost continuous spectrum of products exists from low tech (gauze) to high tech (bioengineered skin):
negative pressure wound therapy (NPWT)
bioengineered skin & skin substitution
Growth in sales varies, with the lowest rates for traditional products and the highest rates generally for the advanced products. We say generally because, depending upon the product and the geographic location, sales growth rates can be considerable. The end result is that the makeup of the wound market will change from 2016 to 2026. See below:
The wound care industry remains quite fragmented, with about eight companies holding leading market shares, but with possibly thousands of small cap companies around the world that are also manufacturing and marketing various wound care products. The Traditional Wound Care space remains attractive, in part since gauze dressings are relatively easy to manufacture and are also still the most commonly-used wound dressing.
The MedMarket Diligence Report #S254 is described in detail at link.
Separate size, growth and competitor data are presented for the U.S., rest of North America, Latin America, leading western European countries (specifically, United Kingdom, Germany, France, Italy, Spain), rest of Europe, Japan, Korea, rest of Asia/Pacific, and the Rest of World category. The report’s company profiles assess 92 leading and key emerging companies regarding current/projected products, technologies and positions in the advanced wound care market.
Healthcare systems move billions in global wound care sales, yet chronic wounds still are a chronic problem. Despite the legion of products developed for wound care, from dressings to bioengineered skin, the obesity- and age-driven increase in chronic slow-healing and non-healing wounds plague healthcare systems globally. Results according to MedMarket Diligence’s biennial, 2018 Wound Management report (#S254).
BIDDEFORD, Maine – April 1, 2018 – PRLog — Research and routine clinical practice in wound management have advanced the science to better understand and address chronic wounds, but much work remains for research and manufacturing to impact the growing caseload.
Chronic wounds represent a large but still underestimated problem for health systems globally and industry needs to step up in response, according to MedMarket Diligence, LLC.
“Our recent research shows that chronic wounds, which have long been no secret to clinicians, epidemiologists, and product manufacturers as a growing health problem, are actually even more prevalent and costly than has been previously reported,” says Patrick Driscoll of MedMarket Diligence, who has tracked wounds in clinical practice and industry for 25 years.
Care of chronic wounds is a significant, global burden on healthcare systems. In the USA alone, it is estimated that at least 6.7 million people suffer with chronic wounds, requiring treatment in excess of $20-50 billion per year (estimates vary according to the definitions). A report from the UK suggests, based on National Health System (NHS) data, that chronic wound prevalence in developed countries is about 6% and that care of chronic wounds accounts for around 3-5.5% of total healthcare spending in those countries. (Phillips CJ, et al. Estimating the costs associated with the management of patients with chronic wounds using linked routine data. Int Wound J. 2015. doi: 10.1111/iwj.12443.)
Definitions help clinicians determine whether a wound is healing or not. For example, for venous leg ulcers (VLUs), if the wound has not shown at least a 40% reduction in wound size in about four weeks, then additional therapies are called for. A non-healing foot ulcer is generally defined to be any ulcer that is unresponsive to standard therapies and persists after four weeks of standard care. Once a foot ulcer occurs, unfortunately some 60% of patients end up moving into the chronic non-healing category. Many diabetics develop foot ulcers.
Chronic wounds and burns continue to present challenging clinical problems. For example, chronic wounds may present with persistent infections, inflammation, hypoxia, non-responsive cells at the wound edge, the need for regular debridement, etc. For DFUs, it is important for the patient to continuously wear an offloading device such as a special boot. Additionally, the practitioner must carefully debride not only the necrotic tissue in the wound bed, but the wound edges. Cells at the wound edge seem to be unresponsive to typical healing signals, and therefore must be removed to promote and support proper healing.
To the person with a chronic wound, the condition represents pain, social and psychological debilitation and usually a financial load. To society, wound care—and especially the treatment of difficult-to-heal wounds—may represent great human suffering, social discomfort, days lost from work, mental health problems, recurrent infections and great economic burden and the human burden of wound care. Having a chronic wound not only necessitates physical care of the wound, including cleaning, disinfecting, irrigating, and changing dressings; it also impacts the emotional and psychological health of the patient. Depression can set in due to a lower quality of life and dependence on others for care of the wound, as well as for overall assistance, both physical and financial. Wounds may cause odors or may have visible drainage, staining clothing and triggering feelings of embarrassment and shame. These in turn may lead to isolation due to decreased mobility and the fear of being a burden on family and friends. To make things worse, increased stress can slow the progress of wound healing. For all of these reasons, chronic wounds drive product development.
In caring for a chronic wound, the dressing costs are only part of the picture; the less visible costs include such items as nursing care, medications for pain and infections, and hospitalization. Hospitalization is a leading cost driver for wound care, accounting for at least 50% of the global economic burden. Nursing time to properly care for the patient with a chronic wound can be lengthy, and this is time that could be spent with other patients. In a new report published in the December 2017 online version of the International Society for Pharmacoeconomics and Outcomes Research’s (ISPOR) Value in Health journal (An Economic Evaluation of the Impact, Cost, and Medicare Policy Implications of Chronic Nonhealing Wounds. Nussbaum, Samuel R. et al. Value in Health, Volume 21 , Issue 1 , 27 – 32) (see the study), the researchers found that the costs related to wound care in the Medicare population (USA) were much higher than originally estimated, and that care took place primarily in outpatient settings. For the calendar year 2014, there is considerable variation in the estimates originating from different sources:
“Total Medicare spending estimates for all wound types ranged from $28.1 to $96.8 billion. Including infection costs, the most expensive estimates were for surgical wounds ($11.7, $13.1, and $38.3 billion), followed by diabetic foot ulcers ($6.2, $6.9, and $18.7 billion,). The highest cost estimates in regard to site of service were for hospital outpatients ($9.9–$35.8 billion), followed by hospital inpatients ($5.0–$24.3 billion).”
The development of advanced wound care dressings, devices and biologics is helping to change this situation. Although these advanced products may seem (or may be) expensive, they end up saving money for health care systems by healing wounds more rapidly.
The wound care industry remains quite fragmented, with about eight companies holding leading market shares, but with possibly thousands of small cap companies around the world that are also manufacturing and marketing various wound care products. The Traditional Wound Care space remains attractive, in part since gauze dressings are relatively easy to manufacture and are also still the most commonly-used wound dressing. Even a small company can invent a novel twist to a dressing and experience a rise in profits and inroads into the market.
Low to medium industry concentration. As the traditional and advanced market shares diagrams below demonstrate, there are five to eight major players in Traditional and Advanced Wound Care Markets.
While these firms account for about 79% and 73% of the total markets, respectively, a significant portion of these markets are covered by hundreds or thousands of Other companies. This low to medium level of concentration means that smaller companies, or large companies looking to break into Wound Care, are able to do so more easily than if, say, three companies controlled 95% of the market.
Johnson & Johnson is estimated to be the Traditional Wound Care market leader with about 26% share, followed by Smith & Nephew, 3M Health Care and Hartmann. Medline Industries is estimated to account for about 8%, while Others account for about 21% of this market.
Breaking into the Advanced Wound Care markets presents a somewhat greater challenge. Here, the leading companies have invested heavily in R&D to gain strategic competitive advantage, as well as to create improved products for patients. Smith & Nephew is holds an estimated 21% of this market, followed by Acelity and Johnson & Johnson with 11% each, and Mölnlycke, 3M Health Care, Hartmann, Cardinal Health and ConvaTec accounting for smaller shares. Here again, Others accounts for at least 27% of this market.
Opportunities exist in both Traditional and Advanced Wound Care, especially if a company is in the position of acquiring part or all of an existing wound care company, and if the company can then invest in the development of its new products. If points of distribution overlap, then so much the better.
Relatively low barriers to entry. Good news for companies wishing to break into wound care: barriers to entry into the traditional wound dressing segments (Adherents, Gauze and Non-Adherent Dressings) are relatively low, while demand remains strong. Typically, once a company is established in a traditional segment, it may either plow revenues into research and development, or it may acquire companies to more easily break into new product segments and markets. Many companies in wound care have followed just this path to gain market share and make an impact in the industry.
From, “Wound Management to 2026”; Report S254. Excerpts available.
The clinical driver of sales in wound care is the prevalence of different wound types and the associated cost to manage them. While surgical wounds made by primary intent as part of surgical procedures (e.g., excision of skin lesion, appendectomy, coronary artery bypass graft, etc.) represent the biggest source of wounds, the biggest focus on reining in costs in medtech is slow-healing, chronic wounds, such as ulcers.
We have projected the global prevalence for the most common wound types through 2026, shown below.
Generally, the longer the product has been around (e.g., gauze), the less complex it is compared to emerging technologies…
…BUT simpler is easy to adopt and, with well established sales, growth on a percentage basis will be low (see area in red)..’
Generally, new technologies incorporate rarer materials, have more complex construction, and may cost considerably more…
…BUT complex technologies may be far more effective clinically than older technologies and may allow treatment where no older technology could, and with low initial sales (penetrated potential), growth on a percentage bases will be high (see area in green).
Country and Regional Variation in Growth Rates
While this size-to-growth dynamic exists for most product types, the dynamic varies from one geographic region to the next. The time point at which a particular product/technology starts to be more rapidly adopted — or the rate at which use of established products are use starts to decline — can vary considerably from country to country.
As a result, there will be variability in sales growth rates for a product in one country/region versus another.
For example, the 2017 to 2026 compound annual growth rate in sales of Alginates in wound management range from a low of 5.3% in one country to a high of 24.3% in another country. (If you make alginates, in which country would YOU like to compete?)
Regionally, as in USA versus Europe versus Asia/Pacific, etc., there is less variation in growth rates for any given product in that region. For alginates:
country-to-country variation in CAGR: 19%
region-to-region variation in CAGR: 7.8%
In other words, the difference between the countries with the highest and lowest CAGRs for alginate sales is 19%, while the difference between regions shows one region with a 7.8% higher CAGR for alginates than the lowest growth region.
The demand for surgical sealants, glues, and hemostats is directly related to the clinical caseload and procedure volumes, while product choice is dependent upon the surgeon’s training and experience with the products, the particular situation, and product availability. Availability is influenced by several factors. For example, must the product be prepared before use, or is it ready to use off the shelf? Is it refrigerated, requiring warming prior to use, or is the product able to be stored at room temperature? Availability also depends on whether the hospital or healthcare facility will stock the product, which in turn depends on the product’s cost and whether it fits into the facility’s budget and formulary. Sealants, glues and hemostats are used about 25% of the time in many (but not all) procedures, since sutures remain the most familiar and least expensive products for wound closure. However, the products addressed in this report could well find use in over 100 million procedures globally.
Here are six key trends we see in the global market next in surgical sealants, glues, hemostats:
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.
Rapid adoption of sealants, glues, and 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.
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.
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.
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.
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”.
Today’s surgeon has a broad range of products from which to choose for closing and sealing wounds. These include sutures, stapling devices, vascular clips, ligatures, and thermal devices, as well as a wide range of topical hemostats, surgicalsealants and glues.
However, surgeons still primarily use sutures for wound closure and securement—sutures are cheap, familiar and work most of the time. Now, in addition to reaching for a stapling device, the surgeon must frequently decide at what point to augment or replace the commonly used items in favor of other products, which product is best for what procedure or condition, how much to use, and ease of use in order to achieve optimal patient outcomes. Because of budget pressures, the surgeon must also consider price when selecting a product. Of course in the USA, the product must also be FDA-approved, although the surgeon still has the choice of using a product off-label.
In the areas of sealants, hemostats and glues, there is room for both improvement and additional products. There are a number of products already on the market, but the fact is that there is no one product that meets all needs in all situations and procedures. There are few products that stand out from the rest, apart, perhaps, from DermaBond® and BioGlue®. There are unmet needs, and companies having the necessary technology, or which may acquire and further develop the technology, can enter this market and launch novel items. These products have yet to significantly tap the potential for wound management and medical/surgical procedures.
Note: Log10 scale; Chronic wounds includes pressure, venous/arterial and diabetic ulcers.
Numerous variants of fibrin sealant exist, including autologous products. “Other” sealants refers to thrombin, collagen & gelatin-based sealants.
Fibrin sealants are used in the US in a wide array of applications; they are used the most in orthopedic surgeries, where the penetration rate is thought to be 25-30%. Fibrin sealants can, however, be ineffective under wet surgical conditions. The penetration rate in other surgeries is estimated to be about 10-15%.
Fibrin-based sealants were originally made with bovine components. These components were judged to increase the risk of developing bovine spongiform encephalopathy (BSE), so second-generation commercial fibrin sealants (CSF) avoided bovine-derived materials. The antifibrinolytic tranexamic acid (TXA) was used instead of bovine aprotinin. Later, the TXA was removed, again due to safety issues. Today, Ethicon’s (JNJ) Evicel is an example of this product, which Ethicon says is the only all human, aprotinin free, fibrin sealant indicated for general hemostasis. Market growth in the Sealants sector is driven by the need for improved biocompatibility and stronger sealing ability—in other words, meeting the still-unsatisfied needs of physician end-users.
High Strength Medical Glues
Similar to that of sealants, the current market penetration of glues in the US is thought to be about 25% of eligible surgeries. There are several strong points in favor of the use of medical glues: their use can significantly reduce healthcare costs, for example by reducing time in the surgical suite, reducing the risk of a bleed, which may mean a return trip to the OR, and general ease of use. Patients seem to prefer the glues over receiving sutures for an external wound, as glues can provide a suture-free method of closing wounds. In addition, if glues are selected over sutures, the physician can avoid the need (and cost) of administering local anesthesia to the wound site.
Hemostats are normally used in surgical procedures only when conventional bleeding control methods are ineffective or impractical. The hemostat market offers opportunities as customers seek products that better meet their needs. Above and beyond having hemostats that are effective and reliable, additional improvements that they wish to see in hemostat products include: laparoscopy-friendly; work regardless of whether the patient is on anticoagulants or not; easy to prepare and store, with a long shelf life; antimicrobial; transparent so that the surgeon continues to have a clear field of view; and non-toxic; i.e. preferably not made from human or animal materials.
Drawn from, “Worldwide Markets for Medical and Surgical Sealants, Glues, and Hemostats, 2015-2022: Established and Emerging Products, Technologies and Markets in the Americas, Europe, Asia/Pacific and Rest of World.”Report #S290.
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.
Estimated Worldwide Wound Prevalence by Etiology, 2015
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
Market shares for sales of sealants, glues, and hemostats vary considerably from region to region globally due to the significant variations in the local market demand, rate of adoption of specific manufacturers’ products, the regulatory climate, local economies, and other factors. Consequently, manufacturers with significant share of sales in the U.S. or Europe or Asia/Pacific may have considerably lower or higher shares in other regions.
In the U.S., Ethicon and Baxter have dominant positions in sales of surgical sealants. However, in Europe and Asia/Pacific, Baxter has substantially smaller position, particularly relative to competitors like Takeda Pharmaceuticals and The Medicines Company.
In the market for hemostats, similarly, Ethicon and Baxter have dominant position in the U.S. market, but in Asia/Pacific and Europe, Baxter is subordinate to Takeda Pharmaceuticals, CryoLife, and others.
Excerpted from, “Worldwide Wound Management, Forecast to 2024: Established and Emerging Products, Technologies and Markets in the Americas, Europe, Asia/Pacific and Rest of World”, 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.
Preparation of the wound bed (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:
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.
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.
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.
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.
Other factors such as alcohol abuse, smoking, and radiation therapy
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, 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 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 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 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 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 that directly affect the performance of healing are:
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.
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 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.
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 2024: Established and Emerging Products, Technologies and Markets in the Americas, Europe, Asia/Pacific and Rest of World”. Report #S251. Available online.