How to Be Healthy: Wound Healing
Wondering how to deal with cuts, grazes and lacerations? Forget everything you’ve been told and keep it moist, says Pat Thomas
Your skin is your body’s biggest organ and plays a large role in keeping you healthy. It helps to regulate body temperature and acts as a barrier, keeping body fluids in and bacteria out.
The skin also acts as a first-alert system by registering heat or pain – signals that can spell risk of injury.
Given optimum conditions, the human body is remarkably efficient at repairing injuries to this amazing wraparound material. Yet for years, as in so many areas of medicine, we have tried to improve on nature by applying sutures, harsh antiseptics and lots of dry, absorbent bandages to ‘help’ wounds heal better. In recent years these practices have been put under scrutiny – and many of them have been shown to be more destructive than helpful.
For instance, even though a healthy body is well equipped to fight off invading bacteria, wounds have been rubbed with alcohol, antibiotics, iodine, mercurochrome, merthiolate, hydrogen peroxide and other medications to keep them ‘clean’.
Today, antiseptics such as hydrogen peroxide, povidone iodine, acetic acid, chlorohexadine, cetrimide and Dakin solution (sodium hypochlorite) all find a place in many a family medicine cupboard. Unfortunately, many of these strong antiseptics can also interfere with the body’s own healing mechanisms.
Cleaning a wound is often the first hurdle at which we fall, since antiseptic solutions can interfere with the process of wound healing in several important ways. All wounds need to be cleaned before they are treated. The problem is that antiseptics don’t just kill germs, they also kill beneficial leucocytes, the body’s own bactericidal cells, as well as fibroblasts – cells that eventually form new skin.
Current thinking is that all but the worst types of wounds can be safely and effectively washed with a simple saline solution. Very dirty wounds can be cleaned with water pressure – in hospitals, staff may use special equipment; at home, running water or a showerhead may be just as effective. Likewise, attitudes to ‘simple’ bandages – used to keep the wound clean and dry – are changing.
No one would argue over the benefits of keeping a wound clean. But keeping it dry, usually with a gauze bandage that allows air to get to the site, and allowing a scab to form, can actually slow the healing process and is more likely to leave a scar. As far back as the 1960s, research was showing that wounds that were kept moist healed twice as quickly as those left to dry.
However, only relatively recently have gauze-based bandages given way to ‘semi-occlusive’ bandages that effectively maintain the moisture balance on the wound site by sealing it off, all the while allowing the transmission of oxygen, nitrogen and water vapour.
Perhaps the most important benefit of a moist bandage is that it provides an optimum environment for cells to stay alive and replicate. The natural environment of the cell is moist.
Dry cells – for instance, hair and nails – are dead cells, incapable of reproducing at their point of origin. And while traditional thinking is that the scab is nature’s own barrier to moisture loss, newer thinking sees the scab as an inefficient barrier to moisture loss. Scabs also prevent new cells from colonising the wound area.
When a scab is allowed to form, epidermal cells have to penetrate deeper into the dermis – where the environment is moist – before they can proliferate. This means that the wound will only heal from the bottom up. In a moist environment the wound heals from the sides and bottom simultaneously.
Newer dressings such as polymer films and foams, hydrocolloids, hydrogels and calcium alginates allow much less evaporation of moisture, leaving the cells responsible for the filling and resurfacing the wound in an environment in which they are able to live and replicate.
These dressings may also act as insulation, helping to maintain the optimum temperature of the skin. (However, some researchers, using laboratory tests, have found that some types of synthetic dressings can be toxic to developing cells – a problem similar to that experienced when such materials are used as prosthetics. This area is poorly researched and few people have actively questioned the use of potentially carcinogenic materials such as polyvinyl pyrollidone as ‘healing’ dressings.)
Moist dressings are also many times more effective than dry dressings in preventing infections. This is as important an aspect of healing to the child in the playground as it is to the patient in hospital, where opportunistic antibiotic-resistant bacteria can so easily enter a wound site. In this respect, moist healing is something of a paradox.
Most of us would assume that a moist environment would be a breeding ground for germs, but this belief does not acknowledge how efficient the body can be at fighting infection. Nor does it acknowledge that a wound colonised by bacteria is not necessarily a risk for infection.
All wounds, no matter how carefully cleaned, are colonised by bacteria. The problem arises when bacteria are given the opportunity to multiply. In a properly nourished body, natural infection-fighting mechanisms can effectively keep bacteria in check. A great deal of data has been amassed on this subject and the overall conclusion is that moist healing actually decreases infection rates significantly.
One reason for this may be that a moist dressing helps to maintain the slightly acidic condition of the skin. This too may inhibit certain types of bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa. Patients also report less pain when wounds are kept moist.
Newer dressings are thought to protect nerve endings from the environment and keep them moist, again reducing the perception of pain. With gauze dressings, nerve endings may be damaged during changes. Numerous studies involving people from all walks of life and all occupations, including footballers and industrial workers, attest to the fact that patients treated with hydrocolloid dressings experience less pain.
Moist dressings may also benefit patients aesthetically: studies show, for instance, that they can help lessen the appearance of scars. All wound areas are colonised by bacteria such as Pseudomonas aeruginosa
Sidebar: Try these first
Taking care of a wound or cut is largely a matter of common sense. When self-treating, consider these options to help support the body’s own efficient healing process.
Keep it clean From time to time during the healing process, clean the wound with a gentle saline solution: put two teaspoons of salt into a litre of boiling water and allow to cool.
Use natural antiseptics A good first choice is Echinacea angustifolia, which fights infection and promotes healing. Others include calendula, tea tree and lavender.
Boost your protein intake Skin is made of protein and extra is required when you are injured. This is especially true for those having an operation, as surgery increases calorie and protein needs by 20-50 per cent.
Take supplements Vitamin A helps to form scar tissue; B1 deficiency can interfere with collagen synthesis; vitamin B5 accelerates the healing process. Vitamin C promotes the formation of collagen and elastin; deficiency can slow the healing process. Vitamin E aids in the healing of skin grafts; zinc stimulates wound healing. Essential fatty acid deficiencies are associated with poor wound healing.
Heal it with honey, which contains enzymes and anti-viral substances. In studies, honey impregnated gauze promoted faster healing and resulted in less infection than synthetic semi-occlusive dressings. Honey has also been found to promote the growth of new skin cells.
- This article first appeared in the July/August 2007 edition of the Ecologist
