nhsManagers.net | Briefing | 11 November 2017 Medicine for Managers Dr Paul Lambden BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG MHSM FRSM Every day we encounter damage as a result of injury or accident, which may be extremely minor or, on occasion, which may be large. Any breach in the skin causes danger for the body. It may result in the ingress of germs or toxins, or the loss of blood or other body fluids. Your skin is a key first line of protection Skin damage may include lacerations, cuts, thermal or chemical burns, pressure damage such as bed sores or puncture wounds. The resulting damage may be linear, as with a knife, jagged as with a scraping laceration or widespread as with a burn. The damage may be confined to the skin or it may involve deeper structures such as muscles, tendons, ligaments, blood vessels, nerves or bones. Wound healing and resolution has been classified in different ways over the years but in general there can be considered to be several stages which lead to the closure and healing of the wound. The process is similar whether the wound is caused by a laceration with a jagged nail or a fine incision by a surgeon (although speed, degree of resolution and restoration of function may vary according to the initial condition of the wound) Haemostasis The first stage is to stop the bleeding. Immediately the wound occurs the clotting mechanism will start, resulting within about ten minutes, with the formation of a clot. It occurs because the blood vessels in the wound bed contract and blood components, including Medicine for Managers articles are not intended to be a source of medical advice. Their purpose is to familiarise the non-medical reader about current key medical disorders. Any medical or medicinal products mentioned by name are examples only and should not be regarded as an endorsement of their use. How Do Wounds Heal? Have you ever thought how clever it is that, when the body is wounded, it can pretty-much heal itself. It doesn’t matter whether the injury leading to the wound is acute or chronic. Miraculously, it gets to work to repair as much of the damage as it can. It may not be cosmetically ideal but it allows the body to continue to function.
Transcript
nhsManagers.net | Briefing | 11 November 2017
Medicine for Managers
Dr Paul Lambden BSc MB BS BDS FDSRCSEng MRCS LRCP DRCOG MHSM FRSM
Every day we encounter damage as a result of injury or accident, which may be extremely minor or, on occasion, which may be large.
Any breach in the skin causes danger for the body. It may result in the ingress of germs or toxins, or the loss of blood or other body fluids. Your skin is a key first line of protection
Skin damage may include lacerations, cuts, thermal or chemical burns, pressure damage such as bed sores or puncture wounds. The resulting damage may be linear, as with a knife, jagged as with a scraping laceration or widespread as with a burn.
The damage may be confined to the skin or it may involve deeper structures such as muscles, tendons, ligaments, blood vessels, nerves or bones.
Wound healing and resolution has been classified in different ways over the years but in general there can be considered to be several stages which lead to the closure and healing of the wound. The process is similar whether the wound is caused by a
laceration with a jagged nail or a fine incision by a surgeon (although speed, degree of resolution and restoration of function may vary according to the initial condition of the wound)
Haemostasis
The first stage is to stop the bleeding. Immediately the wound occurs the clotting mechanism will start, resulting within about ten minutes, with the formation of a clot. It occurs because the blood vessels in the wound bed contract and blood components, including
Medicine for Managers articles are not intended to be a source of medical advice. Their purpose is to familiarise the non-medical reader about current key medical disorders. Any medical or medicinal products mentioned by name are examples only and should not be regarded as an endorsement of their use.
How Do Wounds Heal? Have you ever thought how clever it is that, when the body is wounded, it can pretty-much heal itself. It doesn’t matter whether the injury leading to the wound is acute or chronic. Miraculously, it gets to work to repair as much of the damage as it can. It may not be cosmetically ideal but it allows the body to continue to function.
platelets and clotting factors rapidly travel to the damaged area. The platelets adhere to the wound edges and are responsible for the initial sealing of the wound. The coagulation factors are activated resulting in the production of fibrin strands which interweave and bind the developing clot together. The platelet plug once complete stops the blood loss. Red and white blood cells also form part of the clot. External bleeding stops.
Inflammatory Response
Inflammation is the body’s natural response to injury. Once the bleeding has been stopped the blood vessels dilate and a variety of essential cells arrive at the site .
They include white blood cells and antibodies to control and eliminate infection, enzymes to dissolve damaged tissue, nutrients and growth factors.
At this stage the classical appearances of inflammation can be seen around the wound; redness, heat and swelling and the wound may hurt or be painful to touch.
The involved area may also display functional disturbance. The predominant cells in the area are the phagocytic cells. They are various types of white blood cell, neutrophils and macrophages. They are scavengers and remove bacteria and debris. The wound may ooze pus which is formed of dead and dying white blood cells, dead bacteria and wound debris.
Proliferation and migration
As the inflammatory phase progresses the body releases different types of cells which become involved in processes called migration and proliferation. Migration
refers to a carefully co-ordinated process which involves cells moving in a specific manner and direction. Proliferation is an extension of the haemostatic process and involves further sealing of the wound. A new network of blood vessels starts to form in the area, a process called angiogenesis, to replace the vessels that were damaged in the injury. Granulation tissue grows, often quite exuberantly to restore any loss.
The fibroblast cells bind components of the wound together.
The granulation is recognisable because it has a granular and uneven texture, does
not bleed easily and is a pale pink in colour. The whole process is extraordinarily complex and requires amazing co-ordination.
Epithelialisation
Once the damaged tissue has been removed, the deficit has been replaced by granulation and new blood vessels have been formed, the body embarks on an
epitheliailisation process to regrow the damaged or lost skin.
The skin cells are called keratinocytes. The repaired skin is initially delicate but gradually thickens to forms a waterproof covering and part of the body’s integument.
Scar Tissue Formation
Scar tissue is formed of collagen fibres which is the same protein as the tissue it replaces but the fibres are arranged in a different way. Instead of being present in a random way such as occurs in normal skin, the fibres form cross links between the sides of a wound to bring the two edges together.
Medicine for Managers articles are not intended to be a source of medical advice. Their purpose is to familiarise the non-medical reader about current key medical disorders. Any medical or medicinal products mentioned by name are examples only and should not be regarded as an endorsement of their use.
The wound shows a variety of features of the healing process; the in f lammatory response including some white areas of debris, some granulation tissue which is more red and contains the proliferating repair cells and the rounding off and sealing of the wound edges from which the epithelial (skin) cells will develop.
Over time, fibres in the wound gradually contract which is why a scar becomes less prominent and apparent. Scar tissue is devoid of specialised structures and so it contains no sweat or oil glands or hairs. Scars are initially a reddish colour normally but they fade over time towards the colour of the surrounding skin.
Primary and Secondary Intention
Wounds may heal by primary or secondary intention.
Primary Intention occurs where the wound edges are in close proximity such as occurs in a surgical wound.
It occurs more quickly where the wound edges are opposed and the resulting scar is usually less apparent. The same healing processes occur but they are generally better controlled
Secondary Intention is the healing of those wounds where the margins are not opposed, as in the illustration in the box above.
In such circumstances the healing will be slower, the risks of infection or recurrent bleeding are greater and the resulting scar will be much more visibly intrusive.
Keloid scars
In any wound, however caused, a latter stage in the recovery involves scarring. They normally heal and shrink as the scar contracts. Sometimes, however, the scar does not contract and indeed continues to grow (proliferate) to form a lumpy, prominent, easily visible scar. They are most common in dark-skinned people and their incidence tends to run in families.
They are common in younger people and more frequently located on the head, shoulders and chest. They can however occur anywhere. Sometimes they may occur months or even years after the initial injury. It is not understood why keloid scarring occurs.
They are normally a cosmetic problem and are not sinister in any way.
The whole process of managing a wound to close it, repair it, form a barrier to the introduction of infection is truly amazing and a function for which most humans are frequently unknowingly very grateful.
Medicine for Managers articles are not intended to be a source of medical advice. Their purpose is to familiarise the non-medical reader about current key medical disorders. Any medical or medicinal products mentioned by name are examples only and should not be regarded as an endorsement of their use.
