wounds. in medicine, a wound is a type of injury in which the skin is torn, cut or punctured (an...
TRANSCRIPT
Wounds
Wounds
In medicine, a wound is a type of injury in which the skin is torn, cut or punctured (an open wound), or where blunt force trauma causes a contusion (a closed wound). In pathology, it specifically refers to a sharp injury which damages the dermis of the skin.
Wounds
Open
Closed
A laceration to the leg
Open wounds can be classified according to the object that caused the wound. The types of open wound are:
Incisions or incised wounds, caused by a clean, sharp-edged object such as a knife, a razor or a glass splinter.
Open wounds
Lacerations, irregular tear-like wounds caused by some blunt trauma. For example, a blunt impact to soft tissue that lies over bone, or a tearing of skin and other tissues caused by childbirth. Lacerations from blunt impacts may show bridging, as connective tissue or blood vessels are flattened against the underlying hard surface.The term laceration is commonly misused in reference to incisions.
Open wounds
Abrasions (grazes), superficial wounds in which the topmost layer of the skin (the epidermis) is scraped off. Abrasions are often caused by a sliding fall onto a rough surface.
Puncture wounds, caused by an object puncturing the skin, such as a nail or needle.
Open wounds
Penetration wounds, caused by an object such as a knife entering the body.
Gunshot wounds, caused by a bullet or similar projectile driving into or through the body. There may be two wounds, one at the site of entry and one at the site of exit, such is generally known as a through-and-through.
In a medical context, stab wounds and gunshot wounds are considered major wounds.
Open wounds
Closed wounds have fewer categories, but are just as dangerous as open wounds. The types of closed wounds are:
Contusions, more commonly known as bruises, caused by blunt force trauma that damages tissue under the skin.
Closed wounds
Hematomas, also called blood tumors, caused by damage to a blood vessel that in turn causes blood to collect under the skin.
Crushing injuries, caused by a great or extreme amount of force applied over a long period of time.
Closed wounds
To heal a wound, the body undertakes a series of actions collectively known as the wound healing process.
Healing
Bacterial infection of wound can impede the healing process and lead to life threatening complications. Scientists at Sheffield University have identified a way of using light to rapidly detect the presence of bacteria. They are developing a portable kit in which specially designed molecules emit a light signal when bound to bacteria. Current laboratory-based detection of bacteria can take hours or even days
Infection
Cultural history
From the Classical Period to the Medieval Period, the body and the soul were believed to be intimately connected, based on several theories put forth by the philosopher Plato. Wounds on the body were believed to correlate with wounds to the soul and vice versa; wounds were seen as an outward sign of an inward illness.
Thus, a man who was wounded physically in a serious way was said to be hindered not only physically but spiritually as well. If the soul was wounded, that wound may also eventually become physically manifest, revealing the true state of the soul.
Cultural history
Wounds were also seen as writing on the "tablet" of the body. Wounds gotten in war, for example, told the story of a soldier in a form which all could see and understand, and the wounds of a martyr told the story of their faith.[
Cultural history
Cultural history
The International Red Cross wound classification system is a system whereby certain features of a wound are scored: the size of the skin wound(s); whether there is a cavity, fracture or vital structure injured; the presence or absence of metallic foreign bodies. A numerical value is given to each feature (E, X, C, F, V, and M). The scores can later be graded according to severity and typed according to the structures injured.
International Red Cross Wound Classification System
International Red Cross Wound Classification System
This scoring system is intended for quick and easy use in the field.
Wounds are scored after surgery or initial assessment.
International Red Cross Wound Classification System
E = (Entry) centimetres. Estimate the maximum diameter of the entry.
X = (eXit) centimetres. Estimate the maximum diameter of the exit (X = 0 if no exit).
C = (Cavity) Can the "cavity" of the wound take 2 fingers before surgery? No: C=0, Yes: C=1.
International Red Cross Wound Classification System
This may be obvious before operation or only established after skin incision. For chest and abdominal wounds it refers to the wound of the chest or abdominal wall. F = (Fracture) No fracture: F=0. Simple fracture, hole or insignificant comminution: F=1. Clinically significant comminution: F=2.
International Red Cross Wound Classification System
V = (Vital structure) Are brain, viscera (breach of dura, pleura or peritoneum) or major vessels injured? No: V=0. Yes: V=1.
M = (Metallic body) Bullet or fragments visible on X ray. None: M=0. One metallic body: M=1. Multiple metallic bodies: M=2.
International Red Cross Wound Classification System
The wound classification system has been criticised on the basis that "it fails to account for the synergistic effect of combined arms employment on the battlefield. It erroneously assumes that each soldier will be injured or killed by only one type of weapon.”
International Red Cross Wound Classification System
The classification is typically found on hospital Trauma History and Examination Record forms and is used for classification of penetrating injuries on presenting patients.
The International Committee of the Red Cross (ICRC) was founded in 1863; it promoted the Geneva Conventions which have been signed by 165 countries. These conventions protect victims of war, be they wounded, shipwrecked, prisoners of war or civilians.
Furthermore, they protect the hospitals and the medical staff who care for the sick and wounded.
Within the framework of these conventions, the mandate of the ICRC is to take action and propose humanitarian initiatives in armed conflict. Bringing surgical care to victims of war, whether combatant or civilian, where there is little or no medical infrastructure is an increasing part of the ICRC's activities.
Over the last 10 years, enormous experience has been gained in the surgical management of victims of war. The Medical Division of the ICRC is endeavoring to retrieve this experience; part of this retrieval takes the form of the Red Cross classification of wounds.
The Medical Division of the ICRC hopes to benefit the victims of war by passing on its experience to others who have to manage war wounds.
Dr. Remi Russbach,ICRC Chief Medical Officer
Surgeons from civilian practice may have no previous experience of managing war wounds. Preparation for war surgery involves an understanding of wounds. Texts concerning wound ballistics based on laboratory work are intended to provide a basis for understanding wound management. The most valuable information derived from these studies is that small missiles may cause large and serious wounds.
Misunderstandings arise because these studies focus on bullets when, in armed conflict, the majority of wounds are actually caused by fragments from bombs, shells or mines. When undertaking war surgery, the surgeon rarely knows the weapon nor does he find a uniform pattern of wounding.
The surgical task presented by any wound depends on the wound severity i.e. the degree of tissue damage and also the structure(s) that may have been injured. Recognition of this demands a clinical classification of wounds that is based on the features of the wound and not on the weaponry or the presumed velocity of the missile.
The Red Cross wound classification is a system whereby certain features of a wound are scored: the size of the skin wound(s); whether there is a cavity, fracture or vital structure injured; the presence or absence of metallic foreign bodies. A numerical value is given to each feature as shown overleaf. The scores can later be graded according to severity and typed according to the structures injured.
This scoring system is intended for quick and easy use in the field.
Skin wounds Cavity Fracture Vital structure(s) injured Metallic fragments (X ray)
A patient with a gunshot wound of the head. The entry is on the forehead
The radiographs show the small entry and exit wounds of the cranium and a linear fracture.
This is a serious wound because of the structure injured. (E 1, X 1, C 0, F 1, V 1, M 0; Grade 1, Type VF).
Fragment injury of the right leg. Both entry and exit wounds are large.
This is a serious wound because of the amount of tissue damage. The patient subsequently had above knee amputation.
(E 25, ? X 5, C 1, F 2, V 0, M 0; Grade 3, Type F).
SCORING THE WOUNDS IN THE FIELD
Wounds are scored after surgery or initial assessment.
E = (entry) centimetres. Estimate the maximum diameter of the entry. X = (exit) centimetres. Estimate the maximum diameter of the exit
(X = 0 if no exit).
C = (cavity) C0, C1
Can the "cavity" of the wound take 2 fingers before surgery?
No: C = 0, Yes: C = 1.
This may be obvious before operation or only established after skin incision. For chest and abdominal wounds it refers to the wound of the chest or abdominal wall.
F = (fracture) F0, F1, F2
No fracture: F = 0. Simple fracture, hole or
insignificant comminution: F = 1. Clinically significant comminution: F=2.
V = (vital structure) V0, V1
Are brain, viscera (breach of dura, pleura or peritoneum) or major vessels injured?
No: V= 0. Yes: V= 1.
M= (metallic body) M0, M1, M2
Bullet or fragments visible on X ray. None: M = 0. One metallic body: M = 1. Multiple metallic bodies: M = 2.
Wound healing
Classification of wounds Clean: non-traumatic wounds with no break
in surgical technique, no septic focus, and no viscus opened (e.g. hernia repair)
Clean-contaminated: non-traumatic wounds with contaminated entry into a viscus but with minimal spillage (e.g. elective cholecystectomy)
Wound healing
Contaminated: clean, traumatic wounds, or significant spillage from a viscus, or acute inflammation (e.g. emergency appendicectomy)
Dirty: includes traumatic wounds from a dirty source, or when significant bacterial contamination or release of pus is encountered
General principles of healing
Tissue healing in any organ follows some basic principles.
Cells may be labile (good capacity to regenerate, e.g. surface epithelial cells), stable (capacity to regenerate slowly, e.g. hepatocytes), or permanent (no capacity to regenerate, e.g. nerve and striated muscle cells).
General principles of healing
Tissue architecture is important: complex arrangements cannot be reconstructed if destroyed, e.g. renal glomeruli.
Complete restitution occurs when part of a labile population of cells is damaged, e.g. a minor skin abrasion.
General principles of healing
Granulation tissue is the combination of capillary loops and myofibroblasts. This is unrelated to a granuloma.
Organization is the process where specialized tissues are repaired by formation of mature connective tissue, e.g. pneumonia or infarcts.
General principles of healing
Wound contraction mediated by myofibroblasts can reduce the tissue defect by up to 80%, but can lead to problems, e.g. burns, contractures.
Collagen is secreted at the same time to form a scar.
General principles of healing
Tissue healing in any organ follows some basic principles.
Cells may be labile (good capacity to regenerate, e.g. surface epithelial cells), stable (capacity to regenerate slowly, e.g. hepatocytes), or permanent (no capacity to regenerate, e.g. nerve and striated muscle cells).
General principles of healing
Tissue healing in any organ follows some basic principles.
Cells may be labile (good capacity to regenerate, e.g. surface epithelial cells), stable (capacity to regenerate slowly, e.g. hepatocytes), or permanent (no capacity to regenerate, e.g. nerve and striated muscle cells).
The four stages of wound healing
When specialized tissue is destroyed it cannot be replaced, and a stereotyped response called repair then follows in four stages.
Haemostasis Inflammation Proliferation Remodelling
Haemostasis
Haemostasis: immediate. In response to exposed collagen, platelets aggregate at the wound and degranulate, releasing inflammatory mediators. Clotting and complement cascades activated. Thrombus formation and reactive vasospasm achieve haemostasis
Inflammation
Inflammation: 0-3 days. Vasodilatation and increased capillary permeability allow inflammatory cells to enter wound, and cause swelling. Neutrophils amplify inflammatory response by release of cytokines; reduce infection by bacterial killing; and debride damaged tissue.
Inflammation
Macrophages follow and secrete cytokines, growth factors, and collagenases. They phagocytose bacteria and dead tissue and orchestrate fibroblast migration, proliferation, and collagen production
Proliferation
Proliferation: 3 days-3 weeks. Fibroblasts migrate into the wound and synthesize collagen. Specialized myofibroblasts containing actin cause wound contraction. Angiogenesis is stimulated by hypoxia and cytokines and granulation tissue forms
Remodelling
Remodelling: 3 weeks-1 year. Re-orientation and maturation of collagen fibres increases wound strength.
Factors affecting wound healing
Impaired arterial supply or venous drainage (global or local).
Excessive movement, local distension, or distal obstruction.
Infection, malignancy, foreign body, necrotic tissue, smoking.
Malnutrition: obesity, recent weight loss, nutrient deficiency.
Factors affecting wound healing
Immunosuppressive: cancer, steroids, immunosuppressants, HIV.
Anticancer therapies: radiotherapy and chemotherapy.
Metabolic: diabetes, jaundice, uraemia, musculoskeletal diseases, age.
Wound healing in specific tissuesSkin: first intention healing
This takes place where there is close apposition of clean wound edges.
Thrombosis in cut blood vessels prevents haematoma formation.
Coagulated blood forms a surface scab that keeps the wound clean.
Fibrin precipitates to form a weak framework between the two edges.
Skin: first intention healing
Capillaries proliferate to bridge the gap. Fibroblasts secrete collagen into the fibrin
network. Basal epidermal cells bridge the gap and are
eventually resorbed. The elastic network in the dermis cannot be
replaced.
Skin: second intention healing
This takes place in wounds where skin edges cannot be cleanly apposed.
There is phagocytosis to remove debris. Granulation tissue to fill in defects. Epithelial regeneration covers the surface.
Gastrointestinal tract
Erosion is loss of part of the thickness of the mucosa.– Adjacent epithelial cells proliferate to regenerate
the mucosa.– Healing may take place this way in a matter of
hours.
Gastrointestinal tract
Ulceration is loss of the full thickness of the mucosa.– Mucosa is replaced from the margins.– The muscularis propria cannot be regenerated: it
is replaced by scar.– Damaged blood vessels bleed; fibrin covers the
raw surfaces.– Macrophages migrate in and phagocytose dead
tissue.
Gastrointestinal tract
– Granulation tissue is produced in the base.– If the cause persists the ulcer becomes chronic.– Fibrous scar tissue may result in contractions.
Wound closure types are divided into primary, secondary, and tertiary repair
In primary, or first-intention, closure, the wounds are sealed immediately with simple suturing, skin graft placement, or flap closure, such as closure of the wound at the end of a surgical procedure.
Closure by secondary, or spontaneous, intention involves no active intent to seal the wound. Generally, this type of repair is associated with a highly contaminated wound and will close by re-epithelialization, which results in contraction of the wound.
Wound closure by tertiary intention is also referred to as delayed primary closure. A contaminated wound is initially treated by repeated débridement, systemic or topical antibiotics, or negative pressure wound therapy for several days to control infection. Once the wound is assessed as being ready for closure, surgical intervention, such as suturing, skin graft placement, or flap design, is performed.
Thank you for your attention!