VOL: 97, ISSUE: 35, PAGE NO: 55
Christine Dearden is A&E consultant at the Royal Hospitals and Dental Hospital Health and Social Services Trust, Belfast, Northern Ireland
Janice Donnell RGN, RSCN, is a staff nurse, Martina Dunlop RGN, BSc, is an emergency nurse practitioner at the Royal Hospitals and Dental Hospital Health and Social Services Trust, Belfast, Northern IrelandChristine Dearden is A&E consultant at the Royal Hospitals and Dental Hospital Health and Social Services Trust, Belfast, Northern Ireland
In the first instance, the care of a patient with a wound is always directed at preservation of life over limb. Information on initial assessment and management of the emergency patient can be found in a previous article in the series (Dearden et al, 2001a). This article will focus solely on local wound management for specific types of injury and should not be read in isolation - for details on wound cleansing, debriding and closure and the use of analgesia and antimicrobial agents refer to Dearden et al (2001b).
- Analgesia, cleansing and, if necessary, dermabrasion and debridement;
- Due to the superficial nature of these wounds most are left to heal by secondary intention;
- Although minor abrasions could be left exposed it is usually better to protect them with a non-adherent dressing. This reduces pain by preventing clothing from rubbing against the injury and sticking to it. It also reduces the risk of secondary infection (Thomas, 1990);
- Hydrocolloid dressings may help to lift grit and gravel from the wound.
A bite wound can range from a superficial scratch to a major tear. The degree of damage will largely depend on the type of animal inflicting the injury. For example, a small dog that grips and shakes its victim will produce extensive crushing injuries. Others that pounce and hold - for example, a cat, will create deep penetrating wounds (Fig 2).
All bites have the potential to introduce bacteria deep into the soft tissue where, after a short incubation period, they may proliferate and spread. The most potentially infective bite is that of human origin (Bradley and Collier, 1994).
A human bite injury may also manifest as a clenched fist injury - that is, as a clenched fist is forced against the teeth of an opponent, the skin lacerates and retracts. Teeth may gain access to the joint space and there is a high risk of tendon rupture and septic arthritis. As the hand is pulled away and relaxes, the skin returns to its original position, carrying dirt and bacteria deep into the wound.
- The cornerstone of treatment is analgesia, thorough cleansing and debridement and the prescription of antibiotics if infection occurs;
- Bite wounds, with the exception of those to the hand, may be sutured;
- Initially an iodine dressing that can help to reduce bacterial colonisation may be of benefit (Gilchrist, 1997). The secondary dressing will depend on the level of exudate;
- The wound should be assessed on a daily basis due to the high risk of spreading infection.
A contusion is essentially a bruise (Fig 3). It indicates damage to blood vessels that lie within or beneath the skin, fat or muscle. A contusion will change from red to blue as the red pigment haemoglobin loses its oxygen. This is later broken down into green and yellow bile pigments. As stagnant blood provides an ideal environment for bacteria to proliferate, any breach in the surface of the skin (allowing bacterial penetration) can result in significant infection. A haematoma is a larger collection of blood than a bruise.
- Monitor for signs of infection;
- The need to evacuate a haematoma is open to debate. However, our experience would suggest that better outcomes are achieved when large haematomas are evacuated.
A crush injury is caused by the impact of a blunt force. If the force is powerful enough it will fracture bones and cause extensive bleeding into the muscles. Crush injuries tend to have deep wound cavities, gaping, torn wound edges and large areas of devitalised tissue (Fig 4). They commonly occur in accidents involving machines, car doors and on construction sites. The location of the injury determines mortality or morbidity. For example, crush injuries to the chest can result in fractures to the ribs and involve internal organs such as the heart and lungs. However, the most common type of crush injury seen in A&E departments involve fingers.
Crushed tissues carry a high risk of infection from the presence of a large amount of devitalised tissue. Also, if the skin has been breached, organisms may gain access to the deeper tissues where they will find the perfect conditions to proliferate.
- Analgesia, thorough cleansing and debridement of all dead/devitalised tissue;
- Appropriate closure of the wound (Whiteside and Moorehead, 1999);
- Dressings that maintain a moist wound environment are recommended, as they aid autolysis (removal of debris and dead tissue) and promote granulation, although the choice will depend on the level of exudate. In finger or toe injuries dressings that mould around the digit are particularly useful.
- The wound should be assessed on a daily basis due to the high risk of spreading infection;
- Injured limbs should be elevated to reduce swelling.
Incised injuries (lacerations)
An incised injury is essentially a cut with a variable degree of tissue damage. It can range in appearance from a neat linear shape with minimal tissue loss to a tearing type of cut with a jagged wound edge and devitalised tissue (Fig 5). The appearance and depth of the cut will depend on the type of cutting instrument/object and the depth to which this cutting object has penetrated through the skin. The wound edges may gape and bleed profusely.
- Apply pressure to stem bleeding;
- Before wound treatment, check for damage to deep structures - for example, tendons and nerves. This is determined by examining tendon and nerve function distal to the injury and looking into the wound before closure; partially severed tendons may be seen which will require repair. If there is damage to underlying structures, the patient should be referred to an appropriate specialist for surgical repair (McNicholl et al, 1992);
- Cleanse and debride the wound thoroughly;
- If the wound is uncomplicated, approximate wound edges using an appropriate material such as adhesive strips, tissue glue, sutures or staples. The choice of material will depend on the area damaged and the type of tissue involved. For example, gaping lacerations over areas of tension, such as a joint surface, will need to be sutured;
- Cover the wound with a low-adherent dressing. Pad as appropriate. If necessary apply a pressure dressing.
Pre-tibial lacerations are relatively common injuries and affect the skin overlying the anterior aspect of the tibial bone (Fig 6). Classically, the wound contains a V-shaped flap of tissue that is attached to the wound on one side only, that is distally, laterally or proximally. A bluish tinge to the flap edge usually indicates that its blood supply has been compromised. There may also be contusion with or without haematoma formation.
- Remove underlying haematoma and make sure that the flap is in close contact with underlying structures. A necrotic wound edge should be debrided;
- Unfurl the tissue flap without tension. Note that the wound edges do not have to be opposed completely as the wound will heal by secondary intention;
- Apply adhesive paper strips without tension. Do not suture, as sutures are associated with a significantly increased incidence of necrosis and slower healing when compared with tapes in securing pre-tibial flaps (53v39 days) (Sutton and Pritty, 1985);
- Cover with a non-adherent dressing. Traditional type dressings such as Paraffin gauze and zinc paste bandages have been demonstrated to cause problems, such as adherence to the wound and pain on removal (Eagle, 1999; Premachandran et al, 1996). However, once the wound is covered with a non-adherent dressing, a zinc oxide paste bandage may be useful in immobilising the skin flap. If a paste bandage is used it should be applied from toe to knee in a pleated fashion - a complete spiral does not allow for swelling. This may be left in place for seven to 10 days;
- Healing may be enhanced through the use of graduated compression (Bradley, 2001). However, this must never be applied without first checking the ankle brachial pressure index (ABPI), which should be measured by a nurse with appropriate training in the procedure;
- Elevate the affected limb to reduce oedema and encourage ankle exercises to aid venous return.
This is rarely required.
- Primary excision of flap under general anaesthetic;
- Remove subcutaneous tissue and reapply flap as a skin graft, or apply a fresh skin graft;
- Dress wound as before. Consider graduated compression bandages.
Although penetrating wounds may be caused by wood splinters, thorns and bites, the term is usually used to describe wounds created by the insertion of a large foreign body, for example a screwdriver, knives, nails, bullets and shrapnel (Fig 7). The amount of damage caused depends on the amount of energy released by the object as it slices through the tissues. This is directly related to the speed of the object as it penetrates tissues, its shape, size and stability and the strength of the structures with which it comes into contact. Tissue along and, in the case of a high velocity injury, beyond the track of the wound will be damaged (Whiteside and Moorehead, 1999).
- Penetrating objects must only be removed in theatre where effective action can be taken to control serious bleeding (Melby and Deeny, 1994);
- If the wound can be thoroughly cleansed and all foreign bodies removed, it can be closed. Gunshot wounds, either high or low velocity, should never be treated by primary closure. They should be closed after three to seven days if there is no infection (delayed primary closure).
Shearing and degloving injuries
Classically, a shearing (twisting) force pulls the skin and subcutaneous tissue from underlying muscle or periosteum. Connecting blood vessels are ruptured and the skin dies. The injury commonly occurs when a ring on a finger gets caught in machinery or railings, or a limb gets trapped between a road surface and the tyre of a moving vehicle (Fig 8). A degloving injury should be suspected if there is any local evidence of pallor, loss of sensation, friction burn, tyre imprint or abnormal skin mobility.
- If there is hope of salvaging any of the tissue, the patient must be taken to theatre as a surgical emergency;
- All of the ischaemic skin is excised in theatre and the defect is usually covered with a split skin graft. It is sometimes possible to harvest the skin graft from the degloved segment of skin - primary reattachment of the skin usually fails (Whiteside and Moorehead, 1999).