Initial Assessment & Management
Approach
PPE: Depending on the nature of the wound, don appropriate personal protective equipment in case of blood splash.
Haemostasis: Most bleeding will stop with pressure but may need require haemostatic agents or tourniquet if vascular structures affected. If tourniquet required to control arterial bleed, then aim to evacuate to a higher level of care at the earliest safe opportunity.
Analgesia: Appropriate analgesia should be given in accordance with the analgesia guideline (link pending). Consider early infiltration with local anaesthetic or a field block to aid irrigation and severity assessment, but take care to check for sensation before undertaking any block and do not pass a needle through dirty or contaminated tissue.
Examine
Search for wounds and broken skin areas remembering that there may be multiple bites. Small areas of irreparably damaged tissue may be debrided in a forward location to facilitate approximation/closure and reduce scarring, and wound edges should be excised - a useful technique is to use a pen to outline the wound edges of deep (or potentially deep) bite wounds and then to remove the marked tissue, thus achieving an excision that is shallow but includes all wound edges.
Bite wounds may also need to be extended in order to fully visualise underlying structures. Remember that the skin moves freely over deeper structures, so for example an overlying skin injury and underlying tendon injury may cease to be aligned when the limb moves.
If extensive wound excision is needed then evacuation to a deployed emergency department will be required; complex debridement will require evacuation for specialist plastic surgical review.
Check for damage to underlying structures:
- Vessels – Haemorrhage can normally be controlled with direct pressure. Only if control cannot be achieved by other means should a vessel be tied off using suture around the vessel.
- Tendons – If there is either visible damage to a tendon or loss of tendon function then the patient will require evacuation for plastic surgery.
- Tendon sheath damage – If tendon sheath breach but without visible tendon injury or loss of function, this can be managed with thorough wash out and antibiotics. Ideally this would be undertaken in a surgical facility, but could be managed in a forward location if evacuation is difficult or impossible.
- Breached nail – be aware that injuries in which the nail has been breached may include an underlying tendon injury: examination of such injuries, and indeed all hand injuries, should include careful assessment of tendon function; if there is evidence of tendon injury then evacuate for plastic surgery assessment.
- Foreign bodies (including teeth) – All small foreign bodies not lodged in major vessel should be removed from the wound. Be prepared to deal with increased bleeding upon removal. Transfer for imaging if concern of non-visible foreign bodies such as glass fragments.
Assess neurovascular status – Check nerve distributions for sensation in area of concern. Check distal pulses and capillary refill time. Any neurovascular compromise is an indication for time-critical surgical intervention.
Examine for bony tenderness – bony tenderness, crepitus or deformity may indicate an underlying bony injury which will require evacuation a facility with imaging capabilities. In the context of a bite, treat any such injuries as an open fracture including antibiotics as per the antimicrobial guidance (link pending).
Check range of movement – for any bites to a limb or adjacent to a joint, check the range of active and passive movement of any joints involved, assessing ligament and tendon function.
Bites to the face - in addition to the above, check for occlusal injury and damage to the periodontium (the tissues surrounding and supporting the teeth). Perform intraoral examination to exclude cheek lacerations that may be have intraoral communication.
Signs of infection – assess carefully in delayed presentations; record baseline observations if concerned about systemic involvement and following guidelines for the immediate management of sepsis (link pending) if sepsis is suspected or identified.
Irrigate
Thoroughly irrigate the wound with at least 1L of normal saline or running clean water to minimise bacterial contamination. Use warm fluid if available.
Encourage the wound to bleed whilst irrigating, unless bleeding freely already.
Directed irrigation can be used by attaching a cannula (largest cannula size available, with needle removed) to the end of a giving set and fluid with the fluid hung up allowing irrigation under low pressure. This allows irrigation deep into the wound where needed.
Wounds at high risk for rabies may benefit from washout with povidine iodine which is likely to only be available in deployed hospital facilities. In such cases, the patient should therefore be evacuated if possible back to a hospital facility for specialist assessment and further washout.
Imaging
As above, patients will need to be transferred to a facility with imaging capabilities (X-ray and/or ultrasound) if there is suspicion of an underlying fracture, and additionally if there are suspected or confirmed retained foreign bodies, or features of deep-seated infection.
Antibiotics
Antibiotics should be prescribed to all human and animal bites that occur in the deployed environment, in accordance with the current antimicrobial guidance (link pending).
Wound Closure
Avoid primary closure of contaminated wounds: any wound from a bite should be treated as contaminated, but other wounds such as scratches only need to be treated as contaminated if there is gross environmental contamination.
In contaminated wounds irrigate thoroughly and if unable to evacuate to see plastic surgeon then undertake delayed primary closure after 48hrs or allow secondary intention healing. Seek to reach back for specialist advice in these cases.
Sutures should only be used to close contaminated wounds if it is impossible to otherwise cover vital structures such as critical vessels or named nerves. Placing a suture in a wound that is infected adds foreign material and reduces the opportunity for infected fluid to drain. Only if unavoidable, use a large suture to approximate wound edges only after thorough washout, tying loosely to allow drainage of serous or infected fluid.
Cautions:
- Avoid using glue to close bite wounds.
- Do not close puncture wounds. Allow healing by secondary intention in these cases.
- Do not close wounds from cat or human bites - allow healing by secondary intention in these cases, unless the wound is on the face, in which case enhanced perfusion means that infection is much less likely so wound closure may be attempted to improve cosmesis.
- Avoid attempting to close wounds if the patient is immunocompromised. These patients should be evacuated to a facility with surgical capabilities for washout and debridement.
Consider wound closure in a forward location for simple wounds with no underlying infection or structural damage if the wound is either <24 hours old on face (to reduce cosmetic impact) or <12 hours old elsewhere.
Generally use interrupted sutures as this will allow drainage of any pus that may build-up rather than collecting within the wound. If this is anticipated to give an unsatisfactory cosmetic outcome then consider evacuation to a facility with surgical capability.
Dressing
Use sterile, non-adherent dressings. Consider limb elevation if appropriate.
Evacuation
If able to evacuate then refer complex, infected, or high-risk bites (such as cat bites, bites to the face or hands) to plastic surgery for further evaluation. If unable then reach back for specialist advice can be used to seek any further advice.
Prophylaxis
Rabies: see additional information below.
Tetanus: all deployed Service personnel should be fully immunised and will therefore only require prophylaxis for high-risk wounds; see guidance on tetanus-prone wounds (link pending) for information on how to manage this and how to treat patients who are not immunised or whose immunity is uncertain.
Blood-borne viruses: follow guidance on needlestick and inoculation injuries (link pending) for patients who have sustained a human bite.
Advanced Assessment & Management
The assessment and management of bite injuries in the deployed Emergency Department will be similar to that outlined above.
Complex, infected, or high-risk bites (such as cat bites, bites to the face or hands) should be referred or discussed with plastic surgery for specialist advice.
Prolonged Casualty Care
Patients with bite wounds who require evacuation but in whom this is delayed should continue to receive antibiotics regularly in accordance with antimicrobial guidance.
Change dressings regularly in order to maintain a clean and dry environment around the wound.
Sutures should only be used to close contaminated wounds if it is impossible to otherwise cover vital structures such as critical vessels or named nerves. Placing a suture in a wound that is infected adds foreign material and reduces the opportunity for infected fluid to drain. Only if unavoidable, use a large suture to approximate wound edges only after thorough washout, tying loosely to allow drainage of serous or infected fluid.
Paediatric Considerations
Increased Infection Risk: Recognise that young children have a heightened susceptibility to infections. All patients with an open wound from a bite should be treated with antibiotics.
Emotional Impact: Provide reassurance and involve parents.
Bite Location: Paediatric bites frequently occur on the head, neck, and face, requiring specialised assessment. Children may require procedural sedation to facilitate wound closure. Sedation is covered in a separate guideline.
Vaccination Status: Confirm up-to-date tetanus vaccinations and consider rabies prophylaxis when indicated.
Reporting & Safeguarding: Examine cases of animal bites in children for potential neglect or abuse, and report accordingly when suspicion arises.
