Wounds
Wounds often involve visible areas, the face and upper limb, where
cosmetic as well as functional outcome is important. Wounds are generally incised
– caused by sharp objects, or lacerated – caused by blunt force. An abrasion
is a wound where the upper layers of the skin are removed, but there is no
surface break. A wound where the depth exceeds the width or length is described
as a puncture wound.
Resuscitation
Bleeding
should be stopped using direct pressure or tourniquets: blind clamping should
be avoided. Bleeding from scalp wounds can be controlled by full-thickness
sutures using 2/0 nylon.
Any wound
near a fracture is assumed to communicate with it, and should be covered by a
clean saline-soaked dressing and anti-biotics administered immediately.
Toxic bites
(e.g. from snakes, spiders) should be treated accord- ing to local protocols.
Snake bites can be painless, and venom may cause paralysis or catastrophic
anticoagulation. Antivenom derived from animal serum is quite toxic in itself,
so should not be given unless toxicity is certain.
History
Medical
notes from the Emergency Department are used to write legal reports: avoid
words like ‘cut’ or ‘stab wound’ unless you are an expert. Unless you witnessed
the injury, use ‘alleged’ and quote the patient’s own words wherever possible,
e.g. ‘Alleged assault – patient says was “hit with bottle outside a
nightclub”.’ Accurate descriptions with measurements, diagrams and
photographs are very helpful. Occupation/hobbies, hand dominance, allergies and
tetanus status should be recorded.
Examination
Look Assess skin loss and
viability, contamination, cut muscle or crush injury.
Feel Test motor and sensation
(before local anaesthetic infiltration).
Move Test muscle and tendon
and muscle function while observing the wound. If the wound is very painful,
this is best done after infiltration of local anaesthetic.
Foreign body
Examination
cannot reliably exclude foreign bodies (FBs), which are common in motor vehicle
accidents, puncture wounds and clenched fist injuries. Imaging is not necessary
for most wounds; X-ray if the FB is radio-opaque, i.e. metal or most glass.
Ultrasound is useful, but is operator dependent.
Management
Assess the wound
Is the wound
complex or dirty?
•
Complex: the wound is large, involves crushed tissue, FBs, injection
under pressure or extends into deep structures like muscles, tendons or joints.
These wounds have a high risk of infection or compartment syndrome (Chapter
15).
•
Dirty: if there is obvious contamination or the wounds is >6
hours old.
Patients with reduced immune function (e.g. diabetes, steroids) are at
increased risk of infection.
Consider the
reason for the wound (e.g. fall, domestic violence), and any other potential
injuries.
Is it safe to close the wound in
the Emergency Department?
All complex
or obviously contaminated wounds should be referred for exploration and closure
in an operating theatre.
The options
for wound closure are:
•
Primary closure – close the wound immediately. This gives the neatest
scar, but risks infection by trapping bacteria within the wound.
•
Delayed primary closure – clean, give antibiotics for 48 hours, then
close. This reduces the risk of infection in dirty wounds.
•
Secondary healing – allow the wound to heal on its own. It heals more
slowly, and there is more risk of scarring.
Analgesia
Local
anaesthetic (LA) is injected around wounds to allow thorough cleaning and
suturing (Chapter 5). Lidocaine1% ±
adrenaline (epinephrine) 1 : 100 000 is the most commonly used LA. Pain on LA
injection is reduced by using a small needle, warming the LA and injecting
slowly through wound edges. For wounds to be glued, use topical lidocaine
with adrenaline applied onto a piece of gauze, cover and leave for 20 minutes.
Clean the wound
A tourniquet
can be used to ensure a bloodless field. Hair near a wound may need to be cut
or shaved, but not eyebrows or eye-lashes. Use a syringe and 19 G needle and
drinking-quality water to irrigate the wound under pressure: guard against
splashback by wearing a mask and eyewear. Remove non-viable tissue and ensure embedded
grit is removed to prevent tattooing.
Close the wound
Sutures
Interrupted
non-absorbable nylon sutures allow drainage and minimise tissue tension and
ischaemia. If there are potential spaces within the wound where a haematoma
could form, or there would be tension on the skin sutures, deep absorbable
sutures (e.g. polygalactin/polyglycolic acid) are used.
Timing of
suture removal is a balance between scarring (shorter time better) and wound
strength (longer time better). For facial wounds, 5 days is best; for wounds
over extensor surfaces of joints, 14 days.
Glue, adhesive strips, staples,
dressings
Tissue glue
(similar to domestic Superglue®) or adhesive strips are effective for simple
wounds, providing the wound edges are easily opposed without tension. The
effectiveness of adhesive strips is increased by pre-coating the skin with
Friar’s Balsam. Staples are a fast way of closing linear wounds that do not
need a perfect cosmetic result, especially scalp, limb or self-harm wounds.
If the wound
is dry, a clear vapour permeable dressing allows inspection. If there are
exudates, a dressing that is absorbent yet non-adherent is preferable.
Tetanus, antibiotic prophylaxis
Wounds that
are dirty or complex are prone to tetanus. If a patient has had full tetanus
immunisation, further boosters are not necessary unless the wound is heavily
contaminated, e.g. with soil), in which case tetanus immunoglobulin is given.
Antibiotics
are not a substitute for adequate wound cleaning. Antibiotics are indicated in
wounds at high risk of infection or with established infection: flucloxacillin
covers Staphylococcus and Streptococcus.
Special situations
Bites
Bite wounds
from humans or animals are prone to infection due to the combination of crushed
tissue and inoculation with saliva. Wounds should be cleaned and 5 days of
broad-spectrum antibiotics (e.g. co-amoxiclav) prescribed.
Needlestick
Wounds that
risk hepatitis or HIV transmission should be thoroughly cleaned. Blood should
be taken and local policies consulted about follow-up.
Pre-tibial lacerations
Elderly
patients can tear the thin skin over the anterior tibia. The skin should be
stretched to cover as large an area as possible and early plastic surgery review
arranged.
Facial wounds
Facial
wounds are closed up to 24 hours after injury as cosmesis is important, and the
excellent blood supply provides some protec- tion against infection. Antibiotic
ointment can be used instead of systemic antibiotics.
