Wound
excision
The most important step in the management of
any untidy wound is wound excision. This process is sometimes called ‘wound
toilet’ or ‘debridement’. The former implies washing and the latter laying
open or fasciotomy, all of which may be important in wound management but do not
describe excision of devitalised tissue which is the most important process. For
this reason the term ‘wound excision’ is preferred. In order to excise a
wound adequate anaesthesia — local, regional or general must be provided.
Where possible a bloodless field also aids identification of structures. For
superficial wounds the use of local anaesthetic with 1 in 200 000 adrenaline
gives good haemostasis of skin edges. In the limbs a pneumatic tourniquet is
used. It is helpful to use a skin marking pen to plan the skin excision and any
wound extensions. Excision should proceed in a systematic fashion dealing with
each tissue layer in turn, usually starting superficial and moving deep.
Longitudinal structures such as blood vessels, nerves and tendons are identified
and exposed, but left incontinuity. With experience the surgeon learns to
recognise dead tissues. Devitalised dermis is pink rather than white;
devitalised fat is pink rather than yellow; devitalised muscle is a dark colour,
has lost its usual sheen and turgor, and does not twitch when picked up with
forceps. Bone fragments with no soft-tissue attachment or nonvital soft tissue
attachments are also discarded. This approach to radical wound excision is
sometimes called a ‘pseudotumour’ approach, because the entire wound is
excised with an appropriate margin back to healthy tissue (Fig
3.8 and Fig 3.9). At
the end of wound excision the wound should resemble an anatomical dissection.
Normal bleeding should be observed from each layer. Occasionally in very
extensive wounds this radical approach must be modified. Where radical wound
excision would threaten the viability or function of the limb it is reasonable
to excise what is definitely nonviable, carry out fasciotomy as appropriate and
dress the wound, with a view to returning 48 hours later for a second look, and
thereafter further serial wound excisions until a tidy wound is achieved.