Events Surrounding the Injury

Timing of the Injury
It is best to close an open wound within 6 hours of injury. Do not close
a wound after 6 hours because the risk of infection becomes unacceptably
high.
Wounds on the face are exceptions to this rule. The face has an excellent
blood supply, which makes infection less likely. In addition, cosmetic
concerns are important. It is therefore acceptable to close a
wound on the face that is older than 6 hours (perhaps up to 24 hours or
at most 48 hours), as long as you can clean it thoroughly.
Nature of the Injury
• A wound caused by a clean knife has a low risk of infection.
• Adirty wound carries a risk for tentanus. Wood may break off and
leave pieces behind, increasing the risk for subsequent infection if
the wound is not explored and washed out thoroughly.

• Any wound that may contain a foreign body should be explored and
the foreign body removed.
• Animal bites, especially cat bites, often penetrate more deeply than
you think. Bites on the hand should raise concern about involvement
of an underlying joint. Oral bacteria may cause severe infections (see
chapter 36, “Hand Infections”). Always consider the risk of rabies.
• Human bites also are associated with specific oral bacteria that may
cause serious infections (see chapter 36, “Hand Infections”).
• If any object penetrated the patient’s clothing or shoes before piercing
the skin, the chance for infection is increased because pieces of
clothing may become embedded in the underlying tissues. If an
object penetrated the patient’s tennis shoes, be concerned about a
possible pseudomonal infection.
• Crush injuries may be associated with greater underlying damage
than initially appreciated (see chapter 35, “Crush Injury”).
• Gunshot wounds: see chapter 37, “Gunshot Wounds.”
• Thermal or electrical injury: see chapter 20, “Burns.”
Concerns about Tetanus
Table 2. Risks for Tetanus


Concerns about Rabies
Be aware of the risk of rabies in the area where you work. Some countries—
England, for example—have no cases of rabies because of tight
animal controls. In most other countries, rabies is a real concern.
The primary animals associated with rabies infections include bats,
raccoons, skunks, and foxes. Because different areas have a different
risk for specific animals, know your area. Dogs and cats also can be infected;
be sure to ask if the animal has been vaccinated against rabies.
Livestock, rodents (e.g., rats, mice, squirrels), and rabbits are almost
never associated with a risk of rabies.

If you have fears that the animal is rabid:
1. Thoroughly clean the wound with soap and water.
2. Administer human rabies immunoglobulin, 20 IU/kg total. If possible,
administer one-half of this around the wound, and give the rest
in the gluteal area intramuscularly (IM).
3. Administer one of the three types of rabies vaccines currently available:
1.0 ml IM in the deltoid area of adults and older children, outer
thigh (not gluteal area) in younger children. Repeat on days 3, 7, 14,
and 28.

About the Patient

Tetanus Immunization Status
Tetanus is a devastating disease, causing muscle spasms that can lead
to muscle rigidity and seizures. Without adequate treatment, one in
three adults with tetanus will die. Although immunization has made
tetanus uncommon, it always lurks in the background.
If the patient has not had a tetanus booster within 5 years, and the
wound is tetanus-prone (see Table 2), a booster should be given. If the
wound is not tetanus-prone but the patient has not had a tetanus
booster within 10 years, a booster should be given. Patients who have
never been immunized need human tetanus immunoglobulin as well as
tetanus toxoid followed by completion of the full tetanus toxoid series.


Note: Tetanus toxoid and immunoglobulin must be kept refrigerated at
all times during transport from the factory. This requirement may be a
problem in remote areas.
Pulsatile Bleeding at Time of Injury
Even if the patient is not bleeding at the time of your examination, the
history of bright red, pulsatile bleeding at the time of injury implies an
arterial injury. Athorough vascular exam is required, and formal surgical
wound exploration is almost always indicated.
Medical Illnesses
Patients with diabetes are more prone to infections and wound-healing
problems. Encourage diabetic patients to keep glucose levels well controlled
to decrease the risk of complications. Malnourished patients
and patients with human immunodeficiency infection (HIV) or a history
of cancer also have wound-healing difficulties.
Smoking History
Tobacco smoking dramatically decreases circulation to the skin and
slows down the wound-healing process. Medical professionals have a
duty to tell all patients not to smoke. But the patient with an open
wound should be specifically warned that smoking interferes with and
perhaps prevents the healing process. Smoking also increases the risk
for wound complications and poor cosmetic outcome.

EVALUATION OF AN ACUTE WOUND

KEY FIGURE:
Irrigating a wound


This chapter explains the basics for evaluation and treatment of an
acute wound. Proper evaluation helps to determine the appropriate
next step—formal wound exploration or wound closure.
The first step is to control blood loss and evaluate the need for other
emergency procedures (see chapter 5, “Evaluation of the Acutely
Injured Patient”). The second step is to obtain a thorough history
about the patient and the events surrounding the injury.