Monday, July 29, 2013

Dog Bite Treatment


Dog bites can be traumatic and painful experiences that can leave both physical and emotional scars. However, as long as adequate, timely and appropriate treatment is given in the majority of cases the prognosis is excellent. Although there aren't any exact figures about 60-90% of bites are caused by dogs and between one third and a half of bites occur in children. In 70% of these cases the victims are bitten by their own dog or a dog they are familiar with. According to one report, in the UK, you are more likely to be killed by a lightening strike than you are from a dog attack!

First Aid for bites:

Before you begin to treat the victim make sure that the situation is safe for you and the victim. Make sure that the dog is not around by either taking the victim away or getting the owner of the dog to remove the dog and either chain it up or shut it up away from you. You should try to find out the name and address of the owner, the breed and immunization status of the dog if possible as this may be useful if further treatment or action is required.

Try to stop the bleeding but only use tourniquets as a last resort for severe bleeding that can't be controlled in any other way. If possible keep the injured part elevated above the heart to control the bleeding.

The mouth carries many bacteria which can cause infection in a wound so it is vital to clean the wound thoroughly with boiled, cooled water for 5-10 minutes. Running water is preferable otherwise soak the area in water that is frequently changed (you should wear gloves while you do this to protect yourself).

Don't apply antibacterial lotions on an animal bite as some bacteria in saliva can actually proliferate, or reproduce quickly in a short interval, in certain creams. Some may also damage the skin tissue and healing.

Apply direct pressure to the wound with a clean cloth. Dress the wound with a non-adhesive, sterile gauze and bandage. Watch for signs of infection, if they develop up to 48 hours after the bite you should see your doctor. Bites, by definition, break the skin which allows bacteria from the saliva in the animal's mouth to seep into the open wound and can result in infection. Antibiotic prophylaxis is normally given. Prophylaxis is a Greek word meaning an advance guard; in medical terms it means a measure is taken to maintain health and prevent the spread of a disease or condition.

If any parts are actually torn off during an attack (such as an ear) then you should wrap the part in clean tissue paper, store it in a plastic bag surrounded by ice and take it with you to the hospital.

Signs and symptoms of infection:


  • Pain around the wound

  • Redness

  • Tenderness

  • Swelling

  • Pus or discharge

  • Fever

  • Swollen glands


First Aid for infections:

The wound should be covered with a sterile bandage leaving the area surrounding it visible so that you can monitor signs of spreading. Try to keep the wound elevated and supported. See your doctor as soon as possible to prevent further complications.

The risk of infection is particularly high in punctures, hand injuries, full thickness wounds, those needing surgical debridement, and wounds involving joints, tendons, ligament and fractures. Also infections are more likely if the wound is deep or dirty, or if there is a lot of blood under the wound.

Certain factors make some people more vulnerable to infection:


  • Diabetes mellitus. (Increases the risk of Pasteurella infection)

  • Alcoholics. (Increases the risk of Pasteurella infection)

  • Cirrhosis or liver scarring.

  • People on steroid therapy. (Increases the risk of Pasteurella infection)

  • Rheumatoid arthritis. (Increases the risk of Pasteurella infection)

  • Lymphoedema after radiotherapy. (Increases the risk of Pasteurella infection)

  • Asplenia which is the absence of normal spleen function.

  • Wounds more than six hours old.

  • Devitalised tissue.

  • Previously sutured wounds.

  • Full thickness wounds involving tendons, joints or ligaments.

  • Bites on limbs especially the hands.

  • Those with compromised immune systems due to drugs or illness.

Pasteurella is a bacteria found in most animals. If a wound is infected by these bacteria then the wound becomes red and inflamed, this occurs rapidly: within 24 hours and there is significant pain and swelling. Occasionally it can cause pneumonia or other respiratory infections; very rarely it causes kidney infections or meningitis. If it is treated promptly with antibiotics then the prognosis is good. However if any infection is left untreated then it may spread to the bloodstream causing blood poisoning, or cause swelling, stiffening of the joints and tissue damage.

Complications:

Scarring. In children, dog bites frequently involve the face, potentially resulting in severe lacerations (cuts) and scarring.

Infections:


  • Such as tetanus, rabies, septicaemia, septic arthritis, tendonitis, peritonitis, meningitis and osteomyelitis which is infection of the bone.

  • Wound infection occurs in 2-30% of dog bites.

  • Infections from bites are polymicrobial, (more than one species involved) often including anaerobes which can survive without oxygen. Common bacteria include Staphylococcus, Streptococcus, Eikenella, Pasteurella, Proteus, Klebsiella, Haemophilus, Entrobacter, Capnocytophaga, Canimorsus and Bacteroides.

Fractures.

Disfigurement.

If you sustained the bite abroad then you may be at risk of rabies. At the moment the UK is largely free from rabies (although some bats carry the disease in the UK), but it is common in Africa, Asia, Central and South America and some cases have been reported in Eastern Europe. Rabies is a serious illness that can be fatal to humans so if you are bitten or scratched abroad you should seek immediate medical attention even if you don't think you have contracted anything-rabies is virtually undetectable in the early stages. You should contact the Health Protection Agency Centre for Infection or Health Protection Scotland. Staff will need to know:


  • Your previous vaccination status

  • The country where you were bitten

  • The site and date of the bite

  • Whether the attack was provoked or not

  • Whether it was a domestic or feral dog

  • The current health of the animal if this is known.

The treatment to prevent rabies developing is called post-exposure prophylaxis and it involves 1 dose of rabies immunoglobulin (this is a blood product which contains antibodies against rabies) and 5 doses of rabies vaccine. If prophylaxis is required, it is usually obtainable from these centres as is the rabies vaccine (which is injected into the muscle) and the human rabies immunoglobulin.

Hospital Treatment:

About one in five people who are bitten by a dog seek medical attention, of those only 1% require hospital admission.

Some bites can be particularly serious and require more attention than just first aid. Also injuries can be more extensive than they appear especially puncture wounds as these are small but deep and can damage tendons or joints. Wounds can be quite complex as bites can involve sheering forces: the dog embeds its teeth into your skin, you react by pulling away and the skin tears. You should see your doctor if:

the bite is on:


  • the hand,

  • the foot,

  • a joint,

  • a tendon,

  • a ligament

  • the scalp,

  • the face,

  • the ears,

  • the nose,



  • You require antibiotics; you will also usually need admitting to hospital.

  • You think an infection has developed or is likely to develop.

  • You have bleeding that doesn't stop after 15 minutes of direct pressure

  • You think you have a broken bone or nerve damage

  • You are not up date with your tetanus vaccine

  • You were bitten by a dog with unknown immunisation status

When you see a doctor they may ask for the following information:

- Breed of dog. This is particularly important as a bite from a larger dog is more likely to damage deeper structures such as tendons or bone.
-Health status of the animal
- Time and location of the event
- Circumstances (i.e. a provoked or unprovoked attack.)
- Location of the animal now
- Any pre-hospital treatment
- Any factors which are likely to compromise immunity such as HIV or steroid therapy
- Any recent antibiotics (if infection is present in a patient taking antibiotics then this may suggest the infection is caused by a resistant organism)

Your wound should be washed with a normal saline or drinking water to remove the dirt and bacteria. If the wound is contaminated then a 1% providone solution is used as it is better than saline. The providone is diluted so it is germicidal but not toxic to the tissues. If you have not been immunised against tetanus within the last 5-8years then a booster shot is usually administered. However contracting tetanus from a dog bite is rare.

Sometimes debridement is required which involves medically removing dead, damaged or infected tissue, either by surgical, mechanical, chemical or autolytic (self-digestion) means. Dead or damaged skin needs to be removed because it is an ideal place for infection to develop. Also debridement helps to remove any blood clots or foreign bodies that might be lodged in the wound. Cleaning the wound and debridement is more important than medication in many cases.

Once the wound has been properly cleaned then primary suturing (stitches) may be performed. This is particularly good for facial wounds as there is an excellent blood supply to speed up healing. Gaping wounds may need to be stitched, glued or held together with steri strips. Suturing can help to prevent scarring and improve the cosmetic outcome. However some wounds may be left open for a few days to ensure that they aren't infected before they are closed up. Delayed closure for 3-5 days is usually done in cases where the bite is on the hand, those with extensive crush injuries, wounds that need considerable debridement and wounds that are more than six hours old. During this time they should be covered with a sterile, non-adhesive dressing to prevent any more bacteria entering the wound and causing infection.

Antibiotics may be prescribed to prevent infection and should provide protection against Pasteurella bacteria, anaerobes and staphylococci. At first this may be given intravenously through a drip into a vein. Antibiotics are useful for:


  • All wounds after primary closure

  • Puncture wounds

  • Large wounds

  • Bites to the hand and wrist. Antibiotic prophylaxis significantly reduces the risk of infection in bites on the hand, but they may not be as effective for bites elsewhere.

  • Bites on the face

  • Crush wounds with devitalised tissue

  • Wounds that required surgical debridement

  • Wounds involving joints, tendons, ligaments or fractures

  • Dog bite injuries to genitals

  • High risk patients such as those with diabetes, those with compromised immune systems, splenectomy, those on chemotherapy, splenectomy, artificial heart valves, rheumatoid arthritis and those with prosthetic joints.

In mild infections co-amoxiclav is usually prescribed as a first line of treatment. However, antibiotics are not usually needed for bites that are 2 days old and aren't showing signs of infection: infection has normally developed by this time if bacteria are present.

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