Bites

SNAKE BITE

Snakes are reptilians, which inhabit forests, and dark and cold places. They come out during the monsoons and during this time the chances of snakebites increase. Rural areas have more rates of snakebites than the urban areas.

Snakes can be poisonous or non-poisonous. The poisonous snakes include
  1. Cobras
  2. Kraits
  3. Vipers
  4. Sea snakes

The severity of the bite depends upon the following factors
  1. Amount of the venom injected.
  2. Whether the bite was through clothing.
  3. The angle at which the bite was given.
  4. The status of the glands of the snakes.

CLINICAL FEATURES : Parents or guardians come forth with history of snake or unknown bite. The parents or neighbours may bring the killed snake. The child may have fang marks. There may be local swelling, edema, redness, pain and purpuric areas with tenderness. The patient may be anxious and irritable.

There are three types of poisons

• Neurotoxic- from cobra bites. The patient has altered sensorium, convulsions, ptosis, bulbar palsies, coma, and respiratory paralysis.
• Vasculotoxic- The vipers release toxins like hemolysins, proteases, hyaluronidases etc., which cause the local swelling and coagulation defects. There will be bleeding from the body orifices and petechiae on the skin. Local ecchymotic patches will be seen in and around the bite area. The child enters into disseminated intravascular coagulopathy and shock.
• Myotoxic- Sea snakes have a myotoxic action. There is a lot of pain at the site of the bite and myalgia. The patient may have myoglobinuria (passage of the myoglobin from the muscles into the urine). Besides renal failure due to this may be seen.

TREATMENT :
• The parents of the child with snakebite are very worried about the outcome. The child if old enough also may be tense. Hence reassurance should be given to them.
• The clothing of the child should be loosened and he must be allowed fresh air.
• Tourniquet may be applied above the site of the bite over a single bone. It should be loosened in between every 10 minutes for 15-30 secs. The tourniquet should not be tight enough to occlude the arterial supply but only the lymphatic and venous drainage.
• The limb should be immobilized and kept elevated. Magnesium sulphate dressings help in early reduction of edema. Ice packs may also be used.
• Sucking of the poison from the wound is controversial and is best avoided.
• Give the patient cardio respiratory resuscitation if there is difficulty in breathing.
• Shift the patient to the hospital immediately.
• Take the killed snake to the hospital if possible for identification.

DOG BITE

Dogs are no doubt faithful animals. They are kept as pets in the house. But in the city and urban areas, they are seen moving around in a stray manner. These are dangerous as they could be carrying the rabies virus, which can be transmitted to the humans by the bite of such a rabid dog.

The history of bite is forthcoming. The patient may cry in pain and also panic due to the fear of rabies. Rabies does not come immediately and is not invariable with dog bite. The dog has high likelihood of rabies if it has bitten a number of other humans, it has bitten without provocation and if dies within 10 days of biting an individual. Hence an observation of the dog, which has bitten an individual, is of utmost importance for atleast 10 days.

The signs of rabies in humans are seen after an incubation period of few months. There is headache, nausea and vomiting. The patient is confused and agitated. Difficulty in swallowing is noticed with frothing at mouth. There is hydrophobia. Patient becomes lethargic and has respiratory paralysis.

Treatment : The patient should be reassured. The bitten part should be washed with soap and free flowing water. Patient should be taken to the hospital for wound dressing, injection tetanus toxoid and post-exposure anti-rabies prophylaxis.

Stings

This is an acute, life-threatening medical emergency, which is most common in the villages and crowded urban areas. The true incidence is not available but the case fatality rate is around 3-22%. Warm and arid areas abound in scorpions. They live in the crevices and underground burrows. Banana and sugarcane fields have scorpions in them. The stings are usually accidental.

There is severe and excruciating local pain. Irritability occurs. There may be vomiting, ill feel, sweating, salivation. The heart rate may be increased or low. Blood pressure is usually high. Shock is also reported. Death is usually due to pulmonary edema. In children, erection of the penis (priapism) may be noticed. Rarely convulsions may be seen. Stroke, central type of respiratory failure and altered sensorium has been rarely reported.

The victim needs reassurance. The clothing should be loosened. It is preferable to keep the patient nil by mouth and a simple pain relief like paracetamol may be given but its utility is limited. Local lignocaine may be given. The patient should be shifted to the hospital immediately in order to prevent complications and also the outcome is improved with early therapy with Prazosin.