Scorpion Sting

Question 1

Scorpion venom composition and effects

Answer 1

• Scorpion venom is a potent autonomic stimulant resulting in a sudden pouring of endogenous catecholamines and ACh into the blood stream.
• The massive release of these mediators in the circulation results in a severe autonomic storm.

Question 2

Clinical picture 1-Local

Answer 2

Local
Intense local burning pain
Numbness and tingling in the area around the sting
Erythema, local edema, and sting marks are not common

Question 3

Clinical picture 2-Systemic

Answer 3

Systemic
1-General: Fever, Sweating and dehydration, and cold extremities, Priapism
2-Cardiovascular: Tachycardia, Hypertension (severe, very characteristic of scorpion envenomation), Dysrhythmias, Acute heart failure and shock in severe cases.
3. Respiratory: Tachypnea, respiratory distress and failure, stridor, wheezes and crepitations, Acute pulmonary edema (which type??).
4. Neurologic: Agitation, tremors, convulsions, coma, Restlessness
5. GIT: Excessive salivation, vomiting, diarrhea
6. Metabolic effects: Hyperkalemia, stress hyperglycemia and metabolic acidosis.

Question 4

What are investigations to do?

Answer 4

1-Laboratory: CBC, RFT , Coagulation studies, S.electrolytes, Blood sugar test, ABG
2-ECG
3-Chest x ray: Pulmonary edema may be cardiogenic or non cardiogenic)

Question 5

Management

I. First aid (pre-hospital care)

Answer 5

Ice pack
Immobilization of limb
A local anaesthetic is injected at site of pain

Question 6

Management

II- Emergency measures:

Answer 6

ABCD

• Control convulsions (by Diazepam, barbiturates)
• Treat Shock , pulmonary edema, cardiac, and respiratory failure

Question 7

Management
III. Antidote: scorpion antivenom
Indications

Answer 7

Indications: it is given to all children and senile adults presenting with any of the systemic manifestations as well as patients with previous cardiovascular disease, hypertension or diabetes.
Dose: 3 vials IV over 10 min after reconstitution. Additional 1 vial may be administered IV every 30-60 min. as needed for symptoms control.
Dose in children equals adult dose.

Question 8

Management

IV- Symptomatic treatment

Answer 8

• Pain is treated by NSAID drugs or local infiltrative anesthesia
• Hypertension is treated by vasodilators, in particular prazocin, sodium nitroprusside, nifedipine and captopril
• Cholinergic manifestations: are treated by atropine as anticholinergic drug.
• Vomiting is treated by antiemetic drugs
• Hyperpyrexia is treated by anrtipyretics (paracetamol) and cold compresses
• Heart failure is treated by dobutamine
• Dehydration is treated by IV fluids