Envenomation

Question 1

Coral snake bite

Answer 1

• Even bites that appear to have minimal local effects may have devastating systemic consequences. This is more likely after a coral snake bite than any other type
• The patient may develop slurred speech, fasiculations, drowsiness, weakness, and trouble breathing.

Question 2

How does the venom from coral snakes work and what is the usual cause of death?

Answer 2

• The cause of death in these cases is usually progressive paralysis of the respiratory muscles.
• Blocks Acetylcholine receptors

Question 3

Pit viper bite

Answer 3

• Will initially have localized edema and pain
• After a few hours, vesicular lesions and bullae, often hemorrhagic, may develop
• The systemic signs nausea, weakness, muscle fasiculations, changes in taste sensation (metallic), and sensory changes, involving the mouth, fingers, and toes.

Question 4

How does the venom from pit viper snacks work and what is the usual cause of death?

Answer 4

• Viper bites disrupt the coagulation cascade and alter vascular permeability.
• This may ultimately lead to pulmonary edema and refractory shock. Some pit vipers also cause neurotoxicity and respiratory failure.

Question 5

Spider bites are often unseen, therefore need to know the Toxidrome. Black widow spider

Answer 5

• Neurotoxic. Pain (local, radiating, regional) that increases over the course of an hour and may radiate proximally along the affected limb to the trunk. Then muscle spasms.
• Systemic effects less common.

Question 6

brown recluse spider

Answer 6

Bites can vary from mild, self-limiting erythema to large, necrotic ulcerations. Local pain and burning are common. Systemic symptoms are rare, but may include hemolysis, disseminated intravascular coagulation and renal failure.

Question 7

Scorpion sting

Answer 7

urning pain, pruritus and paresthesias at the site of the sting. Severe systemic symptoms of the Arizona bark scorpion include catecholamine (restlessness, coma, and convulsions) and cholinergic effects (bradycardia, hypotension, salivation, lacrimation, and diarrhea).

Question 8

Jellyfish Sting

Answer 8

Jellyfish leave linear sting contact marks, occasionally in a cross-hatched pattern

Question 9

Stingray Sting

Answer 9

In addition to localized pain, bleeding, and erythema, systemic symptoms such as hypotension and shock, may occur.

Question 10

Initial treatment of a venom injury

Answer 10

The affected extremity should be immobilized and slightly compressed, to prevent the spread of venom.
- NO tourniquet though.

Question 11

When should anti-venom be used for snake bites?

Answer 11

In general, any patient who displays moderate to severe signs and symptoms after a venomous snake bite is a candidate for treatment. Antivenom indications include increased swelling and erythema beyond the local bite wound and any disruption of the coagulation cascade. If a coral snake bite is suspected, the patient should immediately receive antivenom, even before the onset of symptoms

Question 12

When should anti-venom be used for spider bites?

Answer 12

Less common to use. Antivenom indications include increasingly severe pain, proximal spread of muscle spasm/rigidity, increased sweating and hypertension. Antivenom is not used routinely for spider envenomations in the United States because of concern for anaphylaxis.

Question 13

What should you monitor for after giving anti-venom?

Answer 13

Anaphylaxis. Also, delayed serum sickness and its associated symptoms.

Question 14

Treatment for sting ray and jelly fish

Answer 14

Local symptoms may require analgesia or a regional nerve block. Most jellyfish stings should first be treated by inactivating the nematocysts with vinegar or acetic acid. Submerging the affected area in hot water provides effective analgesia as well. Stingray envenomations should be soaked in very hot water as soon as possible

Question 15

Describe the muscle rigidity seen with a black widow spider bite

Answer 15

• The muscle rigidity of black widow spiders may be severe. If it involves the abdominal musculature, the envenomation may be mistaken for an acute abdomen.
• ***To distinguish the two, abdominal rigidity associated with a black widow spider will have little or no associated tenderness.

Question 16

When can a patient be cleared after a bite?

Answer 16

As a general rule, if there are no symptoms within six to eight hours, the patient can be considered medically cleared.

Question 17

When should you admit a patient?

Answer 17

All coral snake bites require admission for observation.

If you gave anti-venom

Question 18

How do scorpion stings venom work?

Answer 18

contains neurotoxin that increases sodium channel permeability resulting in sodium channel activation and cell membrane depolarization. This results in over-stimulation of sympathetic and parasympathetic nervous systems, causing excessive acetylcholine and catecholamine release.

Question 19

Scorpion sting presentation

Answer 19

The patient often presents with severe sensitivity to touch at the site (tap sign). Numbness, tingling, anxiety, nausea/vomiting, and blurred vision are common findings. Characteristic signs of envenomation include hypersalivation, abnormal roving eye movements (chaotic multidirectional conjugate saccades), fasciculations, and clonus. Hyperthermia, hypertension, tachycardia and excessive respiratory secretions are consistent with a cholinergic syndrome. Mental status is typically preserved. Depending on the severity of envenomation, patients can ultimately develop dysrhythmias, catecholamine-induced myocarditis, myocardial ischemia and cardiopulmonary arrest.

Question 20

What separates a scorpion sting from a black widow sting?

Answer 20

Scorpion stings have severe pain at site. Black widow stings may have lymphadenitis and diaphoresis at the site.

Question 21

When should anti-venom be used for a scorpion sting?

Answer 21

Antivenom (Anascorp®, US; Alacramyn®, Mexico) should only be considered when there is severe somatic or cranial nerve dysfunction not controlled by supportive measures.

Question 22

What is the poison control number?

Answer 22

1-800-222-1222.

Question 23

Cholinergic crisis

Answer 23

Cholinergic Crisis: Patients can present with cholinergic symptoms, especially excessive oral secretions. Atropine has been reported to be helpful in managing these symptoms. However, atropine should not be routinely used and should only be administered to patient who develop severe cholinergic crisis. The benefits of atropine must be weighed against the risk of tachycardia and dysrhythmias.