Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

Because the spine is coated with a sheath of tissue that contaminates the wound, infection is likely. Treatment includes spine or stinger removal and aggressive wound debridement. Most types of spiny toxins are inactivated by heat. Immerse the affected part in water as hot as the patient can tolerate until pain is relieved. Often this will be within a few minutes, but treat- ment may need to be continued for an hour or more.

nematocysts of some species and is specifically recommended for box jellyfish, fire worm, and sponge stings. There is also evidence that hot water soaks, as with spiny envenomation, or even a hot shower may reduce the pain immediately after the sting, although the mechanism is not well understood. Ice applications may help relieve persistent pain later. The use of alcohol, meat ten- derizer, urine, or other chemicals to flush the skin is not helpful, and possibly harmful.

Spiny Injury

General Principles

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Treatment: • Immerse extremity in hot water up to 90 minutes • High-risk wound care, anticipate infection • BLS/ALS and immediate evacuation for progressive neurologic symptoms (lionfish, stonefish, cone shell) • Pain control Typically tissue toxin, sometimes combined with neurotoxin

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© 2018 WMA

Nematocyst Sting Nematocysts are structures in the stinging parts of jellyfish, corals, and anemones, that fire some- thing resembling a microscopic harpoon when touched. These harpoons inject a potent neu- rotoxin into the skin. Individually, the amount of toxin is miniscule but the toxin load can be considerable when the patient has contact with thousands of nematocysts at once. Toxin load is the term applied to the cumula- tive effects of multiple stings or bites. Of particular concern are stings from the Indo-Pacific box jel- lyfish (Chironex fleckeri), due to the high potency of the venom, and the Portuguese man-of-war (Physalia physalis), due to the potential for large surface area exposure. The field treatment for stinging jellyfish includes removing tentacles by flushing with seawater and picking off any remaining tentacles with forceps or gloved fingers. Seawater is considered by some authorities to be preferable to fresh water because the osmotic difference of fresh water may stimulate more nematocysts to fire. Flushing and soaking the skin with vinegar will inactivate the

The long tentacles on jellyfish carry the potential for large surface area stings. Persistent skin inflammation can be treated for several days with twice daily applications of a steroid cream or ointment (e.g., hydrocorti- sone). Antihistamines may also help because a local allergic reaction may be part of the patient’s discomfort. As with any open wound, infection is an anticipated problem.

Nematocyst Injury

General Principles

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Treatment: • Rinse with salt water, remove tentacles • Hot water soaks • General wound care, topical corticosteroids and topical anesthetics • BLS/ALS and immediate evacuation for progressive neurologic symptoms (box jelly, man-of-war) • Pain control

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© 2018 WMA

Systemic effects from large or potent exposure to nematocyst-borne neurotoxins include pain,