Lionfish Stings: Treatment and Prevention

Derek B. Covington, M.D.

Resident Physician – PGY2

Department of Anesthesiology

Technical Diving International - Instructor Candidate

Why should I Care?

Painful

Why Should I Care?

Deadly

Why Should I Care?

Tasty

Objectives and Outline

• To properly identify lionfish

• To recognize symptoms of an envenomation

• To treat an envenomation in the field

• To prevent an envenomation

Lionfish• Belong to family of fish called

Scorpaenidae– 3 genus: categorized based on venom organ

structure and toxicity• Pterois

– Long, slender spines w/ least potent sting– Lionfish

• Scorpaena– Shorter, thicker spines w/ more potent sting– Scorpionfish

• Synanceia– Stout, powerful spines w/ most potent sting– Stonefish

Scorpaenidae

Pterois SynanceiaScorpaena

www.stinapa.org, http://www.scubatravel.co.uk/e_Scorpion_fish_26_06.html, http://www.jamesfreeanimals.com/2012/04/stone-fish-what-do-you-know-about-this.html,

Scorpaenidae• Spines

– Number and location• 12-13 dorsal spines• 2 pelvic spines• 3 anal spines• Pectoral spines vary in number and are innocuous

– Each spine associated with pair of venom glands– Integumentary sheath surrounds spine and is

pushed downwards onto venom glands to stimulate venom during a sting

Lionfish

http://rollingharbour.com/tag/pterois-miles/

Venom

• Toxicity secondary to proteins– Proteins

• Antigenic stimulate the immune system• Large high molecular weight• Heat labile denatures at high temperatures

Lionfish

• Scientific name: Pterois volitans

• Venomous marine fish native to Indo-Pacific

• Characterized by red, white, and black bands with extravagant pectoral fins and dorsal spines

• Measure 6 to 4cm in length

• Weigh up to 500 grams

Lionfish

• Lifespan: 5 – 15 years

• Prey: small fish, invertebrates, and mollusks

• Predators: few natural predators include moray eels, large fish (Tiger groupers), and sharks.

Epidemiology

• Number of envenomations unknown– >100 in medical literature from aquarists– Typically involve divers, fisherman, and others

involved in marine activies

Mortality and Morbidity

• Severity of envenomations increase from Pterois to Scorpaena to Synanceia

• Lionfish– Typically local wound– May progress to tissue necrosis– Rare case reports of death

Symptoms• Immediate, excruciating to incapacitating,

local wound pain– Pain may spread to involved entire limb

• Peaks at 60-90 minutes and lasts up to 12 hours• Mild subsequent pain may last up to weeks

• Edema, erythema, tissue necrosis• Systemic symptoms

– Hypotension, pyrexia, chills, nausea, muscle twitching, dyspnea, convulsions, dizziness, diaphoresis, and anaphylaxis

Signs

• Single or multiple puncture wounds– Surrounding ring of blue-cyanotic tissue– Subsequent edema, erythema, and warmth

may involved entire limb– Vesicle formation (often in hands) may

progress to rapid tissue sloughing, cellulitis, and surrounding hyperesthesia.

Prehospital Care

• Gentle removal of visible spines

• Direct pressure to control bleeding

• Administration of analgesia

• Immerse wound in hot water (<114F/45C)

• Transport for definitive medical evaluation

Hospital Care

• Tetanus prophylaxis

• Removal of retained spines

• Resusitation with IV fluids

• IV analgesia

• Antibiotic prophylaxis

• Antivenom available, but rarely indicated

Prevention

• Avoidance

• If not avoidance, use proper precautions:– Kevlar gloves– Shears to trim spines– Knife to remove fish from spear– Properly lined catch bag

Quiz!

• An open water diver comes back to the boat complaining of being attacked by a “frilly” striped fish. As you examine the wound, you notice a single puncture wound on the dorsum of his hand with surrounding erythema. He is complaining of substantial pain.

• What do you do next?

What did we learn today?

Summary

• Lionfish stings are increasing due to increased interaction with people in the Atlantic and Carribean oceans

• Wounds appears as

• Field treatment should include immediate removal of spines, analgesia, and immersion in hot water

Summary

• Best prevention is avoidance. However, those wishing to get close should utilize proper equipment (kevlar gloves, knifes, and appropriate catch bag).

• Lionfish can be tasty!

Continuing Education

• Divers Alert Network– www.DAN.org

• Undersea and Hyperbaric Medicine Society– http://membership.uhms.org

• Annals of Emergency Medicine• Emedicine/Medscape

– http://emedicine.medscape.com/article/770764-overview

Additional Information

Lionfish Cookbook

Any Questions ?