Stingrays are found throughout the oceans of the world. Stingrays are not typically aggressive, and the majority of envenomations are defensive in nature. Injuries typically involve a lower extremity if the animal is stepped on or an upper extremity if the animal is handled. Fatal injuries have been reported from chest trauma, which may result in perforation of the myocardium. Stingray envenomation occurs when a reflexive and forceful forward thrust of the caudal spine or spines of the animal impacts the victim, producing a puncture wound or laceration. The force of injection causes the integumentary sheath covering the spine to be driven into the wound, fragmenting and potentially releasing venom, mucus, pieces of the sheath, and spine fragments deep within the wound. Envenomation typically produces immediate and intense pain, edema, and bleeding. The initially dusky or cyanotic wound may progress to erythema, with rapid fat and muscle hemorrhage. Systemic symptoms may include nausea, vomiting, diarrhea, diaphoresis, muscle cramps, fasciculations, weakness, headache, vertigo, paralysis, seizures, hypotension, and syncope.
Management and Disposition
The wound should be irrigated immediately and primary exploration accomplished to remove any visible debris. Pain relief should be initiated early. Opiates may be needed. Stingray venom is made up of heat-labile polypeptides that may be inactivated by immersion in hot water (43°C-46°C [110°F-115°F]) for 30 to 90 minutes. After soaking, wounds should be formally explored, debrided, and dressed for delayed primary closure or primary closure with drainage. Surgical consultation may be warranted in certain injury locations. Imaging should be obtained after debridement to further examine for retained foreign bodies. Broad-spectrum antibiotics covering marine organisms are recommended. Patients can usually be discharged home after a 3- to 4-hour observation period if no systemic symptoms occur. Tetanus prophylaxis should be given if indicated.
Stingrays. (A) Spotted eagle stingray. This graceful stingray was photographed in waters off the coast of Bonaire. Note the three venomous spines at the base of the tail. (Photo contributor: Lynne Bentsen, RN.) (B) Blue spotted stingray. This stingray was photographed in waters off Indonesia. Stingrays often dwell on the ocean floor and may burrow into the sand, leading to envenomation by accidentally stepping on the animal. (Photo contributor: Ian D. Jones, MD.) (C) Southern stingray. This stingray was photographed in the Caribbean. The coloring of the stingray tends to blend with the ocean floor, leading to injury from inadvertent stepping on the stingray. (Photo contributor: Kevin J. Knoop, MD, MS.)
Buried Stingray. Stingrays like to burrow into the sand on the ocean floor, making them very difficult to see and easy to inadvertently step on. (Photo contributor: Keven Reed, OD.)