In memory of Mr. Irwin's untimely death, I would like to do a brief study of the creature that accidentally killed him- the Stingray, which often have venomous tails.
The stingray are bottom-dwelling cartilaginous fish that have a flattened body, 1 or more stout spines on the tail, gill slits on the lower surface of the head, teeth modified into 2 large crushing plates, and no dorsal fin. They are not aggressive toward humans; however, injuries from these animals are very common, and can occasionally lead to death.
Each tail spine has 2 ventrolateral venom-containing grooves that are encased in an integumentary sheath and this apparatus acts as its mian form of self defense. These spine grooves have the poison glands. If an unwary wader steps on this ray, they could be stung causing excruciating pain. There are only 17 known cases in the literature of deaths associated with these spines prior to Mr. Erwin's death.
A closeup view of the tail spine.
EMERGENCY TREATMENT:
- If a patient has demonstrated any sign of systemic effect, it should be addressed quickly.
- No specific antidote is available, and supportive care is recommended, including use of analgesics.
- An easy and important initial treatment that can be started (sometimes at the scene of the injury) is immersion of the injured extremity in hot water (preferably 110-115°F). The water should be as hot as the patient can tolerate but should not cause burns. The water should be exchanged for more hot water as it cools, for an immersion duration of 30-90 minutes.
- Very little has been written about the toxin left in wounds after a stingray injury. It is known that the stingray toxin is a protein and is very sensitive to heat. The patient should obtain very rapid symptomatic improvement with heat as the poison denatures and becomes neutralized. Some thought exists that the protein does not truly denature but that some sort of gateway effect occurs on the nerve conduction. Whatever the truth is regarding how heat works, it is a rapid, effective treatment to reduce pain almost instantaneously.
- In addition, some practitioners also infiltrate the wound with a local anesthetic, such as lidocaine (lignocaine) or the longer-acting bupivacaine. Occasionally, oral or parenteral narcotics may also be given.
- After the toxin has been deactivated by the hot water, attention to local wound care should begin because it is not uncommon for part of the stinging apparatus to break off in the wound.
- Obtain a plain radiographic image of the injured area to look for retained barbs or other foreign material. Explore the wound thoroughly and irrigate it. Perform any necessary debridement.
- Remove any foreign body from the wounds, including the spine and sheath from the stingray stinger, as well as dirt or sand.
- As with other potentially contaminated wounds, consider allowing the wound to heal without closure. Because most of the wounds are small, this usually is not an issue. If the wound is very large or gaping, consider loose primary closure.
- Address the patient's tetanus immunization status and administer a booster as needed.
It's relative, the Manta Ray (Manta birostris) is more closely related to sharks. Like the shark their skeleton is made of cartilage. 
On average they are about 20 feet wide and weigh up to 3000 pounds. They are the largest of the rays. Unlike the stingray, they are harmless to divers.
Bibliography:
- Website 1
- Website 2 (This one has the treatment suggestions mentioned above.)
RIP Steve!
Posted
Sep 06 2006, 02:16 AM
by
alborg