Medicine for the Outdoors
Dr. Paul Auerbach is the world's leading outdoor health expert. His blog offers tips on outdoor safety and advice on how to handle wilderness emergencies.See all posts »
A Jellyfish Tale
In May, I enjoyed a few days' diving in the Baja at La Paz, Mexico. At that time of year, the water is relatively cool and the visibility isn't perfect, but there is still much to see underwater as the nutrients arrive in the currents prior to the return of the big animals, such as hammerhead sharks and whale sharks. The dive operation at the Cantamar Resort was superb, so we were treated to swift and smooth boat rides to the dive sites, excellent dive guides, and wonderful lunches.
The surface of the water was generally flat, and our entries into the water were relatively easy, because there was little current and our group of divers worked well together. We played with sea lions underwater and saw countless pufferfishes, scorpionfishes, multi-colored moray eels, magnificent nudibranchs, bright starfish, barracuda, and stingrays, including a small manta and the bullseye electric ray Diplobatis ommata. As is my habit, I urged everyone to be careful and to avoid touching animals, sharp corals, or anything with which they were unfamiliar.
The sun was very hot, so it was important to use sunscreen and lip balm. I shared my supply of Safe Sea with everyone. This is a combination sunscreen-jellyfish sting inhibitor product that has been tested and found effective against many species of stinging creatures. When applied properly, it stays on the skin for 45 minutes to one hour underwater and is formulated to diminish or prevent stings from jellyfish or other similar creatures equipped with microscopic stinging cells. I never (well, almost never, as you will soon learn...) enter the ocean without covering my exposed skin with this product, because why not take every advantage to not be stung? Jellyfishes and other marine stingers are often effectively camouflaged, way too small to be noticed, or are slightly submerged under the surface, which renders them virtually invisible to the naked eye.
On one particular dive, we were anchored close to a lighthouse upon a rock outcropping that served as a resting place for about 20 sea lions. The water surface showed a slight chop due to the wind, so it was difficult to visualize anything translucent on the surface. I donned my full wet suit, buoyancy compensator, and mask, but did not "smear up" with Safe Sea for this water entry, so my hands, neck, and face were exposed. and jumped feet first off the boat into the water. Someone then handed me my underwater camera, and I kicked gently to the anchor line to meet up with the other divers. In a flash, I experienced incredibly intense burning pain over both of my hands and wrists. The top of my left hand was on fire, while the underside of my right wrist hurt as if it had suddenly been lanced with 1000 needles. I stuck my facemask in the water and saw the purple "sails" of two small Portuguese man-of-war "jellyfish" (colonial siphonophores actually, but that's not critical to the discussion), with long trailing dark tentacles that terminated in their attachment to my body. The tentacles stuck to my skin like the webs emitted by Spiderman, so I shook my hands and forearms as hard as I could to pull them loose, to no avail.
I held my camera in my left hand, and while shaking it, the muscles in my hand and wrist went into a brief intense spasm from the sting, so I dropped the camera, which spiraled down into the depths below me. Fortunately, it came to rest in clear view 60 feet below me. Another diver thoughtfully dove down and retrieved it. Meanwhile, the friend of my son, who was diving with us, caught a tentacle across the throat, and was stunned and frightened. He exited the water and went back up on the boat to sit out the dive. I didn't see or hear him become injured, so I had no idea that he had been stung or was now suffering back on deck.
I pulled and rubbed the tentacles off my hands while I was in the ocean, waited a few moments, decided that I could tolerate the pain, and continued my dive. While I was underwater, my son's friend attempted to treat his sting by rubbing it with an ice cube, which is not the correct thing to do. When I ended my dive and returned to the boat, I learned of his sting, and treated him with an effective therapy - application of a mixture of rubbing alcohol and vinegar to the skin, which immediately ended the stinging pain.
Shame on me for not using Safe Sea before I entered the water. Had I followed my own advice, I would either have not been stung or had a much less severe reaction to the man-of-war. I've warned so many thousands of people of the hazards of getting stung that you would think I'd be a bit smarter. I can assure you that from this point forward, I won't be diving without taking proper precautions. Four days after the original sting, the skin reaction resembled a bad poison oak rash, with red, raised, and itchy bumps that perfectly define the attachment of the tentacles to my skin. It required a full four weeks for the rash to resolve.
I hope that none of you ever has the need for the following advice, but just in case you are in the ocean and are stung by a Portuguese man-of-war, jellyfish, or other similar stinging creature, here is what you should do:
1. Exit the water if possible.
2. Immediately rinse the wound with seawater, not with freshwater. Do not rub the wound with a towel or clothing to remove adherent tentacles. Nonforceful freshwater rinsing or a rubbing variety of abrasion is felt to stimulate any microscopic stinging cells that have not already fired. Surf life savers (lifeguards) in the United States and Hawaii have reported that a freshwater hot shower applied with a forceful stream may decrease the pain of an sting.
3. Remove any visible tentacles with forceps or a well gloved hand. In an emergency, the palm of the hand is relatively protected, but take care not to become stung.
4. Commercial (chemical) cold or ice packs applied over a thin dry cloth or plastic bag have been shown to be effective when applied to mild or moderate stings. Whether the melt water from ice applied directly to the skin can stimulate the discharge of stinging cells has not been determined.
5. Acetic acid 5% (vinegar) is the treatment of choice to inactivate most jellyfish toxins. The vinegar should be applied continuously for at least 30 minutes or until the pain is relieved. This may be done by soaking a napkin or cloth and placing it on the affected skin.
6. Different species respond better or worse to different topical decontaminants. There are substances that may be more specific and therefore more effective. Depending on the species, these include isopropyl (rubbing) alcohol (40% to 70%), dilute ammonium hydroxide, sodium bicarbonate (baking soda), lemon or lime juice, olive oil, sugar, urine, and papain (papaya latex [juice] or unseasoned meat tenderizer powdered or in solution).
7. Perfume, aftershave lotion, and high proof liquor are not particularly useful and may be detrimental. Other substances mentioned to be effective at one time or another, but which are to be condemned on the basis of toxicity, are organic solvents such as formalin, ether, and gasoline.
Immersing the area in hot water has generally not been recommended, on the premise that the fresh water solution causes stinging cells to discharge. However, one study compared hot (40 to 41 degrees Centigrade [104 to 105.8 degrees Fahrenheit]) water immersion to papain meat tenderizer or vinegar for treatment of a single-tentacle Carybdea alata (Hawaiian box) jellyfish sting to the forearm, and found the hot water immersion to be the most beneficial.
Once the wound has been soaked with a decontaminant (e.g., vinegar), remaining (and often “invisible”) stinging cells must be removed. The easiest way to do this is to apply shaving cream or a paste of baking soda, flour, or talc and to shave the area with a razor or similar tool. If sophisticated facilities are not available, the stinging cells should be removed by making a sand or mud paste with seawater and using this to help scrape the victim’s skin with a sharp edged shell or piece of wood. The rescuer must take care not to become stung; bare hands must be rinsed frequently.
Tags: Portuguese man-of-war, jellyfish, marine sting, medical, physician, health, wilderness medicine, outdoor medicine, healthline
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