Dr. Paul Auerbach, a leading expert on the clinical management of hazardous marine life encounters, answers questions about treating coral scrapes and sea urchin spine punctures.
I was snorkeling in Bonaire over a patch of elkhorn coral and dove down to get a closer look at a sea fan. A boat zoomed by and I got shoved by the swell. My knee scraped against a horn of coral. I was surprised that it stung. Rubbing it didn't help. When I got back to the hotel, one of the cooks told me to rub it with meat tenderizer, but we didn't have any. Now it's been two weeks and the skin on my knee doesn't seem to be healing. What should I do?
Coral scrapes are among the most common injuries resulting from marine life encounters. The surface of coral is covered by soft living material, which is easily torn from the rigid (abrasive) structure underneath, and thus deposited into the scrape or cut. This greatly prolongs the wound-healing process by causing inflammation and, occasionally, initiating an infection. Cuts and scrapes from sharp-edged coral and barnacles tend to fester and may take weeks or even months to heal.
Scrub the cut vigorously with soap and water, and then flush the wound with large amounts of water.
Flush the wound with a half-strength solution of hydrogen peroxide in water. Rinse again with water.
Apply a thin layer of bacitracin, mupirocin (Bactroban), or other similar antiseptic ointment, and cover the wound with a dry, sterile, and non-adherent dressing. If no ointment or dressing is available, the wound can be left open. Thereafter, it should be cleaned and re-dressed twice a day.
If the wound develops a pus-laden crust, you may use "wet-to-dry" dressing changes to remove the upper non-healing layer in order to expose healthy, healing tissue. This is done by putting a dry sterile gauze pad over the wound (without any underlying ointment), soaking the gauze pad with saline or a dilute antiseptic solution (such as 1- to 5-percent povidone-iodine in disinfected water), allowing the liquid to dry, and then ripping the bandage off the wound. The dead and dying tissue adheres to the gauze and is lifted free. This method may be painful for the patient. The pink (hopefully), slightly bleeding tissue underneath should be healthy and healing. Dressings are changed once or twice a day. Wet-to-dry dressings are used for a few days, until they become non-adherent or the tissue appears infection-free. At that point, switch back to #3 above.
If the wound shows any sign of infection (extreme redness, pus, swollen lymph glands), the injured person (particularly one with impairment of his or her immune system) should be started by a qualified health professional on an antibiotic, taking into consideration the possibility of a Vibrio infection. Vibrio bacteria are found more often in the marine environment than on land, and can rapidly cause an overwhelming illness and even death in a human with an impaired immune system (e.g., someone with AIDS, diabetes or chronic liver disease). A common oral antibiotic that is usually effective against Vibriospecies is ciprofloxacin (Cipro).
Coral poisoning occurs if coral abrasions or cuts are extensive or are from a particularly toxic species. Symptoms include a wound that heals poorly or continues to drain pus or cloudy fluid, swelling around the cut, swollen lymph glands, fever, chills and fatigue. If these symptoms are present, the injured person should see a physician, who may elect to treat the person with an antibiotic and/or corticosteroid medication.
Sea Urchin Spines
I was chasing a big marble ray underwater near Cocos Island (I wanted to photograph it) and wasn't paying attention to my buoyancy. I brushed by a rock wall and suddenly felt severe burning in my arm and elbow. There were 15 black sea urchin spines sticking out of my forearm. The spines had gone right through my diveskin. I remembered hearing that it helps to urinate on a sea urchin sting, so I tried it, but it didn't help. Most of the black spots on my arm have disappeared, but I still can see two, and my wrist is starting to swell. What should I do?
Some sea urchins are covered with sharp venom-filled spines that can easily penetrate and break off into the skin. Others (found in the South Pacific) may have small pincer-like appendages that grasp their victims and inoculate them with venom from a sac within each pincer. Sea urchin punctures or stings are painful wounds, most often of the hands or feet. If a person receives many wounds simultaneously, the reaction may be so severe as to cause extreme muscle spasm, difficulty in breathing, weakness and collapse.
Immerse the wound in non-scalding hot water to tolerance (110 to 113° F / 43.3 to 45° C). This frequently provides pain relief. Other field remedies, such as application of vinegar or urine, are less likely to diminish the pain. If necessary, administer pain medication appropriate to control the pain.
Carefully remove any readily visible spines. Do not dig around in the skin to try to fish them out - this risks crushing the spines and making them more difficult to remove. Do not intentionally crush the spines. Purple or black markings in the skin immediately after a sea urchin encounter do not necessarily indicate the presence of a retained spine fragment. The discoloration more likely is dye leached from the surface of a spine, commonly from a black urchin (Diadema species). The dye will be absorbed over 24 to 48 hours, and the discoloration will disappear. If there are still black markings after 48 to 72 hours, then a spine fragment is likely present.
If the sting is caused by a species with pincer organs, use hot water immersion, then apply shaving cream or a soap paste and shave the area.
Seek the care of a physician if spines are retained in the hand or foot, or near a joint. They may need to be removed surgically, to minimize infection, inflammation and damage to nerves or important blood vessels.
If the wound shows any sign of infection (extreme redness, pus, swollen regional lymph glands) or if a spine has penetrated deeply into a joint, the injured person (particularly one with impairment of his or her immune system) should be started by a qualified health professional on an antibiotic, taking into consideration the possibility of a Vibrio infection.
If a spine puncture in the palm of the hand results in a persistent swollen finger(s) without any sign of infection (fever, redness, swollen lymph glands in the elbow or armpit), then it may become necessary to treat the injured person with a seven- to 14-day course of a non-steroidal anti-inflammatory drug (e.g., ibuprofen) or, in a more severe case, with oral prednisone, a corticosteroid medication.