Stingray Injuries FINDLAY E. RUSSELL, M.D. inflicted by stingrays are com¬ the integumentary sheath surrounding the INJURIESmon in several areas of the coastal waters spine is ruptured and the venom escapes into of North America (1-4). Approximately 750 the victim's tissues. In withdrawing the spine, people a year along our coasts are stung by the integumentary sheath may be torn free and these elasmobranchs. The largest number of remain in the wound. stings are reported from southern California, Unlike the injuries inflicted by many venom¬ the Gulf of California, the Gulf of Mexico, and ous animals, wounds produced by the stingray the south Atlantic coast (5). may be large and severely lacerated, requiring Of 1,097 stingray injuries reported over a 5- extensive debridement and surgical closure. A year period in the United States (5, tf), 232 sting no wider than 5 mm. may produce a were seen by a physician at some time during wound 3.5 cm. long (#), and larger stings may the course of the recovery of the victim. Sixty- produce wounds 7 inches long (7). Occasion¬ two patients were hospitalized; the majority of ally, the sting itself may be broken off in the these required surgical closure of their wounds wound. or treatment for secondary infection, or both. The sting, or caudal spine, is a bilaterally ser¬ At least 10 of the 62 victims were hospitalized rated dentinal structure located on the dorsal for treatment for overexuberant first aid care. surface of the animal's tail. The sharp serra¬ Only eight patients were hospitalized for the tions are curved cephalically and as such are treatment of the systemic effects produced by responsible for the lacerating effects as the sting the venom. There were two fatalities. is withdrawn from the victim's flesh. The loca¬ Considerable care should be exercised when tion, size, and number of stings vary with the wading in shallow waters known to be inhabited species, habitat, and age of the fish. The round by stingrays. Stingray injuries usually occur stingray, now designated as Urolophus halleri, when the unwary victim treads upon the fish which is implicated in the majority of injuries while wading in the ocean surf or mud flats along the southern California coast, has one or of a bay, slough, or river. The fish often buries more stings of 1.6 to 5.9 cm. long (8). The itself in the sandy or muddy bottom and may giant stingray of Australia, Bathytoshia, may remain motionless until stepped upon. The possess a caudal spine of 42.0 cm. long (9). pressure of the foot on the dorsum of the fish The greatest portion of venom is contained provokes him to thrust his tail upward and within the two ventrolateral grooves of the forward, driving his sting into the foot or leg sting. In the untraumatized state, the sting is of the victim. As the sting enters the flesh, incased in an integumentary sheath. The ana¬ tomic of the sheath and Dr. Russell is director of the laboratory of neuro¬ relationships sting logical research of the College of Medical Evange¬ have been described elsewhere {10-12). lists and Los Angeles County Hospital. Basic data Chemical and in the report were obtained from studies supported Zootoxicological Properties by the Office of Naval Research, Dazian Foundation The toxic fractions of the venom are soluble for Medical Research, and the Public Health Service. proteins of average molecular weight. They Vol. 74, No. 10, October 1959 855 are extremely labile and rapidly inactivated by the venom show few gross changes. However, heating. Ten amino acids have been identified pulmonary edema, engorgement of the liver in the venom. The total nitrogen, carbohydrate, sinusoids, and vascular congestion with tubular and protein for 100 mg. of the venom has been epithelial necrosis in the loop of Henle are calculated as 3.1 mg., 3.3 mg., and 24.9 mg. seen (IS). respectively. The intravenous LD50 of the lyophilized venom is estimated at 28.0 mg./kg. Diagnosis of body weight (IS). Persons stung by stingrays report having In venom addition to the local effects (12), the received a sharp, painful stab, usually in the produces changes in the cardiovascular, respira¬ foot or leg, while swimming or wading in an tory, nervous, and urinary systems (5, 1^ IS). area where these animals are present. The Low of pain concentrations the toxin give rise to is usually described as intense or excruciating; simple, transient peripheral vasodilatation or it increases in severity during the first 90 min¬ vasoconstriction. The most consistent change utes following the stinging if treatment is not in the eiectrocardiographic pattern of cats when instituted. The pain is out of proportion to small amounts of the venom are injected is that which might be produced by a nonvenom¬ bradycardia with an increase in the PR interval, ous fish or by stepping upon a broken bottle or giving a first degree atrioventricular block with bivalve. "Stingings" by broken bottles, are a but slight change in the blood pressure. Re¬ common occurrence along certain of our coasts, versal of the small dose effect occurs within 30 according to the lifeguard services. seconds following the end of the injection Examination reveals either a puncture or (14,16). a lacerating wound, usually the latter, jagged, Larger amounts produce constriction of the bleeding freely, and often contaminated with arteries and veins as well as the arterioles, and parts of the stingray's integumentary sheath. second or third degree atrioventricular block. The edges of the wound may be discolored, The second degree block is usually followed by though the discoloration is not usually marked sinus arrest. In addition to the PR interval immediately following the injury. However, change, ST, T wave changes indicative of within 2 hours the discoloration may extend ischemia and, in some animals, true muscle in¬ several centimeters from the wound. Subse¬ jury are seen (15,16). Concomitant with these quent necrosis of this area is not uncommon in changes is a fall in systemic arterial pressure. untreated cases. It is apparent that the venom affects the normal Edema is a constant finding following sting¬ pacemaker of the heart. Most of the cardio¬ ings by these animals. The edema is not as vascular changes revert to normal within 24 severe as one sees following a rattlesnake bite, hours (5). but it may persist for several weeks in the un¬ Lethal amounts of the venom cause marked treated case. Syncope, weakness, nausea, vasoconstriction and cardiac standstill of vary¬ nervousness, and sweating are common com¬ ing durations. All degrees of atrioventricular plaints. Vomiting, diarrhea, tremors, general- block as well as defects in intraventricular con¬ duction occur, and if death is not immediate, the rhythm of the normal pacemaker is re¬ placed by one elaborated outside the sino-atrial node. The blood pressure falls rapidly, and the animal dies in complete cardiovascular collapse (5,11},1S). Concomitant with these changes are alterations in the respiratory and central nervous systems (SjlS). The venom has no effect on neuromuscular conduction (17). Postmortem examination of animals which have survived for 4 days following a lethal dose of The round stingray Urolophus halleri 856 Public Health Reports An Early Case History An early stingray victim was Captain John But it chansed our Captaine taking a fish Smith. Walter Russell, "Gentleman, doctor from his sword (not knowing her condition) of physicke," who accompanied Smith as he being much of the fashion of a Thornback. explored Chesapeake Bay in June 1608, de¬ but a long tayle like a ryding rodde, whereon scribed the encounter in chapter 5, "The Acci¬ the middest is a most poysoned sting, of two dents that hapned in the Discovery of the or three inches long, bearded like a saw on Bay of Chisapeack" of The Third Booke of each side, which she strucke into the wrest of The Proceedings and Accidents of the English his arme neere an inch and a halfe: no bloud Colony in Virginia. nor wound was seene, but a little blew spot, but the torment was instantly so extreme, that . Having finished this discovery (though in foure houres had so swolen his hand, arme our victuall was neere spent) he intended to and shoulder, we all with much sorrow con¬ see his imprisonment-acquaintances upon the cluded his and his in river of called funerall, prepared grave Rapahanock, by many Toppa- an Island by, as himselfe directed: yet it but our bote reason of the hanock, by ebbe, pleased God by a precious oyle Doctor Russell chansing to grownd upon a many shoules at the first applyed to it when he sounded it lying in the entrances, we spyed many fishes with probe, (ere night) his tormenting paine lurking in the reedes: our Captaine sporting was so well asswaged that he eate of the fish himselfe by nayling them to the grownd with to his supper, which gave no lesse joy and his sword, set us all a fishing in that manner: content to us then ease to himselfe. For which thus we tooke more in owne houre then we we called the island Stingray Isle after the could eate in a day. name of the fish. ized cramps, inguinal or axillary pain, and may apply a constriction band directly above respiratory distress are less frequently re¬ the wound site. The extremity should then be ported. Arrhythmias, paresthesias, and con¬ submerged in hot water at as high a tempera¬ vulsions may occur. True paralysis is ex¬ ture as the patient can tolerate without injury tremely rare, if it occurs at all.