Page 447 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

414 SECTION | V Metals and Micronutrients

VetBooks.ir damage is irreversible. A blind animal usually does not Supportive therapy may be of even greater value, particu-
Include specific therapy with supportive therapy.
regain sight, but appetite and weight gain will continue if
larly when cardiovascular collapse is imminent, and
the offending arsenic containing food is removed. The
more prolonged the exposure or slow the onset of toxicity, should involve IV fluids to restore blood volume and cor-
the less likely there will be of recovery. rect dehydration. Amino acids and B-complex vitamins
Inorganic arsenicals can be treated. In small animals, should also be included. Kidney and liver function should
if no clinical sigs are evident in a recent exposure, the be monitored during treatment.
animal should have its stomach emptied with warm water
or a 1% solution of sodium bicarbonate solution for gas-
tric lavage. Emetics and strong cathartics and parasympa- CONCLUDING REMARKS AND FUTURE
thomimetic drugs are not recommended as they may DIRECTIONS
cause rupture of the walls of a weakened GI system
(Neiger, 2001). Emesis, cathartics, and charcoal have Determining the diagnosis and initiating treatment early
been used when very early in the process and when there will determine the prognosis. Acutely poisoned animals
are no clinical signs, but are used with caution if at all. have a poor prognosis without early intervention.
However, in arsenic intoxication, the efficacy of charcoal Understanding the differentials is important to institute
is undetermined. Following gastric emptying, provide GI the appropriate treatment for the appropriate condition.
protectants, such as kaolin-pectin. If charcoal has been Arsenic produces signs of severe gastroenteritis, similar
used, then protectants should follow approximately 1 2h to those of pancreatitis, viral or bacterial gastroenteritis,
later in small animals. Fluid therapy is appropriate. If irritating plants, caustic agents, and zinc phosphide poi-
the patient is showing clinical signs, then aggressive fluid soning. Likewise, other heavy metals will produce similar
therapy and if needed, a blood transfusion should be clinical signs. However, poisoning with phenylarsonics,
instituted. In cases with clinical signs, British antilewisite used most frequently in feed additives, has a high morbid-
(BAL, dimercaprol, or 2,3-dimercaptopropanol), at ity rate but is associated with a low mortality rate.
2.5 5 mg/kg, IM as a 10% solution in oil is administered Recovery generally requires 2 4 weeks.
every 4 h for 2 days, then every 8 h for the third day and
only bid for the next 10 days or until recovery (Neiger,
2001). Recall IM solutions with oil can be painful. REFERENCES
In large animals, the efficacy of BAL alone is ques-
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Arsenic Toxicity, Case Studies in Environmental Medicine. US
(50 mg/kg, IM, tid, as a 20% solution) is usually com-
Department of Health and Human Services, Washington, DC.
bined with BAL (3 mg/kg, IM as a 10% solution in oil,
Alamolhodaei, N.S., Shirani, K., Karimi, G., 2015. Arsenic cardiotoxi-
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city: an overview. Env. Toxicol. Pharmacol. 40, 1005 1014.
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