Ethylene glycol exposures managed by the ASPCA National Animal Poison Control Center from July 1995 to December 1997.

Five-hundred and ten cases of ethylene glycol (EG) exposures in animals were compiled by the ASPCA National Animal Poison Control Center from July 1995 through December 1997. Case distribution was analyzed by species, sex, age, weight, seasonality, treatment intervention and final outcome. Dogs and cats were most commonly involved (98.0%). The sex distribution was approximately equal. Adult animals accounted for the majority of cases. Exposures were commonly (57.0%) from container spill, engine flush, or engine leak and were in or around the home (66.0%). Cases were reported throughout the year with slight increase during March-May. Among cases with a known final outcome, 59.0% did not show clinical signs and death/euthanasia, major and minor illness was reported in 28.0%, 5.0% and 8.0%. In view of the widespread use and potential toxicity of EG, the low number of EG exposures reported (510) among the total number of hazardous exposures (97,383) to all substances for the same period was remarkable. The EG exposures resulting in animal death/euthanasia were lower than previously published.

The potential utility of animal poisoning data to identify human exposure to environmental toxins.

The database of the National Animal Poison Control Center (NAPCC) was evaluated as a source for animal poison data indicating human health hazards in indoor and outdoor environments. From 14,150 calls in the 1985 database, 259 cases were identified with histories suggesting human exposure. A subgroup of 25 cases with known human exposure was found. Dogs were the most common sentinel animal, but bird cases represented the highest proportional selection from the total 1985 call list. Indoor exposures represented 43.2% of cases; the most common toxicants were insecticides, lead and toxic fumes. Exposures associated with lawns were mainly due to insecticides and herbicides and constituted 25.5% of cases. Other outdoor exposures composed the remaining 31.7% of cases, with insecticides, herbicides and unidentified toxins the leading categories. Many of the specific agents identified, such as organophosphate insecticides, lead, gas and fume toxins, and phenoxy herbicides are also risk factors in human diseases. This study indicates that databases such as NAPCC could serve as sources of sentinel animal intoxications for followup studies to evaluate known and potential human health hazards.

Toxicology of selected pesticides, drugs, and chemicals. Illicit and abused drugs.

Toxicoses involving exposures to illicit and abused substances are an occasional problem in veterinary patients. The difficulties of clinical diagnosis and the importance of obtaining a good history are emphasized. A discussion of some of the more common poisonings is presented, including available sources, clinical signs, toxicity, metabolism, mechanism of action, and the treatment for each agent.

Fenvalerate/N,N-diethyl-m-toluamide (Deet) toxicosis in two cats.

Toxicosis attributable to fenvalerate and N,N-diethyl-m-toluamide (Deet) exposure was suspected in 2 cats. Clinical signs of toxicosis developed within 4 to 6 hours of dermal application of the pesticide. Clinical signs of toxicosis seen in both cats included hypersalivation, ataxia, and depression. In addition, seizures were seen in 1 cat. Both cats died. Analysis of skin, kidney/urine, liver, and brain tissues confirmed the presence of fenvalerate and Deet. The pyrethroid fenvalerate and the insect repellent Deet are used for the control of fleas and ticks on cats. Suspected fenvalerate/Deet toxicosis in cats is associated with tremors, hypersalivation, ataxia, vomiting, depression, and seizures.

Therapeutic dosing of pralidoxime chloride.

Pralidoxime chloride is a useful agent in the treatment of organophosphate poisoning. Poisindex, a widely used poisoning treatment resource, recommends dosing pralidoxime chloride as an intermittent iv infusion every 8-12 hours, whereas other authors have used continuous iv infusion with good results. Available animal data suggest that a serum concentration of 4 micrograms/ml may be a minimal level to protect against the toxic effects of organophosphates. Pharmacokinetic simulations, based on parameters obtained from healthy nonpoisoned subjects, show that pralidoxime levels fall rapidly to less than 4 micrograms/ml within 1.5-2 hours after a 1-g iv bolus. Continuous iv infusion (0.5 g/h) maintains pralidoxime levels greater than 4 micrograms/ml throughout the length of infusion. We conclude that continuous iv infusion of pralidoxime chloride may be the preferred method of administration in patients with acute organophosphate poisoning. Clinical trials will be necessary to document the effectiveness of this regimen.

Evaluation of regional and nonregional poison centers.

The purpose of this study was to determine whether regional poison centers handle a particular poisoning situation better than nonregional centers do. Informed consent was obtained from 15 regional and 15 nonregional poison centers. A case involving salicylate ingestion by a three-year-old child was presented twice (one day call and one night call) to each center. Those answering the phone at the regional centers asked more information-gathering questions than did those at the nonregional centers (P less than 0.01) and were more proficient in their history taking (P less than 0.01). Nonregional centers did not consider the potentially toxic ingestion (220 mg per kilogram of body weight) important enough to treat or were not willing to handle the poisoning in one third of the calls. The nonregional centers recommended manual stimulation to induce emesis in 30 per cent of the calls, whereas none of the regional centers recommended this treatment. Four calls to the nonregional centers resulted in recommendations of inappropriate emetics--e.g., saltwater, raw eggs, or mustard water. The chance of obtaining incorrect recommendations for poisoning treatment from the nonregional centers was determined to be nine times greater than that from the regional centers. Indications of intention to follow up were twice as frequent among regional as among nonregional centers. These data strongly suggest that regional poison centers provide better and more consistent poison information than do nonregional centers.

Repetitive doses of activated charcoal in Dapsone poisoning in a child.

A case of Dapsone poisoning, treated by repetitive dosing with activated charcoal, is reported. This 18-month-old child showed remarkably rapid resolution of his symptoms with this mode of therapy, becoming symptom free in 64 h. This rapid improvement is attributed to interruption by activated charcoal of the enterohepatic circulation of Dapsone. This mode of therapy may be indicated for other compounds having an enterohepatic circulation.

Collaborative clinical pharmacokinetic services.

A program for routine pharmacokinetic interpretation of serum analyses of gentamicin, tobramycin, amikacin, phenytoin, phenobarbital, theophylline, lidocaine, digoxin, quinidine, and procainamide at the Medical University of South Carolina Hospital is described. Results of all analyses of serum for the drugs listed are evaluated by a pharmacist trained in clinical pharmacokinetics. Patient variables relevant to the determination of drug serum concentrations, drug elimination, distribution, and dosage are given appropriate consideration in each evaluation. A summary of the pharmacokinetic interpretation and any necessary modification of drug dosage regimens are then written into the progress notes of the patients' medical records. Approximately 12 patients and 20 drug concentrations are evaluated each day. The average charge for te service is +35. This service, which is reimbursed by third-party carriers, has resulted in improved use of laboratory personnel, equipment, and time and has provided a framework for education and research as well as a mechanism for direct contributions to patient care by the pharmacist.