I love talking with veterinarians around the country. Sometimes, these conversations focus on working through errors in cattle management, such as vaccination or treatment-protocol violations.
As hard as we try to plan our work and work our plan, sometimes things go wrong. Therefore, part of our plan should be how to identify errors and control the negative impacts on your operation.
Unfortunately, drug-overdosing is not an uncommon occurrence.
When more than the proper dose is administered, the first consideration is the safety of the animal. The extent of the overdose should be determined and recorded. Then, consult your veterinarian and the drug label.
Many labels contain detailed information on toxicity, including the doses tested in toxicity trials and the likely adverse effects you will observe. Have the label handy when you talk to your veterinarian as he may not have immediate access to the label when you call.
Some drugs may require treatment or supportive therapy for the overdose. Many facilities have epinephrine on hand for treatment of anaphylactic shock, but epinephrine is inappropriate for treatment of reactions to some drugs that may be on your operation.
If your veterinarian has provided epinephrine for use in emergencies, make sure everyone understands where it should and shouldn't be used. Readily available written instructions are the best.
Just like all other drugs, epinephrine has an expiration date, after which it should be discarded and replaced.
Second, ensure animals involved can be positively identified. This means some form of individual ID that will stay with the animal until any extended slaughter withdrawal issues are resolved. Individually numbered ear tags are appropriate, while chalk marks, bobbed tails, or characteristic markings of the animal are not sufficient.
Third, assign an extended slaughter withdrawal time to the animal. Veterinarians have access to a service to assist them in identifying the proper extended withdrawal time.
Failure to individually identify the animal makes it necessary to apply any extended withdrawal time to the entire group of animals. Document that this withdrawal time was determined and applied to the animals involved.
Fourth, figure out why the error happened. Do you have written treatment guidelines with detailed instructions? Are there sit-down sessions with your veterinarian and everyone who will be treating cattle in order to establish treatment procedures?
Changing administration techniques can have serious consequences. For example, one common antimicrobial is completely safe for cattle when administered subcutaneously according to label directions, but the same dose is likely fatal if given intravenously.
Errors like this can happen due to misidentification of the drug being administered. Drugs should always be kept in their original containers, and the drug should be consciously identified each time before it's pulled into a syringe.
The response steps and need for planning for alterations in administration technique are the same as for overdosing. Changing the route of administration may drastically alter the slaughter withdrawal time.
Altering the route of administration constitutes extra-label use, and should only be done after careful planning within a veterinary-client-patient relationship.
Broken needles in an animal require immediate attention. Veterinarians who have addressed broken needles with ultrasound location and removal tell me needle shafts can migrate several inches in an hour, either going deeper or moving laterally under the skin or in superficial tissues.
Needle removal is a surgical procedure that's most successful if performed immediately. If the needle can't be identified and removed, the animal should not enter the food chain.
A broken needle is the result of inappropriate needle selection and/or use, likely combined with inappropriate restraint. Injecting cattle in an alley and pasture treatment are two of the most likely situations for broken needles.
A bent needle is a broken needle and should be discarded immediately.
When administering drugs in cattle, we have enormous responsibilities to both the cattle and the eventual consumer of our product. Have a plan in place to prevent and respond to drug-administration errors so the safety of the wholesome product we produce is maintained.
Mike Apley, DVM, PhD, is an associate professor in clinical sciences at Kansas State University in Manhattan.