THE DANGERS OF WIRE INGESTION
It doesn’t happen often, but when a horse inadvertently ingests segments of wire, the consequences can be deadly. A new study from Colorado State University suggests that prompt detection of the problem and aggressive treatment can greatly increase the odds of survival.
The retrospective study was based on the cases of 16 horses---ultimately diagnosed as having ingested wire---that were admitted to the University clinic over an 11-year period. Of those horses, 12 died as a result of the wire.
“Any horse can pick up a wire if it is in the environment,” says Eileen Hackett, DVM, PhD. “One horse in this report was eating meals out of a steel-belted radial tire that had started to unravel, so this should definitely be checked and avoided. This syndrome has also been observed in horses with dental wires that cycle, break and are swallowed. Good management practices are key, but accidents happen.”
The study horses showed signs of colic for an average of five days before being admitted to the clinic. “[Signs of] ingested wire can look identical to other types of colic, though
lethargy and other signs consistent with peritonitis are often associated with penetration of the alimentary tract,” says Hackett. In all but three of the study horses, the wires had perforated the digestive tract, and 10 of those horses subsequently developed abscesses as the body tried to “wall off” and contain the wire.
While ultrasound imaging failed to detect wire segments in most of the horses it was used on, radiographs proved to be largely effective in determining the location of the foreign material. In the seven horses who underwent radiography, a single segment of wire was found in four and multiple pieces of wires were discovered in two. Wire fragments were an incidental finding in two horses who had been admitted for feed or sand impactions. In two of the study horses, wire segments were first spotted during exploratory surgery and in eight horses, the wires were found during a necropsy.
None of the six horses who received medication, without surgery, survived. “A medical approach only might have been instituted for the horse’s general signs if the source was unknown, or in order to treat the signs prior to pursuing surgery that was subsequently not elected in light of presumed poor prognosis,” says Hackett.
Likewise, horses with higher median white blood cell counts, neutrophil counts and plasma total protein concentration were less likely to survive. “We interpreted these signs such that these were horses with more long-standing wire penetration syndromes,” she says.
Four of the eight study horses that underwent surgery survived. But, says Hackett, the case records indicate that the procedures were often complex. “Repair of damaged structures is also important in some cases, so this needs to be assessed at the time of surgery,” says Hackett. “In some instances, resection and removal of damaged intestines might be elected, in addition to rinsing the area with sterile fluids to remove the majority of the contamination.”
Although wire ingestion isn’t a common cause of colic, Hackett says increased awareness may help more horses survive. “We are hoping that this report highlights this and supports that recognition of this phenomenon by the horse’s caregiving team might lead to earlier diagnosis and treatment of this rare disorder, improving overall outcomes.”
Reference: “Clinical features, diagnostic methods, treatments, and outcomes associated with ingested wires in the abdomen of horses: 16 cases (2002–2013),” Journal of the American Veterinary Medical Association, September 2018
“Any horse can pick up wire if it is in the environment,” says Eileen Hackett, DVM, PhD. “One was eating meals out of a steel-belted radial tire that had started to unravel. This syndrome has also been observed in horses with dental wires that cycle, break and are swallowed.”