Keeping cats safe

Rebecca Gamble qualified in 2008 fromAskham Bryan College after working formany years in general practice. Rebeccaenjoys teaching new nursing students sobecame a clinical coach. After working for aVets Now Emergency Clinic she recentlybecame head nurse at Vets4Pets CatterickGarrison, UK. Rebecca finds nursingemergency patients rewarding and isstudying for a certificate in emergency andcritical care.

Rebecca GambleRVN

Case: Molly survives antifreezepoisoning

Ethylene glycol is found in antifreeze products and ishighly toxic to cats, causing acute kidney injury anddeath in many cases. The high mortality may be due todelays in presentation to the vet. In this case a youngcat was witnessed ingesting antifreeze in a garage andwas treated with fluid therapy and the antidote in theform of ethanol (vodka). The cat was monitored closelyfor complications such as hypothermia and volumeoverload and recovered fully because of prompttreatment.

Ethylene glycol is a colourless, odourless,chemical found in many household

products, including antifreeze, de-icingproducts and screenwashes. Cats arenotorious for finding their way under carbonnets looking for warm engines orwandering around in garages where therecould be a spillage of antifreeze. This is whereethylene glycol poisoning becomes a graveconcern. Prognosis is often poor, dependingon the time between ingestion andpresentation at the veterinary clinic. This caseillustrates a case of ethylene glycol toxicitywith a happy outcome. The veterinary team asa whole were vital to the successful outcomeof this case.

HistoryMolly, an 8-month-old female neutereddomestic shorthaired cat, weighing 2.6 kg,had been brought into her daytime veterinaryclinic 1–2 h after having been seen licking apuddle of spilt ethylene glycol from a carengine on the floor of the owner’s garage.

On presentation she was lethargic and hadhindlimb ataxia. She had been placed onintravenous fluid therapy (Hartmann’ssolution) and then started on a continuousrate infusion (CRI) of ethanol (vodka). She

was transferred to my practice forovernight care and ongoingtreatment. After seeking advice fromthe Veterinary Poisons InformationService (VPIS) we increased the

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TipMake sure yourclients are aware ofthe dangers ofethylene glycol —Molly’s owners were andpromptly bringing her to thesurgery meant she could start toreceive the antidote ethanol inthe form of 40% vodka.

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infusion dose using the followingprotocol:

• Make a 5% solution of ethanol byremoving 125 ml of fluid from a 1 litre bag of Hartmann’s andreplacing with 125 ml of 40%vodka. The CRI is run at 5 ml/kg/hso 13 ml/h. The CRI was givenusing a syringe driver to ensureaccuracy of the dose (Figure 1).

Anti-emetics and gastro-protectantswere also administered at regularintervals (ranitidine and maropitant).

Nursing prioritiesNursing priorities included:• Maintenance of the intravenous(IV) catheter including checkingpatency, condition of the insertionsite (ie, checking for redness,pain, etc). The bandage waschecked regularly to ensure ithasn’t slipped or become soiled.

• Management of a recumbentpatient. The infusion of ethanolhad resulted in Molly becomingvery sedated and even moreataxic. Therefore a litter tray wasplaced close to her bed and shewas helped into it. A urinary

catheter could have been placedto monitor urine output, but asshe could still posture to urinatein her tray output was monitoredthis way. Other concerns for apatient with reducedconsciousness include airwaymanagement, regular turning andocular lubrication if needed.

• Demeanour was monitoredclosely as the treatment and/orthe ethylene glycol could havechanged her mentation.

• Monitoring hydration as Mollycould become dehydrated if herfluid therapy was not adequate oroverhydrated if her kidneys failedto excrete adequate water. Thisincluded monitoring fluid intake,skin tent, packed cell volume(PCV), total solids (TS), urineoutput, mucous membranes andbody weight. Her chest was

Figure 1: A syringe driver should be used for continuousrate infusions to ensure both accuracy of dose and that theline is patent

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Keeping cats safe

Key point

The ethanol infusioncauses markedsedation andataxia and treatedcats need to bemanaged with attention to hydration,urination, turning, monitoring airwayand ocular lubrication.

Key pointCats with acute kidneyinjury, cardiac diseaseor being treated withhigh rate fluids mustbe monitored foroverhydration by regularlyauscultating the chest andchecking pulse and respiratoryrate.

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auscultated regularly for cracklesthat could indicate overhydration.

Nursing treatmentBlood tests were taken every 6 h tocheck for renal dysfunction andelectrolyte imbalances.

A urine sample was collected tocheck for the presence of calciumoxalate crystals, proteins andglucose suggesting acute kidneyinjury had occurred. In Molly's caseno evidence of kidney injury wasnoted. The CRI was maintained at 13ml/h for the time Molly spent withus. Medication was given at regularintervals by intravenous route forrapid onset under the direction ofthe veterinary surgeon.

A bandage was used to includeMolly’s foot to reduce the risk ofdistal swelling whilst the IV catheterwas in situ. Molly was hypothermicon presentation so a heat pad wasplaced underneath her blanket.Molly was monitored regularly(temperature, pulse, respiration) andit was important to auscultate thechest regularly, monitoring fortachycardia and crackles indicatingpulmonary oedema. Blood pressuremonitoring can also be included inthe regular observations.

Cat friendly practice prioritiesMolly was normally a feisty cat whocould be difficult to handle. This wasnot seen during her early treatmentbut as she began to improve sheresented examination more. Ablanket is a very useful tool when itcomes to handling fractious cats.For some cats gently placing ablanket over their head can calmthem and allow you to carry outprocedures such as catheter checksand flushes. In general, Mollyresponded to a ‘less is more’approach with patience and minimalrestraint (Figure 2). EMLA local

anaesthetic cream was used tofacilitate the regular blood sampling.Molly was kept in a cat only wardand had regular human interactionwhen she was happy to accept it.Comfort is always a priority. Addingextra vet beds, blankets or towels itcan make a cat’s stay much easier.As Molly was very depressed andsedated by the alcohol infusion shewas groomed and cleaned aroundher eyes and anus.

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Keeping cats safe

TipWhen restraininga cat a quiet,calm environmentand minimal ‘less ismore’ restraint ispreferable to a rushed andheavy handed approach.

Figure 2: Cats respond well to gentle, minimalrestraint, shown here for jugular bloodsampling, rather than a heavy handedapproach

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OutcomeMolly was successfully dischargedback to her day practice and madea miraculous recovery. We had anupdate 2 weeks after discharge tosay that Molly was recoveringreally well and didn’t have anypermanent renal issues. Molly wenthome a happy, lively and feisty cat.

DiscussionEthylene glycol is highly toxic andingestion is rarely witnessed. A testkit for diagnosis is available butmay be negative if the compoundhas already been metabolised.Diagnosis is usually made usinglaboratory tests revealingabnormalities such as acidosis withcalcium oxalate crystalluria and, ifuntreated, acute kidney injury.Prognosis for ethylene glycoltoxicity is grave but is verydependent on the timing fromingestion to treatment. A lot ofpeople do not realise whatchemicals pose a threat to cats.Cats are very inquisitive and like toinvestigate so if you have your carbonnet open take care to check fora cat. Household products alsocontain ethylene glycol so careshould be taken to store themcarefully.

ConclusionsTreating cats with ethylene glycoltoxicity can require intensivenursing and a clear understandingof the possible complications. Theclients need to be aware of thefinancial burden that they will incurfor a cat with a poor prognosis(particularly if the cat has acutekidney injury). However, if treatedpromptly and appropriately catscan survive as Molly showed.However, if her owners had waitedbefore bringing her to the surgerythe outcome would have been verydifferent.

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International Cat Care is the parent charity of theInternational Society of Feline Medicine (ISFM).Find out more about International Cat Care at

www.icatcare.org.

Online how-to videoswhat all cats would want their owners to watch

International Cat Care has produced 16 shortvideos to demonstrate correct cat care and helpowners with various cat care issues.

catcare

&treatm

entdemos

16videos

Available fromwww.youtube.com/icatcare

General• Apply a spot-on product • Apply ear drops and clean your cat’s ears• Apply eye drops or ointment• Brush your cat’s teeth• Clip your cat’s claws• Fit a collar for your cat• Give subcutaneous fluids to your cat

Giving a cat a tablet• Two people giving a tablet• Using a pill popper• Hiding a tablet in a treat• Crushing a tablet and mixing with water• Crushing a tablet and mixing with wet food

Diabetes• Home blood glucose testing for your cat• Collect your cat’s urine• Give your cat an insulin injection• Test your cat’s urine for substances like

glucose and ketones

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