Equine Emergencies: Recognition and First Steps

What do we define as an emergency?

• It's all about time... - 'a serious, unexpected, and often dangerous situation requiring immediate action'

- 'An emergency is a situation that poses an immediate risk to health, life, property, or environment. Most emergencies require urgent intervention to prevent a worsening of the situation, although in some situations, mitigation may not be possible and agencies may only be able to offer palliative care for the aftermath'

Emergency vs Urgency

When to expect an equine emergency?

• First opinion practice

• Day time

• Out of hours

• Referral hospital

• On duty at a horse event

• Racing, eventing, local show, endurance race

• Specific role/experience/training

By body system, what are the most common emergencies seen?

• Alimentary and Liver

• Emergency: Colic (1 in 10), abdominal trauma (eventration)

• Urgent: Choke (oesophageal obstruction), colic (potentially), poison/toxins, concentrate overload

• Respiratory

• Emergency: dyspnoea (obstruction), thoracic trauma (open thorax)

• Cardiovascular, spleen and blood

• Emergency: severe haemorrhage - wound or guttural pouch mycosis

• Musculoskeletal

• Emergency: fractures and some tendon and ligament injuries, wounds (laceration or puncture), atypical myopathy

• Urgent: wounds (laceration or puncture), synovial contamination, foot penetration, myopathy, laminitis

• Integumentary

- Urgent: wounds, burns

• Endocrine

• Reproductive

• Emergency: Dystocia, 'red bag' delivery

• Urgent: Retained placenta, foal not sucking

How can you ensure you are prepared for an equine emergency?

• Support - phone numbers!

• Colleagues/team

• Information/contacts

  • Advice: referral centres/university hospitals

• Facilities

• In house

• Referral options

• Numbers for local referral centre(s)

• Transportation contacts

• Disposal options

• Local fallen stock

• Private cremation

• Preparing Car (See Slide)

• Prepare yourself!

• Be assertive

• Project confidence

• Best professional demeanour

• Do not panic

• however bad things look initially many do very well as long as they receive the appropriate first aid

Describe the triage and prioritization step in an equine emergency.

• Over the phone

- Is this really an emergency?

• Often have to prioritise calls

- Information - history and signalment

- Guidance whilst they wait

• Remove all food from a colic/choke

  • If colic violent don't risk human safety *

  • Can walk in hand on a safe surface, if not

• Nail in foot (do not remove), stop further trauma

• Bleeding wound apply pressure and do not remove!

• Red bag delivery talk through rupture

Reminder** what is triage?

Sorting out and classification of casualties, determining priority of need and proper place of treatment, treatment decisions are not dependent on diagnosis

Describe the initial assessment or primary survey when you arrive at the scene of an equine emergency.

• Is this really an emergency?

• Take in whole situation

• assess risk, surroundings: don't get 'sucked in'

• 'Stand back' and observe the horse

• Are there humans at risk?

• they are priority

• Horses are dangerous, unpredictable, panic

• Clinical exam

• Patent airway?

• Vital parameters: TPR (- more RPT)

• Haemorrhage?

• Prioritise one animal over another?

• History

Describe the ABCD’s of cardiopulmonary resuscitation in equine emergency.

• Difficult due to size of patient

• Rare to be in this situation

• Rarely successful - more in a hospital/anaesthesia situation

• More practical in foals

• Establish an Airway

• Breathing for the patient

• Establishing Circulation

• Chest compressions - Right lateral recumbency

  • Knees in adults - behind elbow, widest point of chest

  • Hands in foals

• Drugs that should be administered

Describe upper airway obstruction difficulties in equines.

• Severe trauma/swelling/oedema of head/nasal passages

• Pharyngeal obstruction

• Severe strangles - Streptococcus equi

• Severe laryngeal dysfunction

• Laryngeal swelling/oedema

• Bilateral laryngeal paralysis

  • Trauma, hepatic encephalopathy, primary neurological, idiopathic

• Bypass the upper respiratory tract

• Emergency tracheostomy

Describe how an emergency (temporary) tracheostomy can be performed on equine patients.

Describe upper circulatory emergency issues in equines.

Describe the aspects of haemorrhage emergencies in equines.

• External

• Wound

• Dry bandage and apply pressure

• Care if decide to 'clamp' arteries

  • Be careful of neurological structures

• Guttural pouch mycosis

• Internal

• Abdominal/thoracic

  • e.g. Broad ligament haematoma in mares post-parturition

• Clinical signs of significant loss

• Depends on volume and rate of loss

• Tachycardia

• Tachypnoea & hyperpnoea indicative of significant hypovolaemia and hypoxaemia

• Mucous membrane colour depends on severity of loss

  • Pale/white

Describe the detailed or secondary survey - the clinical exam of an equine during an emergency

Why is it important to make the equine exam safe and why/when should sedation be considered?

• Human safety

• Assess risk

• Including your own

• Animal safety

• Calm and logical approach

• Assess as far as possible

• Don't rush to sedate

• Take control

• Adequate restraint

• Headcollar

• Twitch?

• Then consider sedation

Describe how sedation can be given to horses and when it is used.

**Note: can we do anything else before sedating the horse?

What should we do before we sedate and what can guide us to choosing the proper sedation?

What drugs are typically used for equine sedation?

Describe the features of Xylazine for use in equine sedation.

Describe the features of Detomidine for use in equine sedation.

Describe the features of Romifidine for use in equine sedation.

**Not a big analgesic

What is the main route of choice for sedation in equine patients?

• Route of choice is always intravenous

• Onset of peak action following IV = 2-5 minutes

• Allow time to take effect

• 'Ceiling effect' for intensity of sedation

• Further increasing dose increases duration, but has no effect on intensity

• Improve intensity using a combination with opioid

What are the side effects or disadvantages of a2-adrenoreceptor agonists?

• Hyperglycaemia

• Diuresis - not clear why?:

• Low renal threshold for glucose and this produces glucosuria (osmotic draw for water)?

• Alpha 2 receptors on renal tubules antagonise Anti Diuretic Hormone?

• Sweating

• Vasodilation, increased blood supply to skin

• Interpretation of bloods analyses

• significant changes in some parameters

• particularly decreases in PCV and total protein

• Hyperglycaemia

• No food until 'awake'

• Tendency to suffer oesophageal choke

• Bradycardia

• reduce cardiac output and respiratory depressants (care in foals)

• interpretation of colics - heart rate

• Arrhythmogenicity

• Reduce gastrointestinal motility (and secretions)

• Impair assessment of colic

• Repeated doses or continuous rate infusions

  • can cause colic e.g. large colon impactions

• Upper airway obstruction

• Muscle relaxation, can exacerbate pre-existing obstruction

• Impairs endoscopic assessment of upper respiratory tract

• Care in pyrexic horses

- Can induce tachypnoea (and can be antipyretic)

What opioids are often used in addition to sedatives in horses?

• Butorphanol - licensed for use in horses

- Sedation

• Always in combination with a2-agonist

- Analgesia

• Relatively poor analgesia, has claim for visceral analgesia

- Side effects

• Reduces small intestinal activity but minimal effect on pelvic flexure

• Cardiovascular and respiratory depression

• Alternatives include morphine and buprenorphine

Describe some routine sedation protocols used for equines.

Describe the dosage sedation protocols used for equines.

In horses which may requires alternatives or different sedatives, how can you provide a higher dose or alternative route?

Describe the role of Phenothiazines in equine medicine.

Describe the rational selection of antimicrobials.

Describe common antimicrobials used in equine medicine.

What are the main options for systemic analgesia in equines?

What is colic?

• Clinical syndrome associated with abdominal pain

• Classical signs: pawing, flank watching, rolling

• But also more generic signs: distressed, increased respiratory rate, sweating, odd stance, dull demeanour, not eating

• Can be misinterpreted by owner, and you!

• Analgesia central to its management

What are possible causes of colic, and what are syndromes similar to colic (But are not)?

What tests might be critical to establishing a colic diagnosis?

What are the different classifications of colic?

**Often we do not get a diagnosis → finding obstruction is the key as they will always need surgery

What are the different types of intestinal obstruction contributing to colic?

Small Intestine

• Mechanical obstruction

- Simple obstruction

• Intraluminal; Mural; Extraluminal

- Strangulating obstruction

• Internal and external hernias

• Pedunculated lipomas

• Intussusception; volvulus; fibrous bands and adhesions; arterial thrombosis

• Paralytic ileus (functional obstruction)

• Primary - grass sickness

• Secondary - Post operative; Anterior enteritis; Peritonitis

Large Intestine

• Simple or strangulating

Describe nasogastric intubation in horses.

• Hitting ethmoid turbinate may cause nose bleed - warn owners

What analgesia can be provided for colic?

• Non-steroidal anti-inflammatory drugs

• Phenylbutazone, flunixin meglumine, ketoprofen, meloxicam

• a2-adrenoreceptor agonists

• Xylazine, detomidine (care 10 x potency), romifidine (least analgesia)

• Opioids

• Butorphanol (relatively poor analgesia, duration~ 1.5 hours)

• Pethidine (rarely used), morphine, buprenorphine (duration ~8-12hrs)

• Antispasmodics: anticholinergic - not true analgesia

• Buscopan® (hyoscine butylbromide) ~

• Buscopan Compositum® (butylscopolamine and metamizole)

  • Metamizole - moderate analgesia, antispasm, antipyretic

What are the possible adverse effects of NSAIDs and what are the main ones indicated in colic?

• Inhibit COX enzymes preventing prostaglandin synthesis

• Peripheral effect

• COX 1 vs COX 2

• Possible adverse effects

• Nephrotoxicity

• Right dorsal colitis

  • and yes gastric ulceration, but RDC a more significant morbidity in the horse

When making our treatment and management plan, what questions should you ask?

• Don't need a diagnosis

• Can you do it?

• Do you need additional resources?

• Best treatment option?

• Referral?

• Is the client on board?

• communication

What owner factors might contribute to your management and treatment plans?

• Clear communication

• Offer options

• Finance

• Insurance?

• Referral an option?

• What was/is this horse expected to do

• Race

• Retire in paddock

• Emotional attachment

When considering euthanasia in horses, what methods and procedures should you follow?

• Communicate clearly and obtain signed consent

- Empathy

- Discuss insurance

- Discuss what will happen during euthanasia and just after

- Discuss disposal and possible post mortem, mane, tail, shoes

• Consider location

- Privacy and noise

- Surface and hazards

- Extraction for disposal

• Adequate restraint

- Sedation?

• What could go wrong.......

- Spare bottle Somulose/bullet

- Catheter comes out?

- Bystanders?

What medication is used to perform equine euthanasias and what are the main safety considerations?

How are equine euthanasias performed?