Equine Emergencies Flashcards
What is meant by ‘iatrogenic’?
Caused by vet
Give some examples of iatrogenic injuries in horses
- Nasal haemorrhage during nasogastric intubation/endoscopy
- Rectal tears during rectal exam
- Evisceration following castration
- Adverse drug reaction
- Anaesthetic death
Give some possible complications from nasogastric intubation
- Haemorrhage (common)
- Oesophageal perforation (uncommon)
- Inhalational pneumonia (uncommon)
How can you prevent complications when doing nasogastric intubation?
- Use an appropriately sized stomach tube, lubrication and ensure it is not roughened/damaged
- Ensure horse is suitably restrained (twitch/sedation if needed)
- Make sure tube is passed down ventral meatus
- Never force the tube, ensure it is placed properly within the oesophagus/stomach before administering fluids
What should you do if a haemorrhage occurs when you are passing a nasogastric tube?
- Explain to owner that this is a possible complication
- Leave horse quietly for 5-10 mins (will spontaneously stop in most cases. Don’t pack nasal passages-horse will snort and make situation worse)
- Further assessment required if haemorrhage continues (uncommon)-endoscopy, clotting profiles
When may you suspect oesophageal perforation when doing nasogastric intubation?
If blood seen on nasogastric tube (where no nasal haemorrhage is evident)
How would you further assess a possible oesophageal perforation?
Endoscopic assessment of oesophagus +/- radiography
Full thickness perforations -> poor prognosis
How does iatrogenic inhalational pneumonia occur?
- Inadvertent passage of nasogastric tube into trachea
- Water inhalation (small amounts ok, nut large quantities can result in pulmonary oedema/inhalational pneumonia)
How would you identify an iatrogeenic rectal tear?
Blood on rectal sleeve
What should you do if you identify a rectal tear when doing a rectal exam?
- Inform owner
- Sedate horse
- Administer butylscopolamine +/- epidural anaesthesia
- Evaluate the integrity of the rectal mucosa
- Protoscopy is useful if endoscope is available
- Determine location and grade of tear
What are the grades of rectal tears?
How would you treat them?
Grade 1: mucosa and submucosa (no particular concern, treat medically or not at all)
Grade 2: muscularis (can be treated medically)
Grade 3a: mucosa, submucosa, and muscularis (not midline)
Grade 3b: mucosa. submucosa, and muscularis (midline)
Grade 4: all layers
Grade 3-4 can be treated medically or surgically
How can you medically treat rectal tears?
-Broad spectrum antibiotics-penecillin/gentamicin
-Flunixin meglumine 1.1mg/kg IV
-Check tetanus status
+/- epidural anaesthetic an dpacking of rectum
What initial advice would you give to an owner of a horse with a wound?
- Control any profuse haemorrhage by placing a dressing/clean dry material over the site and maintain pressure if possible
- Don’t move horse if severely lame unless it’s in imminent danger
- For what sounds like minor cases, phone advice may be all that’s needed
- For more severe cases, tell owner not to apply anything to wound before you assess it
What should you check when assessing a wound?
Horse’s tetanus status
Check for shock
How should you assess a wound?
+/- sedate horse
- Assess age of wound/degree of contamination and its location
- Apply sterile gel, clip and clean around it
- Remove gel and lavage the site using sterile polyionic fluids/ 0.05% chlorhexidine/ 0.1% povidone iodine. Make sure pressue of lavage is under 10-15psi (35/60ml syringe and 18/19G needle)
- Determine depth and direction of wound, presence of foreign material, SC pockets, bone/tendon exposure
- Is wound near a joint/tendon sheath?
- Could it involve penetration of thoracic/abdominal organs or other vital areas eg trachea?
Which kinds of wounds should you suture?
- <8 hrs old and have healthy looking tissue at the wound margins
- Are around the eyelids, nostrils and lips (full thickness)
How should you approach suturing wounds?
-Suitable restraint (twitch/sedation)
-LA (regional nerve block, ring block)
-Remove necrotic/non-viable tissue
-Skin staples (should not be placed where there is any tension)
-Suturing (+/- stenting)
+/- drain
+/- dressing and bandaging
What is secondary intention wound healing?
Wound edges cannot be brought together/extensive tissue loss, wound is allowed to granulate
How is secondary wound healing carried out?
- Apply sterile hydrogel and non-adherent, absorbent dressing
- Bandage distal limb +/- splint
- Ongoing wound management is important (can take a long time)
- Some wounds may be suitable for tertiary healing (delayed priamry closure) or skin grafting
Is horse skin elastic or not?
Very inelastic
What is tertiary healing (delayed primary closure)?
The wound is initially cleaned, debrided and observed, typically 4 or 5 days before closure. The wound is purposely left open but later closed
Examples: healing of wounds by use of tissue grafts
What ongoing management shoudl be applied to wounds?
-Analgesia/anti-inflammatories (IV meds followed by oral)
-Antimicrobials (IV/IM followed by oral, eg trimethoprim sulphonamides)
+/- tetanus toxoid/tetanus booster
+/- box rest (beware colic)
-Timing of suture/staple removal (usually 10-14 days)
-Frequency of dressing/bandage changes (depends on amount of exudation)
Give some possible complications of wound management
- Synovial sepsis/fracture (missed initially)
- Bone sequestrum formation (where bone cortex is exposed)
- Wound dehiscence
- Foreign material remains in situ
- Bandage sores (eg over hock/carpus)
When dealing with a trapped horse, which side of the horse should you work from?
Spine side of the horse is safest
Never position yourself where you could get kicked/butted by horse’s head
Ensure you have control of horse’s head (head collar/halter)
What should you do after freeing a trapped horse?
Full clinical exam
Give some common injuries that may occur when a horse is trapped?
- Limb fractures
- Wounds
- Head/ocular injuries
- Dehydration/hypothermia
- Acute haemorrhage
- URT/LRT inflammation
Which injuries should you consider with stable fires?
- Smoke inhalation
- Skin burns
- ‘Burn shock’
How should you initially assess a horse that has been in a stable fire?
-Stop any burning-cool affected areas with lukewarm water and remove rugs/blankets
-Sedate/anxiolytics if required
-Administer flunixin 1.1mg/kg IV (NSAID)
+/- administer oxygen
-Severe cases: may need catheter placement +/- tracheostomy (URT inflammation, burn shock)
-Referral/euthanasia may need to be considered
How should you assess burns?
- Full clinical exam (check for involvement of eyes and other structures eg joints/tendon sheaths)
- Assess extent of injury
- Assess depth of burns injury (depth=degree of burn)
- Determine if referral/euthanasia should be considered
How should you treat less severe cases of burns?
- Cool skin with cold water (4oC) for 1 hour
- Clip hair and lavage with 0.05% chlorhexidine solution
- Apply a water (NOT oil) based antimicrobial ointment eg silver sulfadiazine
When should you not use skin staples?
Around sites where there is any tension
