Management of iatrogenic injuries and other equine emergencies

Question 1

What does a iatrogenic injury mean?
Examples?

Answer 1

• Injury caused by medical (veterinary) examination or treatment
  E.g.
• Nasal haemorrhage during nasogastric intubation / endoscopy
• Rectal tears during rectal examination
• Evisceration following castration
• Adverse drug reaction
• Anaesthetic death

Question 2

What are complications of nasogastric intubation?

Answer 2

• Haemorrhage (common)
• Oesophageal perforation (uncommon)
• Inhalational pneumonia (uncommon)

Question 3

What can be done to minimise risk of damage with nasogastric intubation?

Answer 3

• Use an appropriate tube
• Ensure the horse is restrained
• Pass the tube along the ventral meatus
• Never force the tube
• Ensure it is placed in the oesophagus / stomach before administering fluids

Question 4

What should be done if there is a haemorrhage?

Answer 4

• Can be alarming to the owner = Mention possible complication
• Leave the horse quietly for 5-10 minutes
• Haemorrhage will usually stop by this time
• Do not pack the nasal passages
• Further assessment required if haemorrhage continues (uncommon)
• Endoscopy
• Clotting profiles

Question 5

When would you suspect oesophageal perforation?

Answer 5

• If blood on tube (in absence of epistaxis)

Question 6

How would you assess / treat oesophageal perforation?

Answer 6

• Endoscopic assessment of the oesophagus +/- radiography
• Full thickness perforations have poor prognosis

Question 7

How does inhalational pneumonia occur?

Answer 7

• Passage of nasogastric tube into the trachea

Question 8

What happens with water inhalation?

Answer 8

• Small quantities not usually a problem
• Large quantities can result in pulmonary oedema / inhalational pneumonia

Question 9

What happens with liquid paraffin inhalation?

Answer 9

• Severe lipoid pneumonia
• LIFE THREATENING

Question 10

What are the biggest complication of rectal examination?
What increases this risk?

Answer 10

• Rectal Tears
• Increased risk:
• Arabians
• Stallions / colts
• Colics
• Fractious horses
• Using an ultrasound probe

Question 11

How can you reduce risk of rectal tears on rectal examination?

Answer 11

• Be in a safe position
• Ensure the horse is restrained
• Sedate if necessary +/- butylscopolamine
• Never push against the rectum if the horse strains

Question 12

When would you suspect a rectal tear?

Answer 12

• Blood on rectal sleeve

Question 13

What would your initial action to a rectal tear be?

Answer 13

• Inform the owner
• Sedation
• Butylscopolamine
• +/- epidural anaesthesia
• Evaluate rectal mucosa - Lubrication and lidocaine
• Proctoscopy
• Determine the location and grade

Question 14

What are the grades of rectal tears?

Answer 14

• Grade 1 = Mucosa & submucosa torn
• Grade 2 = Muscularis only
• Grade 3a = Mucosa and muscularis (serosa intact)
• Grade 3b = Mucosa and muscularis (tear into mesocolon) - further caudal
• Grade 4 = All layers torn

Question 15

How would you treat each grade of rectal tear?

Answer 15

• Grade 1 = medical management
• Grade 2 = medical management
• Grade 3+4 = Medical / surgical management (euthanasia?)

Question 16

What is medical treatment of rectal tears?

Answer 16

• Broad spectrum antimicrobials – penicillin / gentamicin
• Flunixin meglumine
• Tetanus status
• +/- epidural anaesthetic and packing of rectum

Question 17

What are surgical management of rectal tears?

Answer 17

• Direct suturing - single handed long needle
• Placement of a rectal liner - GA
• Temporary diverting colostomy - May require 2 GA ££

Question 18

What are other iatrogenic injuries / accidents?

Answer 18

• Adverse drug reaction
• Anaphylaxis
• Intracarotid drug administration
• Perivascular injections
• Injection site abscess
• Iatrogenic synovial sepsis
• Broken needles
• Catheter accidents
• Anaesthesic-related complications

Question 19

What are golden rules of trapped horses?

Answer 19

• Trapped horses can be unpredictable = Offering food and keeping a companion nearby may help
• Be aware of your own and others’ safety - Work from the spine side of the horse
• Have control of the horse’s head - Place a headcollar
• Be prepared to sedate / anaesthetise
• Never release the horse unless it has somewhere safe to go
• Always plan an exit route for you and others

Question 20

What should be done after freeing a horse?

Answer 20

• Full clinical exam
• Assessment + Tx of -
• limb fractures
• wounds
• head / ocular injuries
• dehydration / hypothermia
• acute haemorrhage
• URT/LRT inflammation

Question 21

What injuries need to be considered with stable fires?

Answer 21

• Smoke inhalation - black sut around nose
• Skin burns
• Corneal ulceration
• Hypovolaemia ‘burn shock

Question 22

How would you assess a horse initially after a stable fire?

Answer 22

• Lukewarm water; remove rugs
• Sedation / anxiolytics if required
• Administer flunixin
• +/- oxygen
• IV catheter +/- tracheostomy
• Referral / euthanasia may be needed

Question 23

What should be done with less severe burn cases?

Answer 23

• Cool skin
• Clip hair
• Lavage (0.05% chlorhexidine solution)
• Water (not oil) based antimicrobial ointment = Silver sulfadiazine

Question 24

With wounds what would be your initial advice to the owners?

Answer 24

• Control haemorrhage: = Dressing, Pressure
• Do not move the horse if it is very lame unless in imminent danger
• Minor wounds in low-risk areas = telephone advice may be all that is needed
• More severe cases = tell owners not to apply anything to the wound

Question 25

What history would you want to know with wounds?

Answer 25

* Tetanus status

Question 26

With wounds what would you assess on clinical exam?

Answer 26

PRIOR TO EXAM = stop haemorrhage + stabilise limb * Shock/ other injuries * Assess stance / weightbearing * Vital parameters * Blood loss * Other smaller wounds

Question 27

What would you do with the wound?

Answer 27

* Sedation * Assess - age of wound, contamination + location * Apply sterile gel * Clip + clean around site

Question 28

What would you use to lavage the wound?

Answer 28

* 0.05 chlorohexidine * 0.1 povidone iodine -35-60ml syringe w 18/19G needle

Question 29

Whilst assessing wounds what would you check?

Answer 29

* Sterile gloves, use finger / sterile probe - Depth and direction - Foreign material - Subcutaneous pockets - Bone / tendon exposure * Joint / tendon sheath? * Thoracic / abdominal organs? * Trachea / oesophagus?

Question 30

What would your considerations with injuries be?

Answer 30

* Time since injury * Contamination / infection * Tissue defects * Tissue flaps / viability * Patient compliance * Is GA needed

Question 31

What is ideal conditions for wound suturing?

Answer 31

* <8h old * Healthy tissue * Eyelids, nostrils, lips (full thickness)

Question 32

What can be used for local anaesthesia with wounds to suture? What nerve block could you do?

Answer 32

* Mepivacaine * Lignocaine - regional nerve block - Ring / L-block

Question 33

How would you suture a horse?

Answer 33

* Remove necrotic tissue * Preserve tissue flaps * Skin staples = quick + easy - NO TENSION * Skin suture = 2-0 - 0 USP monofilament = polypropylene * SC suture = 2-0 USP, absorbable = poliglecaprone * Drain * Dress / bandage

Question 34

What are other ongoing management of wounds?

Answer 34

* Analgesia / anti-inflammatories - IV at first, followed by oral * Antimicrobials - IM followed by oral * Tetanus toxoid booster * Box rest * Suture / staple removal - 10-14days * Dressing / bandage change - as often as needed (exudate)

Question 35

How is secondary intention healing carried out?

Answer 35

* Sterile hydrogel + non-adherent, absorbent dressing * Bandaging of distal limb

Question 36

What are complications of wounds?

Answer 36

* Synovial sepsis / fracture (missed initially) * Sequestrum formation - Where cortex of the bone exposed * Dehiscence - wound bursting open * Foreign material remains in situ - Be careful if wood involved * Bandage sores

Question 37

What must a wound bed be for a successful graft?

Answer 37

* Vascularised * No necrotic tissue * No overt infection * No evidence of delayed wound healing - Sequestrum - Foreign body

Question 38

What are indications for grafting?

Answer 38

* Traumatic injuries * Non- / slow-healing granulating wounds * Adjunct to management of skin neoplasia * Extensive skin burns * Deformity-causing scarring

Question 39

How is pinch / punch grafting carried out?

Answer 39

* Well lit, quiet * Sedation * Equipment ready * Donor site prepared = - Neck - +/- abdomen - Clipped, local anaesthesia - Skin preparation * Grafting site prepared = Cleaned & superficial debridement already performed Placing grafts * Start at the lowest site (prevents haemorrhage obscuring sites) * Make a pocket in the granulation bed - No 15 scalpel blade * Tuck grafts into each pocket * Non-adhesive dressing, bandage * Box rest * Change bandage in 5-7 days

Question 40

What do you need to identify for referral horses?

Answer 40

* Identify cases needing - - More intensive care - Detailed investigations - Surgical intervention * Initiate honest discussion with owner / carer * If appropriate start arranging possible transport * If referral is declined, the client should be aware of potential outcomes

Question 41

What should be done if considering referral?

Answer 41

* Good communication between vet, referral centre and owner