Abdominal Equine BRAD Flashcards
What is the sedation for a horse?
a) Caudal Epidural - Xylazine & Lignocaine diluted:
C1-2,
20-18G 1.5/3inch,
20 min – 5hrs
b) Local Anaesthetic - Paralumbar Laparotomy: Paravertebral: T18-L3
What are the indications for abdominal surgery?
- Exploratory laparotomy: Abdominal pain, weight loss, fever
- Cryptorchidism
- Ovariectomy
- Nephrectomy
- Haemoperitoneum
- Biopsies
- Adhesiolysis
- Hernia repair
- Abdominal trauma
- C-Section
- Uterine Torison
- Cystolith
- Septic umbilical remnants
What are the principles of abdominal surgery?
- Surgical environment
- Clip 40 blade
- 3 step surgical scrub: 5 min povidone iodine scrub
- Alcohol 3 step wipe
- Povidone iodine solution 3 step wipe
- Drapes and Gowns
- Double glove
- Suction
- Anaesthetic ventilator
- Blood pressure monitoring
What is a Ventral Midline Laparotomy?
Location: 20-30cm incision cranial to umbilicus
Process:
Skin and subcutaneous: 25 blade, RINSE GLOVES
Linea alba: New 25/10 blade and dressing forceps, strip parietal peritoneum –> Exteriorise colon in train
Visualise: GIT
– Caecum (1st), Large colon, trace SI from ileocaecal ligament proximally to duodenocolic fold
How to test Intestinal viability?
- Clinical Assessment: 53% Accuracy
a) Serosa/mesentery wall colour & thickness b) Mucosal colour (85% black LC mucosa die)
c) Mesenteric arterial pulse
d) Spontaneous/evoked motility (Neural plexus 1st affected)
e) Haemorrhage from enterotomy - Fluorescein: 11mg/kg IV woods lamp – better for LI (large intestine) (53% accuracy)
- Surface Oximetry: Serosal ppO2 <20mmHg = poor prognosis
- Doppler U/S: Okay for venous obstruction
- Luminal pressure: >30cmH2O survive
- Histopathology: LC (left colon?) mucosal cell loss, crypt loss, I:C ration <1 (>3 = non-viable)
How to do closure?
Abdominal - Linea Alba
Caudally is 1cm Thick, cranially is 0.3cm thick, healing linea alba returns to normal tensile strength 60-80 days
Material: 3 or 5 Vicryl/safil - Strongest synthetic absorbable, 14-21d strength
–Bite: 1.5cm from edge 1cm apart
Pattern:
a) Simple continuous: 50% Sx (Surgery?), ↓ complications
– fails at fascia.
- Start at each end and meet in the middle
b) Inverted cruciate: 25% Sx, failure at suture
Incisonal Closure:
a) Subcutaneous closure: Simple continuous, reduce dead-space, bury knots
b) Intradermal: ↓ infection rates (In humans)
c) Skin staples: Faster, ↓ vascular compromise & infection rate BUT removal required
Describe how to handle a ruptured bladder?
Hosts: Colt foals, 3-4 days old
Approach: Caudal Laparotomy
CS: Straining/posturing to urinate, progressive belly distension & lethargy
Consequences: Severe Electrolyte imbalances, heart arrhythmia’s, death
Describe infected umbilicus AKA Navel Ill
Hosts: In the several weeks after birth (Infection in utero or birth)
CS: Swelling/urine from umbilicus, depressed, fever, septic arthritis
Equine Umbilicus is Made up of:
2x umbilical a.,
umbilical v., urachus
Tx: Resect urachus & affected a.
What is a Laparoscopy?
Process: Rigid laparoscope placed via stab incision & abdomen is inflated with CO2
Advantages:
- Standing
- ↓ Hospitalisation
- ↑ Cosmetics
- ↓ Pain
Disadvantages:
- Expensive
- Slower procedures
- Limitations (Colic)
Complications:
- Perforation of viscus
- Retroperitoneal CO2
What are the Complications of Abdominal Surgery?
- Incisional infection
10-37% after 1st laparotomy
CS: Fever, incisional pain, drainage, 3-14d post-op sx
Risk Factor: Sx time (>2hr = 2x risk),
Repeat lap, enterotomy, suture pattern/type, Sx technique (regown, change gloves), >300kg BWT - Adhesions
5-33% incidence
Hosts: high in foals & Small intestine cf. (chronic) Large intestine disease
RF (Risk Factor): SI Disease, Resect/Anastomosis , enterotomy, Repeat laparotomy, glove powder, serosal drying, surgery time - Incisional Hernia
- Post-op Ileus
- Endotoxemia
- Peritonitis
- Incisional dehiscence
Describe a Hernia
RF:
- 25% horse with incisional infection
- Violent recovery
- Suture technique/choice
- Uncontrolled exercise post surgery
Congenital: Umbilical/inguinal – risk of intestinal incarceration
Acquired: Traumatic, Post-op, inguinal
– Need to wait 4-6m before surgery for strength
Closure:
a) Direct suture: Stainless steel or 5 vicryl in horizontal mattress
b) Non-absorbable mesh polypropylene: Retroperitoneal fixture
- Issues: Poor handling, adhesions, sinus tracts formation
Umbilical Hernia repair:
Recommended:
Elliptical incision → resect hernia → 2-5 Vicryl inverted cruciate/continuous w/ close bites to avoid omentum to herniate through incisional bites → invert hernia sac → Appose hernia ring → Absorbable skin suture
Alternative method:
Multiple elastrator bands around base of hernia under general anaesthesia
- Issues: Sloughing, intestinal eventration, enterocutaneous fistula *NOT RECOMMENDED
