Investigation of the colic case Flashcards
Colic is a term used to describe?
Abdominal pain
- it is a clinical sign not a disease or diagnosis
What are the clinical signs of colic?
- Flank watching
- Lying down
- Pawing at the ground
- Rolling
- Repeatedly getting up and down
- Violently thrashing around
Describe the pathophysiology of colic
- Anything that prevents the normal progression of intestinal contents
- Simple obstruction
- Strangulating obstruction
- Intravascular occlusion of the blood supply
- The most severe forms will result in shock
Shock due to colic is the result of?
- Loss of the vascular supply to the mucosa
- Absorption of endotoxins into the circulation
- Systemic inflammatory response system (SIRS)
What are the different colic classifications?
- Spasmodic
- Impactions
- Gas distention
- Obstructions: simple and strangulating
- Non-strangulating infarction
- Inflammation: enteritis, colitis
- Idiopathic
What initial advice can be given over the phone to the owner in colic cases?
- Put the horse in a well bedded stable (may not be possible in all cases)
- Remove any buckets / feed / anything it could potentially injure itself on
- Let the horse roll if it wants to
- A short period (10 minutes ) of walking exercise is fine but nothing longer than this should be undertaken without veterinary examination firs
How must a violently painful colic be initially managed?
- Quickly assess the horses heart rate (do this before administering any medications)
- Administer intravenous xylazine (200mg for a 500kg horse): provides analgesia and sedation
- Obtain a succinct history
- Perform a clinical exam
What are the key points of information to gather when history taking?
- Signalment, use & pregnancy status
- Stereotypic behaviour
- Horse’s usual management: stabling, turnout and feeding
- Routine parasite prophylaxis & dental care
- Any changes in feeding, turnout or premises
- Any ongoing medical problems / medications
- Previous history of colic/ diagnosis and treatment for this
What are some specific questions to ask for a colic epidose?
- Signs of colic observed
- When these signs started or when the horse was last seen to be normal
- Feed intake & faecal output over last 24hours
- Any diarrhoea
- History of equine grass sickness on the premises
Describe the initial observation and evaluation of a colic case
- Any signs of disturbance of the bed / covered in mud?
- Skin abrasions?
- Gross abdominal distension?
- Observe the horse for a short time – does it have colic?
- Beware: late stages of severe colic
- Heart rate (28-44bpm normal)
- MM colour, CRT
- RR (12-15 bpm normal)
- Temperature (37.5-38.40C normal)
- Digital pulses
What are some causes of ‘false colic’?
- Musculoskeletal
- Respiratory
- Urogenital
- Hepatic
- CNS
- Endocrine
- Cardiovascular
- Haemolymphatic
Describe abdominal auscultation of colic cases
- Palpation is of no use in horses
- Auscultation to determine whether the normal propulsive / mixing sounds are present is useful (intestinal borborygmi)
- Listen on both sides of the abdomen for around 1 minute at each quadrant:
• Normal (++)
• Reduced (+)
• Absent (-)
• Hypermotile (+++) - Will be reduced following administration of sedation drugs
What is one of the most useful diagnostic test in the colic case?
Rectal exam
What are the main considerations before performing a rectal exam?
Safety is important • Your safety (kicks) • Minimising the risk of rectal tears \+/- sedation (xylazine) \+/- twitch application \+/- Administration of butylscopolamine (Buscopan®)
What structures will be felt on a rectal exam?
- Small intestine – inner tubes of bike tyres
- Large intestine – pelvic flexure / taenia / direction of these
- Caecum – vertical band
- Don’t forget the small colon!
Name some abnormal findings on a rectal exam
- Distended Small Intestine
- Pelvic Flexure Impaction
- Left Dorsal Displacement
- Right Dorsal Displacement
- Large Colon Torsion
- Caecal Impaction
- Small Colon Impaction
Name some other diagnostic tests that can be used?
- Abdominocentesis
- Nasogastric intubation
- Haematology
- Abdominal ultrasound
What is assessed using abdominocentesis?
Peritoneal fluid - change in the gut wall will result in a change in this
Describe the technique for Abdominocentesis
• Ventral midline • Most dependent part of abdomen • +/- clip, scrub • 18 g, 1.5 inch needle May need spinal needle if fat!
Describe the visual assessment of peritoneal fluid
Quantity – note if large amount
Colour – normal: straw coloured
Clarity – normal: clear
Ingesta present – enterocentesis / rupture
Describe the laboratory assessment of peritoneal fluid
- Total protein (<20g/L)
- White blood cell count (<5x109/L)
- Lactate (<2mmol/L)
What is important to remember when performing nasogastric intubation?
- Horses cant vomit
- The stomach will continue to secrete fluid so if there is an obstruction of normal flow of ingesta, large quantities will build up
- Rupture of the stomach can occur ultimately
Describe the nasogastric intubation diagnostic test
> 2L net reflux significant
Why else is nasogastric intubation good/used for?
- Decompression will also provide some pain relief
- Can be used to administer fluids as part of medical therapy
Describe haematological testing for colic cases
- Packed cell volume (normal 35-45%)
- Systemic total protein (normal 60-70g/L)
- Systemic lactate (normal <2mmol/L)
- Other tests may be indicated e.g. white blood cell count, biochemistry
What are the used of abdominal ultrasonography in colic cases?
- Very useful in foals
- Increasingly used in adult horses in practice
- Per-rectum / per-cutaneous
What is one of the most common causes of colic in a foal?
Meconium impaction
Ruptured bladder can cause colic signs too
Describe colic cases in donkeys
- Usually present with signs of dullness: uncommon to show marked signs of colic
- Impaction colic common
- Rectal examination can be performed safely
- They can have a lot of retroperitoneal fat: spinal needle may be needed for abdominocentesis
- Always check for dental abnormalities in impaction cases
Equine dysautonomia is also known as?
Equine grass sickness
What is the causative agent of equine grass sickness?
Suspected to be toxico-infection with C. botulinum type C
Describe equine grass sickness
- Frequently fatal form of intestinal disease (paralytic ileus)
- Acute, sub-acute and chronic forms
- Diagnosis based on key clinical signs +/- biopsy (definitive)
