Consitpation, Tenesmus, Dyschezia, and Fecal incontinence Flashcards
Define constipation
- Constipation = infrequent or difficult evacuation of dry, hard feces
Define Obstipation
= severe form of constipation where faeces is so hard and dry that the animal is no longer able to defecate. Requires medical intervention
Define Tenesmus
= ineffectual and painful straining at defecation or urinations. Results from disease of large intestine or lower urinary tract.
Define Dyschesia
difficult or painful evacuation of faeces. Result from disease of anal and perianal tissues
Define Fecal incontinence
= defecation without conscious control
What is the function of the LI?
- Function: absorption of water and electrolytes (ascending and transverse colon) and storage of faeces (descending colon)
Describe Haustral contractions
= contractions of circular and longitudinal smooth muscle of colon results in accumulation of colonic contents in unstimulated segments.
Mixing increases exposure of contents to colonic mucosa for maximum water and electrolyte absorption while propelling ingesta down the length of the colon
Define Mass Movements
- intense propulsive activity down entire length of colon to propel fecal matter toward anus for defecations.
- Occur a few times daily most commonly following a meal and stimulated by autonomic nervous system.
Explain the anatomy and nervouse supply to the anal sphincter
Anal sphincter – internal sphincter composed of smooth muscle (direct extension of circular smooth muscle of rectum) and external anal sphincter composed of striated muscle
Internal sphincter remains contracted most of the time and is responsible for fecal continence.
Internal sphincter receives its parasympathetic nervous supply from sacral spinal cord segments via pelvic nerves
Sympathetic innervation is from lumbar spinal cord segments via hypogastric nerves.
Sympathetic stimulation = contraction of internal anal sphincter
Parasympathetic stimulation results = relaxation.
External anal sphincter is under conscious control and allows animal to resist and prevent defecation from occurring.
External sphincter is innervated by somatic efferent nerve fibers, originating in the cranial sacral spinal cord segments and coursing through the pudendal nerves.
What can be the potential signalment of tenesmus?
Signalment
Malformed sacral spinal cord:
- Bulldogs
- boston terrier
- manx cats
- GSD – perianal fistulas -> dyschezia and constipation
- Megacolon occurs in middle-aged male cats
Male dogs - prostatomegaly
What are the inflammatory or infectious causes of tenesmus and dyschezia?
Inflammatory or infectious
- IBD
Dietary indiscretion - Intestinal parasitism
- Idiopathic colitis
- Pythiosis
- Bacterial or fungal colitis
What are the obstructive causes of tenesmus?
Obstructions
Intraluminal:
- Colonic neoplasia
- Foreign body strictures
Extraluminal:
- Pelvic fractures
- Masses
- Organomegaly
What are the causes of dyschezia?
- Perianal fistulas
- Perineal hernia
- Anal/rectal neoplasia
- pseudocoprostasis
What are the physical exam findings of a patient with tenesmus?
- Underlying systemic disease:
- Weakness
- Anorexia
- Increased water loss (polyuria)
- Abdo palpation -> distended colon with hard faeces
- Anus- fecal hair mats (pseudocoprostatitis), masses, and perianal fistulas.
Digital palpation of Rectum and distal colon:
- hard, dry faeces,
- colonic or rectal masses
- foreign bodies
- pelvic fracturs
- enlarged sublumbar lymph nodes
- prostatomegaly in male dog
- perianal hernias
- evidence of anal sac disease
What are the diagnostic tests used for patients with tenesmus?
- CBC
- Serum biochemistry
- Urinalysis
Abdominal rads:
- colonic distension
- masses
- foreign bodies
- LN enlargement
- Prostatomegaly
- pelvic fractures
Abdo US:
- intraluminal or extraluminal masses
- prostatomegaly
- enlarged lymph nodes
Colonoscopy:
- may reveal colonic neoplasia
- perineal hernias
- diverticula
- strictures.
What can be common history findings of patients with tenesmus?
- Duration of signs
- Frequency of attempts
- Diet – fibre content
- Anorexia – decreased access to food or water
- Hx of pelvic trauma or abdominal surgery
- Dyspnea – reluctance to defecate
What are some important questions to ask for patients with tenesmus?
Urinate -exclude LUT :
- Normal stream?
- Dripping?
- Appearance:
Faeces:
- Normal?
- Thin, ribbonlike or small amounts? -> obstructions
- Excessive groomins of regions?
- History of trauma/fractures?
Cats with tenesmus or dyschezia:
- Vocalise or defecate outside the litter box
- Timing :
- Prior to defecations = obstruction
After defecations = irritation/inflammation
What are important physical exam features to differentiat tenesmus from lower urinary tract disease or lower GIT problem?
- Palpate bladder to rule out obstruction
- Inspect anus and perianal region to rulte out perianal fistulas, anal sac rupture, and faecal hair mats causing pseudocoprostasis
Digital rectal palpation:
- uroliths in urethra
- Prostatomegaly in male dogs
- Rectal masses
- Perineal hernia
- Anal sacculitis
- Sublumbar lymph node nelargement
- Pelvic fractures
Faeces – absent, scant, bloody consistente with inflammatory disease
What diagnostic tests can be performed for tenesmus and dyschezia?
- CBC, biochemistry, urinalysis to exclude systemic disease
- Fecal flotation – GI parasites
- Radiographs and ultrasound: – rule out extraluminal compression of colon
- foreign body
- pelvic fracture
- olonic masses
Colonoscopy and proctoscopy:
- identify mases, foreign body strictures
- Biopsys for inflammation, infection, or neoplasia
What are the causes of fecal incontinence due to a damaged anal sphincter?
Damaged anal sphincter (non-neurogenic sphincter incompetence):
- Cauda equina syndrome
- Damage to pudendal nerve
- Sacral spinal cord trauma
- Neoplasia
- Compressive lesions
- Degenerative myelopathy
What are the causes of fecal incontinence due to disrupted nervous supply to anal sphincter?
Disruption of nervous supply to anal sphincter (neurogenic incompetence):
- Anal trauma or surgery
- Anal neoplasia
- Damage to levator ani
- Coccygeus muscles
Explaine reservoir incontinence
Reduced capacity or compliance of rectm (reservoir incontinence):
Pet aware of urge to defecate, but conscious control of defecation is overwhelmed by presence of colorectal disease causing irritation, decreased storage capacity of rectum, or overwhelming fecal volume.
What are some common history findings and questions to determine in a patient with faecal incontinence?
- Establish is animal is aware of defecation and assuming normal posture to defecate
- Awareness, diarrhea, increased frequency, and mucus/blood in feaces suggests => colorectal disease and reservoir incontinences
- Behavioural problems = still normal posturing, frequency, and consistency
- Reservoir incontinences -> attempt to get outside to defecate but unable to retain faeces, and defecate close to the door outside
- History of recent trauma/surgery -> anal sphincter damage
- Neurogenic sphincter incompetence- loss of tail wagging, abnormal tail carriage, hind limb ataxia or weakness, decreased HL spinal reflexes, concurrent urinary incontinence
