Surgical affections of large intestine

Surgical affections of large intestine are Intestinal obstruction, Caecal dilatation or torsion, Twist or rotation of the colon in horses, Rectal prolapse, Congenital malformation of large intestine, Tumors of Rectum, Paralysis of Rectum, Rectal tear, Colic in horses etc.

Surgical affections of large intestine in animals are-

1. Intestinal obstruction
2. Caecal dilatation or torsion
3. Twist or rotation of the colon in horses
4. Rectal prolapse
5. Congenital malformation of large intestine
6. Tumors of Rectum
7. Paralysis of Rectum
8. Rectal tear
9. Colic in horses

Intestinal obstruction

Intestinal obstruction of large intestine is infrequent in ruminants but common in dogs and cats. Mechanical obstruction may be intra-luminal or extra-luminal.

Intra luminal

• Fecalith
• Impacted ingesta
• Foreign bodies
• Parasitic infestation

Extra luminal

• Stenosis
• Adhesions
• Fibrous bands
• Hernia
• Abscess
• Neoplasms

Functional obstruction (Paralytic ileus)

• Trauma
• Peritonitis
• Heavy concentrate feeding
• Congenital defects – agenesis of colon, visceral eventration

Clinical signs

Incomplete obstruction: Pain in initial stages of obstruction, Cessation of defecation, Anorexia, Distension of abdomen, Looking towards site of pain (colic symptoms), Kicking at the abdomen, Frequent standing and lying down, Increased pulse rate (depend upon duration of obstruction and involvement of blood vessels), Faeces is scanty with blood and thick mucus, Hypovolemia, Endotoxaemia (in strangulated obstruction) cause cardiovascular embed assent and depression.

Diagnosis

History, clinical signs, rectal examination, laboratory findings, complete absence of defecation also seen in diaphragmatic hernia (radiography will help in diagnosis)

Treatment

• General lines- includes Right flank laparotomy Removal of obstruction
• Intraluminal mass– enterotomy
• If intestinal segment is damaged– enterectomy and anastomosis

Caecal dilatation or torsion

Caecal dilatation or torsion of the caecum involves distension, displacement and torsion of the caecum including the spiral colon.

• Free end of caecum in cattle is devoid of mesentery and thus prone to rotation. Dilatation may precede or follow the torsion.
• Condition is more common in dairy cows following parturition
• In buffaloes caecum is not predisposed to torsion because blind end is not devoid of mesentery

Etiology

Main cause of Caecal dilatation or torsion is excessive feeding of grains, this leads to-

• Results in production of increased concentration volatile fatty acids (VFA)
• Gas due to fermentation of undigested grains
• Volatile Fatty acids cause hypo-motility or atony of the caecum resulting in accumulation of gas and ingesta with subsequent dilatation and possible torsion of the organ

Clinical signs

• Simple dilatation takes gradual course
• Onset may be acute if torsion occurs
• Clinical signs– similar to bowel obstruction
• Abdominal pain– early course of disease
• Rapid loss of appetite
• Cessation of defecation
• Dehydration
• Temperature, pulse and respiration rate – normal
• Subnormal temperature, tachycardia – in advanced cases of caecal torsion
• Hypo motility or atony of rumen
• Distended right paralumbar fossa
• Tympanic resonance of right paralumbar fossa on auscultation and percussion
• On rectal palpation – a long cylindrical movable gas filled structure in pelvic inlet or just close to pelvic bone
• Rupture of distended caecum during transportation of animal is a possibility and if it occurs death is sudden

Diagnosis

• History
• Clinical signs
• Auscultation and percussion
• Rectal palpation
• Right flank laparotomy
• biochemistry
• Hypochloremic, hypokalemic, metabolic alkalosis
• Haemo concentration and azotemia – similar in bowel obstruction
• Auscultation and percussion of right flank
• Smaller resonant area and more caudal in case of caecal dilatation (in case of right side displacement of the abomasum – more cranial)

Treatment

• Conservative treatment – when animal is in good condition
• Administration of parasympathomimetic drugs – (Neostigmine)
• Total dose of 12.5 – 2.5 mg s/c for every 3-4 hours for a period of 2-3 days
• A continuous drip of neostigmine (200 mg/10L normal saline)
• Saline purgatives alone or with liquid paraffin

Surgical treatment

Surgical treatment for Caecal dilatation or torsion in animals are-

1. Caecostomy
2. Typhlectomy

Caecostomy

• Right flank laparotomy in standing position
• Exteriorise the free end of caecum
• Milk out the caecal contents following caecostomy
• Clean the caecal edges with normal saline
• Suture with absorbable suture with Cushing pattern followed by Lembert suture pattern
• If torsion is there, correction should be made
• Reposition of the caecum into abdominal cavity
• Laparotomy wound is closed in a routine manner

Typhlectomy

• In cases where the caecum is devitalized and necrotic, resection is indicated
• After exteriorisation of caecum through right flank
• Intestinal clamps on the distal end of the ileum and proximal end of the colon should be placed.
• Blood vessels supplying the caecum should be dorsally ligated and severed
• The necrosed caecum in resected out and cut edges of ileum and colon are anastomosed by using synthetic absorbable suture material
• Close the laparotomy incision in a routine manner
• Partial resection is sufficient if only a part of caecum is necrosed

Post operative care

Administration of broad spectrum antibiotics, adequate fluid therapy. Prognosis is good following surgery.

Twist or rotation of the colon in horses

Symptoms

Intermittent diarrhoea and hypoalbuminemia, depression, anorexia and emaciation are the symptoms of Twist or rotation of the colon in horses.

Diagnosis

• Usual symptoms indicative of twist or stoppage of the bowel are evinced
• Rectal examination. Reveals twist of the colon
• In front of the anus one feels the distended colon
• In torsion towards the right they run backwards and inwards
• In torsion towards the left, backwards and outwards

Prognosis

Prognosis for twist or rotation of the colon in horses is favourable to guarded.

Treatment

Treatment for twist or rotation of the colon in horses is only surgical-

• Explore the abdomen
• Collect the specimen and isolate the involved intestine with laparotomy pads.
• Manually distort the twisted colon
• Evaluate for viability and perforation
• Perform a resection and anastomosis if devitalised

Rectal prolapse

Rectal prolapse is the most common surgical condition involving the rectum in cattle, buffaloes, and small ruminants.

Etiology

• Prolonged tenesmus
• Increased intra abdominal pressure due to bloat
• Rectal inflammation and irritation
• Diarrhoea
• act of parturition
• Straining
• Foreign bodies
• Perineal hernia
• Constipation
• Congenital defects

Classification

Rectal prolapse can be classified in two types-

1. Incomplete rectal prolapse
2. Complete rectal prolapse

Incomplete rectal prolapse

Incomplete rectal prolapse is the prolapse involving only the mucosa of rectum.

Complete rectal prolapse

Complete rectal prolapse is the prolapse of whole thickness rectal wall. Constriction due to tight anal sphincter leads to extensive necrosis of prolapsed tissue.

Diagnosis

Visual observation of mass of varied length protruding from the anus is the base of diagnosis.

Treatment

• Reduction after lavage with a astringent solution and application of an emolient
• Purse string suture in the skin around anus by leaving an opening which permits defecation
• To abolish straining– epidural anaesthesia
• Animals should be kept on laxative diet for few days to prevent constipation
• Recurrence is common in this method
• Initiating cause must be treated to effect cure

Post surgical management

Regular cleaning, dressing with topical anaesthetic and use of systemic antibiotics in rectal prolapse.

Congenital malformation of large intestine

Congenital malformation of large intestine is common in all animals.

The anorectal passage is developed from two distinct centres in the embryo. Normally the two tubes coalesce to form a single conduit. Sometimes one of the parts or both is insufficiently developed.

The following anomalies may be met with-

1. Neither rectum nor the anus is fully formed– atresia ani et recti , atresia ani et coli
2. Rectum is fully developed but anus is absent– imperforate anus

Rectum and bladder as one cavity-

1. 
    Recto vesicular fistula
2. 
    Recto urethral fistula
3. 
    Recto vaginal fistula

As development proceeds it divides into two compartments, the lower one forming the bladder and urethra. If the separation is incomplete, recto vaginal or a recto urethral fistula results.

Symptoms

In case of complete obstruction-

• With in few hours after birth
• Abdominal pain
• Distended abdomen
• Straining without expulsion of meconium

Tumors of Rectum

Warts, cysts, lipomata, myxomata, sarcomata, adenomata and carcinomata are the tumors of Rectum in animals.

Cysts, polypoid myxomata and fibromata are the most common tumors of the rectal mucous membrane.

Symptoms

• Severity of the symptoms vary according to the size of the tumour
• Difficulty in defecation
• In case of ulcerated tumor– blood and pus may be seen in faeces
• Signs of colic
• Tumor inside the rectum may protrude through the anus during defecation

Diagnosis

• Deformity of rectum due to new growth
• Rectal examination

Prognosis

• Benign tumors are easy to remove
• Malignant tumors are incurable

Treatment

• Polypoid growth may removed by ecraseur or by ligation
• Cysts corrected by needle aspiration and use of irritants like tincture iodine
• Radical surgery for excision of tumor

Paralysis of Rectum

Paralysis of Rectum is most common in the horse and dog; Rare in ruminants.

Paralysis of Rectum is frequently associated with paralysis of the tail, or the bladder and hind limbs.

Etiology

• Lesions of the spinal cord or nerves supplying the rectum
• Fractures and severe injuries of the sacrum, tumours of the sacral region
• Toxins of infectious diseases such as strangles
• Old age
• Paralysis may be complete or incomplete

Symptoms

• Distended rectal walls
• Accumulation of faeces
• Inability of the animal to expel faeces
• Colic symptoms
• The tail is limp and powerless
• Anus is open

Prognosis

Prognosis is usually unfavourable in case of paralysis of rectum.

Treatment

Treatment is in case of paralysis of rectum is nerve tonics and supportive care as prognosis is unfavourable.

Rectal tear

Rectal tear is primarily due to trauma and it rarely reported in ruminants.

Classification

Rectal tear can be classified in four grades-

1. Grade 1: Tears involves mucosa or mucosa and submucosa
2. Grade 2: When only muscular layer gets ruptured
3. Grade 3: Involves mucosa, sub mucosa and muscular layer
4. Grade 4: Penetrates all layers and enters peritoneal cavity

Diagnosis

• Presence of excessive amounts of blood on glove on rectal palpation
• Easily palpable viscera
• Signs of shock and peritonitis

Treatment

• Under epidural anaesthesia the distal rectal tear is corrected using an absorbable suture material using inversion pattern.
• In case of proximal rectal tears– right flank laparotomy has t be performed to repair the rectal tears

Colic in horses

Colic is defined as visceral abdominal pain due to spasmodic colic contraction and is presented as acute, chronic or recurrent.

Etiology

• Diet
  • Coarse roughage- impaction colic due to low digestibility
  • Grain overload- Colic and laminitis due to increased gas production leading to altered mobility and displacement of the bowel
• Environmental factor- Extreme summer or winter and confinement without exercise
• Parasites- ascarides, tapeworm, strongyles
• Cribbing results in aerophagia and negative pressure created will result in movement of the bowel in to potential space within the lesser omental sac and entrapment of intestine in to the epiploic foramen
• Pregnancy (Compression of the bowel by gravid uterus and After delivery the space occupied by the uterus will be filled with intestine.)

Types of colic

Types of colic are-

1. Pelvic flexure impaction
2. Spasmodic colic
3. Ileal impaction
4. Sand impaction
5. Enterolith
6. Large round or tape worms
7. Left dorsal displacement
8. Epiploic foramen entrapment
9. Mesenteric rent entrapment

Pathology

Pathology of colic in horses can be divided in to-

• Simple obstruction,
• Strangulating obstruction
• Non-strangulating obstruction

Treatment

Treatment of colic in horses focus on pain management and surgical management-

Pain management

• Nasogastric intubation
• Decompression(enterocentesis)
• Flunixin meglumine
• Alpha 2 agonists, Xylazine and detomidine o opioids
• Spasmolytic agents
• Lidocaine as a prokinetic drug

Surgical management

Under general anesthesia and dorsal recumbency through a midline laparotomy the correction is performed on the intesines and the abdominal incision is closed. Rough recovery from anesthesia is to be avoided.