Intussusception in dogs: symptoms, surgery and recovery

Overview

Normally, waves of intestinal contractions move contents forwards. In intussusception, the section sliding inside another narrows the passage for food and fluid. Obstruction may be partial or complete.

Common sites are the small intestine or the junction between the small and large intestines. Usually, an upstream section slides into a downstream section in the normal direction of passage. However, intussusception can also develop in the opposite direction. In some dogs it resolves spontaneously at times and then returns. Temporary improvement therefore does not exclude intussusception.

In a group of 153 surgically treated dogs, the most common individual site was the junction between the small and large intestines, affected in 66 dogs, or 43%.

Causes

Uneven intestinal movement encourages telescoping

Intussusception may result from an imbalance in intestinal movement caused by inflammation or another disease. A strongly moving section can slide inside an adjacent, poorly moving section. In dogs, this can occur during severe illness with vomiting and diarrhoea.

Parasites and bacterial or viral intestinal inflammation can predispose dogs to intussusception. Parvovirus is one possible inflammatory trigger. A foreign body can alter intestinal function and act as a starting point. A tumour or chronic inflammatory intestinal disease can also underlie it.

A thread-like foreign body can gather up the intestine and contribute to intussusception. However, the precise cause cannot always be established. A dog may have more than one intussusception.

Compression can damage the intestinal wall

Blood vessels in the telescoped intestine may be compressed, causing swelling. Prolonged disruption of blood flow can lead to tissue death. Damaged intestine may leak contents into the abdomen. This can cause life-threatening inflammation of the abdominal lining, called peritonitis.

Risk factors

Intussusception is most common in dogs under 1 year old, although adults can also be affected. Among 153 dogs requiring surgery, median age was 10 months, ranging from 2–156 months. Parasites, intestinal infections and swallowing foreign bodies are important predisposing factors in young dogs.

In older dogs, possible intestinal tumours or intestinal wall disease are investigated carefully. German Shepherd Dogs have been described as more predisposed than other breeds. Previous abdominal or intestinal surgery may be associated with intussusception. In the same group of 153 dogs, 19% had undergone surgery within the previous 30 days.

Typical symptoms

Vomiting or diarrhoea may start before the intussusception itself develops. Severity depends on the location and whether obstruction is complete.

• Your dog vomits or cannot keep food and water down.
• Stools are loose or contain fresh blood.
• Appetite decreases or your dog refuses food.
• Your dog seems subdued, tired or depressed.
• The abdomen is tender, tense or swollen.
• Prolonged illness may cause weight loss.

Stools may initially be normal or loose even with obstruction. With prolonged complete obstruction, your dog may stop passing stools. Mild or intermittent intussusception can cause problems for weeks or months.

With intussusception at the small–large intestinal junction, intestinal tissue may sometimes protrude from the anus. Your vet distinguishes this from a true rectal prolapse by examining the tissue and surrounding area.

Complications and consequences

Intestinal damage and surgical join leakage are serious risks

Complete intestinal obstruction can cause dehydration and electrolyte and acid–base disturbances. Damaged intestine can perforate and cause bacterial peritonitis. Sepsis and shock are also possible complications.

If a large amount of intestine must be removed, the remaining section may be insufficient for normal nutrient absorption. Breakdown of the intestinal join after surgery can cause another life-threatening episode of peritonitis. Leakage most commonly appears around 3–5 days after surgery. A seriously unwell dog may have poorer tissue healing.

Low preoperative albumin, below 2–2.5 grams per decilitre, is associated with an increased risk of intestinal join breakdown. Glucocorticoid treatment can also increase this risk. Leakage generally requires another operation and carries a high risk of death.

Severe illness can also involve a widespread clotting disorder. After surgery, diarrhoea and regurgitation, the return of food, can complicate recovery. The outlook depends on obstruction duration, location and extent, and the associated intestinal damage.

The outlook is often good, but recurrence is possible

Early surgery and effective supportive care improve survival chances. Of 153 surgically treated dogs, 144, or 94.1%, survived the first 14 days after surgery. Serious or life-threatening surgical complications occurred in around 14%.

Recurrence rates of 11–20% after surgery have been described. Rates in smaller patient groups have also ranged from 6–27%. In a separate group of 153 dogs, intussusception recurred in 4, or around 3%. All these recurrences were identified within 72 hours of surgery. Later recurrence is also possible, even 3 weeks after the procedure.

Diagnosis at the vet

Examination and laboratory tests also assess general condition

Your vet asks when signs began and how vomiting and diarrhoea progressed. Abdominal palpation may reveal a sausage-shaped, thickened intestinal section. Examination also assesses dehydration, pulse and mucous membrane colour. These changes in general condition are not specific to intussusception.

A blood count, biochemical blood tests and urinalysis are usual basic investigations. Results are assessed for dehydration, electrolyte disturbances and possible kidney injury. Faecal testing can look for intestinal parasites as a possible underlying cause.

With intestinal perforation, white blood cells may be increased or reduced because of severe inflammation. Vomiting and obstruction can also change blood potassium, chloride and acid–base results. Obstruction patients often have increased lactate or concentrated blood, called haemoconcentration.

Ultrasound shows concentric intestinal layers

On plain X-rays, complete obstruction may appear as bowel loops dilated with gas and fluid. Partial obstruction may remain unclear on plain X-rays. Ultrasound often shows intussusception as concentric rings resembling a target. In a lengthways view, intestinal wall layers appear nested inside one another.

Ultrasound can also help identify the underlying disease. Sometimes a contrast study or CT is needed. If perforation is suspected, a water-soluble iodine contrast agent is chosen instead of barium. Exploratory abdominal surgery can both diagnose and treat intussusception.

Tissue samples may reveal an underlying disease

Intestinal tissue samples can investigate underlying inflammation or a tumour. Samples were examined from 93 dogs, or 60.8%, in the same surgical group.

Treatment

Fluids are corrected and intestinal viability assessed

Treatment begins by supporting circulation and correcting dehydration with intravenous fluids. Electrolyte abnormalities identified in blood tests guide fluid selection. Surgery takes place as soon as your dog can tolerate anaesthesia and the procedure. Medication and surgery are managed by your vet.

The surgeon examines the abdomen for an underlying cause and other intussusceptions. If the intestine is sufficiently healthy, the intussusception can sometimes be gently reduced by hand during surgery. Dead tissue or a section that cannot be reduced is removed. Healthy ends are joined with sutures or staples, creating an anastomosis. In the group of 153 surgical patients, intestinal removal and joining were needed in 129 dogs, or 84%.

Attempts to reduce intussusception can also damage the intestine during surgery. Such injuries occurred in 10 of the 153 dogs, or around 7%.

The benefits and harms of fixing intestinal loops together are weighed individually

Enteroplication involves fixing intestinal loops to one another to prevent recurrence. It has not been shown to reduce recurrence statistically significantly compared with treatment without fixation. However, results in small patient groups have tended to favour fixation.

Fixation can also predispose dogs to another intestinal obstruction. Rarely, an intestinal section can become strangulated between the fixation sutures. The choice depends on individually weighing recurrence risk against procedural harms.

Recovery needs pain relief and early nutrition

Pain after surgery is often treated with opioid painkillers. Intravenous fluids continue if needed until your dog eats normally. Antibiotic need depends partly on contamination of the abdomen or surgical site. Underlying parasites or intestinal disease are also treated.

Most patients can receive food within 24 hours of surgery. In the 153-dog group, median hospitalisation was 2 days, ranging from 1–14 days. Exercise is restricted to quiet lead walks for around 10–14 days, avoiding running and jumping. Persistent vomiting after surgery may be associated with loss of intestinal movement.

Prevention

Identifying and treating the cause of intestinal inflammation is central to preventing recurrence. Parasitic inflammation needs antiparasitic treatment. A dietary change also forms part of ongoing care for some dogs. Preventing swallowed foreign bodies reduces one recognised predisposing factor. Abrupt dietary changes can contribute to intestinal inflammation and intussusception.

If an intestinal wall tumour or chronic inflammation underlies the problem, treating it remains part of care after relieving the obstruction. A preventable cause cannot be found in every case.

Important for dog owners

Record when vomiting or diarrhoea began and whether there were clearly better periods between episodes. Tell your vet about previous abdominal surgery, parasites and possible swallowing of a foreign body.

New vomiting or abdominal pain during recovery requires contact with the treating practice, because intussusception can recur.

Bring previous test results and discharge instructions. Before discharge, agree how feeding and follow-up will be managed. At home, record eating, vomiting, bowel movements and energy levels. Also note how well the prescribed exercise restriction has been maintained.

Frequently asked questions

Can a dog pass stools with intussusception?

Early in intestinal obstruction, your dog may still pass stools, which can be normal or diarrhoeic. With prolonged complete obstruction, bowel movements may stop. Passing stools alone therefore does not exclude obstruction if your dog is vomiting and deteriorating.

Does intussusception always need surgery?

Most intussusceptions require surgery. Occasionally one reduces spontaneously, but it can develop again. Surgery assesses intestinal viability and removes the damaged section if necessary. Waiting at home is unsuitable for a dog with severe signs, because obstruction can rapidly cause intestinal tissue death.

Why is intussusception more common in puppies?

Intestinal parasites, viral intestinal inflammation and swallowing foreign bodies in young dogs can disrupt intestinal movement. Intussusception is most common in dogs under 1 year old. Adults can also be affected, with particular attention during investigation to possible intestinal tumours or wall disease.

Can intussusception return after successful surgery?

Intussusception can recur, with postoperative recurrence rates of 11–20% described. In a group of 153 dogs, recurrence occurred in 4, or around 3%. All these recurrences happened within 72 hours. Renewed vomiting and abdominal pain warrant reassessment.

How long does recovery from intussusception surgery take?

In a group of 153 dogs, median postoperative hospitalisation was 2 days, but ranged from 1–14 days. Exercise is generally restricted for 10–14 days. Recovery depends partly on how much intestine was removed and the damage caused by obstruction. The risk of intestinal join leakage is greatest around days 3–5.