Contributors: Steven Marks, Elisa Mazzaferro, Zoe Halfacree

 Species: Canine   |   Classification: Diseases

Introduction Pathogenesis Diagnosis Treatment Outcomes Further Reading


  • Acute onset of abdominal pain.
  • Prompt diagnosis and immediate medical or surgical intervention necessary to prevent deterioration of patient.

Presenting Signs

  • Abdominal pain/abdominal splinting.
  • Sometimes abdominal distension.
  • Vomiting.
  • Diarrhea.
  • Postural changes.
  • Gait changes: stiff stilted gait.
  • Anorexia.
  • Lethargy.
  • Shock.

Age Predisposition

Breed Predisposition



  • Depends on primary cause.
  • Sources of abdominal pain include the following systems:
    • Urogenital.
    • Gastrointestinal.
    • Splenic.
    • Hepatobiliary.
    • Pancreatic.
    • Peritoneal.
  • Displacement, obstruction or distention, inflammation or infection, perforation or rupture, and/or vascular compromise in any of these systems can result in somatic or visceral pain and the presentation of an acute abdomen.


  • Abdominal pain caused by distention/stretch, inflammation or ischemia of solid or hollow abdominal organs, mesentery or parietal peritoneum.
  • Ischemia and inflammation can also result in activation of pain receptors via the release of mediators such as bradykinin, serotonin, histamine and eicosanoids.


  • Acute onset.


Presenting Problems

  • Ask yourself the following immediate questions:
    • Does the patient require IMMEDIATE resuscitation?
    • Does the patient require invasive cardiorespiratory monitoring?
    • Are diagnostic tests necessary?
    • Does the patient require urgent surgery?
    • Does the patient require a surgical work-up?

Client History

  • Ask client specific questions:
    • Toxin exposure? (ethylene glycol, other).
    • Garbage ingestion or dietary indiscretion (deliberate or accidental)?
    • Foreign body exposure?
    • Possibility of trauma?
    • Nature and character of vomit? In relation to meals/eating?
    • Vaccination status Canine parvovirus.
    • Health status of other animals or humans in household?
    • Type, dose and duration of any drugs (NSAID Analgesia: NSAID , steroids)?
    • Recent heat cycle in unspayed female dogs?

Clinical Signs

Physical examination

  • Perform a thorough physical examination.
    Perform abdominal examination LAST, as it can be painful and may lead you to miss vital clinical signs.


  • Eyes: sunken, anisocoria (trauma or toxin), mentation, seizures (metabolic or toxin).
  • Tongue: look carefully under the tongue for the presence of string/linear foreign bodies (uncommonly lodged here in dogs).
  • Fur around muzzle:
    • Look for evidence of excessive salivation (nausea).
    • Look at fur around muzzle for evidence of vomit or toxin (Wood's lamp used to detect ethylene glycol Ethylene glycol poisoning. Ethylene glycol may fluoresce under a black light/Wood's lamp Woods lamp ).
  • Mucous membranes:
    • Color.
    • Tachyness.
    • Capillary refill time.
    • Rapid CRT with endotoxin/sepsis.
    • Prolonged CRT with hypovolemic shock.

Thoracic auscultation

  • Lungs Respiratory: disease - clinical investigation:
    • Normal or harsh/crackles (aspiration pneumonitis secondary to vomiting?).
    • Respiratory rate and effort.
  • Cardiac Heart: disease - clinical investigation:
    • Murmurs?
    • Arrhythmias? (severe bradycardia if hyperkalemia and atrial standstill present with urinary tract obstruction or rupture).
    • Pulse quality and character/synchrony.
    • Bounding pulses with endotoxic/septic shock.
    • Poor pulse quality with hypovolemic shock.

Orthopedic and neurological examination

  • In stable patients, perform complete neurological examination Neurological examination:
    • Cranial nerves: decreased function (botulism Botulism ).
    • Gait abnormalities: botulism, spinal pain due to intervertebral disk disease can be mistaken for abdominal pain.
    • Mentation: dull depressed with shock, trauma, seizures, toxins.
  • Patients with abdominal pain can present with a stiff stilted gait and have gait abnormalities ("walking on eggshells").
Spinal pain can be mistaken for abdominal pain, so thorough physical examination is essential.


  • Look carefully for evidence of penetrating trauma, blood on haircoat.
  • Look carefully for evidence of bruising or hemorrhage.
  • Look carefully at skin around umbilicus for discoloration.
    May appear red in color with intra-abdominal hemorrhage.
  • Look at feet and prepuce/vulva for ethylene glycol with Wood's Lamp Woods lamp.

Abdominal examination

Always perform last as it may be painful and distract your attention from other important systems.
  • Abdominal examination consists of 4 parts:
    • Visual inspection.
    • Auscultation.
    • Percussion.
    • Palpation.

Visual inspection

  • Distention (hemoabdomen, mass effect, distended viscus like GDV).
  • Deformity (mass effect, GDV).
  • Bruising on skin.
  • Discoloration around umbilicus (indicative of intrabdominal hemorrhage).
  • Penetrating wounds.


  • Increased borborygmi if acute obstruction, gastroenteritis, toxin.
  • Decreased borborygmi if chronic obstruction, anorexia, peritonitis Peritonitis , ileus.


  • Hyperresonant with intraabdominal air.
  • Hyporesonant if intraabdominal fluid.


  • Masses.
  • Organomegaly Abdominal organomegaly.
  • Plication of intestines (linear foreign body Intestine: linear foreign bodies ).
  • Fluid.
  • Distention.
  • Pain? Localized versus generalized?
  • Rectal examination (always look at both ends). Feel for:
    • Masses.
    • Sublumbar lymph nodes.
    • Pelvic urethra.
    • Feces.
    • Hematochezia.
    • Melena.
    • Prostate.
      Approximately 50% of physical examinations will have negative results!

Diagnostic Investigation

First wave diagnostics

BUN Blood biochemistry: urea


Electrolytes/acid base

Complete blood count

Serum biochemistry profile

  • Non-specific changes according to affected systems.



  • Elevated ACT, APTT, PT with suspect DIC Disseminated intravascular coagulation.
  • Thrombocytopenia with DIC.
  • Elevated fibrin degradation products with DIC.
  • Hepatic disease, neoplasia, vasculitis.

Urinalysis Urinalysis

  • Renal tubular casts, acute renal failure.
  • Calcium oxalate monohydrate crystals (ethylene glycol).
  • WBC's, bacteriuria, pyelonephritis Kidney: pyelonephritis , cystitis Cystitis.

Abdominal radiographs Radiography: abdomen or computed tomography Computed tomography

  • Loss of detail in abdomen:
    • Peritonitis Abdomen peritonitis - radiograph lateral.
    • Lack of intrabdominal fat.
    • Hemoabdomen.
    • Ascites .
  • Free gas:
    • Ruptured viscus.
    • Penetrating wound.

Always perform abdominal radiographs before performing abdominocentesis, as iatrogenic pneumoperitoneum can occur during procedure.

Abdominal ultrasound/AFAST scan (Abdominal focused assessment using sonography for trauma Triage)
  • Free fluid Abdomen pancreatitis - ultrasound.
  • Masses.
  • Architecture and size of abdominal organs.
  • Ultrasound-guided abdominocentesis.

Abdominocentesis Abdominocentesis Effusion: overview

  • Indications:
    • Loss of serosal detail on abdominal radiographs.
    • Penetrating injury, where penetration reaching the peritoneal cavity is unclear.
    • Persistent abdominal pain of unknown cause.
    • Post-operative complications following abdominal surgery.
    • Perform four quadrant abdominocentesis or ultrasound-guided abdominocentesis.

Diagnostic peritoneal lavage (DPL) Abdominal lavage Investigation of Acute Abdomen

  • Indicated when peritonitis or other effusive disease is suspected but other techniques have failed to provide a diagnostic sample.

Fluid analysis Peritoneal fluid: bile Peritoneal fluid: urine Peritoneal fluid hemorrhagic Peritoneal fluid serosanguinous


Initial Symptomatic Treatment

  • Stabilize shock Shock: septic Shock.
  • Intravenous crystalloid fluids Fluid therapy , colloids, and blood products Blood: transfusion , as appropriate.
  • Shock can be septic in origin or secondary to hypovolemia.
  • Hypovolemic shock caused by:
    • Blood loss.
    • Third spacing.
    • Sepsis/endotoxin.
    • Vomiting/diarrhea.
    • GDV/mesenteric torsion.
  • Oxygen.
  • Broad spectrum antibiotics Therapeutics: antimicrobial drug. Gram positive, gram negative and anaerobic activity.
  • Analgesics after initial assessment Analgesia: overview.
  • Patient has presented due to abdominal pain. Some practitioners believe that giving analgesics may mask ongoing signs. However, appropriate diagnostics must be performed to further evaluate patient. Ongoing pain can decrease response to shock therapy, therefore, analgesics are absolutely necessary for treatment following initial assessment.


  • Perfusion parameters:
    • Heart rate.
    • Capillary refill time.
    • Blood pressure.
    • Central venous pressure.
    • Mucous membrane color.
    • Urine output.

Subsequent Management


  • Indications for Surgery:
    • Uncontrollable hemorrhage and inability to stabilize patient.
    • Free gas on plain abdominal radiographs.
    • GDV/mesenteric volvulus Stomach: gastric dilatation / volvulus (GDV) syndrome.
    • Intracellular bacteria, fecal or vegetable/fiber material on DPL.
    • Greater than 2000 cells/mm3 on DPL.
    • Predominantly toxic neutrophils on DPL.
    • Bilirubin in abdominal fluid or green abdominal fluid.
    • Complete bowel obstruction or linear foreign body.
    • Penetrating trauma/foreign body.
    • Splenic torsion.
    • Gunshot wound to abdomen.
    • Evisceration.
    • Abdominal impalement.


Further Reading


Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Walters J M (2003) Abdominal paracentesis and diagnostic peritoneal lavage. Clin Tech Small Anim Pract 18 (1), 32-38 PubMed.
  • Walters P C (2000) Approach to the acute abdomen. Clin Tech Small Anim Pract 15 (2), 63-69 PubMed.
  • Macintire D K (1988) The acute abdomen - differential diagnosis and management. Semin in Vet Med Surg (Small Anim) 3 (4), 302-310 PubMed.

Other sources of information

  • Boag A & Huges D (2008) Emergency management of the acute abdomen in dogs and cats. 1. Investigation and stabilisation. In Practice 26, 9.
  • Mann F A (2000) Acute Abdomen: Evaluation an Emergency Treatment. Current Veterinary Therapy XIII. Ed J D Bonagura. WB Saunders Company, Philadelphia. pp160-164.
  • Holt D & Brown D (1999) Acute abdomen and gastrointestinal emergencies. In: Manual of Canine and Feline Emergency and Critical Care. Eds L G King and R Hammond R. British Small Animal Veterinary Association, United Kingdom. pp. 127-144.
  • Kleine L J (1997) Radiology of acute abdominal disorders of the dog and cat (Parts I and II). In: Emergency Medicine in Small Animal Practice: The Compendium Collection.Veterinary Learning Systems, Trenton, NJ. pp. 336-351.


Other Sources of Information