Page 423 - Small Animal Internal Medicine, 6th Edition

CHAPTER 26 Clinical Manifestations of Gastrointestinal Disorders 395

Vomiting
VetBooks.ir History/physical examination

Acute Chronic Hematemesis

Animal not very ill Tentative acute Animal very ill See Fig. 26.3
gastroenteritis or suspect serious
disease

Minimal diagnostics
Symptomatic/Supportive therapy

If not responsive to CBC/chemistry profile/urinalysis (thyroxine, FeLV, and FIV in
appropriate therapy... cats), (cPLI and serum cortisol in dogs), plain abdominal
radiography and/or ultrasonography, supportive therapy

If not diagnostic, then fasting/post-prandial serum bile acid
concentrations serum gastrin concentration

Gastroduodenoscopy and biopsy ( colonoileoscopy in cats)

If no diagnosis, then consider CSF tap, CT, MRI

FIG 26.2
General diagnostic approach to vomiting in the dog and cat. CBC, Complete blood
count; cPLI, canine pancreatic lipase immunoreactivity; CSF, cerebrospinal fluid; FeLV,
feline leukemia virus; FIV, feline immunodeficiency virus; MRI, magnetic resonance imaging.

guessing wrong, if the vomiting persists for 2 to 4 days after aggressive diagnostic testing is appropriate. Animals with
the start of symptomatic therapy, or if the condition worsens acute or chronic vomiting without hematemesis should
during this initial time, then more aggressive diagnostic undergo abdominal radiography and/or ultrasonography
testing is usually appropriate. to look for intestinal obstruction, foreign objects, masses,
The clinician should search for historical evidence of pancreatitis, peritonitis, poor serosal contrast, alimentary
ingested foreign objects, toxins, inappropriate food, or drugs. tract ileus, free abdominal fluid, or free abdominal gas.
Physical examination is used to look for abdominal abnor- Abdominal ultrasonography can be more revealing than
malities (e.g., masses, pain) and evidence of extraabdominal plain radiographs, but radiographs may be more sensitive
disease (e.g., uremic glossitis, a thyroid nodule indicative of in revealing free air and some foreign bodies. A CBC, serum
hyperthyroidism). Clinicians should always look for linear biochemistry profile, and urinalysis are also indicated. Cats
foreign bodies in vomiting cats and carefully examine the should be tested for feline leukemia virus, feline immunode-
base of the tongue; chemical restraint (e.g., ketamine HCl, ficiency virus, and hyperthyroidism. It may be necessary to
2.2 mg/kg of body weight given intravenously) may be nec- measure serum bile acid concentrations (or blood ammonia
essary to examine this area properly. The abdomen is pal- concentrations) or resting serum cortisol concentrations to
pated to search for masses or pain, but even careful palpation screen for hepatic or adrenal insufficiency, respectively, that
may miss short ileocolic intussusceptions in the craniodorsal can be unsuspected based on serum biochemistry profiles.
abdomen. It is reasonable to perform fecal examination for Immunoreactive pancreatic lipase activity can be helpful in
parasites because they can cause vomiting. If a cause cannot diagnosing otherwise occult canine pancreatitis, but it must
be found and the animal is not unduly ill, the clinician may be remembered that the test cannot be used as a simple
prescribe a therapeutic trial (e.g., pyrantel and a dietary trial; litmus test for clinically important pancreatitis.
see Table 28.7). Therapeutic trials should be designed so that If results of extensive clinical pathology testing and ab-
failure of the therapy allows the clinician to exclude at least dominal imaging are not diagnostic in a patient with chronic
one disease. vomiting, the next diagnostic step is usually upper GI endos-
If acute vomiting does not respond to symptomatic copy. If endoscopy is not available, then exploratory laparot-
therapy or if the animal is so sick that the clinician cannot omy may be substituted, but surgery can miss gastric lesions
take a chance on symptomatic therapy being ineffective, that will be picked up endoscopically. Contrast gastrograms