Background
Pancreatitis is an elusive disease in cats and consequently has
been underdiagnosed. This is owing to several factors. Cats with
pancreatitis present with vague signs of illness, including lethargy,
decreased appetite, dehydration, and weight loss. Physical
examination and routine laboratory findings are nonspecific, and
until recently, there have been limited diagnostic tools available
to the practitioner for noninvasively diagnosing pancreatitis. As a
consequence of the difficulty in diagnosing the disease, therapy
options are not well understood.
Now available, the SNAP
®
fPL™ and Spec fPL
®
tests can help rule
in or rule out pancreatitis in cats presenting with nonspecific signs
of illness. As our understanding of this disease improves, new
specific treatment modalities may emerge. For now, the focus is
on managing cats with this disease, and we now have the tools
available to more critically evaluate these cases.
Placebo-controlled studies in people have revealed that the only
treatment strategies proven effective for pancreatitis are fluid
therapy, pain management, and nutritional support. These are
also the mainstay of therapy for treating cats with pancreatitis.
Studies have shown, however, that approximately
2
/3 of cats
with pancreatitis have chronic disease for which treatment
recommendations are less clear.
1,2
In addition, many cats are
affected by concurrent illnesses (e.g., diabetes mellitus, hepatic
lipidosis, cholangitis, and inflammatory bowel disease).
3 – 5
Diagnosis and management of both pancreatitis and concurrent
conditions are critical to a successful outcome.
6
Fluid therapy
Intravenous fluid therapy is key to supporting a patient with
pancreatitis. The main goal is to ensure that the pancreas is being
adequately perfused. Initially, fluids should correct dehydration
over the first 12–24 hours while also meeting maintenance needs
and replacing ongoing losses of fluids from vomiting, diarrhea,
and third-space losses (e.g., peritoneal effusions secondary to
pancreatitis). Acid-base and electrolyte abnormalities should be
monitored closely and corrected. If hypocalcemia is noted in a cat
with acute necrotizing pancreatitis, calcium gluconate should be
given at doses of 50–150 mg/kg intravenously over 12–24 hours
and serum total or ionized calcium concentrations should be
monitored during therapy. Colloids, such as dextran or hetastarch,
can be used to support oncotic pressure, especially in patients
that are hypoalbuminemic. Plasma therapy, although not as readily
available for cats as it is for dogs, can be used if there is evidence
of coagulopathy or disseminated intravascular coagulation (DIC).
Pain management
Abdominal pain is frequently recognized in dogs with pancreatitis;
however, it is rarely recognized in cats. Nonetheless, many cats
will show clinical improvement if provided analgesic therapy.
Because of this, many experts agree that pain management should
be provided in all cats with acute pancreatitis. Opioid therapy
is recommended. Fentanyl transdermal patches have become
popular for pain relief because they provide a longer duration of
analgesia. It takes at least 6 hours to achieve adequate fentanyl
levels for pain control; therefore, one recommended protocol is to
administer another analgesic, such as intravenous buprenorphine,
at the time the fentanyl patch is placed. The cat is then monitored
closely to see if additional pain medication is required. Cats with
chronic pancreatitis may also benefit from pain management, and
options for outpatient treatment include a fentanyl patch, sublingual
buprenorphine, oral butorphanol, or tramadol.
Antiemetic therapy
Vomiting, a hallmark of pancreatitis in dogs, may be absent or
intermittent in cats. When present, vomiting should be controlled;
and if absent, treatment with an antiemetic should still be
considered to treat nausea. There are several antiemetics available.
Metoclopramide (Reglan
®
) is a popular antiemetic in cats and is
still used by many practitioners. However, metoclopramide is a
dopamine antagonist and inhibits vomiting by blocking the central
nervous system (CNS) dopamine receptors in the chemoreceptor
trigger zone (CRTZ). It is probably not a very good antiemetic
in cats because they are reported to have few CNS dopamine
receptors in the CRTZ. Dolasetron (Anzemet
®
) and ondansetron
(Zofran
®
) act on the serotonin 5-HT
3
receptors in the CRTZ and are
very effective in cats. Lastly, although maropitant citrate (Cerenia
®
)
is only labeled for use in dogs, it has become a popular and
effective antiemetic for use in cats and acts on the neurokinin (NK)
receptors in the vomiting center and can be used at
1
/2 of
the dog dose.
Nutritional support
Experts recommend enteral nutritional support in all patients
with pancreatitis. The historical recommendation of nothing per
os (NPO) for animals with pancreatitis is no longer accepted.
In addition, cats can develop hepatic lipidosis if not provided
adequate calories. The new dogma has become this: if the
gastrointestinal tract works, use it; and if the patient is vomiting,
give an antiemetic so that they keep the food down. Enteral
nutrition stabilizes the gastrointestinal barrier, improves enterocyte
health and immune function, improves gastrointestinal motility,
prevents catabolism, and decreases morbidity and mortality.
Cats with pancreatitis are inappetant; therefore, ingestion of
adequate calories is rare. Force feeding is not recommended
because it is difficult to achieve the appropriate level of caloric
intake, and force feeding can also lead to food aversion.
7
Enteral
nutrition can be provided by a variety of feeding tubes, including
nasogastric, nasoesophageal, esophagostomy, gastrostomy, or
jejunostomy tubes.
If vomiting cannot be controlled, then partial parenteral nutrition
(PPN) or total parenteral nutrition (TPN) can be provided to meet
some or all of the patient’s caloric needs. TPN is typically only
available in 24-hour care facilities, but PPN is more user-friendly
and practical for use in any practice. However, although parenteral
Treatment recommendations
for feline pancreatitis