Page 456 - Clinical Small Animal Internal Medicine

424 Section 5 Critical Care Medicine

serum creatinine (within the reference range) can indi- from perforation of an infected biliary tree, most fre-
VetBooks.ir cate renal impairment and emerging multiorgan failure. quently the gallbladder. Less frequently, infection or
abscessation of organs such as the liver or spleen, or
The central nervous system manifestations of sepsis
and septic shock may be due to the effects of systemic
the source. Spontaneous septic peritonitis can occur in
hypotension and decreased cerebral perfusion or may be necrotic tissue secondary to strangulation or torsion is
related to the direct effects of sepsis‐induced cytokines. cats with no evidence of gastrointestinal compromise or
Alterations in cerebral blood flow, increased capillary other identifiable source.
leakage, and disruption of the blood–brain barrier are Numerous other diseases are capable of causing sepsis
thought to be mechanisms contributing to brain dys- in dogs and cats. Penetrating trauma from animal bites is
function in sepsis. In addition to primary intracranial a common occurrence and contamination from bite
causes, sepsis‐induced hypoglycemia can cause neuro- wounds can result in sepsis. Blunt trauma without pen-
logic dysfunction. The clinical signs seen with sepsis and etrating injury (e.g., being struck by a vehicle or falling
septic shock are predominantly alterations in mentation from a height) frequently results in significant soft tissue
(i.e., obtundation, stupor, coma) and seizures. injury that can result in sepsis if infection of the damaged
tissue occurs.
Epidemiology
Signalment
The exact incidence of sepsis in veterinary medicine is
unknown. However, sepsis is likely a common occur- All species, breeds, sexes, and ages can develop sepsis.
rence in clinical practice and remains among the most Consequently, there is no signalment specific to sepsis
difficult to treat conditions. According to the NIH, about but there are populations that are susceptible to dis-
750 000 people become septic in the United States each eases that can be the underlying cause of sepsis. For
year with a mortality rate of 28–50%. In fact, the rates of example, young, unvaccinated puppies are at risk of
hospitalization for human sepsis have become higher contracting Parvoenteritis while intact female dogs
than those of myocardial infarctions. The death rate and cats may develop pyometra. Dogs that develop
from sepsis eclipses that of prostate cancer, breast can- septic peritonitis tend to be younger with indiscrimi-
cer, and AIDS combined. nate eating habits that ingest foreign material, result-
Despite the difficulty in diagnosing sepsis, there are ing in perforation of the GI tract. A report including
common veterinary diseases that can cause a patient to nearly 75 000 dogs identified some distinct breed‐ and
develop sepsis. Parvoviral enteritis, pyometra, pneumo- age‐related differences in all‐cause mortality, with
nia, and septic peritonitis are just a few of the diseases younger patients having a significantly higher likeli-
responsible for sepsis and septic shock in dogs and cats. hood of dying of infectious disease or trauma. Geriatric
Septic peritonitis occurs in both cats and dogs and dogs with chronic, progressive diseases necessitating
most commonly results from perforation of the GI tract. treatment with NSAIDs, corticosteroids, or other immu-
Because of the propensity of dogs to ingest foreign nosuppressive medications are also at higher risk than
objects, septic peritonitis occurs more commonly in that the general population for developing GI tract perfora-
species. Most frequently, perforation of the GI tract tion. Ruptured neoplasia of the GI tract occurs in both
occurs from ingestion of foreign material that physically geriatric dogs and cats.
obstructs aboral flow or damages the walls of the GI tract Lifestyle of the pet can significantly affect the likeli-
to the point of rupture. Perforation of the stomach and hood of developing sepsis. Pets that are primarily out-
duodenum can occur secondary to nonsteroidal antiin- doors or that spend a significant amount of time outdoors
flammatory drug (NSAID) administration. Neoplasia and unsupervised are more likely to be exposed to inju-
can cause perforation in any part of the bowel. ries that can result in sepsis.
Disease of organ systems other than the GI tract can
cause septic peritonitis. This occurs most frequently
when a normally sterile organ becomes infected and the History and Clinical Signs
infection extends into the abdomen via perforation or
through translocation of bacteria to the blood or lymph. Patient historical information often relates to the
Extension of infection from the urogenital tract can underlying cause of sepsis. For example, animals with
occur because of prostatitis, prostatic abscess, pyometra, septic peritonitis may have historical complaints such
pyelonephritis or rupture of the urinary bladder contain- as vomiting, abdominal pain or hemorrhagic diarrhea
ing infected urine or calculi. Septic bile peritonitis results while patients with sepsis secondary to pyometra often