Peritonitis Flashcards
What is the flow of circulation in the peritoneum ?
Along ventral abdominal wall —> dorsal along diaphragmatic surface of liver —> through lymphatics into mediastinal LNs —> systemic circulation
What are causes of primary peritonitis?
Spontaneous inflammation in the absence of intraperitoneal source
- corona virus —> FIP
- gram positive organisms are more common and usually MONOBACTERIAL
What are causes of a secondary peritonitis ?
Consequence of an underlying primary decease process (common)
- bowel leakage/translocation, urine/blood/bile extravasation, neoplastic, pancreatitis
Gram negative organisms are more common and usually POLYMICROBIAL
T/F: surgery is usually indicated for primary peritonitis but is NOT for secondary peritonitis
False
Surgery is NOT indicated for primary peritonitis but IS for secondary
The majority of septic peritonitis have what origin?
GI
- mechanical perforations, trauma, ruptured neoplasia, vascular disruption, leading to ischemia/necrosis, surgical dehiscence
T/F: steroids more commonly induce ulceration in the large colon
True
How does does location of GI perforation affect bacteria?
Aboral —> higher total bacterial counts with and more anaerobes
What are the two main bacteria from the bowel that cause a septic peritonitis?
Ecoli. —> alpha hemolysin endotoxin
Bacteroides fragilus (anaerobic) —> enhances lethal potential of Ecoli
What are other sites that a septic peritonitis can arise from?.
Hepatobiliary
Urogenital
Iatrogenic
Pancreatic
Splenic
Penetrating trauma
Lymph node
What are the local manifestations of septic peritonitis?
Peritoneum —> severe inflammation (fibrin deposition) and release of vasoactive substances (histamine, cellular proteases, and microbial endotoxins)
Immune system —> humoral opsonins, antibodies, and complement activated
Release of cytokines (TNFa and IL1 and 6)
Digestive system —> ileus secondary to inflammation, poor perfusion of the GI tract, ischemia and bacterial translocation
What are the systemic manifestations of septic peritonitis ?
Cardiovascular. — cytokines lead to reduced CO, arterial dilation, and reduced venous return (hypotension)
Urinary — decreased renal perfusion decreased GFR —> increased BUN, toxins, K and H
Respiratory —> decreased O2 delivery —> anaerobic metabolism and lactic acid production —> reduced renal blood flow also limits the metabolic pathways for eliminating excess hydrogen ions
Coagulation —> bacteria/endotoxins and inflammatory cells and their cytokines —> endothelial damage and expression of tissue factor —> general activation of coagulation cascade
What are the terminal effects of septic peritonitis?
DIC (disseminated intravascular coagulation)
SIRS (systemic inflammatory response syndrome)
MODS (multi organ dysfuntion syndrome)
What are clinical signs of septic peritonitis?
Painful, vomiting, fever, and distended abdomen, +/-shock
What are the two phases of shock with a septic peritonitis?
Hyperdynamic — vasomotor dysfunction, cytokine-induced peripheral vasodilation, tachycardia, hyperemic MMs with rapid CRT, bounding pulses and hyperthermia
Hypodynamic — decreased contractility and CO. = pale MM with CRT>2seconds, weak peripheral pulses, hypothermia and increased RR/HR, dehydration, and dull mentation.
What clinical signs do you see in cats with septic peritonitis?
No pain on abdominal palpation (38%)
Relative BRADYCARDIA <140bpm
- HR= inappropriately low for the hemodynamic status of cats
- secondary to increased vagal tone or cytokine-associated myocardial depression
How long can FREE air mean in the abdomen after surgery?
Up to 30days
What is the gold standard for assessing peritonitis ?
Cytology
- > US guided FNA - aFAST
- > Blind “4quadrant” abdominocentesis
- > diagnostic peritoneal lavage (DLP) - washes peritoneal surface if low volume effusion
What would you see on cytology that would indicate septic peritonitis?
Degenerative neutrophils with intracellular bacteria
only 57-87% accurate
What are contraindications for abdominocentesis?
Coagulopathy
Organometallic and extreme distention of an abdominal viscus
How does glucose and lactate in abdominal fluid compare to blood concentration in a case of septic effusion in dogs?
Peritoneal fluid glucose will ALWAYS be lower (by 20points) than the blood glucose concentration —> 100% sensitive and specific for septic peritoneal effusion
Lactate with be 2points higher in belly fluid (due to anaerobic metabolism and lactic acid production by bacteria in peritoneum
How can you determine source of the peritonitis?
Fluid analysis
Urogenital source — peritoneal fluid creatinine concentration > serum
Bile peritonitis — peritoneal fluid bilirubin concentration > 2.5x serum bilirubin concentration is 100% diagnostic for bile peritonitis
T/F: recent surgery will cause a mild, non-septic peritonitis with mature nontoxic neutrophils < 10,000WBC/ul
True
What is the treatment for septic peritonitis?
Provide hemodynamic support
- aggressive parenteral fluid (crystalloid/colloid)
- blood product administration
- initiation of broad spectrum antibiotics
- analgesia (CRI best)
Emergency surgery
- reduce contamination
- prevent further
What is the best choice for empirical antimicrobial selection in a spetic peritonitis?
Four Quadrant therapy
- IV amplicillin/ aminoglycoside/ metronidazole
- IV ampicillin/ enrofloxacin (bay trail)/metronidazole
