Peritonitis

Question 1

What is the flow of circulation in the peritoneum ?

Answer 1

Along ventral abdominal wall —> dorsal along diaphragmatic surface of liver —> through lymphatics into mediastinal LNs —> systemic circulation

Question 2

What are causes of primary peritonitis?

Answer 2

Spontaneous inflammation in the absence of intraperitoneal source

• corona virus —> FIP
• gram positive organisms are more common and usually MONOBACTERIAL

Question 3

What are causes of a secondary peritonitis ?

Answer 3

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

Question 4

T/F: surgery is usually indicated for primary peritonitis but is NOT for secondary peritonitis

Answer 4

False

Surgery is NOT indicated for primary peritonitis but IS for secondary

Question 5

The majority of septic peritonitis have what origin?

Answer 5

GI

• mechanical perforations, trauma, ruptured neoplasia, vascular disruption, leading to ischemia/necrosis, surgical dehiscence

Question 6

T/F: steroids more commonly induce ulceration in the large colon

Answer 6

True

Question 7

How does does location of GI perforation affect bacteria?

Answer 7

Aboral —> higher total bacterial counts with and more anaerobes

Question 8

What are the two main bacteria from the bowel that cause a septic peritonitis?

Answer 8

Ecoli. —> alpha hemolysin endotoxin

Bacteroides fragilus (anaerobic) —> enhances lethal potential of Ecoli

Question 9

What are other sites that a septic peritonitis can arise from?.

Answer 9

Hepatobiliary
Urogenital

Iatrogenic

Pancreatic
Splenic
Penetrating trauma
Lymph node

Question 10

What are the local manifestations of septic peritonitis?

Answer 10

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

Question 11

What are the systemic manifestations of septic peritonitis ?

Answer 11

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

Question 12

What are the terminal effects of septic peritonitis?

Answer 12

DIC (disseminated intravascular coagulation)

SIRS (systemic inflammatory response syndrome)

MODS (multi organ dysfuntion syndrome)

Question 13

What are clinical signs of septic peritonitis?

Answer 13

Painful, vomiting, fever, and distended abdomen, +/-shock

Question 14

What are the two phases of shock with a septic peritonitis?

Answer 14

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.

Question 15

What clinical signs do you see in cats with septic peritonitis?

Answer 15

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

Question 16

How long can FREE air mean in the abdomen after surgery?

Answer 16

Up to 30days

Question 17

What is the gold standard for assessing peritonitis ?

Answer 17

Cytology

• > US guided FNA - aFAST
• > Blind “4quadrant” abdominocentesis
• > diagnostic peritoneal lavage (DLP) - washes peritoneal surface if low volume effusion

Question 18

What would you see on cytology that would indicate septic peritonitis?

Answer 18

Degenerative neutrophils with intracellular bacteria

only 57-87% accurate

Question 19

What are contraindications for abdominocentesis?

Answer 19

Coagulopathy

Organometallic and extreme distention of an abdominal viscus

Question 20

How does glucose and lactate in abdominal fluid compare to blood concentration in a case of septic effusion in dogs?

Answer 20

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

Question 21

How can you determine source of the peritonitis?

Answer 21

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

Question 22

T/F: recent surgery will cause a mild, non-septic peritonitis with mature nontoxic neutrophils < 10,000WBC/ul

Answer 22

True

Question 23

What is the treatment for septic peritonitis?

Answer 23

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

Question 24

What is the best choice for empirical antimicrobial selection in a spetic peritonitis?

Answer 24

Four Quadrant therapy

• IV amplicillin/ aminoglycoside/ metronidazole
• IV ampicillin/ enrofloxacin (bay trail)/metronidazole

Question 25

What is usually involved in surgery of a spetic peritonitis?

Answer 25

Repair or remove inciting cause (intestinal resections and anastomosis/ cholecystectomy/ liver lobectomy/ partial cystecomy/ nephrectomy)

Lavage*** (warm isotonic saline)

PR enteral nutrition

PO drainage!!!!

Question 26

What are the drainage options for PO peritonitis surgery?

Answer 26

Primary closure — if source of infection has been isolated and completely controlled

Open
—> gravity dependent = dressing packed within “open” incision n
—> vacuum assisted closure

Closed
—> passive - multi luminal/penrose/column disk catheters
—> Active - closed suction (Jackson Pratt)

Question 27

What are the pros and cons to pen peritoneal drainage ?

Answer 27

PRO

• most efficient way to drain
• limit anaerobic contamination

CON

• labor intensive management
• nosocomial contamination risk
• electrolyte imbalances
• 2nd surgery procedure to close abdomen

Question 28

What are the pros and cons of peritoneal drainage?

Answer 28

PRO

• lower risk of nosocomial infection
• lower potential for evisceration
• less PO bandage care
• no additional sx to close abdomen

CON

• occlusion (omentum/clot)
• ascending bacterial contamination

Question 29

What is Dr Cavanaugh preferential choice for abdominal drainage.. even though there is no significant difference between the use of the different techniques?

Answer 29

Closed suction - Jackson Pratt

Question 30

What is the most common source of contamination and mortality rate associated with Jackson Pratt drains?

Answer 30

Dehiscence of previous anastomosis

Mortality rate = 15%

Question 31

What are the negative prognostic factors for septic peritonitis?

Answer 31

Decreased pre- or intra-, or P BP
Presence of DIC
If an ineffective antibiotic was selected before culture and sensitivity results were obtained