Exam 1 - Peritonitis Flashcards
what is peritonitis?
inflammation of the peritoneum
what is primary peritonitis?
spontaneous occurrence with absence of a source of bacterial infection
what is the most common example we see in vet med of primary peritonitis?
FIP in cats
what is the most common form of peritonitis in vet med?
secondary peritonitis
what are some aseptic causes of secondary peritonitis?
bile peritonitis
uroperitoneum
what are some septic causes of secondary peritonitis?
leakage of gi contents
reproductive, biliary, urinary, & pancreatic sources with bacteria
penetrating wounds
T/F: ~60% of canine & ~50% of feline cases of septic peritonitis have a gastrointestinal source
true
what are the major potential sources of gi septic peritonitis?
dehiscence of prior surgical site, foreign body with perforation, ulceration with perforation
others include - necrosis of GDV, neoplasia with perforation, penetrating abdominal injury, necrosis of intussusception site, & dehiscence of gastric/jejunal feeding tube site
when is dehiscence most likely to occur in patients post-op gi surgery? why?
3-5 days
lag phase of wound healing - debridement is occurring & collagenases activity is decreased, so strength of intestines depends on sutures
T/F: prophylactic post-op antibiotics will prevent dehiscence in routine post-op gi surgical patients
false - won’t decrease it
what are some risk factors associated with dehiscence?
delayed enteral nutrition
pre-existing septic peritonitis
hypoalbuminemia (<2-2.5 mg/dL)
linear foreign body
multiple intestinal procedures - multiple enterotomies
administration of blood products
poor surgical technique
where are the most common sites of perforation due to gi ulceration in dogs? what clinical signs are seen?
stomach & duodenum
vomiting, hematemesis, & melena
why is the severity of septic peritonitis dependent on the source of infection?
a higher bacterial load is seen as you move through the gi tract - stomach & proximal small intestines have low-numbers of acid resistant bacteria while the colon has 1000:1 anaerobes to aerobes
e. coli & bacteroides fragilis are most common
what is SIRS? how does an animal qualify the SIRS criteria?
systemic inflammatory response syndrome that is a common sequela to sepsis
must meet 2 or more of the criteria
what is the pathophysiology of SIRS?
mediator excess of cytokines/oxygen free radicals cause widespread endothelial injury & dysfunction
leads to vasodilation, increased capillary permeability, tissue edema, & neutrophil entrapment in microcirculation
see multi-organ dysfunction syndrome
what are the sirs criteria that must be met for cats?
temp - >103.5 or <100
HR - >225 or <140 bpm
RR - >40
WBC - >19,500 or <5,000
what are the sirs criteria that must be met for dogs?
temp - >102.6 or <99
HR - >140
RR - >30
WBC - >19,000 or <6,000
what are some common clinical signs associated with peritonitis?
lethargy, weakness, vomiting/regurgitation, inappetence, increased respiratory effort, & abdominal distension
what makes up the hyperdynamic response that is initially seen in patients with peritonitis? what about the hypodynamic response seen after?
hyperdynamic - fever, red/injected mucus membranes, tachycardia, & bounding pulses
hypodynamic - hypothermia, hypotension, & pale mucus membranes
T/F: bradycardia is more common in cats with peritonitis instead of tachycardia
true
what initial diagnostic labwork should be done for a peritonitis patient?
PCV/TS, electrolytes, lactate, blood glucose, & BUN/creatinine
CBC/chem, & coagulation panel
what is typically seen on abdominal radiographs in a patient with peritonitis? is this used to definitely diagnose peritonitis?
decreased serosal detail, free peritoneal gas
nope
when should you consider doing thoracic rads for a patient with peritonitis?
neoplasia is high on the differential list
suspicion for possible aspiration based on history/physical exam
avoid VD view
this radiograph was taken of a patient with peritonitis - what is seen?
free peritoneal gas
why should an abdominal ultrasound be done for a patient with peritonitis?
assess for free abdominal fluid
what is the most useful diagnostic test for septic peritonitis?
abdominocentesis!!!! put fluid in an EDTA tube & culture it
what does the gross appearance of peritoneal fluid look like in a patient with peritonitis?
serosanguinous, bloody, purulent - all possible
what does the cytology of peritoneal fluid look like in a patient with peritonitis?
toxic & degenerative neutrophils with INTRACELLULAR BACTERIA +/- vegetable material
______ is required for source control in animals with septic peritonitis
surgery
T/F: peritonitis has a 30-50% mortality rate in small animal patients
true
what are some poor prognostic indicators of peritonitis?
refractory hypotension, elevated lactate without response to resuscitation, respiratory distress, cardiovascular collapse, DIC, & MODS
with a gi source causing septic peritonitis, what should you look out for? why?
recurrent sepsis (dehiscence of your surgical site)
increases mortality rate to 60%
what does your glucose & lactate measurements off of peritoneal fluid look like in a patient with septic peritonitis?
glucose - fluid glucose <50mg/dL, >20mg/dL peripheral whole blood: fluid difference, or plasma:fluid difference of >38mg/dl may be more sensitive
lactate - fluid lactate >2.5 mmol/dL (dogs, blood: fluid difference of -2.0mmol/L (dogs
what must be done prior to pursuing surgery in an animal with septic peritonitis?
stabilize!!! goal directed resuscitation with close monitoring of the BP, HR, temperature, SpO2, lactate, & BG
if your patient with septic peritonitis has hypoalbuminemia, what fluids should be considered?
plasma or a colloid for shock doses of fluid
T/F: blood pressure support may be indicated in patients with septic peritonitis
true - pressors may be necessary - norepinephrine often considered 1st in septic patients
what antibiotics are often used for treating septic peritonitis?
broad spectrum - ampicillin/sulbactam + enrofloxacin
ampicillin/sulbactam alone
3rd generation cephalosporin
T/F: in patients with septic peritonitis, empirical selection of antibiotics is not associated with survival but timing is
true - IV ASAP, ideally within 1 hour of diagnosing
what is the #1 requirement for treating septic peritonitis?
surgery
what are the goals of surgery in a patient with septic peritonitis?
full abdominal explore
source control
lavage
+/- drainage
why should you anticipate complicated anesthesia in patients with septic peritonitis? how do you minimize these risks?
vasodilation occurs from sepsis, so they are more sensitive to the hypotensive side effects of drugs
minimize time under anesthesia - prep as much as possible before induction
MAC sparing, multi-modal protocol is critical - may even consider TIVA with no gas inhalant
what is the most common procedure performed in patients with septic peritonitis when the gi tract is identified as the source? when is this not possible? what is done instead?
R&A
perforated duodenal ulcers - debride & close the gi in this situation reinforcing the closure with omentum or serosal patch
T/F: multiple studies suggest that GI staplers perform better than hand sutured anastomosis sites
true - decreased risk of dehiscence when the transverse staple line is oversewn
how do you want to lavage the abdomen of a patient with septic peritonitis?
minimum of 200-300ml/kg recommended using warm sterile saline (want what you’re suctioning back to be clear)
aim to reduce bacterial load, debris, & inflammatory cells - DO NOT ADD ABX TO IT, not necessary & may induce chemical peritonitis
obtain a closing culture (both aerobic & anaerobic)
T/F: it is okay to place a penrose drain in the abdominal cavity
false - VERY BAD DO NOT DO THIS
T/F: there is a lot of debate on drainage techniques for patients with septic peritonitis
true - JP drain is safest in absence of advanced ICU/training
why should a penrose drain never be placed in the abdominal cavity of a dog with septic peritonitis?
not appropriate for abdominal drainage
cannot be used in the abdominal cavity (they become quickly walled off and allow ingress of bacteria) or the thoracic cavity (they allow air to pass into the thorax!!!)
what is a JP drain? when should you consider using it for a patient with septic peritonitis?
active, closed suction drain with fenestrations & one-way valve where you can monitor fluid volume & character closely
consider when there is severe contamination in the abdomen you can’t adequately remove/lavage
why should you use caution with interpretation of chemistry/cytology of drain fluids in post op septic peritonitis patients?
over-interpretation is common - not a reliable as a sole predictor of dehiscence
in post-op septic peritonitis patients, how much fluid was collected in the drains daily? what lab abnormalities were commonly seen in these animals?
47 +/- 25 ml/kg/day
hypoproteinemia in 90% of animals
anemia in 80% of animals
what monitoring should be done in post-op septic peritonitis patients 24/7?
continuous ECG, blood pressure, PCV/TS, albumin, lactate, glucose, & cbc chem every few days
T/F: early enteral nutrition is important in patients with septic peritonitis
true - consider placing a feeding tube at the time of surgery
T/F: you need to keep up with fluid losses through the JP drain if you placed one in a patient with septic peritonitis
true
