325 Severe Sepsis and Septic Shock Flashcards
When an infectious etiology is proven or strongly suspected and response results in hypoperfusion of uninfected organs
Sepsis/ Severe Sepsis
Sepsis accompanied by hypotension that cannot be corrected by the infusion of fluids.
Septic shock
Signs of organ hypofunction in sepsis - Cardio wise?
Cardio : SBP <90 or MAP <70
Signs of organ hypofunction in sepsis - Renal wise?
Renal: Urine output <0.5 mL /kg per hour
Signs of organ hypofunction in sepsis - Respi wise?
Respi: PaO2/Fio2 <250 or if the lung is the only dysfunctional organ, <200
Signs of organ hypofunction in sepsis - Hematologic?
Hema: Platelet <80 or 50% decrease in platelet count (3 days)
ABGs in sepsis? Plasma Lactate levels?
Unexplained metabolic acidosis pH < 7.3, base dficit >5 meq/L
Plasma lactate >1.5x ULN
Septic shock that lasts >1hr and does NOT respond to fluid or pressor
Refractory septic shock
Blood cutlures yield bacteria or fungi in how many percent of cases?
20- 40 % only
Most common isolate in sepsis
62% were Gram negative bacteria
Pseudomonas and E.coli
Commensal aerobic and facultatively anaerobic gram negs that trigger severe sepsis and septic shock (E.coli, Klebsiella and Enterobacter) has this structure.
Lipid A
This organism has hexaacyl LPS that shields them from host recognition by its polysaccharide capsule.
Neisseria meningitidis
These organisms has Lipid A with fewer than 6 acyl chains - induce very little inflammation, when they do it is after they have multiplied to high densities in tissues and blood.
Gram negative - Yersinia, Francisella, Vibrio vulnificus, Pseudomonas aeruginosa and Burkholderia
Hallmark of the local inflammatory response, may help wall off invading microbes and prevent infection and inflammation from spreading to other tissues
Intravascular thrombosis
Major procoagulant cytokine, an important stimulus to the hypothalamic-pituitary-adrenal axis
IL-6
In severe sepsis, leukocyte hyporesponsiveness has been associated with increased risk of dying - the most predictive biomarker is
a decrease in expression of HLA-DR class II
Major mechanism for Multiorgan Dysfunction
Vascular endothelial injury
Hallmark of septic shock
Decrease in peripheral vascular resistance despite increased levels of vasopressor catecholamines
Risk of developing severe sepsis depends on primary site of infection: severe sepsis is likely to arise eightfold if associated with what sources?
pulmonary or abdominal source
Organisms that produce super antigens
S. aureus, S. pyogenes
Absence of fever is common among which septic patients?
Neonates, elderly, persons with uremia or alcoholism
Cutaneous lesion seen in neutropenic patients - bullous lesion surrounded by edema undergoes central hemorrhage and ncerosis
Ecthyma gangrenosum (p. aeuruginosa)
In absence of pneumonia or heart failure, progressive diffuse pulmonary infiltrates and arterial hypoxemia occuring within 1 week of known insult indicates?
ARDS
Cardiac effects of sepsis
depression of myocardial function, increased end diastolic and systolic ventricular volumes with decreased EF (develops within 24 hours in most patients with sepsis)
