Taken from my sepsis worksheet from the 3/30 Journal Club on New Sepsis Definitions.
BR– = board relevant
What is SIRS? What is the criteria that comprises SIRS?
Systemic Inflammatory Response Syndrome
Need 2 of the following:
- RR> 20 OR PaCO2<32
- Temp< 96.8 or >100.4
- WBC>12,000 OR <4,000 OR bands >10%
Based on the old definition, clinically, what is sepsis?
SIRS + suspected source of infection
Why has SIRS come out of favor for diagnosing sepsis?
Too much of a focus on inflammation
Inadequate sensitivity (50-70%)and specificity (~30%)
BR — What is sensitivity and specificity?
Sensitivity: true positive rate. Proportion of all people with disease who test positive.
Highly sensitive test means that negative rules out disease (SN-N-OUT)
Specificity: true negative rate. Proportion of all people without disease who test negative.
Highly specific test means that positive rules in disease (SP-P-IN)
Based on the Sepsis-3, what is sepsis?
“Life-threatening organ dysfunction cause by a dysregulated host response to infection.”
Based on the Sepsis-3, how is organ dysfunction defined?
Change in SOFA score ≥2
If no baseline SOFA score exists assume 0 if there is no known organ dysfunction at baseline
BR — What is validity and reliability?
Validity = accuracy -> the trueness of the test measurement (e.g., hitting the bull’s eye)
Systematic error decreases validity
Reliability = precision -> consistency and reproducibility of the test measurement (e.g., clustering of shots)
Random error decreases reliability
Based on the Sepsis-3, what clinical criteria do health care providers use to determine if sepsis is present?
Sequential Organ Failure Assessment (SOFA) score includes the following:
- Platelet count
- Glasgow Coma Scale score
- Administration of vasopressors with type and rate of infusion
- Serum creatinine or urine output
Quick Sequential Organ Failure Assessment (qSOFA) score includes the following:
- RR ≥ 22
- Altered mentation (GCS<15)
- SBP ≤ 100
- ≥2 should prompt completing full SOFA score
Based on the Sepsis-3, how is septic shock defined?
“Sepsis with persisting hypotension requiring vasopressors to maintain MAP ≥ 65 and having a serum lactate >2 despite adequate volume resuscitation”
BR — How do you calculate mean arterial pressure (MAP)?
MAP = CO*TPR
CO = SV*HR = rate O2 consumption/(arterial O2 content – venous O2 content)
MAP = 2/3 diastolic pressure + 1/3 systolic pressure
MAP approximates afterload
BR — What drugs decrease afterload?
Vasodilators: hydralazine, nitroprusside, nitroglycerin
ACE inhibitors: lisinopril
Dihydropyridine calcium channel blockers: amlodipine, nifedipine
BR — What are the class side effects for the following?
Hydralazine – drug-induced lupus (anti-histone antibody mediated)
Nitroprusside – cyanide toxicity
Nitroglycerin – reflex tachycardia
ACE inhibitors – dry cough, angioedema
ARBS – angioedema
CCBs – AV block, flushing
What groups of people are most at risk of developing sepsis?
- older adults
What are the most common infections that lead to sepsis?
BR – What are the most common organisms for pneumonia?
Typical: S. pneumonia, S. aureus, H. influenzae
Atypical: viruses, mycoplasma, legionella, chlamydia
BR – What are the most appropriate empiric antibiotics for pneumonia?
Typical: penicillin/cephalosporin – MOA = binds PBP, blocks transpeptidase. SE = hypersensitivity
Atypical: macrolide – MOA = block translocation by binding to 23S rRNA of 50S subunit. SE = QT prolongation
BR – What are the most common organisms for UTI?
- E. coli
- S. saprophyticus
- K. pneumonia
- Proteus morabilis
BR – What are the most appropriate empiric antibiotics for uncomplicated cystitis?
- Nitrofurantoin –
- TMP-SMX – MOA = TMP inhibits dihydrofolate reductase. SMX inhibits dihydropteroate synthase. SE = Stevens-Johnson syn, teratogen
- Fluoroquinolones – Inhibit DNA gyrase and topoisomerase IV. SE = tendon rupture, myalgia, QT prolongation
- Aminopenicillins – MOA = binds PBP, blocks transpeptidase. SE = hypersensitivity
What is the Surviving Sepsis resuscitation bundle?
TO BE COMPLETED WITHIN 3 HOURS OF TIME OF PRESENTATION:
- Measure lactate level
- Obtain blood cultures prior to administration of antibiotics
- Administer broad spectrum antibiotics
- Administer 30ml/kg crystalloid for hypotension or lactate ≥4mmol/L
What is the Surviving Sepsis management bundle?
TO BE COMPLETED WITHIN 6 HOURS OF TIME OF PRESENTATION:
- Apply vasopressors (for hypotension that does not respond to initial fluid resuscitation) to maintain a mean arterial pressure (MAP) ≥65mmHg
- In the event of persistent hypotension after initial fluid administration (MAP < 65 mm Hg) or if initial lactate was ≥4 mmol/L, re-assess volume status and tissue perfusion
- Re-measure lactate if initial lactate elevated.