Podcast 1 - Sepsis Multicast

In Show #1/5 we will provide an introduction to the series, review some sepsis core content and discuss the debated "septic, normotensive, LA >4" patient.

 

Core Content Review

 (from Marino's ICU Book or elsewhere as cited)

  • Pathophysiology:
    1. Microbial invasion precipitates inflammatory response through release of inflammatory cytokines (mainly  IL-1α, IL-1β, IL-6, and TNF-α). The hope is to eliminate the threat without affecting the host.
    2. Persistent/widespread inflammation produces tissue damage.
    3. Damaged tissue triggers more inflammation.
    4. Proinflammatory cytokines promote dysregulated coagulation which begets more tissue damage and inflammation.
    5. Neutrophils are activated by inflammatory cytokines and undergo a respiratory burst. O2 consumption increases and reactive oxygen species (ROS) are generated, released via degranulation. 
    6. ROS cause further tissue damage and activation of the inflammatory response.
    7. The INFLAMMA-CO-OXIDATIVE HURRICAINE is a self-sustaining process that ultimately produces organ dysfunction.
  • See these open access articles on organ dysfunction in sepsis for more information.

 

Definitions & Criteria

  • The definition of sepsis is 'a life threatening condition that arises when the body's response to infection injures its own tissue.'
  • Diagnostic Criteria for sepsis vary

 

OLD sepsis criteria 

Systemic inflammatory response syndrome (SIRS) 

2/4 of the following

  • Temperature >38°C or <36°C
  • HR > 90 bpm
  • RR >20/min or pCO2 < 32 mmHg
  • WBC >12k or <4k or >10% bands

(SIRS + does not necessarily = infection)

Sepsis

SIRS + documented or suspected infection

 

Severe sepsis

Sepsis + organ dysfunction

Organ dysfunction, defined as:

  • Sepsis-induced hypotension
  • Lactate > 4
  • UOP < 0.5mL/kg/hr > 2hrs
  • PF ratio  < 250 without PNA
  • PF ratio < 200 w/ PNA
  • Creatinine > 2.0mg/dL  
  • Bilirubin > 2mg/dL  
  • Platelet count < 100,000 µL
  • Coagulopathy (INR > 1.5)

Septic shock

Severe sepsis + hypotension refractory to adequate volume resuscitation

Typical pattern = distributive: low CVP / high CO / low SVR

Multiorgan dysfunction syndrome (MODS)

Severe sepsis w/ involvement of more than one organ system

 

Multiorgan failure (MOF)

Subsequent failure of multiple organ systems

 

 

New criteria from @FOAMpodcast

  • Severe sepsis is OUT
  • Sepsis and septic shock remain

Sepsis

Documented / suspected infection

+

  • 2/3 qSOFA (HAT)
  • Hypotension (SBP < 100)
  • Altered mental status (GCS <15)
  • Tachypnea (RR >22)

OR

Rise in SOFA score by > 2

Mortality 10%

Septic shock

Sepsis

+

Persistent hypotension requiring pressor support for MAP >65

AND

Lactate > 2

Mortality 40%

 

Sequential Organ Failure Assessment (SOFA) score

A mortality prediction score that assesses the degree of organ dysfunction in 6 different systems:

  1. Respiratory
  2. Nervous
  3. Cardiovascular
  4. Liver
  5. Coagulation
  6. Kidneys

 

See MDCALC's Clinical Scoring tool

 

We conclude our episode in discussing that the hallmark of sepsis care is probably just frequent re-evaluation and early intervention.