Defining away sepsis

Why do we need new definitions for sepsis? We want the term to denote a syndrome with serious consequences, something that needs the full force of an ICU to recover.

No simple infections. So not a young girl with viral feverish URI (who happens to have leucocytes < 4). Neither a simple pneumonia. Maybe the myriad of negative sepsis studies stem from the fact that they included too many simple infections. What used to constitute severe sepsis, the endangered endorgans should become requisite in the definition of sepsis.

High sensitivity. What about the 90 yo dehydrated nursing home resident with positive nitrite stick and altered mental status? He might recover with some fluids and antibiotics, but then he also might not and deteriorate, so that he needs treatment response monitoring – he could be septic, but he also could just be cured in 2 hours.

I see the recent initiative to improve our definition of sepsis (dubbed Sepsis 3.0 by the FOAMED community) in this light. While the new definitions sound a bit esoteric, they are actually very practical, focussing on two situations:

  • Non-ICU: The normal ward, private practice or ER, where we need to recognize those patients with suspected infection that might deteriorate and need close monitoring, while ressources are not that good, that every patient can have an arterial blood or extensive lab works. Sepsis 3.0 recommends to use the qSOFA, also known as BAT score, where 2 out of 3 criteria suffice.
    • Blood pressure < 100
    • Altered mental status
    • Tachypnea 22 breaths/min
  • In ICU, we should screen with the daily labs we already have, using the SOFA score (routinely computed in electronic charts, also called CAR-LOG = coagulation-arterial pressure-renal-liver-oxygenation-GCS) and use a 2 point change as a threshold for sepsis, if infection is suspected. Septic shock is defined by need for noradrenaline to keep the MAP above 65 with remaining lactate geq 2 mmol/l, provided that enough fluids have been given.

Who is suspected? The beauty of the old and new definition of sepsis that “suspected infection” is not further specified. You might be warned by fever, CRP or leucocytosis, but also by a good story for an infection (postoperative patient, smelly urine). While some folks find this too vague, I think we always know when to suspect infection.

Think of sepsis when organs bail out. The article reminds us to think of sepsis (and thus suspect infection), whenever any organ failure occurs.





Cristalloids vs. colloids

I used to grow up with Macrodex and Promit on our ambulances. Then HAES came about and some albumin. In the first decade of this century, HAES fell into the abyss of the VISEP study, leaving gelatine for colloids. Now there is again evidence against that, so that we are left with albumin (some evidence for sepsis – see the SAFE study) and cristalloids and maybe some obscure stuff.

This course of modern volume therapy, in particular for sepsis, is beautifully illustrated by this ingeniously crafted study, which correlates acute kidney injury with the current volume replacement fluid of choice.

I am happy to say after at least 30 years of bitter debate that colloids have no place in volume replacement anymore, perhaps with the exception of Albumin and Macrodex (for which no proper data on harm exists). At least that is what the recent recommendations of ESCIM and Cochrane’s say (though with slightly more paragraphs). There might be some instances (cirrhosis, say) where albumin is particularly good, but that still has to be determined.