Wednesday, July 17, 2013

Early goal directed therapy: Patwari Academy video

Via Academic Life in Emergency Medicine. This is a great video. I would like to add some nuance and point to some features that deserve special emphasis.

Early goal directed therapy (EGDT) remains in the new (2012) Surviving Sepsis Guidelines where it is referred to as quantitative resuscitation and protocolized resuscitation.

The lecture starts off with some definitions. He is a little fuzzy on the distinction between severe sepsis and septic shock, but so are the guidelines. They term it sepsis induced tissue hypoperfusion. The concept of septic shock is of practical importance because it defines the patient as being eligible for EGDT and to meet criteria in the septic patient you need either hypotension following the initial fluid boluses or an elevated lactate. You need one or the other, not necessarily both.

Starting at 3:02 the speaker mentions multi-organ dysfunction syndrome (MODS). That's an old term that isn't mentioned much in today's definitions but remains clinically valid. It means just what it says and is the late result of a cascade of injurious mediators and hypoperfusion that starts earlier. The early cascade marks the window of opportunity for interventions. By the time MODS sets in therapeutic efforts are less likely to produce good outcomes. The cascade often presents in the ER whereas MODS more typically is seen hours or days later in the ICU. So concerning the effectiveness of treatment remember: location, location location! The E in EGDT stands not only for early but also for ER. The incentive may be to just get the patient up to the ICU but previous trials with goal directed therapy commencing in ICU showed no benefit. EGDT, in contrast, has been shown to reduce mortality. The objective is to start EGDT in the ER and stave off MODS in the ICU. That's the point he's making at 4:01 in the video.

At 4:23 he mentions the CRASH syndrome. I'd never heard this term though am well familiar with the concept. It is a useful construct and goes like this: although for most infections the initial inflammatory cascade in the ER sets the stage for MODS and death later in the ICU (so that the ultimate consequences of the cascade are not usually seen in the ER) a few exceptional infections are more likely rapidly fatal, or at least rapidly progressive to MODS, right there in the ER. These include meningococcemia, neutropenic sepsis, encapsulated bacterial infections in asplenia, infections in liver failure and necrotizing fasciitis. (MRSA pneumonia is also mentioned though I think that it can appear more indolent on occasion).

At 5:54 he says he would probably intubate most septic patients. I would take issue though I agree with the principle he is trying to invoke. That is, the diaphragm is a big oxygen consumer and lactate generator and it is sometimes helpful in the septic patient to off load it. Intubation may be an underutilized intervention in sepsis though many patients can be managed without it. In fact, the surviving sepsis guidelines mention mechanical ventilation ONLY in those patients in whom sepsis is complicated by ARDS.

Again at 6:47 he talks about the distinction between early goal directed therapy and goal directed therapy, and correctly points out that prior research showed that when goal directed therapy was delayed until arrival to ICU it was not helpful whereas EGDT started in the ER was associated with the NNT of 6.

The discussion of pressors begins at 7:55. Norepi is the front line drug. He lists vasopressin as second to be added as a NE sparing agent. The guidelines, however, list epinephrine as second in line and vasopressin as third.

Try not to be too distracted by the dog whining in the background. The poor pooch sounded starved for attention. 

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