"Dry (#COVID19) lungs are happy lungs." This is the last line of this thoughtful piece on @MGHMedicine's FLARE: us19.campaign-archive.com/?u=ef98149bee3… Well balanced concerns with fluid loading vs aggressive diuresis. I'd like to add some thoughts.... (1/13) 
Goal is euvolemia (Duh?). Easy to say but, WTH is euvolemia anyway?. Let's be honest, fluid therapy has always been about keeping the kidneys happy. Two examples of this #nephrocentric approach to fluids (one from FLARE, one from @jlvincen) (2/13)
Non of this is wrong. Definitely hypovolemic patients (vomiting, diarrhea, and poor oral intake) will benefit from fluids. However, the emphasis of fluid therapy tailored to creatinine ignores that most Sepsis-induced AKI is NOT VOLUME RELATED! (3/13)
Most data on AKI in sepsis (S-AKI) shows ⬆️renal blood flow (RBF) + microvascular dysfunction (PMID: 31443997, 27661757). This should not improve with fluids. In fact VOLUME related AKI is rare in sepsis. Both pre-renal AKI and Renosarca exist. But again, these are RARE (4/13)
1⃣Pre-renal: % of fluid responsive pts in FACTT was 25%. But this does not predict renal response. ≃ 50% of oliguric patients show ⬆️UOP with fluid bolus, but this has NO correlation w ⬆️Cardiac Output (So this is likely 2/2 solute/water diuresis and not better perfusion) (5/13)
2⃣Renosarca is rare too. In FACTT, CVP in the liberal fluid strategy group was higher w no difference in Renal outcomes. Although ⬆️ CVP is clearly associated with AKI in sepsis, as @VelezNephHepato likes to say: Retrospective data can't show causality (AKI can cause ⬆️CVP)(6/13)
Renosarca does exists though (Type 1 Cardiorenal Syndrome). And we've all seen decongestion in❤️ failure improve kidney function. Even if Cr increases a bit with decongestion, this leads to better long term outcomes #PermissiveHypercreatinemia (7/13)
When CVP is ⬆️ enough, back pressure to splacnic veins can reach the flat part of the compliance curve. Then, mechanical power from the ❤️ can reach parenchymal venules and cause organ congestion. The degree to which this happens can be evaluated using #VExUS score (8/13)
Portal Vein Pulsatility>50% (#VExUS 3) was the most powerful predictor of severe AKI in cardiac surgery pts (HR 5.12) (PMID 30371304). #VExUS score outperforms CVP in predicting AKI in this population (PMID 32270297) Great work by @ThinkingCC @EMNerd_ @WBeaubien @khaycock2!(9/13)
Can septic patients have renosarca? TOTALLY. This is especially important in patients with preexisting heart failure, but certainly LV/RV failure can be caused by sepsis or its treatment. (10/13)
As we gather more evidence, it will become apparent that evaluation of volume status is ASYMMETRICAL: Congestion can be objectively evaluated but there is no real test for hypovolemia. Both euvolemic and hypovolemic patients are "fluid responsive" thinkingcriticalcare.com/tag/fluid-resp… (11/13)
Objective tests (#EchoFirst #VExUS) can detect venous congestion; Evaluating hypovolemia is only possible though clinical hx (N/V, ⬇️PO) and chart review (ins n outs). Not all "fluid responsive" pts benefit from fluid. Severly congested patients might respond to diuretics (12/13)
Performing a "Fluid Responsiveness" should only come AFTER it's been clinically determined that patient might be hypovolemic (Clinical hx and chart review) and NOT just for some UOP, Creatinine or lactate level. Remember: In this pandemic, most AKI will not be related to volume.
