Today on the podcast, a bunch of hemodynamics. Originally, this was going to be an interview with Phillipe Rola, friend of the show and Intensivist extraordinaire. Phil surprised me by bringing 3 other friends and authors of the papers discussed:
- Korbin Haycock, MD
- Rory Spiegel, MD
- Jon-Émile Kenny, MD
We primarily discuss the 3 papers below in addition to a ton more on ultrasound and hemodynamics.
All Things IVC
venous return is mediated by Pmsf (elastic recoil of the venous system) and CVP
don't want to push past the flat portion of the Starling curve
May be a good indicator of fluid tolerance
CVP above 12 is associated with microcirculatory dysfunction
Plethoric Index to Evaluate IVC with Right Heart Failure
Shoc-IV
dilated IVC (>2.5) without resp variation had a good LR + for fluid overload
The 4-Quadrant Hemodynamics/Ultrasound Approach
The Paper
unifying_fluid_responsiveness_and_tolerance
Diamond-Forrester Hemodynamic Profiles
Dry and Wet specifically refer to pulmonary edema and/or organ congestion
1. Warm & Dry
Normal CI, Low PAOP
LVOT VTI >= 18 and VEXUS 0 or 1
suggests vasodilation as cause for hypotension
Once you start a vasoconstrictor, the patient may move to Profile 2 or 4
2. Warm & Wet
Normal CI, High PAOP
LVOT VTI >=18 and VEXUS 2 or 3
Start a vasoconstrictor
Consider diuresis, consider checking fluid responsiveness first as a non-responsive patient may tolerate diuresis better than a fluid responsive one. Fluid responsiveness may indicate an end-point for diuresis–note: you do not have to actually give the fluid even if fluid responsiveness is indicated (See below for the fluid responsiveness rates per quadrant)
3. Cold & Dry
Low CI, Low PAOP
LVOT VTI < 18 and VEXUS 0 or 1
May be fluid down, but can also be vasodilation with preexisting diastolic or septic diastolic dysfunction
May be only time for empiric fluid challenge
Low VR and Septic Diastolic Dysfunction
4. Cold & Wet
Low CI, High PAOP
LVOT VTI < 18 and VEXUS 2 or 3
Likely primary pump dysfunction
Hot or cold to touch
Inotropes–they should move to quadrant 3 or 1
sometimes these pts will benefit from diuresis as well
VTI Grey Zone
between 16-20 to make up for measurement imprecision
in between is lukewarm
Fluid Responsiveness by the 4 Quadrants
Additional New Information
- Muñoz, F., Born, P., Bruna, M. et al. Coexistence of a fluid responsive state and venous congestion signals in critically ill patients: a multicenter observational proof-of-concept study. Crit Care 28, 52 (2024). https://doi.org/10.1186/s13054-024-04834-1
More on EMCrit
Additional Resources
- EMCrit 373 – Mike Weinstock with another Critical Care Bounceback: “Asymptomatic Hypertension” - April 18, 2024
- EMCrit Wee – Ross Prager on 10 Heuristics for the New ICU Attending - April 13, 2024
- EMCrit 372 – FoundStab Intubation SOP - April 5, 2024
So if you have given a patient in category 1 a vasoconstrictor and they have moved to 4, they now need an inotrope. Since the only agents we have are either inopressors or inodilators, my stance has always been to not give them inodilators (dobutamine), since it would counter my already established vasopressor-therapy (increase needed dose of norepi or vasopressin). They would rather need epi and/or diuresis. But my colleages are often scared of giving epi, and they are scared of diuresing a patient who is in shock. How are you guys doing it? Are you giving inodilators to patients… Read more »
would be epi for me all the way
Epi is a very reasonalble choice. An inodilator in some situations may be good too, so long as you increase CO more than you decrease afterload. Ideally, what would happen with an inodilator is that the MAP would increase (if you gained more CO than the loss of afterload), the CVP would decrease with an increase in cardiac efficency, and the gap between MAP and CVP would thus decrease–all favoring the perfusion at the level of the capillaries. An inodilator gets you shifted back to quadrant 1 as the inotrope increases contractillity and the vasodilation decreases afteroad, also shifting the… Read more »
About heart rate: We agree that we rather have our patients going 110 instead of 70. What about a septic shock patient who is in afib of 130-150 (either new afib or chronic)? They often look congested because of their diastolic dysfunction, but are they really hypervolemic? In my surgical cohort it’s often hypovolemia which triggers tachycardic afib, but volume challenges are directly shifted into their pleural space 🙁 After you managed their electrolytes, pain, agitation etc., what do you do with these patients before giving them amio? (or are there any alternatives? I.v. digitalis is not available in Europe… Read more »
i would try Mag first