ICUCase#4: Preload and Afterload assessment from Critical Care Echo in cardiogenic shock

60 year old male with no known history admitted to ICU for cardiogenic shock and A fib w RVR. On BiPAP and CRRT. Also on levophed, dobutamine, and amiodarone. Based on VEXUS and Critical Care Echo what do you think of preload and afterload?

1. VEXUS: IVC 2.7 cm

Hepatic Venous Doppler:

S wave reversal (on comparison with IRVD, single diastolic waveform). --> severely abnormal pattern

Portal Venous Doppler:

> 50% pulsatility --> severely abnormal pattern

Intra Renal Venous Doppler:

Discontinuous monophasic --> severely abnormal pattern

Since more than 2 severely abnormal patterns -> VEXUS grade 3 -> severe congestion Now, lets take a look at cardiac ultrasound: 1. PLAX view:

Poor windows, unstable view with respiration.

2. PSAX View:

D sign/Diastolic septal flattening + Hard to assess systolic vs diastolic in A fib here.

By reducing playback speed, diastolic flattening becomes apparent. Suggesting RV volume overload.

3. Apical 4 chamber view:

Moderately reduced EF

4. Mitral valve color doppler:

Central stream: could be functional due to hypervolemia, or structural from dilated cardiomyopathy at baseline

Likely Moderate to severe MR

5. MR Vmax:

325 cm/s

6. Tricuspid valve color doppler:

Likely moderate TR

7. TAPSE & TR Vmax:

TAPSE 12.5 mm, which is < 17 mm --> suggesting decreased RV systolic dysfunction

TR Vmax from Parasternal RV inflow view: 129 cm/s. Not so impressive

8. LVOT VTI and Cardiac Output:

Average LVOT VTI for 3 calculated waveforms-> 8.4 cm.

Suggesting low forward flow.

Calculated Stroke Volume with average HR 110 on above drips = 25 cc.

Cardiac Output 2.8 L/min

Cardiac Index 1.15 L/min/m2

To summarise:

Cardiac functions: SV 25 cc. CO 2.8 L/min, CI 1.15 L/mimn/m2.

Current drips: Levophed 0.54 mcg/kg/min Dobutamine 20 mcg/kg/min (Max dose) Amiodarone 0.5 mg/min

Current Vitals:

Now, What changes would you make in current drips?

1. Increase Dobutamine

2. Increase levophed

3. Decrease levophed

4. Add another agent

Clinical Impression:

Given both TR and moderate MR, along with volume overload. Could likely be functional murmurs.

In current scenario, above valvular regurgitations along with high afterload from levophed can explain above SV and CO.

-> Decrease Levophed is what we did!

We were able to wean down Levo and after clinical stability, could wean down dobutamine later.

Author:

Neev Patel, MD