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VExUS grade 3 does not always mandate fluid removal.

Venous congestion often stems from fluid overload. However, it’s important to recognize that POCUS does not directly measure blood volume but instead assesses blood flows and pressure gradients. Whether to remove fluid or do something else depends on the clinical context. The following images were obtained from a hospitalized patient with decompensated Group I pulmonary hypertension and acute kidney injury right after right heart catheterization (RHC). Key RHC measurements included a central venous pressure of 15 mmHg, mean pulmonary artery pressure of 37 mmHg, pulmonary vascular resistance of 11 WU, cardiac output of 3 L/min, and a cardiac index of 1.9 L/min/m² while on dobutamine infusion. Interestingly, the pulmonary capillary wedge pressure was only 2 mmHg that increased to 6 mmHg after 500cc of normal saline infusion during the procedure.

These images are consistent with VExUS grade 3. However, due to the low PCWP, diuretics were not initiated to avoid compromising forward flow and consequent worsening hypotension. The problem here is the lung resistance rather than fluid overload; thus, initiating a pulmonary vasodilator would be a more appropriate choice than diuresis or ultrafiltration, though acknowledging that these measures might become necessary based on the clinical course.

Below images were obtained a day after initiating prostacyclin analog infusion (pulmonary vasodilator). While there isn’t significant change in the VExUS grade, there appears to be an improvement in the femoral vein stasis index. Whether this improvement is attributable to technical factors or respiratory phase variation remains debatable, but there was a modest improvement in serum creatinine.

The care was not escalated in accordance with the patient’s wishes, hence further follow-up is not available. Nevertheless, the purpose of this case is to underscore that VExUS should not be used like another ‘lacto-bolo’ reflex and must be interpreted in conjunction with other hemodynamic and clinical variables. A similar scenario may occur when impending cardiac tamponade leads to venous congestion in a dialysis patient; reflexively prescribing 3-4 L ultrafiltration without detecting pericardial effusion can result in the patient deteriorating during dialysis as intracardiac pressure decreases.

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