# Perfusion and Congestion: Two Sides of AKI

Address the cardiac, hepatic, infectious, or medication driver and evaluate intrinsic injury when the course does not fit a purely functional explanation.

![Infographic: Perfusion and Congestion: Two Sides of AKI](https://urinenephrology.org/visual-reference/images/mastery-prerenal-congestion.png?v=20261003c)

## Effective arterial filling

Kidney perfusion depends on more than total body water. Heart failure and cirrhosis can reduce effective arterial filling while substantial edema is present.

## Recognize mixed physiology

Hypotension, venous congestion, vasodilation, infection, and drug effects can coexist. A swollen patient may still have impaired renal perfusion.

## Assess both compartments

Use history, examination, weight and fluid trends, urine findings, and focused imaging when useful. No single laboratory ratio defines the hemodynamic problem.

## Test the hemodynamic hypothesis

Depletion with poor perfusion may justify a carefully reassessed fluid intervention. Elevated venous pressures with pulmonary congestion may instead require decongestion. Document the intended response—perfusion, respiratory status, urine output—and reassess before repeating the same intervention.

## Interpret creatinine during decongestion

If breathing and congestion improve while perfusion remains adequate, a creatinine rise is not by itself a reason to reverse all fluid removal. If hypotension, worsening oliguria, or other hypoperfusion appears, reassess the rate, target, medications, and possibility of intrinsic injury.

## Treat the whole syndrome

Address the cardiac, hepatic, infectious, or medication driver and evaluate intrinsic injury when the course does not fit a purely functional explanation.

## Source lessons

- [prerenal aki cardiorenal hepatorenal review](https://urinenephrology.org/mastery/aki-advanced/prerenal-aki-cardiorenal-hepatorenal-review.html)
- [comprehensive cardiorenal report](https://urinenephrology.org/mastery/cardiorenal/comprehensive-cardiorenal-report.html)

Read alongside the full lessons; the findings and decisions shown here require the stated clinical context.