Renal Trauma
Renal trauma is managed by haemodynamic stability first — the stable patient is staged by CT and usually managed conservatively, while instability (not the injury grade alone) drives intervention.
The big picture
Most renal injuries are blunt and low-grade, and the kidney has a remarkable capacity to heal. The trauma framework is always the same: resuscitate and assess stability first (ABCs), then in the stable patient define the injury with contrast CT including delayed (excretory) images, grade it, and choose the least invasive option that works.
Stability first: stable → stage with CT (with delayed images) and observe most injuries; unstable from a renal source → angioembolisation or surgery. Don't let the grade alone send a stable patient to theatre.
Red flags
Resuscitate; angioembolisation if stabilisable, otherwise operative exploration.
Suspect renal pedicle/artery injury — time-critical, salvage window is short.
Haematuria severity does not track injury severity — image by mechanism and stability.
Mechanism pathway
Tap any step to see why it happens.
Diagnostic algorithm
Each step answers one question. Tap to expand.
Treatment ladder
Use the least invasive effective option: observe the stable patient (even high-grade), embolise active bleeding, and reserve surgery for instability or failure.
Complications
- Haemorrhage/shock
- Urinoma and urinary fistula
- Renal loss
- Renovascular hypertension (Page kidney)
- Embolisation: non-target infarction
- Surgery: nephrectomy/blood loss; non-target injury
- Stage properly with delayed images
- Choose least invasive effective option; preserve nephrons
- Embolise delayed bleeding
- Drain/stent urinary collections
- Treat hypertension
If treatment fails
If a conservatively managed injury declines, ask: is this ongoing/delayed bleeding, an enlarging or infected urinoma, or a developing pseudoaneurysm/AV fistula?
Memory hooks
Stability first, grade second.
Stable → CT with delayed images → observe.
Bleeding but stabilisable → embolise.
Unstable from the kidney → operate.
Haematuria amount ≠ injury severity.
Board traps
Stable high-grade injury → answer is observation, not immediate nephrectomy.
No delayed-phase CT → missed urinary extravasation.
Deceleration + non-enhancing kidney → renal artery injury, not parenchymal laceration.
AAST I–V: I = contusion/subcapsular haematoma; II = laceration <1 cm, no extravasation; III = laceration >1 cm, no collecting-system injury; IV = through the collecting system (urinary extravasation) OR contained vascular injury; V = shattered kidney OR hilar avulsion / main-vessel injury or thrombosis.
Collecting-system involvement (urinary extravasation) defines grade IV — look for it on the delayed (excretory) CT phase.
Clinical cases
A 25-year-old falls from a height and has left flank pain and gross haematuria. He is haemodynamically stable after fluids. CT shows a deep parenchymal laceration with a moderate perinephric haematoma and no active contrast extravasation.
What is the appropriate management?