Comparison of warm and cold ischemia on renal function after partial nephrectomy.

Area of Science:

• Nephrology
• Urology
• Nuclear Medicine

Background:

• Partial nephrectomy is a common procedure for kidney tumors.
• Ischemic injury to the kidney remnant is a potential complication.
• Assessing renal function post-surgery is crucial for patient outcomes.

Purpose of the Study:

• To evaluate the impact of warm versus cold ischemia on renal function after partial nephrectomy.
• To utilize (99m)Tc-mercaptoacetyltriglycine ((99m)Tc-MAG3) renal scintigraphy to quantify ischemic damage.
• To correlate ischemic time with functional changes in the operated kidney.

Main Methods:

• A comparative study involving 59 patients with warm ischemia and 64 with cold ischemia during open partial nephrectomy.
• (99m)Tc-MAG3 renal scintigraphy was performed to assess split renal function via effective renal plasma flow.
• Regional (99m)Tc-MAG3 uptake in unaffected kidney areas was analyzed to detect ischemic damage.

Main Results:

• Effective renal plasma flow decreased significantly more in the warm ischemia group (33.8% reduction) compared to the cold ischemia group (22.6% reduction) one week post-surgery.
• Regional (99m)Tc-MAG3 uptake showed a decrease in the warm ischemia group (10.8%) but remained stable in the cold ischemia group (1.5% increase) at baseline.
• Prolonged warm ischemia (≥ 25 minutes) led to persistent regional uptake reduction at 6 months, correlating significantly with ischemic time, unlike in the cold ischemia group.

Conclusions:

• Warm ischemia exceeding 25 minutes results in long-lasting, diffuse renal damage.
• Cold ischemia effectively preserves renal remnant function, preventing injury even with prolonged application (up to 58 minutes).
• (99m)Tc-MAG3 scintigraphy is a valuable tool for assessing renal functional changes and ischemic injury after partial nephrectomy.