What are the surgical steps for a partial nephrectomy?

Surgical Steps for Partial Nephrectomy

The standard surgical steps for partial nephrectomy include patient positioning, tumor exposure, hilar control, tumor excision, collecting system repair, parenchymal reconstruction, and closure, with the goal of optimal tumor control while minimizing ischemia time to less than 30 minutes. 1

Approach Selection

• Partial nephrectomy can be performed via open, laparoscopic, or robot-assisted approaches, with comparable oncologic outcomes in experienced hands 1
• Transperitoneal approach is preferred for anterior or lateral tumors (97% of anterior tumors are managed this way) due to larger working space and better angles for intracorporeal reconstruction 1
• Retroperitoneal approach is preferred for posterior tumors (77% of posterior tumors are managed this way), particularly posteromedial lesions 1
• Robot-assisted partial nephrectomy provides equivalent perioperative outcomes to laparoscopic partial nephrectomy but with significantly shorter warm ischemia time 1, 2

Preoperative Preparation

• Tumor complexity assessment using nephrometry scoring systems (R.E.N.A.L., PADUA) to guide surgical approach 2
• 3D imaging for mapping vascular anatomy and planning resection strategy, especially for central tumors 2

Surgical Steps

1. Patient Positioning and Access

• Position patient based on approach (flank position for open/retroperitoneal; modified flank or supine for transperitoneal) 1
• Establish access (incision for open; port placement for laparoscopic/robotic) 1

2. Tumor Exposure

• Mobilize kidney and identify tumor location 1
• Preserve perirenal fat over tumor for pathological examination 1
• Use intraoperative ultrasound to confirm tumor margins if needed 3

3. Hilar Control

• Identify and isolate renal vessels 1
• For transperitoneal approach: typically en bloc hilar control with a Satinsky clamp 1
• For retroperitoneal approach: individual vessel control with bulldog clamps 1
• Apply vascular clamps to achieve warm ischemia (aim to keep under 30 minutes) 1, 2

4. Tumor Excision

• Mark resection margin with electrocautery, ensuring a minimal tumor-free surgical margin 1
• Excise tumor with cold-cut using scissors, leaving a thin rim of normal parenchyma around tumor 1, 3
• Options include simple enucleation (sparing healthy parenchyma), enucleoresection (removing thin layer of healthy tissue), or wedge resection (wider excision) 1

5. Collecting System Repair

• Identify any collecting system entry 1
• Repair with running 2-zero polyglactin suture on a CT-1 needle 1
• Consider injection of methylene blue to identify collecting system leaks 3

6. Parenchymal Reconstruction

• Achieve hemostasis of larger transected vessels 1
• Perform renal parenchymal reconstruction using a modified pledget clip technique 1:
  • Prepare a 9-inch No. 0 polyglactin suture with a knot 2-3 inches from end
  • Place a Hem-o-lok clip proximal to the knot
  • Pass suture through renal parenchyma on one side of defect
  • Place oxidized cellulose bolster in the partial nephrectomy bed
  • Pass suture through other side of defect
  • Tighten with second Hem-o-lok clip
  • Tie free ends of suture over bolster
  • Place 3-4 similar parenchymal stitches across defect 1

7. Closure and Drainage

• Place perirenal drain if collecting system was entered 1
• Remove ureteral and Foley catheters on postoperative day 2 1
• Maintain perirenal drain for at least 5 days and remove when output is less than 50cc daily for 3 consecutive days 1

Complications and Management

• Most common complications include hemorrhage (10%), urinary fistula (<5%), and perirenal hematoma 1, 4
• Risk factors for complications include tumor size, inflammation of perirenal fat, surgical approach, surgeon experience, center volume, patient comorbidities, and age 4
• Careful patient selection and surgical planning can minimize complications 4

Postoperative Care

• Monitor for hematuria, perirenal hematoma, and urinary fistulas 1
• Follow-up at 1 month with physical examination, serum creatinine measurement, and radionuclide renal scan 1
• Maintain routine oncological surveillance thereafter 1

Technical Considerations

• Warm ischemia time should ideally be kept under 30 minutes to preserve renal function 1, 2
• Surgeon experience significantly impacts outcomes, particularly for complex tumors 2
• For extremely complex tumors not amenable to minimally invasive approaches, open partial nephrectomy may be preferred 2