AUA 2023: Surgical Complications after Robotic Partial Nephrectomy

(UroToday.com) Alexander Kutikov lead a talk on the surgical complications associated with Robotic Partial Nephrectomy. He starts by highlighting a collaborative review he and I worked on for European Urology that walks through decision making for the management of localized solid renal masses – where a key decision point is the choice to treat the tumor, and at which point, we have to choose between radical nephrectomy, partial nephrectomy, and ablative options. Specifically today, he focuses on the choice to do a partial nephrectomy (PN).


He breaks down the 4 major categories of complications of PN (robotic):

  1. Vascular complications – hemorrhage, renal AV fistula/renal artery pseudoaneurysm
  2. Urine leak
  3. Injury to surrounding structures
  4. Non-RO resection – persistent surgical margins and local recurrence

Vascular Complications

He notes that the kidney is a very vascular organ – even though it is 1% of total body mass, it gets 25% of cardiac output and 1.2L blood flow per minute.

Vascular Complications: Hemorrhage/Bleeding

Bleeding after PN occurs in 1.6-8.6% of patients. The main cause is poorly controlled vasculature in the tumor resection bed. Risk factors include: large tumor size, endophytic tumor, increased intraoperative blood loss

Minimizing the risk of bleeding can be done by:

  • Meticulous dissection
  • Verification of complete hemostasis

Vascular Complications: Renal AV fistula/renal artery pseudoaneurysm

Renal AV Fistula is an abnormal connection between the intrarenal artery and venous circulation without a capillary bed. Occurs in 0.04-1.5% of patients. Renal Artery pseudoaneurysm is a collection of blood that forms outside the injured arterial wall but is contained within the renal parenchyma. Occurs in 0.4-2.3% of cases. The etiology of both is thought to be transection and failure to repair intrarenal arteriole during tumor resection and/or renorrhaphy.

Presentation is usually delayed (average is 14 days after surgery), with gross hematuria, flank pain, dizziness, fatigue, and anemia. Diagnosis requires high index of suspicion. If highly concerned, should warrant urgent percutaneous angiography (diagnostic and therapeutic). If uncertain, get CT Angiogram before percutaneous evaluation. Refractory cases may require repeat angioembolizations – or eventual nephrectomy.

Patients must be aware of the risk and report it immediately.

Urinary Leaks after PN
Urine leak rates vary with the approach

  • Open: 1.0-17.4%
  • Laparoscopic: 1.6-16.5%
  • Robotic: 0.6-3.0%

Risk factors include tumor size, tumor anatomic complexity, renal pelvis anatomy, ischemia time, blood loss, operative time, tumor location, CKD stage, surgeon experience, and repair complexity:

  • The intrarenal pelvis may be associated with increased chance of a urine leak, especially as tumor complexity increases

He notes that drains can be safely omitted – they don’t prevent leaks, and in some cases, may make it more likely. Therefore, detection is usually with clinical presentation – imaging, fluid analysis, rising sCr, and clinical presentation (fevers/chills, flank pain). Typically it presents about 13 days post-op (range 3-32). Management usually involves percutaneous drain, nephroureteral stent +/- foley catheter draining, rare cases require reoperation

Injury to Surrounding Structures
Potential injuries and reported rates include:

  • Bowel (0.3-0.5%)
  • Pleural Injury (0.6-12.9%)
  • Splenic Injury (0.5-4.3%)
  • Hepatobiliary Injury (0.1-1.4%)
  • Pancreatic (0.2-2.1%)
  • Lymphatic (0.8-5.1%)

Non R0 resection – A complication to be avoided!

Positive surgical margins refers to cancer cells extending to the inked surface of resected primary tumor specimens. Occur in 1.1-10.7% of cases. Risk factors: tumors close to hilum, higher stage tumor, larger tumor size, surgeon inexperience Every effort should be made to obtain negative surgical margins during PN but, in case it does happen, most patients can be managed with close surveillance – repeat PN or radical nephrectomy should be used carefully and rarely.

Conclusions:
  • Balance oncologic control with minimized risks and complications.
  • Ensure proper pre-operative risk stratification and patient selection.
  • Embrace the opportunity to learn from complications to refine surgical technique and improve outcomes

Presented by: Alexander Kutikov, MD, FACS, Fox Chase Cancer Center, Philadelphia, PA

Written by: Thenappan (Thenu) Chandrasekar, MD – Urologic Oncologist, Associate Professor of Urology, University of California, Davis @tchandra_uromd @UCDavisUrology on Twitter during the 2023 American Urological Association (AUA) Annual Meeting, Chicago, IL, April 27 – May 1, 2023

Reference:

  1. Chandrasekar T, Boorjian SA, Capitanio U, Gershman B, Mir MC, Kutikov A. Collaborative Review: Factors Influencing Treatment Decisions for Patients with a Localized Solid Renal Mass. Eur Urol. 2021 Nov;80(5):575-588. doi: 10.1016/j.eururo.2021.01.021. Epub 2021 Feb 6. PMID: 33558091.