Indications, techniques, outcomes, and limitations for minimally ischemic and off-clamp partial nephrectomy: a systematic review of the literature.
BACKGROUND
On-clamp partial nephrectomy (PN) has been considered the standard approach to minimize intraoperative bleeding and thus achieve adequate control of tumor margins. The potential negative impact of ischemia on renal function (RF) led to the development of techniques to minimize or avoid renal ischemia, such as off-clamp PN and minimally ischemic PN techniques.


OBJECTIVE
To review current evidence on the indications and techniques for and outcomes of minimally ischemic and off-clamp PN.


METHODS
A systematic review of English-language publications on PN without a main renal artery clamp from January 2005 to July 2014 was performed using the Medline, Embase, and Web of Science databases.


RESULTS
The searches retrieved 52 papers. Off-clamp PN has been more commonly applied to small and peripheral renal tumors, while minimally ischemic PN is best suited for hilar and medially located renal tumors. These approaches are associated with increased intraoperative blood loss and perioperative transfusion rates compared to on-clamp PN. Minimally ischemic and off-clamp PN have potential functional benefits when longer ischemia time is anticipated, particularly for patients with lower baseline RF. Limitations include the lack of prospective randomized trials comparing minimally ischemic and off-clamp to on-clamp techniques, and the small sample size and short follow-up of most published series. The impact of different resection and renorrhaphy techniques on postoperative RF and its assessment via renal scintigraphy requires further investigations.


CONCLUSIONS
Minimally ischemic and off-clamp PN are established procedures that may be particularly applicable for patients with decreased baseline RF. However, these techniques are technically demanding, with potential for increased blood loss, and require considerable experience with PN surgery. The role of ischemia in patients with a contralateral healthy kidney and consequently an indication for elective minimally ischemic or off-clamp PN remains a debatable issue.


RESULTS
In this review we analyzed available evidence on minimally ischemic and off-clamp partial nephrectomy. These techniques, although technically demanding, may be particularly applicable for patients with decreased baseline renal function.
Department of Urology, "Regina Elena" National Cancer Institute, Rome, Italy; Department of Urology, San Giovanni Bosco Hospital, Turin, Italy. Electronic address: puldet@gmail.com.
Giuseppe
G
Simone
USC Institute of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
Inderbir S
IS
Gill
OLV Vattikuti Robotic Surgery Institute, Aalst, Belgium.
Alexandre
A
Mottrie
Division of Urologic Oncology, Fox Chase Cancer Center, Temple University Health System, Philadelphia, PA, USA.
Alexander
A
Kutikov
Department of Urology, Bicêtre Hospital, Paris XI University, Le Kremlin-Bicêtre, France.
Jean-Jacques
JJ
Patard
Department of Urology, Hospital Clínic i Provincial de Barcelona, Barcelona, Spain.
Antonio
A
Alcaraz
Vattikuti Urology Institute, Henry Ford Hospital, Detroit, MI, USA.
Craig G
CG
Rogers
D016063:Blood Loss, Surgical / Q000517:prevention & control*; D003250:Constriction; D004621:Embolization, Therapeutic / Q000009:adverse effects; D006801:Humans; D007511:Ischemia; D007680:Kidney Neoplasms / Q000098:blood supply / Q000473:pathology / Q000601:surgery*; D009392:Nephrectomy / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D012077:Renal Artery / Q000503:physiopathology / Q000601:surgery*; D012079:Renal Circulation; D012307:Risk Factors; D016896:Treatment Outcome
Clampless; Ischemia; Off-clamp; Parenchymal clamp; Partial nephrectomy; Segmental clamp; Selective clamp; Unclamped; Zero-ischemia