reply by authors

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bid conditions, such as hypertension, vascular diseaseand diabetes, which adversely affect the kidneys andlead to decreased preoperative eGFR, are clearly atincreased risk for lasting renal damage followingwarm ischemia.

The road to PN for small renal masses is in-creasingly well traveled as compelling data revealthe equivalency of PN and radical nephrectomy forcancer control, and the superiority of PN in termsof preserving renal function, preventing chronickidney disease and subsequent cardiovascularevents, and improving overall survival.1,2 Increas-ingly technical concerns relative to the PN tech-nique (open vs laparoscopic), ischemia time andtype (none, warm or cold), and careful case selec-tion are entering the PN conversation. This studytells us that for large tumors requiring complexlaparoscopic reconstruction leading to a WIT ofgreater than 40 minutes open PN with ice slushmay be a better choice for the patient. In addition,

REFERENCES

REPLY BY AUTHORS

taining similar oncological outcomes. Benefits in-

ated with worse overall survival,3 urologists canconsider a period of nonoperative active surveil-lance in such patients, particularly when the in-dex tumor is small.

Careful case selection, a stringent look at pre-operative cardiovascular and other comorbidities,routine calculation of eGFR using Web based for-mulas (www.mdrd.com) and a robust dialogue be-tween minimally invasive and open surgeons arenow essential components of an effective kidneysurgery team. In this way the delicate balancebetween local tumor control and maximum pres-ervation of renal function can be carefully main-tained.

Paul Russo

Urology ServiceDepartment of Surgery

Memorial Sloan Kettering Cancer CenterWeill Cornell College of Medicine

since preoperative CKD and low GFR are associ- New York, New York

1. Russo P and Huang W: The medical and oncolog-ical rationale for partial nephrectomy for treatmentof T1 renal cortical tumors. Urol Clin N Am 2008;

2. Huang W, Elkin E, Janga T, Levey A and Russo P:Partial Nephrectomy vs radical nephrectomy inpatients with small renal tumors: is there a differ-ence in mortality and cardiovascular outcomes?

Nonetheless, we rec

3. Pettus J, Jang T, Thompson HR, Yossepowitch O,Kagiwanda M and Russo P: Effect of baselineglomerular filtration rate on survival in patientsundergoing partial or radical nephrectomy for renal

J Urol 2009; 181: 55. cortical tumors. Mayo Clin Proc 2008; 83: 1101.

It is not clear that alteration in eGFR is entirely afunction of the operated kidney as the compensatoryability of the nonoperated kidney has an importantrole as well. Likewise the influence of insufflation,renal cooling and diuretics on preserving renal func-tion is more dogmatic than evidence-based. Onecommon emerging theme is that of the critical im-portance of renal preservation when treating a smallrenal mass.

Careful patient selection is necessary when opt-ing for LPN and one must always consider a periodof observation especially in older, sicker patientswith a small index lesion. The selection of appropri-ate candidates for LPN is entirely based on operatorskill set. At our institution the majority of PNs areperformed using laparoscopic and robotic tech-niques. In our hands, even complex PNs for centrallesions have a short ischemia time with LPN. Ourabsolute indications for open PN include a solitarykidney and documented significant renal insuffi-ciency for which avoidance of renal ischemia may bebeneficial.

Several large multicenter studies have indicatedmultiple benefits to LPN over open PN while main-

clude decreased hospital stay, decreased narcoticsuse, improved cosmesis, earlier resumption of diet,decreased surgical time and blood loss, and de-creased overall cost.1 These benefits need to beweighed against the potential for increased WIT.Recent technical advances have reduced WIT in thesetting of laparoscopic surgery and may allow ex-pansion of the indications for LPN to include morecomplex reconstructions. The Cleveland Clinic tech-nique for early unclamping has reduced WIT byhalf.2 The recent introduction of robotics has beenshown to facilitate management of complex hilarlesions and reduce WIT by almost 10 minutes com-pared to standard LPN.3,4

In our last 150 patients we have noted decreasingischemia time owing to the technical advances de-scribed. We now target a WIT of less than 20 minutesin most cases. We believe implementation of thesetechnique modifications (and potentially others in thefuture) will allow urologists to safely perform LPN inpatients for whom complex reconstruction is expected,while keeping WIT in an acceptable range. Thus, morepatients may experience the benefits of a minimallyinvasive approach without compromising outcomes.

ognize that at centers where few or

WARM ISCHEMIA TIME DURING NEPHRECTOMY AND GLOMERULAR FILTRATION RATE 2445

no LPNs are performed, open PN is an acceptablechoice and that the threshold for using this technique

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2008; 179: 627. Patel MN, Lipkin M et al: R

open surgeons to become facile in LPN will allow themost judicious use of open PN and increase the use of

would be lower. However, we believe that training PN at the national level.

1. Andonian S, Janetschek G and Lee BR: Laparo-scopic partial nephrectomy: an update on contem-porary issues. Urol Clin North Am 2008; 35: 385.

2. Nguyen MM and Gill IS: Halving ischemia timeduring laparoscopic partial nephrectomy. J Urol

3. Rogers CG, Metwalli A, Blatt AM, Bratslavsky G,Menon M, Linehan WM et al: Robotic partialnephrectomy for renal hilar tumors: a multi-insti-tutional analysis. J Urol 2008; 180: 2353.

4. Benway BM, Bhayani SB, Rogers CG, Dulabon LM,

nephrectomy versus laparoscopic partial ne-phrectomy for renal tumors: A multi-institutionalanalysis of perioperative outcomes. Unpublisheddata.