Study Proponents RCT Design Population Conclusion Limitations Is Ischemia a Primary Predictor of Renal Function?
Lane et al. [4] No Prospective Comparative Study 660 With short intervals ischemia is not a predictor of renal function 1.Retrospective 2.Subjective estimate of preserved parenchyma 3.Missing data No; WIT is not an independent factor predicting renal function
Spana et al. [5] No Retrospective 450 Most complications are Clavien I and II No objective renal mass scoring used resulting in difficulty correlating WIT and complications No; At an average of 20 (Range 0‐83) minutes WIT only had 1ARF (2%)
Bhayani et al. [6] No Retrospective 118 Based on post‐op Crea, WIT of up to 55 mins does not influence long term Renal function 1. All patients had Normal contralateral kidney, normal Creatinine may be due to their compensation No; WIT does not significantly alter long term Renal function
Papalia et al. [7] No Prospective 60 Controlled hypotension allowed LPN and RPN to be done without clamping 1. It assumed warm ischemia Is harmful 2. Median Controlled Hypotension time is 14 minutes Yes; WIT is assumed as a predictor af ultimate Renal function
Gill et al. [8] No Prospective 58 Global surgical Ischemia can be avoided by anatomical vascular microdissection 1.Mean follow‐ up 3 mos. Short‐ term functional outcomes only. 2.Small population Yes; Extrapolated based on collective experience with >800 patients
Porpiglia et al. [9] No Prospective 54 WIT contributes To irreversible damage observed at 3 mos but does not worsen After 4 years of follow--‐up Data it concluded That only limited injury can be caused By 27.8 mins of WIT. No Correlation with hypertension development And post‐ ischemic renal failure Yes; Multivariable analysis shows WIT is an independent predictor of SRF and ERPF baseline weighted differential changes at 3 months post‐op
Bollens et al. [10] No Retrospective 39 Extracorporeal clamping significantly decreases WIT No explanation for 2 patients having significant Renal impairment Yes
Funahashi etal.[11] No Prospective 32 WIT>25 mins causes irreversible Diffuse damage 1. Non‐use of ACS to classify tumor complexity 2. It did not account for Amount of tissue resected 3. Suture width Yes; WIT>25 mins Causes irreversible Diffuse parenchymal damage
Holzer et al. [12] No Prospective 21 HSI is a real time non-invasive renal Oxygenation monitoring. Renal oxygenation Reaches a nadir 10 mins after clamping Unidentified confounding Variable causing renal Reoxygenation despite complete occlusion Yes it assumed WIT is a factor In determining Post treatment Renal function, showcases a novel way of monitoring ischemia
Gill et al. [13] No Prospective 15 Promising initial Results (hence Study was continued) 1. Not for all patients. 2. Not applicable to all surgeons Yes it assumed WIT is afactor In determining post‐op renal function
Raman et al. [14] No Animal Experimental 18 Pigs PRAC and SRPC demonstrate Better oxygenation Profiles than TRAC. SRPC kidneys Demonstrated a Decline in oxygenation profiles No actual Tumor to take into account. Yes; Assumes WIT Is a factor In determining Post ‐op renal Function showcases A novel way Of monitoring ischemia
Baldwin et al. [15] Yes Animal Experimental 16 Pigs Renal ischemic Times up to 90 Minutes were well Tolerated by Solitary porcine kidneys. Ischemic preconditioning No; WIT is not An independent Factor predicting renalfunction
Best et al. [16] No Animal Experimental 14 Pigs Incomplete RA occlusion Incomplete RA occlusion during Porcine PN Resulted in favorable Renal oxygenation Profiles with as little as10% BF, renoprotective at 25% of baseline 1Small population
2. Imperfect human translation Due to unique porcine characteristics
Yes; Assumes WIT is A factor in determining post‐op renal function, showcases a novel way of monitoring ischemia
Parekh D. [17] No Editorial NA In majority of pts Tumor resection Can be accomplished Safely without Impacting on renal function No power No; WIT does not significantly alter long term renal function
Gill and Campbell [18] No Editorial NA Presents opposing views No power Equivocal
Abbreviation: WIT – Warm Ischemia Time, LPN – Laparascopic Partial Nephrectomy, RPN: Robotic Partial Nephroctomy, SRF: Split Renal Function, ERPF: Effective Renal Plasma Flow, CKD: Chronic Kidney Diseas, HIS- Hyperspectral Imaging, TRAC- Total Renal Artery Occlusion, PRAC- Partial Renal Artery Occlusion, SRPC: Selective Renal Parenchymal Clamping, ACS-Anatomic Classification System, RCT- Randomized Controlled Trial
Table 1: lists the 15 articles included in this review and includes a brief description of their research design, conclusions and study limitation.