Comparison of Tissue Oxygenation Profiles Using 3 Different Methods of Vascular Control During Porcine Partial Nephrectomy
Received 26 March 2009; accepted 11 May 2009. published online 22 July 2009.
Objectives
To compare oxygenation profiles and renal function outcomes between 3 methods of vascular control during porcine partial nephrectomy.
Methods
To create a solitary kidney model, 18 pigs were subjected to a laparoscopic nephrectomy. Following a 7-day recovery, a contralateral open partial nephrectomy was performed with vascular control by either total renal artery clamping (TRAC, n = 6), partial renal artery clamping (PRAC, n = 6), or selective renal parenchymal clamping (SRPC, n = 6). Renal partial oxygen pressure (rPO2) was monitored using a Licox probe. Serum creatinine was assessed on day 0 and postoperative days 3 and 7. Pigs were sacrificed on the seventh day and the kidney sent for pathological examination.
Results
Intraoperative oxygenation profiles demonstrated a lower percentage decline (P = .01), longer interval to nadir (P = .04), improved percentage recovery of baseline rPO2 (P = .04), and a shorter duration to recover baseline rPO2 (P = .03) in the PRAC and SRPC groups than in the TRAC. Despite not occluding the renal vasculature, the SRPC group experienced declines in rPO2 profiles of almost 50% from baseline. Serum creatinine levels increased significantly more in the TRAC group at days 3 and 7 (P = .04 and .01, respectively). Histological examination demonstrated patchy inflammation of parenchyma in all groups.
Conclusions
The rPO2 monitoring may provide a novel means to allow real-time assessment and titration of kidney perfusion during partial nephrectomy. PRAC and SRPC demonstrate favorable renal oxygenation profiles compared with TRAC. Interestingly, SRPC kidneys experienced a significant decline in tissue oxygenation profiles. Further work is necessary to better delineate the mechanism underlying this decline.
aDivision of Urology, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania
bDepartment of Urology, University of Texas Southwestern Medical Center, Dallas, Texas
cDepartment of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
Reprint requests: Jay D. Raman, M.D., Division of Urology, Penn State Milton S. Hershey Medical Center, 500 University Drive, C4830B, Hershey, PA 17033
Karim Bensalah is supported by the Association Française d'urologie.
ABSTRACT