OBJECTIVES: The objective of this study was to compare costs and resource utilization in renal surgery patients with perioperative blood loss (PBL) to those who did not experience perioperative blood loss (NPBL). METHODS: Inpatient discharges for renal surgery (ICD-9-CM:55.0X, 55.1X, 55.24, 55.3X-55.8X) were identified from the Premier Perspective® Database (CY 2009-Q2 of CY 2010). Discharges were categorized as PBL group if they had received at least one blood transfusion (ICD-9-CM:99.02-99.07; CPT:36430, 35455) during the hospital stay, otherwise were included in the NPBL group. Blood transfusion was assumed to be an indicator for PBL. Groups were matched (1:1) on age, gender, race, CCI score, APR-DRG severity and elective admission type using propensity score. Adjusted estimates for costs (total and departmental), days of stay in hospital (LOS), ICU, and operating room (OR) time in minutes were compared between PBL and NPBL groups using generalized linear model (GLM) with gamma distribution and log link. RESULTS: A total of 27,573 renal surgery discharges were identified. 4,885 (17.7%) of all the selected patients required at least one blood transfusion perioperatively. After matching, 4,699 discharges were retained in each group for the final analysis. Adjusted mean total cost were significantly higher for the PBL group compared to NPBL group ($48,583 vs. $35,298, p<0.0001). Mean adjusted costs associated with room & board, central supply, surgery, pharmacy and laboratory and pathology between PBL and NPBL group and were also significantly higher for PBL group (all p<0.05). Compared to NPBL group, PBL group had higher mean LOS (10.5 days vs. 7.9 days) and ICU days (4.5 days vs. 3.6 days) and had longer OR time (227 minutes vs. 194 minutes) (all p<0.0001). CONCLUSIONS: Perioperative blood loss for renal surgery patients adds significant burden to hospital costs and resources. Adopting strategies aimed at minimizing perioperative blood loss during renal surgeries may be helpful.