Renal Insufficiency is an Independent Risk Factor for Complications After Partial Nephrectomy

Purpose

We identify and describe the postoperative outcomes of a single surgeon partial nephrectomy cohort. We performed univariate and multivariate analysis on preoperative patient characteristics, and their association with increased length of stay and postoperative complication rates.

Materials and Methods

Perioperative characteristics of 146 consecutive patients undergoing partial nephrectomy were recorded. Postoperative complications were defined as those occurring within 30 days using the Clavien postoperative complication scale. We conducted logistic regression analysis to evaluate the development of complications and linear regression analysis to determine the effect on length of stay.

Results

In a linear regression model patients with renal insufficiency had a mean of 1.7 ± 0.6 days longer length of stay compared to those with normal renal function (p = 0.006). Complications occurred in 48.5% in the renal insufficiency group compared with 16.8% in the other cohort (p = 0.0004). There were no mortalities. On univariable analysis 4 factors were significantly associated with the development of complications including race (p = 0.03), preoperative Modification of Diet in Renal Disease less than 60 (p <0.0001), tumor size greater than 4 cm (p = 0.03) and estimated blood loss (p = 0.04). On multivariable analysis the 2 factors of Modification of Diet in Renal Disease less than 60 (p = 0.003) and race (p = 0.03) remained significant. The odds ratio for complications comparing patients with renal insufficiency to the normal cohort, adjusting for confounding factors, was 4.58 (95% CI 1.65–12.65).

Conclusions

Preoperative renal insufficiency defined as Modification of Diet in Renal Disease less than 60 and nonAfrican-American race, which may be related to Modification of Diet in Renal Disease, are predictive of complications after partial nephrectomy. Decreased Modification of Diet in Renal Disease is an independent risk factor for increased length of hospital stay and increased complication rate in partial nephrectomy.

Key Words: carcinoma, renal cell, nephrectomy, complications, laparoscopy, multivariate analysis

Abbreviations and Acronyms: BMI, body mass index, CCS, Charlson comorbidity score, CKD, chronic kidney disease, DM, diabetes mellitus, EBL, estimated blood loss, GFR, glomerular filtration rate, HTN, hypertension, LOS, length of stay, LPN, laparoscopic partial nephrectomy, MDRD, Modification of Diet in Renal Disease, NSS, nephron sparing surgery, OPN, open partial nephrectomy, RCC, renal cell carcinoma