Using the Modified Clavien Grading System to Classify Complications of Percutaneous Nephrolithotomy

A modified Clavien classification system has been proposed to grade perioperative complications. We share our experience in grading the complications of percutaneous nephrolithotomy (PNL), according to this new classification.

A total of 809 PNLs performed between 2010 and 2014 were reviewed retrospectively. The modified Clavien classification system, which classifies the perioperative complications into 5 grades, was applied. Grade wise comparison of complications between the patients with simple and complex calculi was done. We also carried out a univariate analysis of different predictors of complications after surgery.

A total of 253 perioperative complications were observed in 237 (29.29%) patients. Most complications were related to bleeding and urinary leakage. Patients with complex calculi had significantly more number of complications across all Clavien groups. In a univariate analysis, positive preoperative urine culture and multiple access for stone clearance were identified to be the independent predictors of complications.

The modified Clavien system is a simplistic grading system for classification of postoperative complications. However, it suffers from various shortcomings. Therefore, till the proposition of a more comprehensive classification system, the modified Clavien system is useful for reporting the complications and short-term outcomes of PNL.