Ambulatory percutaneous nephrolithotomy for staghorn calculi: a systematic review

INTRODUCTION: Percutaneous nephrolithotomy (PCNL) is the gold standard in managing staghorn calculi. There is an increasing trend towards performing PCNL as an ambulatory procedure for its safe outcomes, patient satisfaction and cost benefits. However, there has not been a standard consensus on how to safely expand the criteria for ambulatory PCNL (aPCNL) to more complex cases, including staghorn patients.EVIDENCE ACQUISITION: A systematic review was performed to review the outcomes of aPCNL for staghorn patients. Literature search was conducted on four databases (Medline, Embase, Web of Science and Cochrane Central) using synonyms of “PCNL” and “ambulatory” as search terms. Full text of papers that reported data on aPCNL were screened and were included if outcomes specific to staghorn cases were reported. Characteristics and outcomes of staghorn patients were extracted and analysed.EVIDENCE SYNTHESIS: From the 20 included papers, a total of 3927 patients underwent aPCNL, of which 797 (20.3%) were staghorn patients, ranging from 8.1% to 94.7% within each study. These patients required longer operating time and had lower stone-free rates. However, one study that reported logistic regression modelling of staghorn did not find it a significant predictor of residual stone. Staghorn patients also had a higher readmission rate, mostly infection-related, and a higher postoperative complication rate, although these were mostly of Clavien-Dindo I and II. In one study, staghorn calculus was found to be a significant predictor of hospital transfer.CONCLUSIONS: Staghorn patients are often managed ambulatorily. At present, staghorn-specific outcome data of aPCNL is encouraging but limited. Most available data show that it can be performed with comparable safety outcomes to both inpatient PCNL for staghorn and aPCNL for non-staghorn. Further studies are needed to evaluate if staghorn calculi could be safely and routinely managed with aPCNL.