Category: Epidemiology, Health Policy, Socioeconomics & Outcomes

MP28-4 - An Unusual Risk Factor Influencing Hospital Readmission Following Percutaneous Nephrolithotomy

Sun, Sep 23
10:00 AM - 12:00 PM

Introduction & Objective :

Several risk factors have been shown to influence unexpected hospital return (UR) and rehospitalization (RH) rates after percutaneous nephrolithotomy (PCNL). Most would be fairly intuitive, including the presence of complex stones, stone size and early postoperative complications. In most studies, readmissions in the first 30 days after surgery are described; we aimed to analyze the UR and RH rates and risk factors in a longer period, during the first 90 days.


Methods :

We performed an exploratory cross-sectional study selecting all patients subjected to PCNL from January 2008 to March 2017. We analyzed demographics, stone size and complexity, selective renal function of the operated kidney, duration of surgery, stone-free status, hospitalization length, and perioperative complications. All these factors were tested for UR and RH status in the first 3 months after surgery, as well as number of readmissions, number of rehospitalization days and the need for invasive or minimally invasive procedures.


Results :

127 patients with mean age of 52,65 years and 60,6% female were analyzed. Most patients had staghorn calculi (66%) with an average size (of the largest stone) of 36,4mm. There was an average duration of surgery of 150 minutes. Significant complications (Clavien > 2) in the perioperative period were found in 6,3% of patients; 1 patient died due to sepsis. In the first 90 days following surgery, there was a 28,3% rate of UR, with 16,5% of patients requiring RH; most of these were caused by urinary tract infection or upper tract obstruction. Patients with tubeless procedures had significantly less UR rates, although no difference was found in RH or need for intervention. Through logistic regression, a higher selective function of the affected kidney (as measured by renal scintigraphy) was found to significantly influence (through an increase in) the rates of UR, RH and the need for further treatment procedures. It also correlated with the absolute number of unplanned visits and the total number of days in RH.


Conclusions :

To our knowledge, the findings of a correlation between higher selective renal function of affected kidney and UR / RH rates was not previously described. Although the pathophysiological mechanism at play is not immediately apparent, higher vascularization and urine production in these kidneys could account for these findings. Percutaneous access is probably easier and less hemorrhagic in kidneys with more hydronephrosis and less renal parenchyma. Pain perception in differently functioning kidneys is also not described in studies done so far, and if altered could provide some answers to the questions raised by these findings.

Miguel Eliseu

Urology Resident
Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Vera Marques

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Hugo Antunes

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Edgar Tavares-Da-Silva

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Pedro Simões

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Pedro Moreira

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Paulo Temido

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal

Arnaldo Figueiredo

Coimbra Hospital and University Centre
Coimbra, Coimbra, Portugal