Vacuum-assisted mini-percutaneous nephrolithotomy: a new perspective in fragments clearance and intrarenal pressure control

Abstract

Purpose To describe the vacuum-assisted mini-percutaneous nephrolithotomy (vmPCNL) technique performed via the 16Ch ClearPetra sheath, to evaluate its outcomes and to analyze intrarenal pressure (IRP) fluctuations during surgery. Methods Data from all consecutive vmPCNL procedures from September 2017 to October 2019 were prospectively collected. Data included patients' and stones characteristics, intra and peri-operative items, post-operative complications and stone clearance. Patients undergoing vmPCNL from March to October 2019 were submitted to IRP measurement during surgery. Results A total of 122 vmPCNL procedures were performed. Median stone volume was 1.92 cm 3. Median operative time was 90 min and median lithotripsy and lapaxy time was 28 min. Stone clearance rate was 71.3%. Thirty-one (25.2%) patients experienced post-operative complications, seven of which were Clavien 3. Postoperative fever occurred in nine (7.4%) patients and one (0.8%) needed a transfusion. No sepsis were observed. IRPs were measured in 22 procedures. Mean IRP was 15.3 cmH 2 O and median accumulative time with IRP > 40.78 cmH 2 O (pyelovenous backflow threshold) was 28.52 sec. Maximum IRP peaks were reached during the surgical steps when aspiration is closed (mainly pyelograms), whereas during lithotripsy and suction-mediated lapaxy, the threshold of 40.78 cmH 2 O was overcome in three procedures. Conclusions vmPCNL is a safe procedure with satisfactory stone clearance rates. Mean IRP was always lower than the threshold of pyelo-venous backflow and the accumulative time with IRP over this limit was short in most of the procedures. During lithotripsy and vacuum-mediated lapaxy, IRP rarely raised over the threshold.

Cost analysis between mini-percutaneous nephrolithotomy with and without vacuum-assisted access sheath

“…Moreover, shorter OT may help limiting infectious complication by reducing the time span during which surgery is performed at elevated intra-pelvic pressure. Aspiration-assisted mPCNL techniques have already been proved to be associated with less bleeding [ 10 , 23 ], lower renal pelvic pressures and subsequent infectious complications [ 6 , 12 , 14 , 24 ] than non-suctioning miniPCNL procedures. In this series we confirmed that infectious complications were lower for vmPCNL than MIP.…”

“…However, several Authors have proposed the use of various PCNL sheaths or nephroscopes equipped with suctioning mechanisms with promising outcomes [8][9][10][11]. Among the new instruments, the vacuum-assisted mini PCNL (vmPCNL) is a safe and effective treatment option for kidney stones [12,13]. Previous Authors have shown that vmPCNL was associated with shorter OT, reduced use of accessory devices for stone removal and lower intra-pelvic pressures than mini-PCNL, thanks to its continuous aspiration system that allows for simultaneous lithotripsy and litholapaxy [13,14].…”

Is There Still a Place for Percutaneous Nephrolithotomy in Current Times?

“…However, smaller instruments carry some limitations too, such as a reduced choice of lithotripsy and lapaxy probes, difficulties in fragment retrieval, longer operation time, reduced visual field, and higher intra renal pressure (IRP) [ 16 ]. In order to overcome these limitations, aspiration-integrated mini-PCNL systems have been developed in recent years, such as the Super Mini PCNL (SMP) and the vacuum-assisted mini-PCNL performed by means of the Clear Petra system [ 17 ].…”

Double-Sheath Vacuum Suction Minimally Invasive Percutaneous Nephrolithotomy for Management of Large Renal Stones

“…However, mini-PCNL presents several shortcomings such as difficult stone fragment extraction, extended operative time, and elevated renal pelvic pressure [1, [10][11][12]. Previous studies have reported that the vacuum-assisted sheath DOI: 10.1159/000518259 (ClearPetra; Well Lead Medical) in mini-PCNL allows the surgeon to obtain very good control over renal pelvic pressure [13][14][15]. Nevertheless, the inflow and outflow occur in the same cavity of this vacuum-assisted sheath.…”