Percutaneous nephrolithotomy: position, position, position!

Percutaneous nephrolithotomy (PCNL) is the regular surgery for treating large or complex renal stones. Since its first inception, many variations have come in the approach including the modifications of patient position. The prone position is traditionally used, and subsequently, variations in prone and supine technique have been proposed and assessed over time. In an attempt to provide comprehensive information about the strategy applications of patient's position, the present review describes the position-related general basis, and provides a literature review of the pros and cons of various positions from a surgical and anaesthetic point of view. Latest evidence has shown the major advantages of supine PCNL compared with standard prone PCNL to be as follows: optimal cardiovascular and airway control; shorter operation time due to lack of the need for repositioning; opportunity for a combined retrograde approach. However, the prone position provides a broader surface area for percutaneous access; a wider space for manipulating the nephroscope and lithotripters; and opportunity for bilateral simultaneous PCNL. To overcome their respective limitations, various positioning modifications have been proposed. However, most reports are based on case series and/or have not obtained their results in a randomized controlled fashion and/or have not been analysed according to stone complexity and particular body status (e.g. obesity, etc.), thereby limiting the ability to make strong recommendations. One important caveat is that endourology training of supine PCNL would increase supine popularization, and the prone ureteroscopic technique would overcome the difficulty of endoscopic combined intrarenal surgery in the prone position. Thereby, adequate training in the different techniques for PCNL is important for optimizing the indications and treatment outcomes.