Recently, the possibility of avoiding nephrostomy tube placement has become real, with the alternative of eliminating it altogether. In fact, the absolute need for postoperative renal drainage after PNL has been definitely questioned and challenged in recent years:

The description of a conventional PNL without the final application of a nephrostomy tube was first published in 1997 by Bellman and coworkers and has now been accepted as a safe and effective alternative. In both standard [14, 19] and miniaturized PNL [20–22], the tubeless procedure is in any case a stented PNL. In fact, alternative ureteral drainage to prevent urine leakage through the percutaneous tract is provided by the retrograde application of a ureteral catheter or a double-J stent with external string for few days (reducing costs and stent-related morbidity and avoiding endoscopic procedure for its removal) or the placement of a double-J stent for longer periods (one or more weeks, depending upon postoperative stone clearance status, with sometimes significant stent-related symptoms and the need for a postoperative cystoscopy for its removal).

The true totally tubeless PNL (tubeless and stentless), proposed by Wickham and colleagues almost 30 years ago, has no postoperative drainage of the operated collecting system at all and may be put into practice with success in very selected cases [23–25].

Randomized studies, carried out mainly with the patient in prone position [13, 26] and only in a couple of studies in the supine position [27, 28], demonstrated that tubeless procedures imply:

A tubeless procedure seems feasible with reduced postoperative morbidity even in particular cases, including large stone burdens, children, elderly, obese patients, after previous ipsilateral open surgery, patients with a solitary kidney, horseshoe or ectopic pelvic kidneys, raised serum creatinine levels, on antiplatelet therapy or cirrhotic patients, and bilateral synchronous PNL [19, 29–37].

Various authors [2, 13, 37] suggested a number of inclusion criteria for tubeless procedures, from which we can argue that one universal solution is not applicable for all patients undergoing PNL and that the optimal renal drainage method should be individualized, depending upon patient features, operative course, procedural complexity, stone burden:

There is no general consensus about the wisdom of tubeless PNL. Some authors demonstrated equivalent results with early removal of small-bore nephrostomy tubes, anywhere carried out from 1 to 2 days postoperatively and in any case before the patient is discharged home [38, 39].

The European Association of Urology guidelines suggest: in uncomplicated cases tubeless PNL, with or without application of a sealant or double-J stenting (LE 1b, grade of recommendation A); in complicated cases or when a second intervention is necessary a standard PNL with a nephrostomy tube in place.

Alternative or innovative techniques to establish hemostasis of the tubeless access tract have been reported, from the simple mechanical compression of the percutaneous tract for few minutes at the end of the procedure [7] to the application of deep fascial stitches [40] and from the cryoablation of the tract with a single 10-min freeze-thaw cycle to −20 °C, in which the cryoprobe traverses the nephrostomy tract [38], to its monopolar or bipolar cauterization using a blunt electrocautery loop mounted on a 26F resectoscope [41, 42]. The last frontier is the application of absorbable hemostatic agents (including Surgicel from Ethicon, a blood clot-inducing material made up of oxidized cellulose polymers), with the additional aim to prevent urine leakage [37, 43–45].

Absorbable hemostatic agents include:

Fibrin glues are expensive and their use raised concerns for a possible lithogenic effect. According to experimental studies in a porcine model, hemostatic gelatin matrix was found to be the most optimal because it remains in fine particulate suspension in urine, whereas fibrin maintains a semisolid gelatinous state and may persist in the tract for up to 30 days, thus inhibiting wound healing [46–50].