Introduction. An important aspect of the prevention of complications in percutaneous nephrolithotomy (PCNL) is to reduce the likelihood of injury to the adjacent structures and perirenal tissues.
Aim. To determine the efficiency and safety of renal puncture during mini-PCNL with a new atraumatic needle MG.
Materials and methods. A total of 67 patients who underwent mini-percutaneous nephrolithotomy at the Institute of Urology and Human Reproductive Health of Sechenov University were included in the prospective study. For the purpose of homogeneity of the groups, those with staghorn nephrolithiasis, nephrostomy, a history of prior kidney surgery (including PCNL), renal and collecting system anomalies, acute pyelonephritis, and blood clotting disorders were not included. The main group consisted of 34 (50.7%) patients who underwent atraumatic kidney puncture with a new needle MG (MIT, Russia), while in the control group there were 33 (49.3%) patients, who underwent standard puncture with Chiba or Troakar needles (Coloplast A/S, Denmark). The outer diameter of all needles was 18 G.
Results. In patients with a standard access, a hemoglobin decrease in the early postoperative period was more pronounced (p=0.024). The incidence of complications according to the Clavien-Dindo classification did not differ significantly (p=0.351), however, a JJ stent was placed in two patients from the control group due to impaired urine flow and the development of urinoma.
Conclusion. Together with a similar stone-free rate, atraumatic needle allows to reduce a hemoglobin drop, as well as less development of severe complications.

Keywords: complications of percutaneous nephrolithotomy, kidney puncture, mini-percutaneous nephrolithotomy, urolithiasis