Modified supine versus prone position in percutaneous nephrolithotomy for renal stones treatable with a single percutaneous access: a prospective randomized trial.
OBJECTIVE
To compare operative time, safety, and effectiveness of percutaneous nephrolithotomy in the supine versus prone position in a prospective randomized trial.


METHODS
From October 2005 to June 2007, 75 patients (33 men, 42 women; mean age, 39.3 yr) were prospectively enrolled and randomly divided into group A (39 patients, supine position) and group B (36 patients, prone position). Inclusion criteria were diagnosis of single or multiple renal stones (pelvic-caliceal) treatable with a single percutaneous access, stone diameter >2.5cm, body mass index (BMI) <30kg/m(2), and no contraindications to perform the operation in the prone position. Exclusion criteria were stones in more than one calyx, complete staghorn stones, and coexisting renal anomalies.


RESULTS
The two groups were comparable in age, BMI, male-to-female ratio, and stone size. No significant difference was ascertained between the two groups in terms of stone-free rate (group A, 88.7% vs. group B, 91.6%, p=0.12), mean blood loss (group A, Delta hemoglobin -2.3g/dl vs. group B, -2.2g/dl, p=0.23), and mean hospital stay (group A, 4.3 d vs. group B, 4.1 d, p=0.18). The only significant difference reported was mean operative time (group A, 43min vs. group B, 68min, p<0.001). No blood transfusions were needed and no organ injuries were reported.


CONCLUSIONS
In this carefully selected patient population with uncomplicated renal stones, the supine position was similar to the prone position for percutaneous stone removal.
De Sio
Marco
M
Clinica Urologica, Seconda Università degli Studi, Naples, Italy. marcdesio@tin.it
Autorino
Riccardo
R
Quarto
Giuseppe
G
Calabrò
Francesco
F
Damiano
Rocco
R
Giugliano
Francesco
F
Mordente
Salvatore
S
D'Armiento
Massimo
M
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D016684:Prone Position; D011446:Prospective Studies; D016683:Supine Position; D013997:Time Factors; D016896:Treatment Outcome