Effects of surgical position on patients' arterial blood gases during percutaneous nephrolithotomy.
OBJECTIVE
To compare arterial blood gas analysis of patients who underwent percutaneous nephrolithotomy (PCNL) in flank position under ultrasonography guidance with PCNL in prone and supine positions under fluoroscopic guidance.


METHODS
In a clinical trial, a total of 90 patients with no upper urinary tract abnormalities were candidate for the PCNL. They were assigned into three groups using pseudorandomization method (30 patients in each group). Patients in group 1 underwent ultrasonography-guided PCNL in flank position. Patients in groups 2 and 3 underwent fluoroscopic-guided PCNL in prone and supine positions, respectively. Arterial blood gas was taken just before and 20 minutes after repositioning.


RESULTS
The patients' mean age was 40.8 ± 6.9, 39.4 ± 10.6, and 37.2 ± 11.1 years in flank, prone, and supine positions, respectively (P = .69). The mean body mass index was 27.8 ± 3.4, 26.7 ± 4.7, and 28.1 ± 5.1 kg/m² in flank, prone, and supine positions, respectively (P = .21). Arterial oxygen pressure (PaO₂) increased significantly in flank (111.7 ± 43.8 to 132.8 ± 58.1 mmHg; P = .01) and prone (118.6 ± 50.2 to 134.6 ± 58.5 mmHg; P < .001) positions and decreased nonsignificantly in supine group (121.7 ± 64.5 to 119.7 ± 60.9 mmHg; P = .23). With surgical positioning, there were no significant changes demonstrated in PaCO₂ and serum concentration of HCO₃ in the flank, prone, and supine groups.


CONCLUSIONS
We could suggest that flank and prone positions could improve patients' oxygenation during PCNL procedure.
Shohada-e-Tajrish Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Hossein
H
Karami
Ali Reza
AR
Rezaei
Mohammad Mohsen
MM
Mazloomfard
Babak
B
Javanmard
Behzad
B
Lotfi
Amir
A
Haji-Mohammadmehdi-Arbab
D000328:Adult; D001639:Bicarbonates / Q000097:blood; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery*; D008297:Male; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D010100:Oxygen / Q000097:blood*; D056888:Patient Positioning / Q000379:methods*; D016684:Prone Position; D016683:Supine Position; D014463:Ultrasonography
D001639:Bicarbonates; D002245:Carbon Dioxide; D010100:Oxygen