Pulmonary Atelectasis Following Upper Urinary Tract Surgery on Patients in the 2° and 45° ‘Jack-Knife’ Position

The development of pulmonary atelectasis following upper urinary tract surgery in patients positioned either in the 25° or the 45° ‘jack-knife’ position was evaluated in a randomized clinical trial with sequential analysis. Atelectasis was diagnosed from chest radiographs and/or from a decrease in arterial oxygen tension during the first three postoperative days. 32.1% of 78 patients developed atelectasis, but no statistically significant differences was found between the two positions.