Respiratory function after aortic aneurysm repair: a comparison between retroperitoneal and transperitoneal approaches

Objective: Elective abdominal aneurysm repair can be performed by using the transperitoneal or the retroperitoneal approach. The latter has been described as having a better outcome, reducing the impairment of respiratory function or the incidence of lung complications. Hence the retroperitoneal approach has been proposed for treatment of medically high-risk patients. However, the superiority of one technique or the other in preserving pulmonary function has not been conclusively demonstrated. The aim of this study was to ascertain whether the retroperitoneal and the transperitoneal approaches differently affect respiratory function. Design: A prospective randomised study Setting: Two four-bed surgical-medical ICUs of a University hospital Patients: Twenty-three consecutive patients undergoing abdominal aortic aneurysm repair were randomised to the retroperitoneal (12 patients) and transperitoneal approach. they were studied a) within 30 min and b) 8 hours after the end of surgery c) during a T-piece tube weaning trial. Measurements: The comparison between the two groups was based on respiratory mechanics, partitioned between lung and chest wall components, basic spirometry, tension-time index of the inspiratory muscle, weaning indexes and length of stay both in ICU and hospital. Results: The two surgical techniques have no different impact on either respiratory mechanics or inspiratory muscle function or weaning indexes. However, there was a tendency for retroperitoneal patients to stay less both in ICU and in the hospital. Conclusions: During the first 24 hours after surgery, the postoperative impairment of respiratory function is independent on the surgical approach.