Objective: To evaluate and compare changes in pulmonary function after retroperitoneoscopic and open surgery.
Patients and methods: From June 1994 to October 1995. 11 patients (five men and six women, mean age 44.7 years, range 29-69) underwent retroperitoneoscopic procedures (Group 1) and 11 patients (eight men and three women, mean age 57.5 years, range 22-73) underwent flank-incision procedures (Group 2). The surgery comprised eight adrenalectomies and one each of nephroureterectomy, nephrectomy and pyelolithotomy in Group 1, and five adrenalectomies, four nephroureterectomies, one ureterolithotomy and one excision of a retroperitoneal tumour in Group 2. Pulmonary function tests (PFTs) were performed before and 3 days after surgery; the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), forced expiratory volume at 25% (FEV25%), FEV1/FVC, vital capacity (VC), total lung capacity (TLC), residual lung volume (RV) and functional residual capacity (FRC) were compared between the groups. The post-operative changes in the PFTs were assessed using a paired t-test and the degree of change in both groups compared using the Mann-Whitney U-test. Other factors possibly influencing PFT were analysed using multiple regression.
Results: Pulmonary function was impaired in both groups on the third day after surgery. In Group 2, the FVC, FEV1, FEV25%, VC and TLC had declined significantly (all P < 0.05) from the pre-operative value. In Group 1, only the FVC and VC decreased significantly (P < 0.05). Post-operative pulmonary complications occurred in two patients in Group 2 but in none of those in Group 1, showing that pulmonary function was generally less affected in Group 1 than in Group 2.
Conclusion: Although pulmonary function was impaired 3 days after surgery in both groups, retroperitoneoscopic surgery, by eliminating a large flank incision, caused less post-operative pulmonary dysfunction than open surgery.