To compare the effects of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) on pulmonary function and blood lipid levels in patients with severe obesity.

90 patients with severe obesity (BMI ≥ 35kg/m²) admitted to two hospitals from November 2014 to November 2017 were analyzed retrospectively, and the patients were treated with LSG (n=48) or LRYGB (n=42). The SPSS 19.0 was used for statistical analysis, and the general data, lung function indexes, physiological indexes and blood lipid levels were compared by (±s). The independent t test or one-way ANOVA was used for comparison between groups. The enumeration data was tested by χ². P<0.05 indicated that the statistical difference was significant.

The surgical and anesthesia durations in LSG group were lower than those in LRYGB group, and the differences were statistically significant (P<0.05). And the amount of blood loss during surgery between the two groups showed no statistically significant difference (P>0.05). There was no significant difference in lung function between the groups before surgery. The levels of PaO₂, FVC, FEV1 and MMF in both groups were all significantly decreased after surgery (P<0.05). The levels of PaO₂, FVC, FEV1 and MMF in both groups at 48 h after surgery were all significantly improved than those at 24 h after surgery (P<0.05), but were still significantly lower than those before surgery (P<0.05). The levels of PaO₂, FVC, FEV1 and MMF in LSG group were all higher than those in LRYGB group at 24 h and 48 h after surgery, and the differences were statistically significant (P<0.05). The levels of weight, BMI, waist circumference, hip circumference, fasting blood glucose and 2-hour postprandial blood glucose in both groups at 6 months after surgery were all decreased than those before surgery, and the differences were statistically significant (P<0.05); however, there was no statistically significant difference between the two groups (P>0.05). The levels of TG, CH and LDL in both groups at 6 months after surgery were significantly decreased than those before surgery, while the HDL level was significantly increased (P < 0.05); however, there was no statistically significant difference between the two groups (P>0.05).

LRYGB and LSG have the similar result in weight loss and have no significant difference in improving blood lipids, but LSG has less effects on short-term lung function and oxygenation compared with LRYGB.