Systemic stress response after laparoscopic and open gastric bypass

BACKGROUND: The magnitude of the systemic stress response is proportional to the degree of operative trauma. We hypothesized that laparoscopic gastric bypass (GBP) is associated with reduced operative trauma compared with open GBP, resulting in a lower systemic stress response. STUDY DESIGN: Forty-eight patients with a body mass index of 40 to 60 were randomly assigned to laparoscopic (n = 26) or open (n = 22) GBP. Blood samples were measured at baseline and at 1, 24, 48, and 72 hours postoperatively. Metabolic (insulin, glucose, epinephrine, norepinephrine, dopamine, ACTH, cortisol), acute phase (C-reactive protein), and cytokine (interleukin [IL]-6, IL-8, tumor necrosis factor [TNF]-α) responses were measured. Catabolic response was also measured by calculating the nitrogen balance at 24 and 48 hours postoperatively. RESULTS: The two groups of patients were similar in terms of age, gender, and preoperative body mass index. The mean operative time was longer for laparoscopic GBP than for open GBP (229 ± 50 versus 207 ± 43 minutes). After laparoscopic and open GBP, plasma concentrations of insulin, glucose, epinephrine, dopamine, and cortisol increased; IL-8 and TNF-α remained unchanged; and negative nitrogen balances occurred at 24 and 48 hours. There was no significant difference in these parameters between groups. Concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 levels also increased, but these levels were significantly lower after laparoscopic GBP than after open GBP (p < 0.05). CONCLUSIONS: Systemic stress response after laparoscopic GBP is similar to that after open GBP, except that concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 are lower after laparoscopic than after open GBP. These findings may suggest a lower degree of operative injury after laparoscopic GBP.