Immunologic postoperative competence after laparoscopy versus laparotomy

Sepsis is a major complication associated with increased morbidity and mortality in patients treated surgically for hepatobiliary and colorectal diseases. Impairment of immune function after surgery may be one of the mechanisms causing increased susceptibility to infection. From November 1999 to October 2001, the perioperative and postoperative immune responses of 20 patients who underwent laparoscopy were compared with those of 20 patients who underwent laparotomy. All the patients were affected by benign pathologies. The current study aimed to elucidate the differences between the immune responses induced by the two different surgical approaches.

Immunologic function was assessed by a count of lymphocyte subsets (CD3, CD4, CD8, CD3-HLA-DR, CD19, CD16, CD57) and monocytes expressing human leukocyte antigen DR (HLA-DR). Blood samples were obtained 1 day before the surgical therapy, then 2 and 8 days after therapy. For statistical analysis, the continuous variables were compared using Student's t-test. Probability values less than 0.05 were considered significant.

With regard to T-lymphocyte function, a fall 2 days after surgery was assessed for both laparoscopy (p < 0.0005) and laparotomy (p < 0.00003) groups. At 8 days after surgery, these values had returned to the preoperative level on both groups. The activity of B-cells and natural killer cells was not significantly affected, whereas the number of monocytes expressing HLA-DR showed a long-lasting decrease after laparotomy (p < 0.011 2 days after surgery and p < 0.02 8 days after surgery), but not after laparoscopy.

Impairment of cell-mediated immune function after surgery was demonstrated especially in patients treated by laparotomy, as compared with those treated by laparoscopy.