Immunologic changes during minimally invasive surgery.

Although recent experimental and clinical trials have documented that postoperative inflammation and changes in different immunologic parameters are less pronounced after laparoscopic approaches in comparison to open surgery, it still remains unclear what influence the pneumoperitoneum itself has on immunologic defense and function. This is mainly due to the endpoints of the different studies which investigate changes in the so-called immunologic parameters (cell subunits, C-reactive protein, cytokines, catecholamines or other stress hormones in plasma samples) rather than analyzing immunologic functions, such as cell activation, production of proteins, cell proliferation or in vivo immune defenses. So far, especially in clinical trials, no correlation has been demonstrated between the changes in immunologic parameters and relevant postoperative clinical endpoints, such as postoperative complications. Thus further clinical prospective randomized studies with relevant clinical endpoints and additional investigations of immunologic parameters are needed to prove the consequences of either minimally invasive surgery or open procedures on postoperative immune functions.