Comparative assessment of TNF-α and C-reactive protein in patients subjected to open instead of laparoscopic cholecystectomy

Background : C-reactive protein (CRP) and tumor necrosis factor-α (TNF- α) are specific proteins modulated by the acute stress of surgery. Various retrospective and prospective studies have demonstrated subdued stress responses in laparoscopically operated patients vis-à-vis the conventional (open) method.
Aim : To assess the roles of TNF- α and C-reactive protein levels as tentative stress markers in correlating the extent of perioperative immune modulation during open and laparoscopic cholecystectomy in a subset of an Indian population.
Setting and Design : This study is a prospective study.
Materials and Methods : Forty patients admitted and operated over a period of two years, were assigned to two groups: laparascopic cholecystectomy (LC) (Group-I) or open cholecystectomy (OC) (Group-II). Selection was based on: patients′ preference, patients′ insistence, patients′ inability to afford the laparoscopic procedure, lack of expertise or lack of facility in the hospital for the laparoscopic procedure. The baseline characteristics in terms of anesthetic protocol, fluid management, postoperative orders and perioperative care were kept similar for both groups.
Statistical Analysis : SPSS v.11 was used for statistical computations.
Results : Baseline values of CRP in the OC and LC Groups were 7.9959 ± 5.57837 µg/ml and 11.3948 ± 11.61055 µg/ml respectively. CRP values rose markedly during the intra- as well as the postoperative periods till day 4 ( P < 0.001) in both the groups. Intragroup variations were not significantly different from each other ( P > 0.05). No such trend was noticed for TNF-α levels under identical conditions. Indeed, the TNF-α levels were 2.0304 ± 5.67384 pg/ml and 11.3408 ± 25.09385 pg/ml in the OC and LC groups respectively. Intragroup changes were not significantly different from each other ( P > 0.05). Percentage changes in CRP and TNF-α were higher after OC in comparison to LC.
Conclusions : The present study did not record statistical differences in the levels of the two markers (CRP, TNF-α) between the two groups. This reflects the limited tissue trauma due to easy and simple visceral tissue dissection in the two types of nondifficult surgery intraoperatively. However, greater change ( P = 0.09) of TNF levels (30% vs. 1.9%) in the OC group on the 4^th postoperative day represents the possibility of greater immune modulation in the OC group postoperatively.

Keywords
C-reactive protein, laparoscopic cholecystectomy, open cholecystectomy, stress response, TNF-α