Effect Of Various Laparoscopy On Systematic Immune Function And PH Value Of The Abdominal Cavity And Arterial Blood In A Rat Model

OBJECTIVE: To observe the effect of laparotomy and various laparoscopic surgery on systematic immune functionand pH values of abdominal cavity and arterial blood in a rat model. And to further evaluate the effect of laparoscopy on the growth and metastasis of malignant tumor.STUDY DESIGN: seventy-five female S-D rats, about 250g of each, were divided randomly into five groups: (1)laparotomy, (2)carbon dioxide pneumoperitoneum laparoscopy, (3)gasless laparoscopy, (4)nitrogen gas pneumoperitoneum laparoscopy and (5) control group(no surgical intervention,just as the preoperative blood pH value and CD T cell counts control), fifteen rats of each group, and simulated the laparotomy and various laparoscopy procedures for 1h every sample. Preoperative and postoperative carotid artery blood gas analyses and local pH of abdominal cavity were tested to evaluate the changes of the systematic and local acid-base balance. The pre and postoperative blood CD3, CD4 and CD8 T cells counts were measured on day 0, 1, 3 and 7 respectively to discover the postoperative changes of systematic immune function. RESULTS: 1.Results of preoperative and postoperative pH values detected by blood gas analyses: laparotomy (preoperation7.3889±0.0177,postoperation7.3852±0.0117,P＞0.05), carbon dioxide pneumoperitoneum laparoscopy (7.3877±0.0264,7.0918±0.0705,P＜0.001＝, gasless laparoscopy (7.3889±0.0200,7.3891±0.0132,P＞0.05), nitrogen gas pneumoperitoneum laparoscopy (7.3869±0.0200,7.3786±0.0073,P＞0.05) and control group (7.3880±0.0074). There were no differences of pH values between among every groups before experiment (P＞0.05). However there was a significant decrease of pH values in CO2 group after surgery (P＜0.001＝ and a slight decrease in group 4 but there was no differences (P＞0.05) when compared with the preoperative pH values of each group. There were no significant decrease of pH in group 1 and 3 (P＞0.05). The postoperative pH values were significantly lower in group 2 than those in the other four groups. There were no differences between group 1 and 3 compared with control group (P＞0.05). Although the values of group 4 is lower than those of group 1, 3 and 5, there were no any statistic differences when compared with the three groups (P＞0.05). The results of the preoperative and postoperative pH values changes of abdominal cavity were: laparotomy (7.3849±0.0207,7.3831±0.0253,P＞0.05),carbon dioxide pneumoperitoneum laparoscoppy (7.3867±0.0226,6.3740±0.1841,P＜0.001), gasless laparoscopy (7.3840±0.0236,7.3820±0.0242,P＞0.05), nitrogen gas pneumoperitoneum laparoscopy (7.3840±0.0210,7.3860±0.0168,P＞0.05). There were no any statistic decrease in the groups except in group 2(P＜0.001). 2. Changes of systematic immune function in every group: (1)There were no significant differences in CD3, CD4 and CD8 T cells counting, i.e. there were no differences of systematic immune function among the five groups before examination (P＞0.05). (2)The postoperative CD3, CD4 and CD8 counting results of the four processed groups (group 1 to 4) decreased obviously in comparison with the preoperative counts and control counts on day 1 (P＜0.001), especially lower in group 1(P＜0.001). In three laparoscopic surgery groups, the counting results in group 2 decreased much more than those in group 3 and 4(P＜0.001), but there were no statistic differences between the latter two groups (P＞0.05). (3)All the counting values of the four groups rised on day 3. The values had nearly the same fastest rise in group 3 and 4 (P＜0.01) and the slowest rise in group 1(P＜0.01) with a middle rise of group 2 in between (P＜0.01compared with group 1; P＜0.01compared with group 3, 4). (4)The CD counting values recovered to normal on day 7 in the four groups compared with control group(P＞0.05) and the preoperative counts of each group respectively. CONCLUSION: 1.There were no significant effect of laparotomy, gasless or N2 pneumoperitoneumon laparoscopy on the pH values of arterial blood and abdominal cavity...