Does CO2 pneumoperitoneum in laparoscopy interfere with collagen deposition in abdominal surgical wounds?

Abstract Purpose To determine by histomorphometric analysis whether CO2 pneumoperitoneum interferes with collagen deposition in surgical wounds in the aponeurosis of rats. Methods This experiment involved 80 male Wistar rats, randomly allocated into four groups according to pneumoperitoneum period (PRE: 30 min preoperatively; POST: 30 min postoperatively; PP: 30 min pre- and postoperatively; C: control group). CO2 pneumoperitoneum was insufflated to 5 mmHg of pressure. A laparotomy was performed; 1 cm of the left colon was then resected, and an end-to-end anastomosis was performed to simulate surgical trauma, after which the abdominal wall was closed. On postoperative days 7 or 14, a sample of the abdominal wall was collected, stained with picrosirius red and observed under polarized light in an optical microscope. The amount of collagen was estimated by computerized histomorphometric analysis. Results There were no significant differences in collagen deposition between the control and experimental groups on postoperative days 7 (p=0.720) or 14 (p=0.933). The amount of collagen increased as expected in all groups between postoperative days 7 and 14 (p=0.0003). Conclusion At 5 mmHg, CO2 pneumoperitoneum does not interfere with collagen deposition in abdominal wall surgical wounds in rats.摘要 ## 研究目的 通过组织形态计量分析（histomorphometric analysis），探究二氧化碳气腹（CO₂ pneumoperitoneum）是否会干扰大鼠腱膜手术切口的胶原沉积。 ## 实验方法 本实验共纳入80只雄性Wistar大鼠，按气腹干预时长随机分为四组：PRE组（术前30分钟）、POST组（术后30分钟）、PP组（术前及术后各30分钟）、C组（对照组）。以5mmHg压力实施二氧化碳气腹充气，随后进行剖腹手术，切除1cm左侧结肠并行端端吻合（end-to-end anastomosis）以模拟手术创伤，最后缝合腹壁。分别于术后第7天或第14天采集腹壁样本，采用天狼星红（picrosirius red）染色后置于偏光光学显微镜下观察，通过计算机辅助组织形态计量分析估算胶原沉积量。 ## 实验结果 术后第7天（p=0.720）及第14天（p=0.933），对照组与各实验组的胶原沉积量均无显著差异；所有组别在术后7天至14天期间的胶原含量均如预期升高（p=0.0003）。 ## 研究结论 当气腹压力为5mmHg时，二氧化碳气腹不会对大鼠腹壁手术切口的胶原沉积产生干扰。