Böhm B, Knigge M, Kraft M, Gründel K, Boenick U
Department of Surgery, Charité, Humboldt Universität, Schumanstrasse 20-21, D-10117 Berlin, Germany.
Surg Endosc. 1998 Dec;12(12):1434-8. doi: 10.1007/s004649900876.
Most trocars currently used to place a cannula through the abdominal wall have a conical or pyramidal tip. Because the risk of inadvertent injury along with removal of the cannula is probably related to (a) the force needed to traverse the abdominal wall, (b) the force needed to remove the trocar, and (c) the defect in the abdominal wall, the optimum configuration of the penetrating tip should be determined. The entry force needed to perforate the abdominal wall, the removal force necessary to remove the trocar, and the defect in the abdominal wall were measured in a porcine model under standardized conditions (general anesthesia, 12 mmHg pneumoperitoneum). Nineteen trocars (six disposable, seven reusable, six custom-made) have been tested. They were divided into six groups according to the shape of the tip (conical, pyramidal, or a combination). The entry force (F = 25.6, p < 0.0001) and the removal force (F = 5.1, p < 0.01) were related to the shape of the tip. Conical tips needed a higher force than purely pyramidal tips. The abdominal defect was also different between groups (F = 6.5, p < 0. 001). The trocar with a pyramidal shape caused a greater defect than conical tips. The defect in the abdominal wall was inversely related to the entry force (r = -0.55, p < 0.001) and to the removal force (r = -0.57, p < 0.001). There is not an optimum configuration of a simple push-through trocar with a low entry force and a high removal force. Some kind of a conical tip is recommended for insertion of trocars under direct view.
目前大多数用于经腹壁置入套管的套管针都有一个圆锥形或金字塔形的尖端。由于拔除套管针时意外损伤的风险可能与以下因素有关：（a）穿过腹壁所需的力；（b）拔除套管针所需的力；（c）腹壁的缺损，因此应确定穿刺尖端的最佳形状。在标准化条件（全身麻醉、12 mmHg气腹）下的猪模型中，测量了穿透腹壁所需的进针力、拔除套管针所需的拔针力以及腹壁的缺损情况。共测试了19根套管针（6根一次性、7根可重复使用、6根定制）。根据尖端形状将它们分为六组（圆锥形、金字塔形或两者结合）。进针力（F = 25.6，p < 0.0001）和拔针力（F = 5.1，p < 0.01）与尖端形状有关。圆锥形尖端比纯金字塔形尖端需要更大的力。各组之间腹壁缺损也不同（F = 6.5，p < 0.001）。金字塔形套管针造成的缺损比圆锥形尖端更大。腹壁缺损与进针力（r = -0.55，p < 0.001）和拔针力（r = -0.57，p < 0.001）呈负相关。不存在一种进针力低且拔针力高的简单穿刺套管针的最佳配置。建议在直视下插入套管针时使用某种圆锥形尖端。
