Your body is really good.

Zheng Ren could not be bothered to watch such a difficult surgery.

He sat on a small stool and could tell which stage the surgery was at just by looking at Su Yun's hand movements from afar.

He opened up his chest, looked for, dissociated, and cut off the extraordinary veins, and exposed the rupture point on the right back of the trachea.

To be honest, Zheng Ren did not know why the rupture point was on the right rear. If one were to use logic to explain it, it might be that the windpipe ruptured due to local pressure being too high.

External injuries came in all sorts of ways, and a slight difference in an angle could lead to different results. Zheng Ren did not have any ideas or concepts about physics, and he did not want to specialize in it.