We know that patients will suffer from pain to varying degrees after surgery, which is often one of the reasons why many patients are afraid of surgery. So what is the cause of postoperative pain?

        Surgical trauma is a kind of noxious stimulus, which will activate peripheral nociceptors (nociceptors are small sensory nerve endings that transmit pain signals). After the local tissue is injured, it can make the human body more responsive to stimulation (hyperalgesia), and can also cause the production and accumulation of some pain causing substances, which can make the injured tissue and its surrounding (non injured parts) produce pain feelings.

        When visceral nociceptors are activated, smooth muscle spasm, ischemia and inflammation can occur, and may also cause reference pain on the skin.

        Therefore, the pain that patients will experience after surgery can be pain at the incision (somatic pain) or visceral pain at the same time. Generally speaking, somatic pain has certain limitations, which is characterized by sharp pain, while visceral pain is not clearly located and relatively diffuse.

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