Efficacy of TEAS on Chronic Pain and Survival in Patients Undergoing Hepatectomy

Chronic pain is defined as pain that lasts or recurs for longer than 3 months. For chronic postsurgical pain(CPSP), it mainly refers to the pain that persists past normal healing time. Pain scoring is performed at 3 months using the Numerical Rating Scale(NRS), with 11 digits ranging from 0 to 10 indicating the degree of pain, 0 indicating no pain, and 10 indicating severe pain. Subjects choose a number to indicate the degree of pain based on their personal pain experience.

Chronic pain is defined as pain that lasts or recurs for longer than 3 months. For chronic postsurgical pain(CPSP), it mainly refers to the pain that persists past normal healing time. Pain scoring is performed at 3 months using the Numerical Rating. Scale(NRS), with 11 digits ranging from 0 to 10 indicating the degree of pain, 0 indicating no pain, and 10 indicating severe pain. Subjects choose a number to indicate the degree of pain based on their personal pain experience.

Overall survival is defined as the time between the date from surgery to the date of death.

Postoperative re-examination is based on the diagnosis of enhanced CT, MRI, ultrasound or blood examination todetermine whether the patient has recurrence and metastasis. Recurrence-free time refers to the time from surgery to tumor recurrence based on the above CT, MRI, etc.

Patient self-assessment is carried out by using the World Health Organization(WHO) Disability Scale, with a minimum score of 12 points and a maximum score of 60 points. The lower the score, the higher the quality of life.

The global QoR-15 score ranges from 0 to 150 and is categorized as five quality of recovery dimensions, including physical comfort(5 items), emotional state(4 items), psychological support(2 items), physical independence(2 items), and pain(2 items). Each piece is graded using an 11-point Likert scale. The QoR is classified according to the QoR-15 score as excellent(QoR-15 > 135), good(122 ≤ QoR-15 ≤ 135), moderate(90 ≤ QoR-15 ≤ 121) and poor(QoR-15 <90).

Postoperative sleep quality is evaluated using the Athens Insomnia Scale(AIS). The AIS consists of 8 items: waking up at night, sleep induction, final awakening, total sleep duration, sleep quality, well-being, functional ability, and daytime sleepiness. The AIS score ranges from 0 to 24 points, and a total score of 6 points or higher indicates adiagnosis of insomnia.

Anxiety and depression score will be evaluated using the Hospital Anxiety and Depression Scale(HADS).The HADS consists of 14 questions, with 7 items each for the anxiety and depression subscales. The score for each item ranges from 0 to 3 points, and scores are summed to yield a separate score for anxiety(HADS-A) and depression(HADS-D).

The ID Pain scale is used as a validated assessment of neuropathic pain. ID pain questionnaire consists of six items. Pain higher scores suggest a neuropathic component to the pain.

BPI pain interference subscale is a 7-item questionnaire asking participants to describe how pain has interfered general activity, mood, walking, normal work, relations with others, sleep, and enjoyment of life. Each question is answered on a scale 0(does not interfere) to 10(completely interferes). The total range of score is 0-70. The higher the scores suggest the worse the interference.