Intraoperative S-ketamine to Prevent Postoperative Hyperalgesia in Patients Undergoing Video-assisted Thoracic Surgery

Second Affiliated Hospital Zhejiang University School of Medicine

Postoperative hyperalgesia (POH) is a paradoxical clinical state of increased sensation of pain or increased sensitivity to non-painful stimuli at the site of surgery or at a surrounding area that was not directly injured. Opioid-induced hyperalgesia (OIH) and nociceptive-induced hyperalgesia (NIH) are the two main causes of POH.N-methyl-D-aspartate receptor (NMDAR) activation plays a central role in the development of POH.S-ketamine，which is a NMDA-receptor antagonist,has been on the market in china since 2019.The aim of this study is to evaluate the effects of S-ketamine on POH and chronic postoperative pain after video-assisted thoracic surgery.

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) physical status class I-III.
• elective single-port video-assisted thoracic surgery under general

Exclusion Criteria:

• a history of thoracic surgery
• a history of chronic pain
• ongoing pain treatment
• opioid drug or alcohol abuse
• a history of allergy to anesthetics
• obesity (body mass index [BMI] >30 kg/m2 )
• pregnancy
• psychiatric disorders
• neurological disease
• severe diabetes
• renal or hepatic insufficiency
• uncontrolled hypertension, or arrhythmia