Sleep is a naturally occurring state of decreased arousal that is crucial for normal immune and cognitive function. Although surgery and anesthesia techniques have improved in recent years, sleep function and sleep cycles may still be altered perioperatively by surgery and other interventions under general anesthesia.Postoperative sleep fragmentation and poor sleep quality not only lead to hyperalgesia and delayed postoperative recovery, but can increase the risk of potential adverse effects, such as cognitive impairment, chronic pain and emotional disturbances, metabolic disorders, and pro-inflammatory changes. General anesthesia is a medically induced state of hyporesponsiveness that resembles natural sleep. Studies have shown that general anesthesia can lead to circadian rhythm time structure dyssynchrony, resulting in postoperative sleep disturbance, characterized by decreases in rapid eye movement (REM) and slow wave sleep (SWS). Previous studies have also reported that age, preoperative comorbidities, and severity of surgical trauma are independent factors associated with postoperative sleep disturbance. In addition, anxiety is an unpleasant sensation that compromises patients' comfort and well-being. A study by Ruis et al. estimated that 25-80% of patients admitted for surgery experienced preoperative anxiety, including fear of surgery and anesthesia-related fears. Furthermore, preoperative anxiety was recognized as a potential and preventable risk factor for severe postoperative pain and postoperative complications such as increased postoperative morbidity and mortality. Given that several prior studies have reported that preoperative anxiety has an effect on postoperative sleep quality in patients undergoing gynecological surgery, this study aimed to investigate the effect of preoperative anxiety on postoperative outcomes and sleep quality in patients undergoing gynecological surgery. Studying these results could enable us to better manage patients during the perioperative period to promote their postoperative recovery.

The inclusion criteria were:

1. age between 18 and 75 years,
2. American Society of Anesthesiologists (ASA) medical status I or II,
3. laparoscopic hysterectomy, elective operation and surgery lasting 1-3 h.

The exclusion criteria included

1. cardiovascular disease,
2. chronic use of analgesics,
3. chronic use of antidepressants,
4. use of sleep-promoting drugs,
5. sleep disorders,
6. sleep apnea syndrome,
7. history of abnormal surgery or recovery from anesthesia,
8. psychosis,
9. patients with impaired verbal communication,
10. unwillingness to provide informed consent.

This study enrolled patients undergoing gynecological surgery under general anesthesia at Shengjing Hospital of China Medical University.