This study was a prospective, randomized, controlled, and double-blind trial. Major assessments were made during the operation and 48 h postoperatively.

The prime outcomes were the time in minutes from leave the postoperative care unit to the first patient-controlled intravenous analgesia press.The secondary outcomes were to compare the following: (1)blood concentrations of ropivacaine was measured at 0.5 h, 1 h, 2 h, 3 h, and 24 h after paravertebral nerve block; and (2) the patient's intraoperative opioid use, phenylephrine use, fluid intake, urine output, dry mouth score, and 24 h and 48 h visual analogue scale.

Inclusion Criteria:

• (1) age 18 to 65 years,
• (2) scheduled to undergo video-assisted thoracic surgery,
• (3) American Society of Anesthesiologists risk classification I-II.

Exclusion Criteria:

• (1) patient refusal;
• (2) known hypersensitivity to the study medication (ropivacaine);
• (3) long-term use of opioids;
• (4) liver or renal insufficiency;
• (5) a history of psychiatric or neurological disease;
• (6) deafness;
• (7) regular use of acetaminophen, nonsteroidal anti-inflammatory drugs, corticosteroids, or antiemetics; and
• (8) a preoperative Pittsburgh Sleep Quality Index (PSQI) global score higher than 6.