2.6. Primary Outcomes
NRS, Pain, pain
In the postoperative recovery room, the time of the patient's first request for analgesics (from the time of operation termination) was recorded. After the patients retained awareness, the severity of pain was measured at intervals of 15, 30, 45, and 60 minutes according to the NRS. Pain was treated according to the following protocol: if the NRS score was less than 4, no action was taken; if it was 4 to 7, 1 mg of intravenous morphine was given every 5 minutes until achieving a score of below 4; and if the score was above 7, 2 mg of intravenous morphine was prescribed. The total amount of morphine consumed in the recovery room was recorded.After transferring the patient to the ward, an intravenous PCA pump device loaded with a 20 ml syringe containing 0.5 mg/ml morphine solution was prepared with the following settings and connected to the patient's intravenous cannula: bolus dosage = 2 ml (1 mg); lockout intervals = 7 minutes; no continuous background infusion; and maximum injection dose over 4 hours = 60 ml (30 mg). In the ward, the patient's pain was assessed via the NRS and recorded once per hour in the first 6 hours, then every 2 h for the next 6 hours, and then every 4 h for the last 12 hours. During and between each pain assessment, the protocol above was followed, with additional intravenous morphine being administrated accordingly, and the prescribed morphine was recorded separately (PCA pump morphine and additional morphine). Data collection was performed by staff unaware of each patient's study group.