The Study on the Effect of Acetaminophen on Postoperative Delirium in Orthopedic Surgery by its Analgesic Action

JRCT ID: jRCTs041220161

Registered date:01/04/2023

Basic Information

• Recruitment status: Recruiting
• Health condition(s) or Problem(s) studied: orthopedic disease
• Date of first enrollment: 01/04/2023
• Target sample size: 300
• Study type: Interventional

Intervention(s)

For the acetaminophen treated group, acetaminophen is administered as a postoperative analgesic at a dose of 1000 mg intravenously over 15 minutes at the time of wound closure for patients weighing 50 kg or more. Thereafter, it is administered every 6 hours starting 6 hours after the end of surgery. A total of 9 doses are administered (at the time of wound closure and 6, 12, 18, 24, 30, 36, 42, and 48 hours after the end of surgery).
For patients weighing less than 50 kg, 15 mg per kg of body weight is administered intravenously over 15 minutes at the time of wound closure. Thereafter, the dose is administered every 6 hours starting 6 hours after the end of surgery. A total of 9 doses (at wound closure and 6, 12, 18, 24, 30, 36, 42, and 48 hours after the end of surgery).
Acetaminophen is not routinely administered to the acetaminophen non-treated patients.

Outcome(s)

• Primary Outcome: Incidence of delirium according to CAM Japanese version

Secondary Outcome

Postoperative pain VAS (6, 24, 48 hours, 3, 7 days postoperatively)
Therapeutic acetaminophen administration up to 48 hours postoperatively for acetaminophen non-treatment group
Total opioid dose during hospitalization
Time from postoperative to discharge
Presence of psychiatric intervention at the time of delirium

Key inclusion & exclusion criteria

• Age minimum: >= 18age old
• Age maximum: Not applicable
• Gender: Both

Include criteria

Over 18 years old
Patients undergoing orthopedic surgery under general anesthesia
The patient must understand the study and give written consent.
Patients must be able to maintain major organ function and meet all of the following criteria
(1) AST Less than 5 times the upper limit of the institutional reference value
(2) ALT Less than 5 times the upper limit of the institutional reference value
(3) Total bilirubin Less than 3 times the upper limit of the institutional reference value
(4) Creatinine Less than 3 times the upper limit of the institutional reference value
(5) No occurrence of events that, in the judgment of the investigator, would make it difficult to administer the study drug.

Exclude criteria

Symptoms of Grade 3 or higher (CTCAE v5.0) or abnormal laboratory values
Patients with a history of hypersensitivity or intolerance to acetaminophen or NSAIDs
Patients with a history of hypersensitivity or intolerance to acetaminophen or NSAIDs.
Patients with peptic ulcer.
Patients with serious blood disorders.
Patients with serious hepatic disorder.
Patients with serious renal failure.
Patients with serious cardiac dysfunction.
Patients with aspirin asthma (non-steroidal anti-inflammatory analgesics induced asthma attack) or a history of aspirin asthma.
Patients who are judged by the principal investigator to be unsuitable to participate in this study.

Related Information

• Primary Sponsor: Nakashima Hiroaki