Impact of low-dose intrathecal morphine on orthopedic surgery: a protocol of a systematic review and meta-analysis of randomized controlled trials

Review question / Objective: Patients undergoing orthopedic surgery usually suffer considerably from peri-operative pain and intrathecal morphine (ITM) has recent been used as an effective analgesia method. The intrathecal morphine dose achieving optimal analgesia for orthopedic surgery while minimizing side effects has not yet been determined. There is currently a lack of literature synthesis in the safety and effects of low-dose ITM on orthopedic surgery. Condition being studied: Low-dose intrathecal morphine on orthopedic surgery. Information sources: We will search the following electronic databases, registries and websites on January 11th 2022, unrestricted by date. Grey literature and non-English studies will not be excluded. English Databases: PubMed, Cochrane library and Web of science. Chinese database: Cnki.net Trial registries: ClinicalTrials.gov.