Study design and randomization
fracture, nerve block failure, pain, diaphragm dysfunction, fractures, nerve abnormalities, trauma
HEARING IMPAIRMENT, LUNG DISEASES, OBSTRUCTIVE SLEEP APNEA SYNDROME
Patients, ASA I or II, aged between 18 and 65 years, undergoing radius fracture surgery (open reduction and internal fixation surgery for radius fractures or internal fixation taking out operation for radius fractures) completed within 2 h between January 2020 and December 2020 were enrolled. This study was approved by the Qingdao Municipal Hospital ethics committee and registered at the China Clinical Trials Register (No. ChiCTR1900028286, principal investigator: LX Sun, date of registration: 17 December 2019). Before the experiment, we obtained the informed consent of all enrolled patients and signed the consent form.Exclusion criteria in this study were patients with lung diseases, nerve block failure, local anesthesia or neuropuncture contraindications, phrenic nerve abnormalities or diaphragm dysfunction, previous neck trauma or surgery history, rejected for participation in the study, pregnant or lactating women, obstructive sleep apnea syndrome, long-term use of pain medication, and mental, speech, or hearing impairment.All enrolled patients were divided into two groups using a random number table method (computerized program) for group I and group S. An experienced anesthesiologist who was aware of the grouping performed the nerve blocks. Neither the patients nor the follow-up investigator knew the group assignment. This double-blind, randomized and controlled single-center study was implemented in accordance with the Helsinki declaration. Allocation of the patients was according to the trial flow diagram, which is presented in Fig. 
Consolidated Standards of Reporting Trials in this study