Evaluation of Perineural Dexmedetomidine Doses with Ropivacaine and Intravenous Dexamethasone for Analgesia in Shoulder Surgery Patients

The primary objective of this study is to evaluate the **efficacy** of different doses of perineural dexmedetomidine in prolonging the duration of the analgesic block following an interscalene plexus block. This is clinically relevant as it may enhance postoperative pain management for patients undergoing shoulder operations, potentially reducing the need for additional analgesics and improving patient outcomes.

Secondary objectives include assessing the potential side effects of higher doses of perineural dexmedetomidine, specifically **hypotension** and **bradycardia**. Additionally, the study aims to explore the potential benefits of adding dexmedetomidine, such as reduced opioid consumption, improved patient satisfaction, decreased postoperative nausea and vomiting, and enhanced sleep quality.

The clinical trial involves **patients scheduled for shoulder operations**, specifically those undergoing elective shoulder surgery. The study population includes both male and female participants, with an age range spanning from 18 to 64 years. The trial does not focus on a vulnerable population, and participants are expected to be in general good health, suitable for elective surgical procedures. The sponsor has not provided information regarding the total number of participants. Selection criteria emphasize individuals who are scheduled for shoulder surgeries, without specific lifestyle considerations such as diet or physical activity being highlighted. The trial aims to evaluate the efficacy of different doses of perineural dexmedetomidine in prolonging the analgesic block following an interscalene plexus block.

The clinical trial is designed as a **randomized**, **double-blind**, controlled study to evaluate the efficacy of different doses of perineural **dexmedetomidine** in prolonging the analgesic effect of an interscalene plexus block in patients undergoing elective shoulder surgery. The trial will involve the administration of **ropivacaine hydrochloride** as the primary anesthetic agent, with **dexmedetomidine** serving as an adjuvant, and **dexamethasone** administered intravenously. The study is categorized as a low-intervention trial, phase 3/4, and is expected to conclude by June 30, 2025, with recruitment having commenced on September 29, 2023.

Participants will be involved in the study for a maximum treatment period of one day. The trial will include several key visits: an initial screening visit to confirm eligibility based on inclusion criteria, which requires patients to be scheduled for elective shoulder surgery. Follow-up visits will be conducted to monitor the primary endpoint, which is the length of analgesia, defined as the time until the intake of additional analgesics. Secondary endpoints include the length of sensory and motor blocks, the percentage of postoperative nausea and vomiting within the first 48 hours, time to recovery after anesthesia, the percentage of side effects such as hypotension and bradycardia during anesthesia, the Numeric Rating Scale score for pain in the first 48 hours, and cumulative opioid consumption over 48 hours. The end-of-study visit will assess the overall outcomes and any adverse events experienced by the participants.

Participant involvement may be terminated early if any exclusion criteria are met post-enrollment, or if adverse events necessitate withdrawal for safety reasons. The trial will adhere to rigorous ethical standards, ensuring that all procedures are conducted in compliance with regulatory requirements and best practices in clinical research. The study aims to provide valuable insights into optimizing analgesic protocols for shoulder surgeries, potentially enhancing patient outcomes and comfort.

The clinical trial involves the administration of several treatments, including **sodium chloride**, **ropivacaine hydrochloride**, **dexmedetomidine**, and **dexamethasone**. Each treatment is administered in specific pharmaceutical forms, dosages, and routes to evaluate their efficacy in prolonging the analgesic block after an interscalene plexus block.

**Sodium chloride** is provided as "Natriumklorid B. Braun 9 mg/ml innrennslislyf, lausn," a **solution for injection/infusion**. It is administered via **perineural use**. The maximum daily and total dose is 18 mg, with a treatment period of one day. This product is manufactured by B.BRAUN MELSUNGEN AG and is not a pediatric formulation.

**Ropivacaine hydrochloride** is administered as "Ropivacaine 7.5 mg/ml solution for injection," a **solution for injection**. It is also used **perineurally**. The maximum daily and total dose is 135 mg, with a treatment period of one day. This product is manufactured by SINTETICA GMBH and is not a pediatric formulation.

**Dexmedetomidine** is provided as "Dexdor 100 micrograms/ml concentrate for solution for infusion," a **solution for infusion**. It is administered **perineurally**. The maximum daily and total dose is 0.20 mg, with a treatment period of one day. This product is manufactured by ORION CORPORATION and is not a pediatric formulation. It is used as an analgesic in the trial.

**Dexamethasone** is administered as "Dexamethason CF 20 mg/ml, injectievloeistof," a **solution for injection**. It is administered **intravenously**. The maximum daily and total dose is 10 mg, with a treatment period of one day. This product is manufactured by CENTRAFARM B.V. and is not a pediatric formulation.

All substances used in the trial are of chemical origin, and participant compliance is monitored to ensure adherence to the dosing schedules. The trial is designed to assess the efficacy of different doses of perineural dexmedetomidine in combination with ropivacaine and intravenous dexamethasone.

The efficacy of the clinical trial will be assessed by evaluating the primary and secondary endpoints. The primary endpoint is the **length of analgesia**, defined as the time until the intake of an analgesic. Secondary endpoints include the length of the sensoric block, length of the motoric block, percentage of postoperative nausea and vomiting within the first 48 hours, time to recovery after anesthesia, percentage of side effects during anesthesia such as hypotension and bradycardia, the Numeric Rating Scale score for pain during the first 48 hours, and cumulative opioid consumption over 48 hours.

These efficacy parameters will be measured and collected at specified time points throughout the trial. The trial is designed to compare different doses of perineural dexmedetomidine as an adjuvant to ropivacaine 0.67% for interscalene plexus block, in association with 10 mg intravenous dexamethasone. The trial is a single-center, double-blinded, randomized controlled trial, ensuring that the data collected is robust and reliable. The trial is expected to conclude by June 30, 2025, with recruitment having started on September 29, 2023.