A single centre parallel-group randomized control trial of Magnetic Resonance Assessment of Variations in Effects of anaesthesia on renaL perfusion in children

The primary objective is to evaluate the effects of propofol and sevoflurane on renal blood flow in paediatric patients. This assessment is clinically relevant for understanding how these commonly used anaesthetic agents influence renal perfusion, which may have implications for the prevention of post-operative acute kidney injury in children undergoing general anaesthesia.

The secondary objectives include:

• To explore the effect of sevoflurane and propofol on serum renin concentration as a surrogate marker for renal sympathetic nerve activation.

• To investigate how renal blood flow varies in relation to systemic blood pressure in paediatric patients in general anaesthesia with propofol or sevoflurane.

• To explore potential differences related to sevoflurane or propofol on regional and global renal oxygenation.

• To investigate the effect of propofol and sevoflurane on regional tissue perfusion in the renal cortex and medulla.

The sponsor did not provide information regarding the total number of participants for this clinical trial. The study population consisted of **pediatric patients** ranging from **1 month to 14 years of age**, including both **male** and **female** subjects. Participants were selected based on the requirement for **MRI** with **anesthesia** and an **ASA physical status** classification of **I-III**, indicating patients with no systemic disease to severe systemic disease. The trial focused on evaluating the effects of **Propofol** and **Sevoflurane** on **renal blood flow** in the context of **post-operative acute kidney injury**. No information was provided regarding lifestyle considerations such as diet, physical activity, or habits of the participants.

This study is designed as a **single-centre**, **parallel-group**, **randomized controlled trial** to evaluate the effects of **propofol** and **sevoflurane** on **renal blood flow** in **paediatric patients**. The trial is classified as a **low-intervention Phase IV clinical trial**, as both anaesthetic agents are authorized and frequently used in daily clinical practice. The primary objective is to assess differences in renal blood flow between the two anaesthesia regimens, measured by **phase contrast imaging** with **multiparametric magnetic resonance imaging**. Secondary endpoints include the difference in **plasma renin concentration**, the relationship of renal blood flow to systemic **non-invasive blood pressure**, differences in regional and global **renal oxygenation** as measured by **Blood Oxygen Level Dependent signal**, and differences in regional renal tissue perfusion measured by **arterial spin labelling**.

Eligible participants include pediatric patients aged 1 month to 14 years who are indicated for **magnetic resonance imaging** with anaesthesia and have an **American Society of Anesthesiologists physical status** of I to III. Participants will be randomized to receive either propofol or sevoflurane as the anaesthetic agent. Propofol will be administered via **intravenous bolus injection** or **intravenous infusion** at a maximum dose of 14 mg/kg/h, while sevoflurane will be administered via **inhalation** at a maximum concentration of 5 percent. The maximum treatment period for both agents is 1 day.

The estimated recruitment start date is October 2025, with an anticipated trial completion date of December 2026. Participant involvement is expected to be limited to the duration of the anaesthesia and imaging procedure, along with any necessary follow-up assessments. The trial protocol may allow for early termination of individual participants under specific conditions, such as adverse events, protocol deviations, or withdrawal of consent, although such conditions are not explicitly detailed in the available information. The study aims to provide insights into the renal effects of commonly used anaesthetic agents in the paediatric population, with a focus on **post-operative acute kidney injury**.

The clinical trial investigates two experimental medications administered to paediatric patients. **Propofol** serves as one of the test medicinal products in this study. This agent is administered via **intravenous bolus injection** or **intravenous infusion**. The maximum dosage is 14 milligrams per kilogram per hour, with a maximum treatment period of one day. Propofol, also known by its chemical designation 2,6-Bis(propan-2-yl)phenol or by the synonyms ICI-35868 and disoprofol, is classified under **ATC code** N01AX10. The active substance is of chemical origin.

**Sevoflurane** constitutes the second experimental medication evaluated in this trial. This medicinal product is administered via **inhalation**. The maximum concentration is 5 percent, with a maximum treatment period of one day. Sevoflurane is classified under ATC code N01AB08. The active substance is of chemical origin. Both medicinal products function as test agents in this parallel-group randomized controlled trial designed to assess variations in effects of anaesthesia on renal perfusion in children, specifically evaluating impacts on **renal blood flow**.

The primary efficacy endpoint is the difference in renal blood flow between propofol and sevoflurane anesthesia, as measured by phase contrast imaging with multiparametric magnetic resonance imaging. Secondary efficacy endpoints include the difference in plasma renin concentration between propofol and sevoflurane anesthesia, measured by blood sample analysis. Additionally, the difference in the relation of renal blood flow to systemic non-invasive blood pressure between the two anesthetic agents will be assessed. Further secondary endpoints comprise differences in regional and global renal oxygenation, as measured by Blood Oxygen Level Dependent signal via multiparametric magnetic resonance imaging, and differences in regional renal tissue perfusion, as measured by arterial spin labelling with multiparametric magnetic resonance imaging, between propofol and sevoflurane anesthesia.