Dexmedetomidine versus Propofol: Is One Better Than the Other for MRI Sedation in Children?

Intranasal Dexmedetomidine With Intravenous Midazolam: A Safe and Effective Alternative in the Paediatric MRI Sedation

Background and aims MRI sedation in paediatrics includes challenges like respiratory depression, maintaining haemodynamic stability and use of neuroprotective drugs, since MRI is performed in remote places outside the operating room with a lack of support staff and nonavailability of choice of medications and equipments. The primary aim was to use a combination of the drugs to encounter the above challenges and look for its efficacy. The secondary aim of the study was to determine the rate of successful completion of MRI in children using a combination of intranasal dexmedetomidine and intravenous midazolam - without the need for rescue sedatives. Methods This is an observational study involving 60 children in the age group between two months and six years undergoing an MRI. Children belonging to the American Society of Anesthesiology (ASA) 1 and 2 were given intranasal dexmedetomidine 3µg/kg, time to onset of sedation was noted and injection of midazolam 0.1 mg/kg was given intravenously. MRI was started once the child was asleep. Children who woke up during the MRI were supplemented with inj. propofol 0.5-1mg/kg and were documented. Results The median time duration for MRI was 38.7 min and the onset of sedation after intranasal dexmedetomidine was 18.7 min. The scan was successfully completed with a combination of intranasal dexmedetomidine and intravenous midazolam in 86.7% and only 13.3% of the children woke up either at the start or in between the scan and required the addition of propofol. Conclusion Drugs used for sedation during MRI should not cause respiratory depression and be safe for the developing brain. The above study has shown that a combination of intranasal dexmedetomidine and intravenous midazolam is effective and safe in performing MRIs in paediatrics.

Drug selection for sedation and general anesthesia in children undergoing ambulatory magnetic resonance imaging

The demand for drug-induced sedation for magnetic resonance imaging (MRI) scans have substantially increased in response to increases in MRI utilization and growing interest in anxiety in children. Understanding the pharmacologic options for deep sedation and general anesthesia in an MRI environment is essential to achieve immobility for the successful completion of the procedure and ensure rapid and safe discharge of children undergoing ambulatory MRI. For painless diagnostic MRI, a single sedative/anesthetic agent without analgesia is safer than a combination of multiple sedatives. The traditional drugs, such as chloral hydrate, pentobarbital, midazolam, and ketamine, are still used due to the ease of administration despite low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, and propofol, with high effectiveness and rapid recovery, are preferred for children undergoing ambulatory MRI. General anesthesia using propofol or sevoflurane can also provide predictable rapid time to readiness and scan times in infants or children with comorbidities. The selection of appropriate drugs as well as sufficient monitoring equipment are vital for effective and safe sedation and anesthesia for ambulatory pediatric MRI.

Effect of xenon and dexmedetomidine as adjuncts for general anesthesia on postoperative emergence delirium after elective cardiac catheterization in children: study protocol for a randomized, controlled, pilot trial

Background

Emergence delirium, a manifestation of acute postoperative brain dysfunction, is frequently observed after pediatric anesthesia and has been associated with the use of sevoflurane. Both xenon and dexmedetomidine possess numerous desirable properties for the anesthesia of children with congenital heart disease, including hemodynamic stability, lack of neurotoxicity, and a reduced incidence of emergence delirium. Combining both drugs has never been studied as a balanced-anesthesia technique. This combination allows the provision of anesthesia without administering anesthetic drugs against which the Food and Drug Administration (FDA) issued a warning for the use in young children.

Methods/Design

In this phase-II, mono-center, prospective, single-blinded, randomized, controlled pilot trial, we will include a total of 80 children aged 0–3 years suffering from congenital heart disease and undergoing general anesthesia for elective diagnostic and/or interventional cardiac catheterization. Patients are randomized into two study groups, receiving either a combination of xenon and dexmedetomidine or mono-anesthesia with sevoflurane for the maintenance of anesthesia.

The purpose of this study is to estimate the effect size for xenon-dexmedetomidine versus sevoflurane anesthesia with respect to the incidence of emergence delirium in children. We will also describe group differences for a variety of secondary outcome parameters including peri-interventional hemodynamics, emergence characteristics, incidence of postoperative vomiting, and the feasibility of a combined xenon-dexmedetomidine anesthesia in children.

Discussion

Sevoflurane is the most frequently used anesthetic in young children, but has been indicated as an independent risk factor in the development of emergence delirium. Xenon and dexmedetomidine have both been associated with a reduction in the incidence of emergence delirium. Combining xenon and dexmedetomidine has never been described as a balanced-anesthesia technique in children. Our pilot study will therefore deliver important data required for future prospective clinical trials.

Trial registration

EudraCT, 2018–002258-56. Registered on 20 August 2018. https://www.clinicaltrialsregister.eu.