Guidelines for the safe provision of anaesthesia in magnetic resonance units 2019

The European MR safety landscape

OBJECTIVES

Despite the absence of ionizing radiation, magnetic resonance (MR) has inherent risks in clinical practice that can have serious health consequences if overlooked. At an international level, there are MR safety guidelines that help define the organization of a radiology department to minimize the risks for patients and personnel. However, competing guidelines exist and not every country and institution adheres to the same standards. In this work, we aim to understand the current situation regarding MR safety practices across Europe, and to identify the points where harmonization, coordination, or further education is needed.

METHODS

An anonymous survey questionnaire was distributed between April and June 2023 through ESR member societies to healthcare professionals, aimed to assess personnel training, local policies, scanning practices, and accidents.

RESULTS

Seven hundred and ninety-three responses were obtained from 44 different countries. The majority of respondents from five countries reported that MR safety is mandated by law, but we could only confirm two (Italy and Austria). While 77% of the responses said that their institution had a clear MR safety guideline, 52% said that nobody in their institution had received specific MR safety training. MR-conditional cardiac devices are mostly scanned in university hospitals (reported by 75% of respondents from this type of institution) but in only 42% of outpatient facilities. MR-unsafe cardiac devices are only scanned off-label in 27% of university hospitals, and in an even smaller share of other institutions. Approximately 12% of the respondents reported MR-related accidents resulting in patient or personnel injury. Overall, there is the sentiment that MR safety education and regulation are needed.

CONCLUSIONS

The European landscape in terms of MR safety is very heterogeneous, with different regulations across countries, and different procedures for MR safety training and their application in clinical routine. The European Society of Radiology is optimally positioned to play an active role in the harmonization of MR safety education and practices across Europe, and we are proposing a four-tiered framework for the development of a teaching curriculum for MR safety training.

CRITICAL RELEVANCE STATEMENT

There is room for raising awareness of MR safety issues to ensure patient safety, reduce accidents, and benefit more patients. We advocate for radiologist-led standardization and improvement of MR safety training as a way to address this problem.

KEY POINTS

Our survey of MR safety practices across Europe revealed significant heterogeneity in regulations, training, and scanning practices. There is a widespread lack of awareness and implementation of MR safety guidelines and diffuse uncertainty, under-scanning of eligible patients, and preventable accidents. The ESR proposes a harmonized, four-tiered MR safety training curriculum to standardize, and improve safety practices across Europe.

Novel Use of Motor-Evoked Potential Monitoring During Magnetic Resonance Imaging-Guided Soft-Tissue Cryoablation: A Case Report

Motor-evoked potential (MEP) monitoring is an electrophysiologic technique useful for testing peripheral motor nerve integrity during cryoablation cases with risk of nerve injury. Previously, neuromonitoring within the magnetic resonance imaging (MRI) suite for cryoablation has not been performed as magnetic needles are used which could cause magnetic field interactions with neuromonitoring leads. We present the first report of a patient who underwent MEP monitoring during MRI-guided cryoablation of a vascular malformation adjacent to the brachial plexus. We demonstrate that MEPs may be safely and accurately performed by interleaving MRI and MEPs during treatment, reducing the risk of postprocedural complications.

Ultrasound-Guided Sacral Erector Spinae Plane Block: A Feasible Option for Pain Management During Magnetic Resonance Imaging: A Case Report

Inability to remain motionless owing to pain during magnetic resonance imaging (MRI) may increase the need for sedation and analgesia. Here, we present a case where ultrasound-guided sacral erector spinae plane block (ESPB) was used successfully for pain management during an MRI in a patient suffering from severe sacral pain. Sacral ESPB was performed with a total of 30 mL of 0.25% bupivacaine at the level of the intermediate sacral crest. The patient achieved sensory block in the L5-S4 dermatomes without motor block, resulting in complete pain relief. This case report highlights the feasibility of ultrasound-guided sacral ESPB as a potential pain management technique.

Provision of Safe Anesthesia in Magnetic Resonance Environments: Degree of Compliance with International Guidelines in Saudi Arabia

BACKGROUND

The lack of local guidelines and regulations for the administration of anesthesia in magnetic resonance imaging (MRI) units presents a potential risk to patient safety in Saudi Arabia. Hence, this study aimed to evaluate the extent to which hospitals in Saudi Arabia follow international guidelines and recommendations for the safe and effective administration of anesthesia in an MRI environment.

METHODS

This study used a questionnaire that was distributed to 31 medical facilities in Saudi Arabia that provided anesthesia in MRI units.

RESULTS

The findings of the study revealed that the mean compliance with the 17 guidelines across the 31 sites was 77%; 5 of the 31 sites (16.1%) had a compliance rate of less than 50% with the recommended guidelines. Only 19.4% of the institutes provided general safety education. Communication breakdowns between anesthesia providers and MRI teams were reported.

CONCLUSIONS

To conclude, this survey highlights the status of anesthesia standards in Saudi Arabian MRI units and emphasizes areas that require better adherence to international guidelines. The results call for targeted interventions, including the formulation of specific national anesthesia guidelines for MRI settings. Communication breakdowns between anesthesia providers and MRI teams were reported at a rate of 83.9% during the administration of a gadolinium contrast agent. There were additional breakdowns, particularly for high-risk patients with implants, such as impaired respirators (74.2%), thus requiring further investigation due to potential safety incidents during MRI procedures. While considering the limitations of this study, such as potential biases and the low response rate, it provides a valuable foundation for refining protocols and promoting standardized practices in Saudi Arabian healthcare.

Performance of Cardiac MRI in Pediatric and Adult Patients with Fontan Circulation

Cardiac MRI has become a widely accepted standard for anatomic and functional assessment of complex Fontan physiology, because it is noninvasive and suitable for comprehensive follow-up evaluation after Fontan completion. The use of cardiac MRI in pediatric and adult patients after completion of the Fontan procedure are described, and a practical and experience-based cardiac MRI protocol for evaluating these patients is provided. The current approach and study protocol in use at the authors' institution are presented, which address technical considerations concerning sequences, planning, and optimal image acquisition in patients with Fontan circulation. Additionally, for each sequence, the information that can be obtained and guidance on how to integrate it into clinical decision-making is discussed. Keywords: Pediatrics, MRI, MRI Functional Imaging, Heart, Congenital © RSNA, 2022.

Cost-effectiveness analysis of sedation and general anesthesia regimens for children undergoing magnetic resonance imaging in Japan

PURPOSE

The anesthesiologist-directed sedation service has not been well established in Japan partly due to reimbursement issue. In this study, we compared the cost-effectiveness of sedation by non-anesthesiologists with that of sedation or general anesthesia by anesthesiologists under the Japanese medical fee schedule.

METHODS

We conducted a single-center observational study with patients who required sedation or general anesthesia for magnetic resonance imaging (MRI) during a 12-month period. Costs per patient and failure rates of imaging were modeled in a decision analysis tree with sensitivity analysis. Costs were estimated from the health-care sector perspective.

RESULTS

A total of 1546 patients were analyzed. The failure rate of sedation by non-anesthesiologists was 17.5% (264 out of 1506), whereas all the sedation and general anesthesia by anesthesiologists were successful. The cost-effectiveness analysis with setting successful sedation as outcomes showed that the mean cost per patient was 84.2 USD for sedation by anesthesiologists, followed by 74.2-92.7 USD for intravenous sedation by non-anesthesiologists, 112.1-458.3 USD for oral or rectal sedation by non-anesthesiologists, and 605.4 USD for general anesthesia by anesthesiologists. The one-way sensitivity analysis demonstrated that the cost per patient of sedation by a non-anesthesiologist would remain higher than that of sedation by an anesthesiologist, provided that the failure rate is over 11.3% for sedation via oral or rectal route, or over 3.6% for intravenous route, respectively.

CONCLUSIONS

Anesthesia-directed sedation would be more cost-effective than oral or rectal sedation by non-anesthesiologists for children undergoing MRI in the Japanese medical fee schedule.

Transforming a pre-existing MRI environment into an interventional cardiac MRI suite

Aims

To illustrate the practical and technical challenges along with the safety aspects when performing MRI‐guided electrophysiological procedures in a pre‐existing diagnostic magnetic resonance imaging (MRI) environment.

Methods and Results

A dedicated, well‐trained multidisciplinary interventional cardiac MRI team (iCMR team), consisting of electrophysiologists, imaging cardiologists, radiologists, anaesthesiologists, MRI physicists, electrophysiological (EP) and MRI technicians, biomedical engineers, and medical instrumentation technologists is a prerequisite for a safe and feasible implementation of CMR‐guided electrophysiological procedures (iCMR) in a pre‐existing MRI environment. A formal dry run “mock‐up” to address the entire spectrum of technical, logistic, and safety issues was performed before obtaining final approval of the Board of Directors. With this process we showed feasibility of our workflow, safety protocol, and bailout procedures during iCMR outside the conventional EP lab. The practical aspects of performing iCMR procedures in a pre‐existing MRI environment were addressed and solidified. Finally, the influence on neighbouring MRI scanners was evaluated, showing no interference.

Conclusion

Transforming a pre‐existing diagnostic MRI environment into an iCMR suite is feasible and safe. However, performing iCMR procedures outside the conventional fluoroscopic lab, poses challenges with technical, practical, and safety aspects that need to be addressed by a dedicated multi‐disciplinary iCMR team.

Recommendations for standards of monitoring during anaesthesia and recovery 2021: Guideline from the Association of Anaesthetists

This guideline updates and replaces the 5th edition of the Standards of Monitoring published in 2015. The aim of this document is to provide guidance on the minimum standards for monitoring of any patient undergoing anaesthesia or sedation under the care of an anaesthetist. The recommendations are primarily aimed at anaesthetists practising in the UK and Ireland, but it is recognised that these guidelines may also be of use in other areas of the world. Minimum standards for monitoring patients during anaesthesia and in the recovery phase are included. There is also guidance on monitoring patients undergoing sedation and during transfer. There are new sections specifically discussing capnography, sedation and regional anaesthesia. In addition, the indications for processed electroencephalogram and neuromuscular monitoring have been updated.

Preoperative Magnetic Resonance Image Quality in Motion Disorder Patients Scheduled for Deep Brain Stimulation Surgery

BACKGROUND

To obtain magnetic resonance (MR) images of good quality for accurate target localization in deep brain stimulation (DBS) surgery, sedation or anesthesia may be used, although their usefulness has not been proven.

OBJECTIVE

To assess whether sedation or general anesthesia (GA) improve the quality of MR imaging (MRI).

METHODS

The records of DBS procedures for Parkinson's disease (PD), dystonia, and essential tremor in our tertiary neurosurgical unit between January 2011 and June 2016 were reviewed. Adult patients with preoperative MR images were included. Patient records concerning MRI, surgery, adverse events, and clinical outcome were retrospectively scrutinized and analyzed. MR image quality was assessed by two independent radiologists.

RESULTS

A total of 215 preoperative MR images for 177 DBS procedures were analyzed. The MRI sequences performed under GA were superior to those performed without anesthesia or under sedation (p < 0.01). Virtually all images captured under GA were of good quality, while the proportions among those captured with sedation or without anesthesia were <65%. Good image quality was not associated with better clinical outcome (>50% improvement in the Unified Parkinson's Disease Rating Scale III score) among patients with PD.

CONCLUSION

GA was associated with better MRI sequences than intravenous sedation or no anesthesia.

Phenytoin versus fosphenytoin for second-line treatment of status epilepticus: propensity score matching analysis using a nationwide inpatient database

PURPOSE

For status epilepticus, the choice of antiepileptic drugs for second-line treatment after benzodiazepine remains controversial: phenytoin or fosphenytoin are recommended, however, it has been unknown which is better. Using a nationwide database, we compared the efficacy and safety of them.

METHOD

An observational study conducted with the Japanese Diagnosis Procedure Combination inpatient database identified adult patients who had been admitted for status epilepticus and who had received intravenous diazepam on the day of admission from January 1, 2011 through December 31, 2015. Propensity score matching was applied to compare outcomes of the phenytoin and fosphenytoin groups.

RESULTS

The analysis examined data of 5265 patients: 2969 patients received phenytoin; 2296 received fosphenytoin, on the day of admission. One-to-one propensity score matching created 1871 matched pairs. No significant difference was found for vasopressor use on the day of admission (4.2 % vs. 4.4 %; odds ratio 1.07; 95 % confidence intervals 0.77-1.48; p = 0.69), or for mechanical ventilation on the day of admission, in-hospital mortality, length of hospital stay, or total hospitalization cost. Higher age, comorbidity of cardiac diseases and lower body mass index were associated significantly with increased vasopressor use, whereas the dose of phenytoin equivalents and the choice of fosphenytoin were not.

CONCLUSIONS

This nationwide observational study found no evidence that fosphenytoin provides higher efficacy or safety than phenytoin for treatment of status epilepticus in adults after diazepam. Age, cardiac disease and low body mass index were identified as independent risk factors for vasopressor use in both phenytoin and fosphenytoin.

Neuroanesthesiology Update

This review is intended to provide a summary of the literature pertaining to the perioperative care of neurosurgical patients and patients with neurological diseases. General topics addressed in this review include general neurosurgical considerations, stroke, neurological monitoring, and perioperative disorders of cognitive function.