key: cord-0930738-lubvzg53
authors: Drum, Elizabeth; McClung Pasqualino, Heather; Subramanyam, Rajeev
title: Anesthesia and potential aerosol generation during Magnetic Resonance Imaging in Children with COVID‐19
date: 2020-06-21
journal: Paediatr Anaesth
DOI: 10.1111/pan.13951
sha: ce6e5d0680e59c74cdcad2386b274b4b1216bf28
doc_id: 930738
cord_uid: lubvzg53

The American College of Radiology recommends minimizing Magnetic Resonance Imaging (MRI) in COVID‐19 patients, postponing non‐urgent exams, and using alternative imaging.(1)Sedation/anesthesia are aerosol generating procedures (AGP) due to requirement of bag‐mask ventilation, intubation, and extubation with consequent risk of exposure to healthcare workers. This is complicated by limitation in the use of personal protective equipment (PPE) in the magnet zone (Zone IV).We describe our experience for children requiring anesthesia for emergency MRI during the COVID‐19 outbreak in Philadelphia.

The American College of Radiology recommends minimizing Magnetic Resonance Imaging (MRI) in COVID-19 patients, postponing non-urgent exams, and using alternative imaging. 1 Sedation/anesthesia are aerosol generating procedures (AGP) due to requirement of bag-mask ventilation, intubation, and extubation with consequent risk of exposure to healthcare workers. This is complicated by limitation in the use of personal protective equipment (PPE) in the magnet zone (Zone IV).We describe our experience for children requiring anesthesia for emergency MRI during the COVID-19 outbreak in Philadelphia.

This study protocol received an exempt from IRB. Between March 26, 2020 to May 11, 2020, we performed chart review to identifychildrenwithlaboratory diagnosed or probable COVID-19 who underwent MRI thatnecessitatedgeneral anesthesia.Electronic medical record query was performed for all anesthesia procedures and children who had MR procedures under general anesthesia were identified.

A total of 149 MR procedures were performed in the time period. Amongst this, we identified four children with COVID-19 who underwent emergency MRI that necessitated general anesthesia ( Table 1 ).The care of the COVID-19 patients required multi-disciplinary conversation and planning.For the management, we divided MRI into zones to reduce exposure to healthcare workers(Supplementary Figure) ,and identified themes and workflow for safe care of COVID-19 patients and healthcare workers during MRI and AGP (Supplementary Table) .Team members expected to enter Zone IV removed all ferromagnetic material prior to donning PPE. Metal screening for staff and patient were performed ahead of time. We identified a negative pressure room equipped to provide general anesthesia, used high quality viral filtration in the breathing circuit and verified the presence of anesthesia scavenging system to prevent aerosol spread. The transport path for

This article is protected by copyright. All rights reserved the patient to and from the MR area was clearly defined along with the assistance of hospital security. The PPE used 2 are reported in Table 1 .

Our routine MRI anesthesia management is with natural airway or laryngeal mask airway.

There was a change in the technique with COVID-19 patients which included airway management in a negative pressure room and expanded PPE to prevent aerosol generation.

Although surgical masksare an MR safe alternative, due to AGP this was considered insufficient. As of writing this letter, not all types of respirators are tested in the MR environment. Powered air-purifying respirators (PAPR) are likely not acceptable due to MRI safety concerns. A recent study evaluated the use of European respirators in the MR environment on a three-dimensionally printed phantom face. They found considerable force/torque in the magnetic environment that could disrupt the tight mask seal during AGP and were also regarded as MR unsafe. 3 This study did not evaluate N95 masks, which are a commonly used respirator in the USA. N95 masks consist of a metal nosepiece that could pose a hazard in the magnet zone of MRI and may not have been evaluated for MR safety.

We checked the interaction of the N95 respirator (3M, St Paul, Minnesota, USA) metal piece with the magnet by wearing it and moving into an empty MR room. There was a tug felt when the face with N95 on was close to the bore with no difference in "feel" away from the gauss line (away from the bore). Although on the basis of this alone, we cannot say if N95 is protective to the wearer in the magnet zone but the possibility of its use should be considered until further data is available.

This article is protected by copyright. All rights reserved 

American College of Radiology. ACR guidance on COVID-19 and MR use

Intubation and Ventilation amid the COVID-19 Outbreak: Wuhan's Experience

Respirators and surgical facemasks for COVID-19: implications for MRI