Purpose

To provide guidelines for safe functioning of neurophysiology laboratories during the COVID-19 pandemic, recommendations are based on expert opinion and review of relevant published guidelines. These guidelines are not intended to replace institutional, regional, or provincial protocols.

Background

Named “Severe Acute Respiratory Syndrome (SARS)-CoV-2” by the Coronaviridae Study Group, the coronavirus causing the current pandemic is responsible for the third outbreak of acute respiratory syndrome in the last two decades after the SARS in 2003 and the Middle East Respiratory Syndrome (MERS) in 2012. ²⁰ The disease caused by this coronavirus is known as “COVID-19” and the full spectrum of its symptomatology and pathophysiology is yet to be defined. As its name implies, the respiratory symptoms (cough, fever, and dyspnea) are present in more than 60% of hospitalized patients and are the main cause of death. ^{Reference Argenziano, Bruce and Slater21} It is clear that staff in the neurophysiology laboratory will be exposed to COVID-19 due to the nature of this disease. The reported neurological manifestations include a wide range of symptoms and signs such as headaches, anosmia and ageusia, impaired consciousness, toxic-metabolic encephalopathy, encephalitis, seizures and status epilepticus, strokes and vascular events, Guillain–Barré syndrome, myositis, and peripheral nerve disorders. ^{Reference Zubair, McAlpine, Gardin, Farhadian, Kuruvilla and Spudich22}

The current ongoing Canadian provincial plans to re-launch the economy are at different levels of complexity in each province. However, some have already announced the re-opening of regulated health profession services and some have scheduled non-urgent surgeries as long as they continue to follow approved guidelines set by their professional colleges. ²³

These developments have led the Canadian Society of Clinical Neurophysiologists (CSCN), the Canadian Association of Electroneurophysiology Technologists, the Association of Electromyography Technologists of Canada, the Board of Registration of Electromyography Technologists of Canada, and the Canadian Board of Registration of Electroencephalograph Technologists to elaborate this guideline for safe practice in the neurophysiology laboratories of Canada.

General Infection Control Recommendations (Table 1)

Booking of patients for neurophysiology testing should be prudent and minimize unnecessary testing. If the test will not change clinical management, avoid an emergency department visit, or avoid morbidity and mortality it should in general be deferred. During crisis or peak periods of the pandemic, only cases that are urgent or time-sensitive should be seen, such as those posing threat to life, limb, or long-term outcome. ^{Reference Liang1,Reference Bonner and Davidson2} As the pandemic starts to come under control and laboratories gain greater experience with safely seeing patients, the threshold for selecting appropriate patients for neurophysiological testing will become progressively lower. ^{Reference Desai, Kassardjian and Del Toro3–Reference Sethi6} Patient workflow should still be adjusted in order to assess high-risk cases safely. ^{Reference Liang1,Reference Desai, Kassardjian and Del Toro3} In COVID-19-positive cases, neurodiagnostic testing should be performed only in the inpatient setting with full personal protective equipment (PPE) equipment as per local protocols, only if test results will change management (treatment and/or diagnosis), and ideally in an airborne infection isolation room (AIIR) as the virus could survive several hours to days on certain surfaces. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Ather, Mirza and Edemekong7} If done in AIIR, these tests should be postponed for at least 4 h if recent aerosol generating medical procedure (AGMP) had been performed (i.e., nebulizer therapy, chest physiotherapy, intubation, bronchoscopy, sputum induction, bilevel positive airway pressure [BiPAP], or continuous positive airway pressure [CPAP] use). ^{Reference Haines, Caccamo, Chan, Galaso, Catinchi and Gupta5,Reference Ather, Mirza and Edemekong7} The outpatient setting is reserved for COVID-19-negative patients when triaging deems necessary. ^{Reference Desai, Kassardjian and Del Toro3-Reference Sethi6,Reference Kassardjian, Desai and Narayanaswami8}

Table 1: General infection control recommendations ^{Reference Liang1–Reference Li, Samaranayake, Leung and Neelakantan13}

The waiting room must be utilized in a way that will allow a 2-m gap (physical distancing) between patients, including not concomitant bookings if needed due to limited physical space. ^{Reference Liang1-Reference San-Juan, Jiménez and Camilli4,Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9} Electroencephalogram (EEG) and electromyogram/nerve conduction study (EMG/NCS) technologists must avoid remaining in the waiting room to minimize physical contact with patients. There should be sufficient time between appointments to allow for distancing arrangements and the cleaning of equipment. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4} If multiple clinics running simultaneously share the waiting room, staff should consider the implications of a large volume of patients in shared spaces, including corridors. ^{Reference Liang1} Special attention should be paid to patients requiring escorts (i.e., pediatric or with disabilities). These patients’ requisitions should be flagged in order to be identified in advance and account for the extra space needed in the waiting room. Prohibiting visitors and family members from attending the visit unless necessary is encouraged. The use of a clinical and epidemiological screening tool looking for high-risk patients prior to confirming the appointment and right before proceeding with the test (if done on a different date) is recommended. ^{Reference Liang1,Reference Desai, Kassardjian and Del Toro3,Reference San-Juan, Jiménez and Camilli4} Everyone, including all health care workers (HCWs), patients, and visitors, should be considered as potential carriers of COVID-19 in order to minimize risks. ^10,11

Laboratory staff must be screened with a fit for work screening tool or questionnaire on a regular basis, preferable on a daily basis, to prevent institutional spreading of the infection. ^{Reference Liang1,10,11} They should adhere to all guidelines for physical distancing, isolation, or quarantine if required. Appropriate precautions, as dictated by local infection prevention and control (IPAC) leaders, should be used at all times at work. ¹¹ Considerations for limiting technologist exposure to high-risk patients include limiting tests to only as long as absolutely necessary for a clinical decision, reducing inpatient technologist coverage hours, implementing alternate technologist shifts, identifying experienced technologists to manage challenging cases, and delaying testing until such expertise is available (although caution may be required for technologists over 60 years of age), considering mitigating factors (i.e., pregnancy, immunodeficiency, and living with elders), and providing resources for technologist counselling. ^{Reference Liang1-Reference San-Juan, Jiménez and Camilli4,Reference Sethi6} Laboratory leaders should reinforce that appropriate use of recommended equipment and processes will protect staff. They should also minimize personal displays of fear or anxiety that are not productive or helpful. ^{Reference Bonner and Davidson2}

Re-triaging and prioritization of all cancelled or postponed patients is important including updates of the current status on their clinical conditions to confirm whether the test is still necessary or if an upgraded triage score is needed. Inpatients and after hours requests should be triaged by the attending neurologist on service or on-call – not a designate. Triaging of outpatient requests should be done by the laboratory director or a designate approved by the laboratory director. Patients must have appropriate notification on file and on the test requisition of confirmed or suspected COVID-19 infection to alert laboratory staff. ^{Reference Bonner and Davidson2-Reference San-Juan, Jiménez and Camilli4}

PPE occupies a key role in preventing infection and dissemination of the disease. Three different tiers of facial masks are available including respirator masks (N95 and FFP2 variants) with higher filtering capacity particularly in aerosol-generating procedures. The second tier include the surgical masks which are classified into three levels according to their filtration efficacy. They offer protection against droplets from direct spatter although they are not as effective as the previous category for small particles. There is a variant of these masks which includes eye plastic shield increasing the protection capabilities. Finally, single-use masks may be made of a single layer and are not used in the healthcare setting as they can control mainly large volume of saliva emission. Two other elements for facial protection are available. Facial shields provide an additional physical barrier and could be utilized along with the previously mentioned masks to minimize risks. Powered air-purifying respirators are mainly used in dentistry practice. The last two options should be considered for high-risk procedures. ^{Reference Garcia Godoy, Jones and Anderson12,Reference Li, Samaranayake, Leung and Neelakantan13} Surgical facial masks (preferable with plastic eye shield) and gloves should be used by the patient, escorts, technologists, physicians, and trainees at all times during the duration of the encounter. In select circumstances, N95 masks may be used if deemed appropriate (i.e., single-fiber EMG [SFEMG] in facial muscles and confirmed COVID-19-positive patient). ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9} Disposable or reusable PPE and biohazard waste management must follow well-known recommendations (i.e., Government of Canada, Center of Disease Control). Please refer to their websites for further details as it is beyond the scope of this document. ^10,11 Staff should be trained in PPE use. ^{Reference Bonner and Davidson2}

Equipment and testing rooms must be cleaned, disinfected, and sanitized at the beginning of the working day and after every patient tested. Minimal handling of equipment and testing materials is also desirable in order to minimize the possibilities of contamination. Consider the use of dedicated NCS/EMG/EEG/evoked potential (EP) equipment for high-risk areas and/or positive/probable cases with COVID-19. ^{Reference Bonner and Davidson2,Reference Ather, Mirza and Edemekong7} Strict cleaning procedures, that follow local IPAC guidance, should include but are not limited to ^{Reference Liang1–Reference Kassardjian, Desai and Narayanaswami8} :

• Cleaning all surfaces patients touch (beds, linens, chairs, doorknobs, grab bars, etc.)

• Cleaning all surfaces staff touch (keyboards, carts, cables, etc.)

• Disposable items should be used whenever cleaning is not feasible.

• If not disposable, consider covering ancillary equipment pieces in disposable single-use clear medical grade plastic, especially if equipment (e.g., jackboxes) is located close to the patient.

• Consider consulting the manufacturers of NCS/EMG/EEG/EP units to ensure surface disinfectants used are compatible with the external hardware of the units and do not pose a risk of compromising equipment.

• The EEG equipment will usually require cleaning of the amplifier (headbox), computer – keyboard, cables – wires, particularly if these are non-disposable. Extra time is needed for the disinfectant to air dry. This procedure usually takes extra 15–30 min per patient of the regular 75–90 min appointment.

• Cleaning of an EMG/NCS equipment may be quicker as most items making contact with the patient are disposable. An additional 15 min for cleaning/disinfecting should suffice.

Clinicians may want to consider providing some part of the care via virtual platforms such as initial history taking, discussion of results, and/or follow-up visits.

EMG/NCS Specific Recommendations (Table 2)

In general, EMG/NCS in the setting of COVID-19 requires focus on the prevention of spread through contact and droplets, in addition to the usual body fluid precautions. Unless there is an AGMP in process (e.g., a patient is intubated, or on CPAP, or BiPAP,) or facial SFEMG is performed, there is no need for N95 masks and eyes protection. ^{Reference Bonner and Davidson2-Reference San-Juan, Jiménez and Camilli4} Although performing facial SFEMG is not considered an aerosolization maneuver, due to the proximity to involuntary sources of rapid exhalation (i.e., cough and sneeze) and the length of time exposed to the patient, a preference for using an N95 mask and facial shield or goggles seems reasonable based on individual risk assessment at the time. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Kassardjian, Desai and Narayanaswami8,Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9} Surgical masks (preferable with plastic eye shield) should be considered when performing peripheral EMG/NCS in COVID-19-negative patients; however, in COVID-19-positive patients, due to the potential aerosolization of the virus in the room, N95 mask and facial shield or goggles should be used. ^{Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9,Reference Garcia Godoy, Jones and Anderson12,Reference Li, Samaranayake, Leung and Neelakantan13} Testing should be performed as many hours after an AGMP was performed as possible (preferable after 4 h). ^{Reference Sethi6,Reference Ather, Mirza and Edemekong7} Both patient and HCWs should have PPE appropriate for the prolonged, close contact. ^10,11

Table 2: EMG/NCS specific recommendations ^{Reference Bonner and Davidson2–Reference San-Juan, Jiménez and Camilli4,Reference Sethi6–Reference Li, Samaranayake, Leung and Neelakantan13}

Testing should be the minimum requirement for diagnosis and management. This will minimize in person contact. Measures should be taken to reduce the risk of patient-to-patient transmission such as doing inpatient studies on the wards instead of bringing patients to the lab. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4}

When time-sensitive interventions or diagnostic accuracy is hinging upon EMG/NCS, these should be prioritized and performed using appropriate precautions. ^{Reference Kassardjian, Desai and Narayanaswami8} Examples of such situations include patients who may be candidates for nerve transfers, patients with rapidly progressive deficits (e.g., suspected Guillain–Barré syndrome), patients in whom definitive diagnosis is required for treatment (e.g., generalized myasthenia gravis when the wait for serology results could be prolonged), or patients waiting for confirmation of serious conditions (e.g., suspected amyotrophic lateral sclerosis). When there is uncertainty about the urgency of a particular referral, then consideration should be given to contacting the referring physician and obtaining further information.

EEG and EMU Specific Recommendations (Table 3)

The decision to use collodion versus paste and tape must consider possible aerosolization risk with collodion application against the need to reapply paste and tape electrodes from poor adherence. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Sethi6} The length of the study should be short enough to address the patient management and at the same time to minimize the exposure of the technologist to a high-risk patient maintaining the minimal standards. ^{Reference San-Juan, Jiménez and Camilli4,Reference Haines, Caccamo, Chan, Galaso, Catinchi and Gupta5} Hyperventilation should not be routinely performed, but if justified for high diagnostic yield (e.g., pediatric absence epilepsy), patients must wear surgical masks. ^{Reference San-Juan, Jiménez and Camilli4-Reference Sethi6}

Table 3: EEG, neurostimulation, and EP specific recommendations ^{Reference Bonner and Davidson2–Reference Ather, Mirza and Edemekong7,Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9,Reference Garcia Godoy, Jones and Anderson12}

SUDEP = sudden unexpected death in epilepsy; SPECT = single-photon emission computed tomography.

Utilization of surgical mask and goggles or N95 and facial shield should be considered for inpatients when in the ward or intensive care units (ICUs), respectively. In COVID-19-positive patients, the second facial protection combination is preferred. ^{Reference Ather, Mirza and Edemekong7,Reference Chu, Akl, Duda, Solo, Yaacoub and Schünemann9,Reference Garcia Godoy, Jones and Anderson12,Reference Li, Samaranayake, Leung and Neelakantan13} Inpatient/continuous EEG should situate the portable video-EEG system outside the patient room using long cables if safe and necessary, particularly if COVID-19 positive or if the physical space in the epilepsy monitoring unit (EMU) room does not allow to place the EEG machine 2 m apart from the patient. ^{Reference San-Juan, Jiménez and Camilli4} The number of different technologists entering each patient room should be limited. Stimulation for reactivity assessment can still be performed. Recordings should last at least 20 min, but may be delayed by at least 4 h to reduce potential airborne transmission if there has been nebulizer treatment. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Sethi6}

Prior to EMU reopening, ensure adequate staffing and rescue medications, mask and COVID-19 testing availability, limiting patient breaks, available ICU beds for post-operative care and status epilepticus, and physical distance from COVID-19 areas. Rounds and surgical conferences should be virtualized, with consideration to additional operations and business meetings to review lists of previously cancelled/held admissions, new admissions, and intracranial subdural/stereo-EEG/electrocorticography logistics. ^{Reference San-Juan, Jiménez and Camilli4,14} Admissions should consider whether nasal/oropharyngeal swab for rapid COVID-19 testing is deemed necessary as an early infection detection could prevent further contagious disease. ^{Reference Lagier, Colson and Tissot Dupont15} Consideration should be present for allowing family members in the EMU if needed for safety and diagnostic accuracy. Priority indications may include potential for management changes based on monitoring, pre-surgical workup (phase I, II, and ictal single-photon emission computed tomography), high seizure burden, sudden unexpected death in epilepsy risk, threat of disease worsening, and frequent emergency department visits. ¹⁴ To avoid cross-contamination between hospital populations, EMUs should be populated by persons with, or suspected to have, epilepsy. EMUs may also consider initially reopening at half capacity with physical distancing and enhanced barrier protection measures (e.g., plastic over curtains). ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,14}

As a possible EMU alternative, ambulatory EEG should include video, ideally with outpatient dis/connection external to hospital, plastic covering for community COVID-19 settings, and allowing a “rest period” between uses for potentially difficult to disinfect ambulatory pieces (e.g., pouches and straps), while keeping in mind battery limitations. ^{Reference San-Juan, Jiménez and Camilli4-Reference Sethi6,14}

Neurostimulation (Table 3)

If stable, consider using virtual visits and deferring programmatic changes, with alternatives such as optimizing anti-seizure medications and instituting a rescue medication strategy. While vagus nerve stimulator (VNS) auto-titration and deep brain stimulation (DBS) program sets allow automated changes, decompensation may occur in remote settings, and surgical procedures may be limited even in urban centres. The need for in-person programming/evaluation should consider factors such as status epilepticus, increased seizures, seizure-related injuries, severe stimulation-related side effects, battery depletion, non-superficial hardware infection, and hardware malfunction on a case-by-case basis. ^{Reference Gross, Buetefisch and Miocinovic16}

EP Specific Recommendations (Table 3)

Consult the manufacturer of goggles and headphones to ensure surface disinfectants used are compatible with the external hardware and do not pose a risk of compromising equipment or patient care. If using earbuds or inner ear electrodes for sound generation, they must be discarded after each use. ^{Reference San-Juan, Jiménez and Camilli4} When somatosensory EPs are needed in the ICU setting, assess whether the patient poses a risk of aerosol-generating procedures and ensure adequate PPE is used according to your facilities’ recommendations; N95 mask may be necessary in these cases. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Ather, Mirza and Edemekong7}

IOM Specific Recommendations

Patients with active infectious disease, including COVID-19, or those on droplet or contact precautions are unlikely to undergo surgery requiring intraoperative monitoring, unless it is deemed medically emergent. ^{Reference San-Juan, Jiménez and Camilli4,Reference Macdonald, Deletis and Nuwer17} In these cases, consideration of aerosol-generating procedures such as intubation or cautery should determine the appropriate PPE required and the safe distance from the patient. ^{Reference Bonner and Davidson2,Reference San-Juan, Jiménez and Camilli4,Reference Macdonald, Deletis and Nuwer17} Only sterile single-use needle and corkscrew electrodes should be used. Surface electrodes should be single-use and discarded after use. ^{Reference Macdonald, Deletis and Nuwer17} Remote monitoring could reduce exposure to the neurophysiologist or technologist. ^{Reference San-Juan, Jiménez and Camilli4,Reference Macdonald, Deletis and Nuwer17}

Future Directions (Table 4)

The COVID-19 pandemic has created opportunities for innovation and potential improvement in delivery of diagnostic testing and care for patients with neurological disorders. The remote clinical practice is now a global reality. Clinicians may consider providing some part of their electrophysiological care via phone or virtual platforms where internet or cellphone network is accessible. This could include screening of referrals, initial history taking, discussion of results with either patients or other health care personnel, seeking second opinions, team management meetings, and/or follow-up visits. ^{Reference Roy, Nowak and Roda18,Reference Hatcher-Martin, Adams and Anderson19}

Table 4: Future directions ^{Reference Roy, Nowak and Roda18,Reference Hatcher-Martin, Adams and Anderson19}

The development or revision of local guidelines on appropriate referral criteria for neurodiagnostic studies could optimize the use of clinical neurophysiology resources, minimizing unnecessary testing and prioritizing studies that otherwise could have been delayed due to saturation of the health system. Local guidelines could also address the need for and frequency of follow-up studies in those cases where neurophysiological studies are the only objective way to measure improvement of medical or surgical interventions. ^{Reference Roy, Nowak and Roda18,Reference Hatcher-Martin, Adams and Anderson19}

Validation of the utility and the cost-effectiveness of remote–virtual care needs further assessment. The lack of reported data on the pros and cons of virtual care in neurophysiology in comparison to in-person visits merits further assessment in the field.

These guidelines may also serve as a useful reference in the case of future pandemics. Eventual resolution of the pandemic or the development of successful therapy for COVID-19 may make these guidelines obsolete. However, in the meantime, following the above recommendations is crucial to minimize the spreading of COVID-19. Revised versions will be made available on the CSCN website.