Controlling exposure to COVID-19 is critical for protection of health care workers. This can be represented by a hierarchy of controls. Engineering controls are designed to remove the hazard at the source before it comes in contact with the worker. Administrative controls and Personal Protection Equipment (PPE) are frequently used with existing processes where hazards are not particularly well controlled. Safety of staff is paramount to protect the individual health care worker and to ensure a viable workforce for the duration of the pandemic.
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In Australia, the national infection control standards are the national standard AS/NZS 1715: 2009 and National Health and Medical Research Council, Australian Guidelines for the Prevention and Control of Infection in Healthcare (NHMRC, 2019). There are extensive national and jurisdictional COVID-19 guidelines and resources. (Australian Government Department of Health, 2020).
There are three commonly accepted modes of viral transmission:
1. Direct contact with contaminated surfaces (fomites)
2. Larger respiratory droplets
3. Smaller micro-droplets known as aerosols.
In the context of SARS-CoV2, there is increasing evidence for airborne transmission. In 2020 healthcare workers constituted a substantial proportion of all COVID-19 infections in Australia, and data suggests that the majority of HCWs acquired it at the workplace. HCW infections lead to infection in other HCWs, close contacts and patients. Subsequent staff furlough has a significant impact on workforce sustainability.
Introduction
Engineering controls are designed to remove the hazard at the source before it comes into contact with the worker and can be very effective as long as these are designed, used and maintained properly. Engineering controls include:
- Process controls – Change the way an activity or process is performed to reduce the risk of transmission.
- Enclosure and isolation – Ensures separation between the patient and the HCW.
- Ventilation – Moves outdoor air into a building or a room, and distributes the air within the building or room.
Patients are placed in higher-order engineering control areas before using lower-order areas.
Patient care areas include:
- Class N rooms are negative pressure isolation rooms used to isolate patients capable of transmitting airborne infection. A Class N room should have a functional anteroom for donning and doffing PPE. Airborne PPE precautions are still required. Doffing is performed in the anteroom. There are a limited number of negative pressure rooms across Australia and New Zealand.
- Class S rooms are standard rooms which can be used for isolating patients capable of transmitting infection by droplet or contact routes. Class S rooms have no negative pressure capability. Airborne droplets can remain in the air for up to three hours post procedure. These rooms must be reviewed by engineering to optimise airflow and air exchanges.
- Open Cohort Areas have no negative pressure capability. These areas must be reviewed by engineering to optimise airflow and air exchanges. In an open ICU cohorted area with one or more COVID-19 patients, the whole area is strongly recommended to require airborne PPE precautions with careful attention to the clear designation of safe donning and doffing areas.
We recommend COVID-19 patients ideally be treated in a Class N negative pressure single room. If Class N rooms are not available, then the preference should be Class S single rooms (with appropriate engineering and ventilation considerations) with clear areas designated for donning and doffing of PPE.
Once all Class N and Class S rooms are exhausted, then consideration could be given to moving patients to a facility with available Class N or Class S rooms. If not possible, patients will need to be cohorted in areas that are physically separate to areas containing non-COVID-19 patients.
We recommend that aerosol-generating procedures (AGP) are performed in Class N rooms. If performed in a Class S room or cohorted area, engineering controls should be optimised for rooms selected for this purpose. This should include exhausting air conditioning to an external point and at least 6, ideally 12, air exchanges per hour.
Administrative Control Considerations Related to PPE
In ICU there is an increased risk of dispersion of aerosolised virus into the healthcare environment due to the nature of critical illness, higher patient viral load and the performance of aerosol-generating procedures. We recommend contact and airborne PPE precautions be used to care for all suspected or confirmed COVID-19 patients in intensive care, including the care of patients in an open cohorted ICU. We also recommend intensive care staff adhere to contact and airborne PPE precautions for the assessment or care of suspected or confirmed COVID-19 patients in any location within the hospital. This advice is consistent with the National COVID-19 Clinical Evidence Taskforce advice on protection of healthcare workers.
We recommend that all hospitals should keep a record and report staff training in PPE compliance and competency; only staff who have been trained in PPE usage should care for patients confirmed or suspected to have COVID-19. We recommend that there is a system in place to ensure compliance with changes in PPE recommendations.
We recommend fit testing of N95 masks. The purpose of fit testing is to identify which size and style of N95 is suitable for an individual. It also provides an opportunity to ensure healthcare workers are properly trained in the correct use of the mask. If staff are unable to achieve a fit test with available N95 masks, then we recommend the staff member be redeployed. If this is not possible due to the affected staff member performing a vital function in the ICU, then the use of PAPR could be considered.
We recommend minimising aerosol generating procedures (AGP) unless these are absolutely necessary. If they must be performed, then they should be completed in a negative pressure room (Class N room). If this is not available, then a single room (Class S) should be used with the doors closed.
Aerosol generating procedures (AGP) include:
- Intubation
- Extubation
- Bronchoscopy
- High flow nasal oxygen use
- Nebulised therapies
- Non-invasive ventilation (particularly with a poorly fitting mask)
- Procedures on screaming children
- Tracheostomy
- CPR prior to intubation.
There is now recognition that Aerosol Generating Behaviours (AGBs) are an important method of transmission of COVID-19 and this reinforces the need for contact and airborne precautions in the critical care environment.
Powered Air Purifying Respirators (PAPR), with appropriate training on the use of these devices, may be considered for staff protection against COVID-19. One benefit of PAPR is they do not necessarily rely on a proper seal, thus for those conducting AGP procedures the risks associated with ill-fitting N95 masks are reduced. Although expensive, some can be disinfected and reused.
The use of PAPR helmets may free up supplies of face shields and disposable N95 masks. Donning and doffing of these devices may be complex, and the risk of viral dispersal during the doffing process must be weighed against any benefit of the device. We recommend strong attention to be given to the correct doffing procedure if these devices are used.
Airway Management
We are aware of multiple comprehensive guidelines for airway management in COVID-19 patients and we endorse the Safe Airway Society consensus statement on Airway Management and Tracheal Intubation in COVID-19 patients. We recommend the following principles for intubation of a proven or suspected patient with COVID-19 to minimise HCW infection:
- Intubation should preferentially be performed in a negative pressure room (Class N) or if not available then a single room should be used (Class S).
- We recommend airborne PPE precautions for all staff in attendance including:
- Fit checked N95 mask
- Face shield
- Impervious gown
- Gloves
- The procedure should be performed by the most qualified available staff with the minimum number of healthcare personnel present as are required to undertake a safe intubation
- Video laryngoscopes should be used preferentially, and staff should be trained and familiar with these devices
- To reduce aerosol generation staff should consider:
- Optimising pre-oxygenation to reduce the need for rescue interventions
- Use of a viral filter on bag mask circuit
- Minimising the need for bag mask ventilation unless there is significant hypoxia or acidosis
- Initiating positive pressure ventilation only after confirming that the endotracheal tube cuff is inflated and after ensuring that an appropriate filter and waveform capnography device is in place.
Extubation
We recommend the following principles for extubation of a patient with COVID-19 to minimise HCW infection and improve outcome and safety:
- Extubation should ideally take place in a negative pressure room.
- Minimise the number of staff in the room, with staff available outside the room for emergencies.
- Staff should observe airborne precautions, with appropriate PPE, at all times.
- Adequately trained staff for re-intubation should be available.
Failed extubation in COVID-19 patients is potentially a high risk situation for HCW infection. Consideration should be given to optimisation of clinical status, spontaneous breathing trials and time of day for extubation to ensure the best possibility of a successful extubation and availability of senior staff if re-intubation is needed.
Percutaneous Tracheostomy
Tracheostomy is often required to facilitate weaning from mechanical ventilation. The benefits of the procedure need to be balanced against the risk to health care workers posed by performing this aerosolising procedure. We are not aware of any evidence to guide the ideal timing of tracheostomy in COVID-19 patients, however we would recommend that tracheostomy should not be performed before 10 days of mechanical ventilation.
Cardiopulmonary Resuscitation
The recommendations pertaining to the organisation of rapid response teams are discussed in the Pandemic Planning section under Critical Care Outreach and Rapid Response, Medical Emergency and Code Blue Teams.
Cardiopulmonary resuscitation is considered an aerosol generating procedure and appropriate PPE should be worn by healthcare staff. We recommend hospitals review their approach to cardiopulmonary resuscitation (CPR) on the ward, for patients with COVID-19, as well as for the general ward population during periods of increased community transmission.
We endorse the National COVID-19 Clinical Evidence Taskforce Guidelines for Cardiopulmonary Resuscitation.
Post Exposure Management
It is recommended every observed breach in PPE usage is recorded in the incident management system as an occupational health and safety risk. ANZICS recognises that breaches will occur despite best efforts and no blame should be apportioned to the individuals involved.
If an exposure or breach of PPE occurs, assessment and risk categorisation of the staff member should be done in accordance with national guidelines and local policy. Based on risk of exposure the appropriate further management should be commenced immediately including a quarantine/self-isolation period. We recommend staff should be provided with funded accommodation if they are unable to self-isolate in their own home.
For either staff illness or post exposure management we recommend the provision of adequate psychosocial support for the staff member during quarantine or for the duration of their illness. On return to work a refresher infection control and prevention training should be offered for the staff member.
Nosocomial Health Care Worker Infection
We recommend that each nosocomial health care worker COVID-19 infection is entered into the local and jurisdictional incident management system as a notifiable major incident.
We recommend that each COVID-19 HCW infection is independently reviewed with adjudication of source and the mechanism of infection. A multi-incident analysis should identify the preventable factors and system changes to decrease HCW infections.
Psychological Needs of Healthcare Staff
During the COVID-19 pandemic, health care professionals face a rapidly evolving practice environment that differs greatly from what they were trained in. Preparing for and managing a surge in critically unwell patients has changed the way we work and interact as a team. There are societal shifts and emotional stressors faced by all people. In addition to this, ICU staff face greater risk of infection exposure, extreme workloads and moral dilemmas.
All ICU staff will experience an increased workload with heightened anxiety both at work and at home. ANZICS recognises that care of ICU staff is an important consideration to maintain sustainability and ensure we have a workforce after the pandemic has ended. The psychological needs of healthcare staff are described in Table 1.
