Updated guidance on Personal Protective Equipment (PPE) for clinicians
11 April 2020
On 2 April 2020 Public Health England (PHE) and its devolved nation equivalents released updated guidance on infection control and personal protective equipment (PPE) in the setting of the COVID-19 epidemic. A series of documents is now available here.
The documents should be read by all healthcare professionals. Here, we summarise the key messages and changes. As usual, we emphasise that PPE is only one part of a wider system to reduce the risk of viral transmission during the coronavirus epidemic and is worn while treating patients who are confirmed to have or may have COVID-19.
Mode of transmission
The position on the modes of transmission of COVID-19 has not changed. It is thought to occur mainly through respiratory droplets generated by coughing and sneezing, and through contact with contaminated surfaces. Most droplets do not travel more than 2 metres from the patient. Airborne transmission may occur when aerosols of viral material are created by aerosol generating procedure (AGPs). These may travel further and remain airborne much longer. The list of AGPs is as yet unchanged but is currently under review. Of particular note as we write, chest compressions are not considered by PHE to be AGPs, while the Resuscitation Council UK takes the view that they are. We hope that this difference of interpretation of the evidence will be resolved soon.
Widespread use of facemasks
Notwithstanding the modes of transmission described above, the guidance extends the use of facemasks by staff to all clinical areas in which there are patents who are confirmed or possible COVID-19 positive, including where there is no clinical contact, and in other locations to protect vulnerable patients who would normally be isolated. Patients who are COVID-19 positive must wear surgical masks to reduce distribution of virus.
Distance from the patient
The distance from the patient at which precautions should be escalated has been changed from 1m to 2m. This is logical.
Levels of PPE
The document provides a table in which it attempts to describe each clinical area and what PPE should be used. The table is too large to describe but the principles underlying it can be summarised thus:
more than 2 metres from the patient: wear a fluid resistant surgical face mask (FRSM) +/- eye and face protection
risk of droplet transmission (less than 2 metres from the patient but no AGPs): wear gloves, apron, FRSM and consider eye/face protection
risk of airborne transmission because an AGP being performed or in ‘hotspot’ (higher risk acute area): wear gloves, long-sleeved fluid repellent gown, eye/face protection and a respirator mask, eg FFP3 mask.
Logically if seeking to avoid contact (fomite) transmission – gloves and an apron are sensible precautions.
Hot spots
The document describes “higher risk acute inpatient care areas” that we will call “hotspots”. In these areas, AGPs are deemed so frequent that the whole area is suitable for airborne precautions at all times.
These areas include intensive care (ICU) and high dependency care (HDU) units, Emergency Department resuscitation areas, operating theatres where AGPs are performed, CPAP/High flow oxygen wards, endoscopy units undertaking bronchoscopy, upper gastrointestinal or nasendoscopy, and other clinical areas in which AGPs are regularly performed.
Sessional PPE
The concept of wearing disposable PPE for more than one patent is introduced. Gloves and aprons are always single use per patient. The session relates to a period of time spent in one location with one type of patient and would include being in an ICU or operating theatre with patients being treated as COVID-19 positive. Scrupulous washing of hands and forearms is required between patients.
Droplet precautions are made sessional by continuing to dispose of gloves and apron after each patient but retaining eye/face protection and FRSM for the whole session. Airborne precautions are made sessional by adding an apron on top of the gown and disposing of the apron and gloves between patients, while retaining eye/face protection, FFP3 mask and gown throughout the session.
Decision making as to who to treat as ‘COVID-19 confirmed or possible’
This is delegated to a local decision based on local epidemiology. The PHE document states “risk assessment at organisational level requires that organisations consider healthcare associated COVID-19 risk at local level and according to the local context. Organisational risk assessment and local guidance should not replace or reduce the ability of the health and social care worker to use appropriate PPE while providing care to patients or residents. Local acute provider risk assessment may assist in determining higher risk areas and identify specific areas of a hospital where sessional use of PPE is required (for example, certain wards, clinical areas)”.
Mask fit testing and other face fitting masks
The guidance states that “the Health and Safety Executive (HSE) state that all staff who are required to wear an FFP3 respirator must be fit tested for the relevant model to ensure an adequate seal or fit (according to the manufacturers’ guidance).” The HSE guidance is available here.
Viral clearance time after an AGP
The guidance states that when an AGP is undertaken in operating theatres the room can be cleaned after five minutes. This will likely have allowed for 1-2 air changes in a well-ventilated theatre and a reduction in viral load in the room of 63% to 86%.
The question everyone is asking
Does the new PHE guidance allow anaesthetists and others working in the operating theatres to wear “full” PPE (respirator mask, eye/face protection, long-sleeved fluid-repellent gown and gloves) for all patients they treat? The answer is “yes” but with two provisos: (A) if frequent AGPs are preformed and (B) if you believe that the prevalence of asymptomatic COVID-19 patients in your area is such that they present a threat to the health of those working in the operating theatres.
We have produced another table and list of clinical scenarios for you
The tables and scenarios are an interpretation of the latest PHE guidance and can be accessed here. Some will find this useful, but others may view it as providing no additional value. We will leave you to determine whether it is of value to you in your practice. This page was last updated on 12 April 2020.
Professor Tim Cook
Professor William Harrop-Griffiths
ENDS