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The COVID‐19 pandemic has brought some additional communicable disease considerations to the forefront in ways that have changed systems’ approaches. There are clear risks to health care practitioners during care for potentially or actually infected patients. Health care workers are already the highest‐risk profession for contracting the disease due to proximity to patients and exposure, with paramedics being among the most vulnerable [88]. The World Health Organization, the AHA, and the Centers for Disease Control and Prevention defined several aerosol‐generating procedures for which clinicians need to wear aerosol level PPE, comprising face shield or goggles, N95 mask, gown and gloves [89, 90]. These were defined as:

 open suctioning of airways

 sputum induction

 cardiopulmonary resuscitation

 endotracheal intubation and extubation

 non‐invasive ventilation (e.g., bi‐level positive or continuous positive airway pressure)

 bronchoscopy

 manual ventilation.

Procedures in which there was uncertainty about the potential for spread of infection included nebulization and high‐flow oxygen delivery. Although a systematic review was unable to find enough evidence to estimate the risk of chest compressions or defibrillation in relation to aerosol generation, guidelines have incorporated aerosol PPE for cardiac arrest resuscitation once a first attempt at defibrillation has been made [91].

Changes in advanced cardiac life support processes are primarily based on the risk associated with aerosol‐generating procedures. The first is early decision making about the need and appropriateness for continuing resuscitation, which is now recommended before transfer of a patient with OHCA into the emergency department. Factors may include age, comorbidities, and severity of illness [90]. Futile resuscitation attempts should be terminated in the field to limit the exposure of health personnel as much as possible, although this may be challenging. Some EMS guidelines have mandated that field termination of resuscitation should be considered immediately for patients with an initial rhythm of asystole or pulseless electrical activity, or after four rounds of CPR [92]. Similarly, they have indicated that return of spontaneous circulation should be sustained for at least 5 minutes, with a palpable pulse present and systolic blood pressure greater than 60 mmHg, before transporting the patient.

Airway management is a key consideration in controlling exposures during cardiac arrest resuscitative efforts for patients with a risk of COVID‐19 infection. As the prevalence of the disease is unknown in most locations, all patients should be treated as if they are high risk. When BLS is being carried out, either a facemask or cloth covering the mouth and nose of both rescuer and patient may reduce the risk of transmission, and guidelines suggest that passive oxygenation using a facemask set on 10 L/min is a useful addition [80, 83]. Some EMS guidelines have recommended the use of a non‐rebreather mask set on 6 L/min and a surgical mask placed over the mask [92]. When self‐inflating bag‐valve‐mask ventilation is considered necessary, there should be a tight seal to the face ideally maintained by a two‐handed grip, and a compression : ventilation ratio of 30 :2 delivered with the rescuer on chest compressions turning to squeeze the bag [80, 83].

Although the 2015 ILCOR guidelines suggested that bag‐valve‐mask ventilation, supraglottic airway, or tracheal intubation were all acceptable, potential COVID‐19 infection now means that tracheal intubation should be performed as soon as possible by the most experienced operator, to minimize complications and time spent exposed to aerosols. Video laryngoscopy is recommended if available, and chest compressions should be paused for intubation attempts. Once a cuffed tube is successfully inserted and a closed circuit has been established, any disconnection should be minimized, and waveform capnography should be used to monitor endotracheal tube placement and CPR quality. Positive pressure ventilation should only be delivered, if possible, after a tracheal tube has been inserted with the cuff inflated, a high‐efficiency particulate air filter connected, and correct placement confirmed.

Defibrillation is not considered an aerosol‐generating procedure, and AHA guidelines suggest that single shocks be delivered as part of the standard advanced cardiac life support algorithm. However, UK and European guidelines advise the use of three stacked shocks at the start of the algorithm, while waiting for other team members to don aerosol PPE [81, 93]. In 2015 ILCOR advised the use of single shocks in order to minimize interruptions in chest compressions [86]. However, as CPR is recognized as an aerosol‐generating procedure and defibrillation is not, it seems reasonable to attempt to treat a shockable rhythm as vigorously as possible while still maximizing rescuer protection.

Reversible causes of cardiac arrest should be sought and treated, bearing in mind that a patient may have had a cardiac arrest because of COVID‐19, or for other reasons while still being infected with the coronavirus. If treatable reversible causes of cardiac arrest have been addressed, stopping CPR early should be considered [81].

At the end of resuscitation attempts, all personnel should remove the PPE carefully and perform hand hygiene. EMS personnel should observe each other while removing PPE to monitor for possible breaches in infection control procedures [83].

Concerns about ALS delivery during the era of COVID‐19 have centered largely on airway management, undoubtedly providing important lessons for the future. In the case of cardiac arrest, however, there remains conflicting evidence about the benefits of various airway management strategies (see Chapter 13). For example, a Japanese study of 650,000 OHCA patients revealed that conventional bag‐valve‐mask ventilation was associated with better odds of neurologically favorable survival compared with any advanced airway [94]. Inconsistent conclusions among research studies result in challenges when developing systematic approaches to new considerations, such as risks associated with COVID‐19.