From the Guidelines
It is not recommended to disconnect the ventilator prior to defibrillation (cardioversion) as this may lead to aerosolization and compromise patient safety, instead consider leaving the patient on a mechanical ventilator with a HEPA filter to maintain a closed circuit. When preparing for defibrillation, the focus should be on maintaining a closed circuit and minimizing aerosolization, as recommended by the 2022 interim guidance to health care providers for basic and advanced cardiac life support in adults, children, and neonates with suspected or confirmed covid-19 1. This approach prioritizes patient safety and reduces the risk of equipment damage or harm to healthcare providers.
- Key considerations for ventilator settings during defibrillation include:
- Increasing the FiO2 to 1.0
- Using either pressure or volume control ventilation and limiting pressure or tidal volume to generate adequate chest rise
- Adjusting the trigger settings to prevent the ventilator from auto triggering with chest compressions
- Adjusting respiratory rate to 10 breaths/min for adults, 20 to 30 breaths/min for infants and children, and 30 breaths/min for neonates
- Assessing the need to adjust the positive end-expiratory pressure level to balance lung volumes and venous return
- Ensuring endotracheal tube/tracheostomy and ventilator circuit continuity to prevent unplanned airway dislodgement or tubing disconnections, as outlined in the 2022 guidance 1.
- The priority is to restore normal cardiac rhythm while maintaining patient safety and minimizing the risk of aerosolization, and the brief interruption in ventilation that may occur during defibrillation is generally well-tolerated. After defibrillation, promptly verify proper functioning of the ventilator, including checking that ventilation parameters return to appropriate settings and that the patient is being adequately ventilated.
From the Research
Ventilator Disconnection Prior to Defibrillation
- There is no direct evidence in the provided studies to suggest that a ventilator should be disconnected prior to defibrillation (cardioversion) 2, 3, 4, 5, 6.
- The studies focus on the methods of ventilation, such as passive oxygen insufflation, bag-valve-mask ventilation, and mechanical ventilation, and their effects on outcomes after out-of-hospital cardiac arrest or during cardiopulmonary resuscitation 2, 5, 6.
- One study discusses the importance of proper precautions during cardioversion and defibrillation, including the prevention of complications, but does not mention ventilator disconnection 4.
- Another study compares the rate of successful defibrillation using 1- and 2-min defibrillation intervals, but does not address ventilator disconnection 3.
Ventilation Methods and Outcomes
- The studies suggest that the method of ventilation can affect outcomes after out-of-hospital cardiac arrest or during cardiopulmonary resuscitation 2, 5, 6.
- For example, one study found that passive oxygen insufflation was associated with higher adjusted neurologically intact survival than bag-valve-mask ventilation in witnessed ventricular fibrillation/ventricular tachycardia out-of-hospital cardiac arrest 2.
- Another study found that lung inflation in ≥50% of pauses during 30:2 CPR was associated with improved return of spontaneous circulation, survival, and survival with favorable neurological outcome 5.
- However, the studies do not provide direct evidence on the necessity of disconnecting a ventilator prior to defibrillation (cardioversion) 2, 3, 4, 5, 6.