Manual vs. mechanical ventilation in patients with advanced airway during CPR.

Early chest compressions and rapid defibrillation are important components of cardiopulmonary resuscitation (CPR). American heart association (AHA) recommends two breaths to be delivered for every 30 compressions for an adult cardiac arrest victim. Patient with an advanced airway like endotracheal tube (ETT) should be given one breath every 6 s without interruptions in chest compression (10 breaths per minute). All of the modern mechanical ventilators have option to generate spontaneous breaths by the patient if the patient has spontaneous respiratory efforts. During CPR, the mechanical ventilator is fallaciously sensing the chest compressions as patient's spontaneous trigger and thereby it delivers higher respiratory rates. Avoiding excessive ventilation is one of the components of high quality CPR as excessive ventilation decreases venous return thereby decreasing the cardiac output and also it affects intra-thoracic pressure thereby adversely affects intra-arterial pressure. As modern ventilators have trigger for spontaneous breaths and they will be erroneously triggered by chest compressions, it would be prudent to use volume marked resuscitation bags or manual breathing devices (manual self-inflating resuscitation bag, Bain's circuit) for delivering breaths which can be synchronised with compression phase of CPR at RR of 10 breaths per min with advanced airway in place. If any patient who is on mechanical ventilation develops cardiac arrest, patient should be disconnected from the mechanical ventilator and should be ventilated manually. Manual ventilation with aforementioned breathing devices should be used in a patient without and with advanced airway devices during CPR.