<unk>  is indicated for any person unresponsive with no breathing or breathing only in occasional agonal gasps, as it is most likely that they are in cardiac arrest. If a person still has a pulse but is not breathing (respiratory arrest) artificial ventilations may be more appropriate, but, due to the difficulty people have in accurately assessing the presence or absence of a pulse,<unk>  guidelines recommend that lay persons should not be instructed to check the pulse, while giving healthcare professionals the option to check a pulse. In those with cardiac arrest due to trauma,<unk>  is considered futile but still recommended. Correcting the underlying cause such as a tension pneumothorax or pericardial tamponade may help.
Cardiopulmonary resuscitation
Extracorporeal cardiopulmonary resuscitation
Cardiopulmonary bypass
Extracorporeal membrane oxygenation
Rapid sequence induction
Mouth-to-mouth resuscitation
Resuscitation
Resuscitative thoracotomy