The fist as an external cardiac pacemaker.
D000138:Acidosis / Q000517:prevention & control; D000368:Aged; D004562:Electrocardiography; D005260:Female; D005392:First Aid; D006323:Heart Arrest / Q000628:therapy*; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011674:Pulse; D012151:Resuscitation; D013909:Thorax