title: Direct mechanical heart massage.
mesh_terms: D000136:Acid-Base Equilibrium; D000818:Animals; D001775:Blood Circulation; D001794:Blood Pressure; D004285:Dogs; D006336:Heart Massage / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood; D014586:USSR; D014655:Vascular Resistance; D014690:Venous Pressure
chemical_list: D010100:Oxygen