<prompt> What is the name of this test to be done before drawing an aerial blood gas sample:Virchow testWater hammer testAllen testTrendelenburg test  <response>: Allens test: to assess the aerial blood supply of the hand A - Both radial ulnar aery are occluded; B - Ulnar aery kept occluded, Radial aery released Water hammer test- to detect water hammer pulse in aoic regurgitation Trendelenburg test- to detect weakness of hip abductors 