Bowel sounds

When auscultating for bowel sounds, one should use the bell of the stethoscope and listen for at least 30 seconds in several different places. Aside from normal noises, there are three situations which may be detected:

• absent bowel sounds:
  • over a three-minute period indicates paralytic ileus
    
    
• obstructed bowel produces a louder and more high pitched sound with a tinkling quality due to the presence of liquid and air
  
  
• intestinal hurry - occurs in diarrhoeal states - causes loud gurgling sounds often audible without a stethoscope

Stating that bowel sounds are increased or decreased is of little diagnostic value because the estimation of their loudness is subjective and varies with food transit.