Why does the doctor say thirty-three?

It contains consonants and vibrates strongly in the chest: at that point, the intensity of the sound allows for diagnosis. Why, instead, are the chest and abdomen tapped?

di |
Easter Eggs57

During a medical exam, the doctor may have you say "thirty-three" while placing his hand on your chest. In reality, this ancient and still very effective method simply uses the vibrations of your voice to understand how they propagate through your lungs and rib cage.

The number “thirty-three” is traditional because it contains voiced consonants and vibrates well in the chest.

So "saying thirty-three" is mainly useful for understanding:

  • if the lung transmits sound normally,
  • too good,
  • or too little.

As you say it, the doctor listens with the stethoscope to see if the sound comes through:

  • muffled: there may be air or liquid obstructing transmission;
  • muffled and indistinct: with attenuated vibrations, it means that the conditions are normal;
  • weak: there is excess air in the lungs, which could indicate a chronic obstructive pulmonary disease (COPD) or emphysema;
  • louder or clearer than normal: may indicate that the lung tissue has become “denser”, as can happen in the presence of inflammation or an infection (for example pneumonia);
  • asymmetrical between the two sides: may suggest a localized problem.

This test is part of the evaluation of the so-called vocal quiver and the transmission of voice into the lungs: a rapid, painless, and very ancient procedure in clinical medicine, which is still considered today a valuable tool, a key clue, to make a diagnosis during the visit, and before any tests.

Another ancient and still very effective method for quickly reaching a diagnosis is chest and abdominal percussion. This involves "tapping" the body with the fingers to determine, from the sound produced, what is underneath: air, liquid, or solid tissue. This technique is widely used on both the chest and abdomen.

In Chest, percussion is mainly used to evaluate the lungs:

  • Clear/resonant sound → normal, indicates lung full of air.
  • Dull sound (duller) → may indicate pneumonia, pleural fluid, or a mass.
  • Hyper-resonant sound (too “empty”) → may appear in emphysema or pneumothorax.

In Chest so it helps to understand if there is:

  • too much air,
  • too little air,
  • liquid,
  • or thickened fabric.

In 'abdomen, instead, is used to understand the distribution of air, liquids and organs:

  • Tympanic sound (drum-like) → normal presence of air in the intestine.
  • Dull sound → may indicate enlarged organs, masses, stool or free fluid in the abdomen (ascites).

With abdominal percussion the doctor can orient himself on:

  • liver and spleen size,
  • accumulation of fluid,
  • intestinal distension,
  • presence of masses.

It is a simple but very useful method because it provides immediate information without invasive tools.

Read also:

Want to see a selection of our news?

Don't Waste