The nurse teaches the huffing technique to a client who has difficulty coughing. Which instruction is correct?

1. 1Take a medium breath, then push air out fast with a "ha" sound, mouth slightly open.
2. 2Inhale as deeply as possible and hold the breath for ten seconds before coughing.
3. 3Exhale slowly through pursed lips until the lungs feel completely empty of air.
4. 4Cough forcefully with the mouth tightly closed to build pressure in the chest.

Source: Nursing Fundamentals, 2nd edition (Open RN, Chippewa Valley Technical College, 2024), Oxygenation: HUFFING TECHNIQUE. Licensed under CC BY 4.0.