Another approach is to change the way breaths are used to calm himself. Instead of counting the number of breaths, he may benefit from counting in the context oof individual breaths:

1. Inhale slowly through the nose over four counts, either continuously or rhythmically.
2. Hold four counts.
3. Exhale slowly through the mouth over four counts.

Repeat until calm or asleep!

...pronounced like the long vowel and first letter of the alphabet...