When the smoke filled the auditorium, he began to hyperventilate and struggled to stay calm.

Whenever the lights flicker unexpectedly, she hyperventilates and needs a moment to calm down.

She hyperventilated in the crowded elevator and had to sit down.

During the panic attack, she experienced several hyperventilations that left her dizzy and lightheaded.

During the demonstration, the technicians warned that the hyperventilators could trigger panic in susceptible patients.

When the tour bus hit turbulence, the hyperventilator in the back row began breathing rapidly and had to be calmed down.

After the sudden noise, he sat down, hyperventilating and clutching his chest.

During the panic attack, his hyperventilation caused him to feel dizzy and tingly.

The patient's hyperventilative episode alarmed everyone in the emergency room.