Apnea

What stops during an apnea?

Airflow is the air moving through the nose and mouth as we breathe. During an apnea, that flow becomes very small or stops for a period. The body may continue trying to breathe. That is why airflow and breathing effort are different pieces of information.

Clinical scoring rules consider both the size of the change in the signal and its duration. Adult criteria cannot simply be applied to children. Listening to a recording or timing a pause yourself does not provide the same measurements.

Sources: AASM: Rules for Scoring Respiratory Events in Sleep (2012 update)

Obstructive, central, and mixed events

During an obstructive apnea, the airway is blocked while the body continues trying to breathe. During a central apnea, breathing effort is absent because the signals controlling breathing temporarily fail to produce that effort. A mixed event has features of both. Recording several signals helps a clinician distinguish them.

Sources: NHLBI: What Is Sleep Apnea? · AASM: Rules for Scoring Respiratory Events in Sleep (2012 update)

How the word appears in a sleep report

A report may describe the number and types of apneas and when they occurred. These findings need to be interpreted alongside the quality of the recording and the rest of the evaluation. Apneas and hypopneas may be counted together in an index describing events per hour.

One word or number answers only part of the question. Ask what the study showed, which types of events were most common, and how the findings relate to your symptoms and medical history.

Sources: AASM diagnostic testing guideline, 2017, original paper

Describe what someone observed

For example, a partner might say that snoring became quiet and was followed by a strong gasp. This describes something they heard or saw. It does not establish whether airflow stopped or which type of breathing event occurred.

Use your own words when explaining an observation instead of trying to diagnose it. Repeated breathing pauses, gasping, and daytime sleepiness are useful information to discuss with your primary care provider or sleep specialist.

Sources: NHLBI: Symptoms

Questions about a report

• Does the report describe an individual event or a diagnosed sleep disorder?
• Was breathing effort present during the events?
• What do these findings mean alongside my symptoms and the other measurements?