according to American Academy of Sleep Medicine (AASM) there are two definitions for scoring hypopnea
1- hypopnea requires at least a 30% reduction in airflow for at least 10 seconds
2- hypopnea requires at least a 50% reduction in airflow for at least 10 seconds
R.13. What is meant by "BASELINE" in the new AASM scoring manual? We are using the alternative definition for hypopnea in non‐Medicare patients. Hypopnea is defined as > 50% drop in the nasal pressure signal compared to baseline associated with either a 3% desaturation or an arousal. I am meeting with our techs on a regular basis in an attempt to insure uniform scoring under the new criteria. I have attached a typical example. The labeled events are those scored by the technologist. There are other events present which are associated with arousals which the tech did not score because he did not believe that there was a 50% drop in flow. There is a 50% drop in flow compared to the recovery breaths but this may not be "baseline" in that the patient is hyperventilating in response to the event. Is it acceptable to use the amplitude of these three to four breaths following the event as "baseline" and compare the reduced breaths to these?
If there is no clear baseline breathing to measure, due to a high frequency of abnormal respiratory events, then the recovery breaths between the frequent apneas or hypopneas would be acceptable to use for an approximate baseline against which to measure the percent of drop for the next reduction in airflow.