The eBay pages are full of recording Pulse Oximeters. I compared mine to a professional multi thousand dollar unit and the profiles mirrored each other. Downloading via a USB cable to a CD program could not be simpler. Naturally programs range from simple to stupidly complex but the basic nightly or weekly results can be amplified down to the minute. This is the way I found put the shoulder I was sleeping on started to hurt at 0400 I rolled over more supported myself with my right hand and woke up at 0500 screaming with pain. You bet your sweet bippy the O2 sensor showedbwhy my AHI was.skyrocketing. bolster pillows and an ice pack at bed time fixed that and my heart rate and pulse have also returned to normal. St Peter has all of eternity so seeing him right away is not a priority. If a person is being treated for Atrial Fibrillation a pulse oximeter should br mandatory. I dose one of my medications PRN via what my pulse history has shown.