Respiratory Inductance Plethysmography Improved Diagnostic Sensitivity and Specificity of Obstructive Sleep Apnea

Abstract

BACKGROUND: Respiratory inductance plethysmography (RIP) is a tool used during a polysomnogram (PSG), which serves as a surrogate of respiratory effort and can help detect inspiratory air-flow limitation. We hypothesize that RIP can improve the sensitivity and specificity of scoring hypopneas when compared with both the recommended and acceptable criteria of the American Academy of Sleep Medicine. METHODS: We retrospectively analyzed a cohort of 12 subjects who had no obstructive sleep apnea (OSA) or mild OSA on PSG when scored by the American Academy of Sleep Medicine acceptable criteria for hypopneas but had high clinical suspicion for a diagnosis of OSA. These subjects were rescored using the American Academy of Sleep Medicine recommended criteria as well as RIP. Hypopnea was scored when there was a 50% decrease in the amplitude of the RIP sum channel (which combined input from chest and abdominal belts). OSA was diagnosed if the subjects had >5 respiratory events/h of sleep. The subject's response to CPAP was assessed by using a short questionnaire called the post-PSG sleep assessment. which evaluated subjective sleep quality. A positive response was considered an improvement in the post-PSG sleep assessment score after CPAP use. RESULTS: When scored using the American Academy of Sleep Medicine acceptable criteria, 10 subjects had a negative study, and 2 subjects had mild OSA for a sensitivity of 11% and specificity of 50%. When scored using the recommended criteria, 10 subjects had OSA, and 2 were negative, for a sensitivity of 78% and specificity of 70%. By RIP scoring, all 12 subjects had >5 respiratory events/h for a sensitivity of 100% and specificity of 75%. CONCLUSIONS: This small retrospective pilot study showed improved sensitivity and specificity when scoring hypopneas by RIP sum channel.

Characterisation and Quantification of Upper Body Surface Motions for Tidal Volume Determination in Lung-Healthy Individuals

“…Putting the attention on circumferential changes, which are basically as well a distance change or expansion, then, due to the dynamic character and circular arrangement and the large dimension of these changes (changes up to 100 mm and more), their determination requires a special measuring principle. These dynamic circumferential changes of the upper body can be determined inductively, for example in RIP [ 35 ], by textile strain gauges [ 36 ], or by optical encoders via CiMeD belts [ 30 ].…”

Assessment of respiratory effort with EMG extracted from ECG recordings during prolonged breath holds: Insights into obstructive apnea and extreme physiology

“…Severe OSA is defined by ≥30 apneic or hypopneic events per hour (AASM, 1999) and individual events can range from 10 seconds (the minimum duration to be counted) to over 60 seconds (Leppanen et al, 2016). The struggle phase in volitional apnea and obstructive apnea is generally defined with inductance plethysmography (e.g., (Kogan et al, 2016)), however, this technique indirectly assesses respiratory effort. Berry and colleagues demonstrated chest wall electromyographic (EMG) signals associated with the electrocardiogram (ECG) were useful in defining periods of obstructive sleep apnea (Berry et al, ,,2016(Berry et al, ,, , 2018(Berry et al, ,, , 2019.…”

Clinical evaluation of stretchable and wearable inkjet-printed strain gauge sensor for respiratory rate monitoring at different measurements locations

“…It has been reported that the accuracy of RR measurements using strain gauge sensors changes with different body locations [18], [19]. However, the majority of existing studies on RR monitoring accuracy were focused at two common locations namely thorax [21]- [24] and abdomen [21], [23], [25]. Diagonal mounting of RR sensors [9], [20] was also investigated.…”