Approaches to Cough Peak Flow Measurement With Duchenne Muscular Dystrophy

Abstract

MI-E + assisted CPF was the highest. The CPF measured with the peak flow meter suggested underestimation.

A Review on Cough Augmentation Techniques: Assisted Inspiration, Assisted Expiration and Their Combination

“…Researchers and clinicians widely use the CPF values for assessing cough augmentation. Nonetheless, there is a known risk of fixed and proportional bias in assessing CPF with the peak flow meter, which is the outcome that most studies use and a measure that is easy to perform in the clinical setting (Kikuchi et al 2018, Kulnik et al 2019. Clinicians need to be cautious when they use the CPF cut off points to guide their clinical decision making for cough augmentation techniques (Kikuchi et al 2018, Kulnik et al 2019.…”

“…Nonetheless, there is a known risk of fixed and proportional bias in assessing CPF with the peak flow meter, which is the outcome that most studies use and a measure that is easy to perform in the clinical setting (Kikuchi et al 2018, Kulnik et al 2019. Clinicians need to be cautious when they use the CPF cut off points to guide their clinical decision making for cough augmentation techniques (Kikuchi et al 2018, Kulnik et al 2019. They need to assess the evidence about effectiveness, adverse effects, precautions and contraindications of the techniques, alongside patient assessment and ability to perform unsupported coughs.…”

“…The mean ± SD CPF during MAC with MI-E was 202.4±46.6 l/min compared to the unassisted cough, hyperinflation with MAC, and MI-E, 95.7±40.5, 155.9±53.1, 177.2±33.9, respectively (Kim et al 2016). A study with 12 patients with Duchenne muscular dystrophy found that MI-E with MAC generated higher CPF (240±38 l/min) compared to MAC (113±32 l/min) or MI-E (199±40 l/min) alone, hyperinflation with MAC (224±62 l/min), hyperinflation without MAC (170±30 l/min), and unassisted cough (59±34 l/min), all higher than unassisted cough, p<0.01 (Kikuchi, Satake et al 2018). Still, patients who reached CPF of 300 l/m using hyperinflation and MI-E did not have a higher CPF by adding MAC, probably because the cough effort from the combination of two exceeds the capacity of the device for pressure (Lacombe et al 2014, Kim, Choi et al 2016.…”

Accuracy in the Assessment of Cough Peak Flow: Good Progress for a “Work in Progress”

“…The authors reported differences in measurements between a spirometer and a mechanical insufflation-exsufflation device and between a peak flow meter and a spirometer, with Bland-Altman limits of agreement spanning 50 L/min. 10 These studies and the ERS statement highlight an important current limitation in the measurement of CPF, which is that different measurement devices perform variably, leading to potentially substantial inaccuracy in CPF measurements. Researchers and clinicians need to be aware of this, particularly when using absolute values of CPF as thresholds to guide clinical decisions.…”

Clinical Significance of Cough Peak Flow and Its Non-Contact Measurement via Cough Sounds: A Narrative Review

“…Various spirometers [3,[23][24][25][26] and peak flow meters [24,[26][27][28][29][30] are used for CPF measurement. Moreover, various flow sensors, such as a pneumotachograph [21,[23][24][25]31] that measures respiratory flow using differential pressure sensors, a constant temperature hot-wire flow sensor ( Figure 2a) [26,32] and an ultrasonic sensor [33], are used in spirometers. In particular, the peak flow meter that can measure the flow rate using a spring-loaded piston is most commonly used because of its small size and ease of use, enabling patients to measure CPF by themselves ( Figure 2b).…”