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Usefulness of a 4-Grade Novel Mouthpiece Device for Increased Mouth Pressure Reproducing Artificial Difficulty in
Akiko Yorita1, Yoshihisa Tokunaga1, Takashi Kinoshita1
1Division of Respirology, Neurology, and Rheumatology, Department of Medicine, Kurume University School of Medicine.
Objective:
The use of a novel 4-grade mouthpiece device to reproduce difficulty in breathing was assessed in healthy individuals.
Methods:
A double-blind, randomized, crossover-controlled trial was conducted to investigate the efficacy and safety of the device with increasing mouth pressure. The modified Borg (mBorg) scale values, respiratory system resistance at 5 Hz (R5), and forced expiratory volume in one second (FEV1) were assessed while using the device.
Materials:
The four grades of breathing difficulty device were tested in 32 healthy participants.
Results:
The 4-grade device linearly worsened the mBorg scale with increasing mouth pressure. The mean R5 (± standard deviation [SD]) with grade I, II, III, and IV devices were 5.6 ± 0.1, 10.3 ± 0.3, 21.5 ± 0.7, and 54.8 ± 2.0 kPa/L/s, respectively. The mean %FEV1 predicted (± SD) were 83.6 ± 15.9% with grade I, 55.3 ± 11.8% with grade II, 32.0 ± 6.1% with grade III, and 15.3 ± 3.2% with the grade IV device. The mBorg scale was positively correlated with R5 (r = 0.79, p < 0.0001) and negatively with %FEV1 predicted (r = -0.81, p < 0.0001). No severe adverse events were reported during the trial.
Conclusion:
We demonstrated that the novel device could effectively reproduce the semi-quantitative artificial difficulty in breathing safely and easily in healthy individuals. These devices could be helpful to understand the mechanisms of difficulty in breathing.
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