Correlation between the changes respiratory resistance and reactance assessments, measured by forced oscillation technique (MostGraph), and respiratory-function assessments in childhood asthma

A noninvasive forced oscillation technique was used to determine respiratory function in unanesthetized and spontaneously breathing mice. Pseudorandom noise pressure variations in a frequency range of 16–208 Hz were applied to the body surface, and the flow response was measured at the nose. From the pressure-flow relationship, respiratory transfer impedance was calculated. Study of intra-animal variability on a short- and a long-term basis revealed that the real part of respiratory transfer impedance was reproducible within 9%. The imaginary part appeared less reproducible (within 22%). Furthermore, bronchoconstrictive responses were investigated and analyzed by evaluation of respiratory resistance as measured at 16 Hz (Rrs16). During the first 15 min after ovalbumin challenge in ovalbumin-sensitized mice, Rrs16 was significantly increased [49 +/- 7% (SE)]. Inhalation of methacholine in untreated mice induced an increase in Rrs16 of 75 +/- 16% (SE). In saline-challenged animals, no significant changes were observed. This method enables evaluation of long-term respiratory function in mice and appeared to be a sensitive measure for bronchoconstriction.

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Effect of age, height, and prechallenge respiratory resistance on bronchial hyperresponsiveness in childhood asthma using the forced oscillation technique

Pediatric Pulmonology ◽

10.1002/(sici)1099-0496(199607)22:1<1::aid-ppul1>3.0.co;2-v ◽

1996 ◽

Vol 22 (1) ◽

pp. 1-6 ◽

Cited By ~ 12

Author(s):

Hiroyuki Mochizuki ◽

Toshio Shimizu ◽

Makoto Shigeta ◽

Hirokazu Arakawa ◽

Kenichi Tokuyama ◽

...

Keyword(s):

Childhood Asthma ◽

Forced Oscillation ◽

Bronchial Hyperresponsiveness ◽

Forced Oscillation Technique ◽

Respiratory Resistance ◽

Effect Of Age

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Laryngeal resistance immediately after panting in control and constricted airways

Journal of Applied Physiology ◽

10.1152/jappl.1985.58.4.1164 ◽

1985 ◽

Vol 58 (4) ◽

pp. 1164-1169 ◽

Cited By ~ 4

Author(s):

K. Sekizawa ◽

H. Sasaki ◽

T. Takishima

Keyword(s):

Forced Oscillation ◽

Low Frequency ◽

Normal Subjects ◽

Forced Oscillation Technique ◽

Respiratory Resistance ◽

Frequency Sound ◽

Laryngeal Resistance ◽

Control State

Laryngeal resistance (Rla) in the postpanting interval (PPRla) was examined in five normal subjects in the control state and with methacholine- and histamine-induced bronchoconstriction. Respiratory resistance (Rrs) was measured by the forced oscillation technique at 10 Hz, and Rla was measured by the low-frequency sound method (Sekizawa, K., C. Shindoh, W. Hida, S. Suzuki, et al. J. Appl. Physiol. 55:591–597, 1983). Inspiratory Rrs (IRrs) was lower than expiratory Rrs (ERrs), and Rrs immediately after panting (PPRrs) was not significantly different from IRrs in the three airway conditions. Rla increased with bronchoconstriction and inspiratory Rla (IRla) was lower than expiratory Rla (ERla). PPRla was lower than IRla (P less than 0.01) by an amount corresponding to the decrease in Rrs in the control airway. However, in constricted airways, PPRla was higher than IRla and about the same as ERla. We suggest that the panting maneuver is suitable for minimizing the effect of laryngeal artifact in the control airway, but in the constricted airway the panting maneuver may fail to cause widening of the laryngeal orifice.

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Impact of lung disease on respiratory impedance in young children with cystic fibrosis

European Respiratory Journal ◽

10.1183/13993003.00156-2015 ◽

2015 ◽

Vol 46 (6) ◽

pp. 1672-1679 ◽

Cited By ~ 12

Author(s):

Kathryn A. Ramsey ◽

Sarath C. Ranganathan ◽

Catherine L. Gangell ◽

Lidija Turkovic ◽

Judy Park ◽

...

Keyword(s):

Cystic Fibrosis ◽

Preschool Children ◽

Lung Disease ◽

Forced Oscillation ◽

Forced Oscillation Technique ◽

Respiratory Resistance ◽

Lung Abnormalities ◽

Respiratory Inflammation ◽

Function Testing ◽

Tomography Scan

This study aimed to evaluate the ability of the forced oscillation technique (FOT) to detect underlying lung disease in preschool children with cystic fibrosis (CF) diagnosed following newborn screening.184 children (aged 3–6 years) with CF underwent lung function testing on 422 occasions using the FOT to assess respiratory resistance and reactance at the time of their annual bronchoalveolar lavage collection and chest computed tomography scan. We examined associations between FOT outcomes and the presence and progression of respiratory inflammation, infection and structural lung disease.Children with CF who had pronounced respiratory disease, including free neutrophil elastase activity, infection with pro-inflammatory pathogens and structural lung abnormalities had similar FOT outcomes to those children without detectable lung disease. In addition, the progression of lung disease over 1 year was not associated with worsening FOT outcomes.We conclude that the forced oscillation technique is relatively insensitive to detect underlying lung disease in preschool children with CF. However, FOT may still be of value in improving our understanding of the physiological changes associated with early CF lung disease.

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The Reliability of Respiratory Resistance Measured by the Forced Oscillation Technique

Clinical Science ◽

10.1042/cs071008pb ◽

1986 ◽

Vol 71 (s15) ◽

pp. 8P-9P

Author(s):

J.E. Neild ◽

C.H.C. Twort ◽

S. Chinn ◽

S. McCormack ◽

P.G.J. Burney ◽

...

Keyword(s):

Forced Oscillation ◽

Forced Oscillation Technique ◽

Respiratory Resistance

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Forced Oscillation Technique and Childhood Asthma

Allergology International ◽

10.2332/allergolint.12-rai-0440 ◽

2012 ◽

Vol 61 (3) ◽

pp. 373-383 ◽

Cited By ~ 20

Author(s):

Hiroyuki Mochizuki ◽

Kota Hirai ◽

Hideyuki Tabata

Keyword(s):

Childhood Asthma ◽

Forced Oscillation ◽

Forced Oscillation Technique

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Respiratory resistance by end-inspiratory occlusion and forced oscillations in intubated patients

Journal of Applied Physiology ◽

10.1152/jappl.1996.80.4.1105 ◽

1996 ◽

Vol 80 (4) ◽

pp. 1105-1111 ◽

Cited By ~ 12

Author(s):

L. Beydon ◽

P. Malassine ◽

A. M. Lorino ◽

C. Mariette ◽

F. Bonnet ◽

...

Keyword(s):

Forced Oscillation ◽

Forced Oscillations ◽

Forced Oscillation Technique ◽

Respiratory Impedance ◽

Respiratory Resistance ◽

Airway Occlusion ◽

Residual Capacity ◽

Occlusion Technique ◽

Air Compression ◽

Good Agreement

Measurement of respiratory impedance by the forced oscillation technique (FOT) in intubated patients requires corrections for the flow-dependent resistance, inertance, and air compression inside the endotracheal tube (ETT). Recently, we published a method to correct respiratory impedance for the mechanical contribution of the ETT. To validate this correction, we compared the respiratory resistance obtained with this method (Rfo) to the intrinsic (Rmin) and total resistances (RT) measured by the airway-occlusion technique (OCT) in 16 intubated sedated paralyzed ventilated patients. The FOT was applied at functional residual capacity in the 4- to 32-Hz frequency range, whereas the OCT was performed at the end of a normal constant-flow inspiration. Rmin corrected with Rfo measured at 16 and 32 Hz [Rfo(16) = 1.10 x Rmin + 0.10 cmH2O.s.l-1, r = 0.96, P < 0.001; Rfo(32) = 0.93 x Rmin + 0.72 cmH2O.s.l-1, r = 0.97, P < 0.001]. RT corrected with Rfo at 4 Hz [Rfo(4) = 1.11 x RT - 1.48 cmH2O.s.l-1; = 0.92; P < 0.001]. We conclude that the FOT improved by correction for the behavior of the ETT is in good agreement with the OCT in intubated patients.

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A modified measurement of respiratory resistance by forced oscillation during normal breathing

Journal of Applied Physiology ◽

10.1152/jappl.1975.39.2.305 ◽

1975 ◽

Vol 39 (2) ◽

pp. 305-311 ◽

Cited By ~ 16

Author(s):

D. C. Stanescu ◽

R. Fesler ◽

C. Veriter ◽

A. Fans ◽

L. Brasseur

Keyword(s):

Flow Rate ◽

Respiratory System ◽

Obstructive Lung Disease ◽

Forced Oscillation ◽

Forced Oscillation Technique ◽

Good Reproducibility ◽

Respiratory Resistance ◽

Normal Breathing ◽

Respiratory Flow ◽

Mouth Pressure

We have modified the measurements of the resistance of the respiratory system, Rrs, by the forced oscillation technique and we have developed equipment to automatically compute Rrs. Flow rate and mouth pressure are treated by selective averaging filters that remove the interference of the subject's respiratory flow on the imposed oscillations. The filtered mean Rrs represents a weighted ensemble average computer over both inspiration and expiration. This method avoids aberrant Rrs values, decreases the variability, and yields an unbiased mean Rrs. Rrs may be measured during slow or rapid spontaneous breathing, in normals and in obstructive patients, over a range of 3–9 Hz. A good reproducibility of Rrs at several days' interval was demonstrated. Frequency dependence of Rrs was found in patients with obstructive lung disease but not in healthy nonsmokers.

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