Category Archives: Respiratory

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Conclusion

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: ConclusionHowever, in the supine position with increased abdominal compliance, diaphragmatic contraction may cause more outward abdomen motion before the onset of outward RC motion and a weaker coupling of diaphragm contraction and RC expansion, leading to less synchronous thoracoabdominal motion. In addition, the increased RC compliance in the 3- to 5-year-old age group compared to adults would be expected to exaggerate this mechanism.
Our results stress the importance of controlling for testing position in any comparative study of thoracoabdominal motion under conditions of respiratory loading, of lung or chest wall disease, or for longitudinal measurement. The ease in performing RIP and the need for minimal patient cooperation may make it a useful adjunct to or replacement for other modes of respiratory function testing in preschool-age children. In order to show this, further studies will be necessary to assess the ability of RIP measurements to discriminate healthy patients from those with lung disease, and to provide accurate longitudinal measurements of lung function in children with and without lung disease. further

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Feasibility and Success

Although there are no published data on the feasibility and success of performing RIP measurements in 3- to 5-year-old children, there are such data published on spirometry. Eigen et al showed a success of 83% in naive 3- to 6-year-old children, but did not list the success relative to age. In 3- to 5-year-old children, Kanengiser and Dozor2 showed a feasibility of 90% and success (the ability to reproducibly produce FEV1 during a trial of spirometry) of 56% in performing spirometry. They also showed an improvement in success with age.2 The study by Crenese et al, however, showed a success of 49%, which did not change with age. The high feasibility (> 95%) and success (> 80%) in performing RIP measurements in 3- to 5-year-old children shows that RIP can be easily performed in this age group.

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Discussion

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: DiscussionThe mean ± SEM LBI measured in the sitting position was 1.01 ± 0.01. The LBI was not recorded in the supine and standing positions since volume calibration was not repeated after each change in position and the LBI requires a volume calibration.
When the subjects were in the supine position, many had an inward motion of the RC at the beginning of inspiration (Figs 2, 3). There was outward motion of both the thorax and abdomen at the onset of inspiration in both the sitting and standing positions (Fig 2).
Figures 4-6 show the mean (± 2 SEM) for Ф, PhRTB, and Tptef/Te in the sitting, supine, and standing positions. The SAS Proc Mixed procedure (SAS Institute) was used for comparing Ф, PhRTB, Tptef/Te, and Ti/Ttot by position. Table 5 shows the results of post hoc analyses. The statistical significance for pairwise comparison was adjusted to p < 0.017 using the Bonferroni method. There were significant differences in Ф and PhRTB between the sitting and supine positions, and supine and standing positions, and for PhRTB between the sitting and standing positions (Table 5). Tptef/Te and Ti/Ttot were significantly higher in the supine position compared to the sitting or standing positions (Table 5). fully

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Statistical Analysis

To evaluate the ease of use of RIP, we evaluated the feasibility and success of the procedure related to age. The feasibility was defined as the willingness of a child to perform the testing. The success was defined as the ability of a child to perform the procedure well, by the criteria described above.
Data were examined and described using mean, median, SD, and range. The associations between position (sitting, supine, and standing) and Ф, LBI, PhRTB, Tptef/Te, and Ti/Ttot were examined using the mixed-effects model with an unstructured covariance matrix to account for the correlation between the repeated measurements obtained at each position within each subject. Post hoc analysis was performed to further examine differences between the three positions. The statistical significance for pairwise comparison was adjusted to 0.017 using the Bonferroni method. We performed a Pearson or Spearman correlation to examine the relationship between age, weight, height, and gender and Ф, LBI, PhRTB, Tptef/Te, and Ti/Ttot in each position. The data were analyzed using SAS version 8 (SAS Institute; Cary, NC). www.cheap-asthma-inhalers.com

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Data Analysis

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Data AnalysisThe LBI is the ratio of the absolute value of the sum of the maximal excursions in the RC and abdomen (maximal compartment amplitude) to tidal volume. When breathing in perfect synchrony, and assuming two degrees of freedom in the respiratory system, the volume change in the thorax and abdomen should equal the tidal volume and the LBI is 1.0. As thoracoabdominal motion becomes more asynchronous, greater excursion in one compartment is needed to overcome the excursion in the opposite direction in the other compartment in order to maintain a given tidal volume. With this, the maximal compartment amplitude increases above the tidal volume and the LBI increases > 1.0. Since calculating LBI requires absolute measures of volume, volume-calibrated abdominal, RC, and tidal volume signals are needed.

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Respiratory System Mechanics Using RIP

The subjects remained in the sitting position while data recording was begun. Throughout the data recording, the investigator monitored the scalar tracing and Konno-Mead loop to ensure adequate signal quality, and continued reading a story to the subject. After approximately 3 to 5 min of data recording, the subjects were moved to the supine position and the investigator carefully held the RespiBands to prevent movement. The scalar tracing was then marked and data recording continued in an identical manner while the subjects were supine and then while standing, for 3 to 5 min each. The total study time per patient varied between 20 min and 25 min (Table 2).

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Experimental Protocol

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Experimental ProtocolEach band was fitted while the subject was in the sitting position and was stretched slightly around the subject to ensure a tight fit and to minimize the signal distortion with change in position. The bands were taped in place with silk medical tape, and their position was closely monitored throughout the study. During changes in position, an investigator held the cable connecting the inductance bands to the Respitrace unit (model 204; NonInvasive Monitoring Systems; Miami Beach, FL) and placed a hand over the inductance bands to ensure positional stability.
Inductance from each band was recorded on the Respitrace model 204. Relative calibration, using the quantitative diagnostic calibration (QDC) procedure, and volume calibration were performed using RespiPanel v1.4c software (NonInvasive Monitoring Systems). Inductance was converted to a relative measure of cross-sectional area using RespiEvents v5.2e (NonInvasive Monitoring Systems). The RC, abdominal, and summation signals were displayed in scalar fashion in real-time and recorded on a Dell Inspiron 5000 laptop computer (Dell Products; Round Rock, TX) with a 600-mHz processor. Additionally, an RC vs abdominal plot (a Konno-Mead or Lissajous plot) and a flow-volume loop were made for each breath using flow derived from volume. read more

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children: Materials and Methods

Understanding the variation in RIP measurements with position is critical in ensuring accurate interpretation of measurements of respiratory system function made with this technique. Vellody et al and Druz and Sharp showed change in thoracic and abdominal compliance between the sitting and supine positions. Verschakelen and Demedts showed that there was significant difference in thoracoabdominal motion between the sitting, standing, and supine positions during vital capacity maneuvers in teenagers and adults.
The primary objectives of this study were to demonstrate the ease of performing RIP measurements, to characterize the values for a variety of RIP measurements, and to assess their dependence on body position in normal 3- to 5-year-old children. We hypothesized that RIP measurements of respiratory system mechanics would change with position due to alteration in thoracoabdominal mechanics between the sitting, supine, and standing positions.

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old Children

Respiratory Inductance Plethysmography in Healthy 3- to 5-Year-Old ChildrenObjective assessment of respiratory system function is important during early childhood, when substantial growth of the lungs and airways occurs. In older children and adults, spirometry is used to assess pulmonary function. In infants, alternative measurements of lung function are used, such as measurement of dynamic compliance and the raised volume rapid thoracic compression technique. Both of these techniques require sedation. Respiratory function measurements in 3- to 5-year-old children are more difficult, however, because children this age are often too young to cooperate with spirometry and are challenging to sedate. Because of these limitations, there is a paucity of normal respiratory function data in children of this age group. Recently, the use of spirometry has been studied as a measurement of lung function in 3- to 6-year-old children, and success in performing spirometry in children this age has ranged between 49% and 83%. Link