DCP And Flexivent: Complementary System Analysis For Longitudinal Disease Study
Longitudinal studies with the SCIREQ flexiVent require a high degree of user skill and may be challenging in tiny, highly diseased or extremely fragile subjects. The use of plethysmography equipment can allow data collection from conscious subjects to achieve physiologically descriptive parameters, and to characterize breathing patterns. These parameters are also highly complementary to later flexiVent, genetic and histological tests.
The Double Chamber Plethysmography system (DCP), restrains animals using two chambers to separate nasal and thoracic flows. When compared with whole body plethysmography, DCP offers additional parameters such as specific airway resistance (sRaw) and conductance (sGaw), as well at a true value of tidal volume rather than an estimated tidal volume.
In their recent studies1,2, Mailhot-Larouche et al. compare sRaw from both control and asthmatic mice which are taken from 3 days of data collection to values of both Newtonian and total respiratory system resistance parameters (Rn and Rrs respectively) from the flexiVent FX on the final day of the study. Good correlation is found between sRaw and Rrs (0.72), as well as between sRaw and Rn (0.72 to 0.81). The mice’s responses to the aerosol also follow similar trends across both platforms. The study authours conclude that DCP is a viable option for measuring mouse respiratory reactivity to aerosols. Data collection with DCP additionally offers easy collection of longitudinal measurements and lower user skill requirements.
Additional studies to compare sRaw to parameters that are gathered using the flexiVent’s Negative Pressure Forced Expiration (NPFE) extension are an interesting possibility and allows for comparison to similar publications in humans that compare sRaw and FEV values2.
Learn how complementing plethysmograph studies with the flexiVent detailed respiratory mechanics provides a more complete and powerful model analysis on functional and structural changes within a phenotype here
1Mailhot-Larouche; Beucher; Deschênes; Lortie,; Bossé,. (2017). Le pléthysmographe à deux chambres: Une étude comparative avec le FlexiVent chez des modèles murins sensibilisés à un allergène. Poster.
2 Mailhot-Larouche, Deschênes, Lortie, Gazzola, Marsolais, Brunet, Robichaud, Bossé. (2018). Assessment of Respiratory Function in Conscious Mice by Double-chamber Plethysmography. Vis. Exp. (137), e57778, doi:10.3791/57778
3 Mahut; Trinquart,; Bokov; Le Bourgeois; Waernessyckle,; Peiffer,; Delclaux. (2009). Relationships between Specific Airway Resistanceccv and Forced Expiratory Flows in Asthmatic Children. PLoS ONE; 4(4); e5270. DOI: 10.1371/journal.pone.0005270