Assessment of lung function in patients with COPD using the Inspired Sinewave Technique

Bruce, Richard M.; Phan, Phi Anh; Rahman, Najib M.; Farmery, Andrew D.; Pacpaco, E.

doi:10.1183/1393003.congress-2017.pa2479

Cited by 1 publication

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our research in animals, in which we were able to standardise and control the degree of lung injury more reliably, proved more insightful. Bruce et al showed that ventilation heterogeneity could be determined by using the IST values in combination with the plethysmography results [8]. However, in this study, for the rst time, we used only the IST results to measure the heterogeneity of the lung without the need for plethysmography.…”

Section: Discussionmentioning

confidence: 99%

“…In the IST analysis, the deadspace volume inside the lung, V D IST , was rstly measured using the modied Bohr method [13]. Secondly, ELV and Q p were calculated from a model assuming one well-mixed lung compartment [8].…”

Section: Accepted Manuscriptmentioning

confidence: 99%

“…The IST applies a forced oscillation of a low dose of N 2 O tracer gas with a sinusoidal period which can be determined by the user. IST result provides lung function parameters, including deadspace volume (V D), eective lung volume (ELV ) and pulmonary blood ow (Qp) [6,7,8,9,10]. The IST results, including deadspace volume and eective lung volume provide suggestions to optimise the ventilator setting.…”

mentioning

confidence: 99%

“…Furthermore, it is proposed that by using two tracer gas frequencies, IST can quantify the ventilatory heterogeneity of the lung. In the previous study, the IST, used in combination with data from another lung function test (plethysmography), can detect changes in ventilatory heterogeneity which occur normally with age in healthy participants [8]. In another research in simulated patients, IST showed a potential to A c c e p t e d M a n u s c r i p t identify simulated patients had emphysema (ventilation heterogeneity) and pulmonary embolism (perfusion heterogeneity) [11].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Lung heterogeneity and deadspace volume in animals with acute respiratory distress syndrome using the inspired sinewave test

et al. 2020

View full text Add to dashboard Cite

Acute respiratory distress syndrome (ARDS) is associated with a high rate of morbidity and mortality, as patients undergoing mechanical ventilation are at risk of ventilator-induced lung injuries. Objective: To measure the lung heterogeneity and deadspace volume to find safer ventilator strategies. The ventilator settings could then offer homogeneous ventilation and theoretically equalize and reduce tidal strain/stress in the lung parenchyma. Approach: The inspired sinewave test (IST) is a non-invasive lung measurement tool which does not require cooperation from the patient. The IST can measure the effective lung volume, pulmonary blood flow and deadspace volume. We developed a computational simulation of the cardiopulmonary system to allow lung heterogeneity to be quantified using data solely derived from the IST. Then, the method to quantify lung heterogeneity using two IST tracer gas frequencies (180 and 60 s) was introduced and used in lung simulations and animal models. Thirteen anaesthetized pigs were studied with the IST both before and after experimental lung injury (saline-lavage ARDS model). The deadspace volume was compared between the IST and the SF6 washout method. Main results: The IST could measure lung heterogeneity using two tracer gas frequencies. Furthermore, the value of IST ventilation heterogeneity in ARDS lungs was higher than in control lungs at a positive end-expiratory pressure of 10 cmH2O (area under the curve = 0.85, p < 0.001 ). Values for the deadspace volume measured by the IST have a strong relationship with the measured values of SF6 (9 ml bias and limits of agreement from −79 to 57 ml in control animals). Significance: The IST technique has the potential for use in the identification of ventilation and perfusion heterogeneity during ventilator support.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Accepted Manuscriptmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations