Spirometry in healthy subjects: do technical details of the test procedure affect the results?

The effect of nose clip on exercise-induced bronchoconstriction in adolescents

BACKGROUND

Oral breathing is considered to increase hyper-responsiveness of the airways. Data on the need for nose clip (NC) during exercise challenge test (ECT) in children and adolescents is scarce. Ouraim was to evaluate the role of NC during ECT in children and adolescents.

METHODS

A prospective, cohort study; children referred for ECT were evaluated on two separate visits, with and without a NC. Demographic, clinical data and measurements of lung functions were recorded. Allergy and asthma control were evaluated by Total Nasal Symptoms Score (TNSS) and Asthma Control Test (ACT) questionnaires.

RESULTS

Sixty children and adolescents (mean age 16.7 ± 1.1 years, 38% Female,) performed ECT with NC and 48 (80%) completed visit 2 (ECT without NC), 8.7 ± 7.9 days after visit 1. Following exercise, 29/48 patients (60.4%) with NC had a decline of ≥12% in forced expiratory volume in the first second (FEV1 ) (positive ECT) compared to only 16/48 (33.3%) positive tests without NC (p = 0.0008). Test result was changed in 14 patients from positive ECT (with NC) to negative ECT (no NC) and in only one patient from negative to positive. The use of NC resulted in greater FEV1 decline (median 16.3% predicted, IQR 6.0-19.1% predicted vs. median 4.5% predicted, IQR 1.6-18.4% predicted, p = 0.0001), and better FEV1 increase after bronchodil at or inhalation compared to ECT without NC. Higher TNSS scores did not predict higher probability to positive ECT.

CONCLUSIONS

The use of NC during ECT increases detection rate of exercise induced bronchoconstriction during ECT in the pediatric population. These findings strengthen the recommendation of nasal blockage during ECT in children and adolescents.

Effects of Inspiratory Muscle Training on Clinical Predictors of Respiratory Muscle Strength and Lung Function in Burned Patients with Inhalation Injury

Chronic airway illness is a well-documented inhalation injury side effect. Many pulmonary function impairments persisted for several months after lung parenchymal injury. Thus, the purpose of this study was to investigate the effects of inspiratory muscle training on respiratory muscle strength and pulmonary function (PFT) in patients who had suffered an inhalation injury. This study included male patients with inhalation injuries aged 20-35 years. Patients were chosen at random and assigned to an exercise group, which received inspiratory muscle training and routine chest physiotherapy, including early ambulation, coughing, and deep breathing, three times weekly for 4 weeks, and the control group, which only received routine chest physiotherapy. All participants were assessed for PFT and respiratory muscle strength at enrollment and the end of the study. The statistical analysis for outcome variables between both groups revealed no significant differences before treatment (P > .05) of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), maximal inspiratory pressure, and maximal expiratory pressure. According to the findings of this study, including IMT as part of a physical therapy program led to significant gains (P ˂ .05) in FVC and FEV1. However, after treatment, there was not a substantial difference found in either the MIP or the MEP between the groups. The exercise group performed better in terms of FVC, FEV1, MIP, and MEP after receiving treatment, according to these significant and non-significant differences.

Morpho-functional evaluation of lung aeration as a marker of sickle-cell acute chest syndrome severity in the ICU: a prospective cohort study

Background

Acute chest syndrome (ACS) is the main cause of morbi-mortality in patients with sickle-cell disease in the intensive care unit (ICU). ACS definition encompasses many types of lung damage, making early detection of the most severe forms challenging. We aimed to describe ACS-related lung ultrasound (LU) patterns and determine LU performance to assess ACS outcome.

Results

We performed a prospective cohort study including 56 ICU patients hospitalized for ACS in a tertiary university hospital (Paris, France). LU and bedside spirometry were performed at admission (D0) and after 48 h (D2). Complicated outcome was defined by the need for transfusion of ≥ 3 red blood cell units, mechanical ventilation, ICU length-of-stay > 5 days, or death. A severe loss of lung aeration was observed in all patients, predominantly in inferior lobes, and was associated with decreased vital capacity (22 [15–33]% of predicted). The LU Score was 24 [20–28] on D0 and 20 [15–24] on D2. Twenty-five percent of patients (14/56) had a complicated outcome. Neither oxygen supply, pain score, haemoglobin, LDH and bilirubin values at D0; nor their change at D2, differed regarding patient outcome. Conversely, LU re-aeration score and spirometry change at D2 improved significantly more in patients with a favourable outcome. A negative LU re-aeration score at D2 was an independent marker of severity of ACS in ICU.

Conclusions

ACS is associated with severe loss of lung aeration, whose resolution is associated with favourable outcome. Serial bedside LU may accurately and early identify ACS patients at risk of complicated outcome.

Joint Indian Chest Society-National College of Chest Physicians (India) guidelines for spirometry

Although a simple and useful pulmonary function test, spirometry remains underutilized in India. The Indian Chest Society and National College of Chest Physicians (India) jointly supported an expert group to provide recommendations for spirometry in India. Based on a scientific grading of available published evidence, as well as other international recommendations, we propose a consensus statement for planning, performing and interpreting spirometry in a systematic manner across all levels of healthcare in India. We stress the use of standard equipment, and the need for quality control, to optimize testing. Important technical requirements for patient selection, and proper conduct of the vital capacity maneuver, are outlined. A brief algorithm to interpret and report spirometric data using minimal and most important variables is presented. The use of statistically valid lower limits of normality during interpretation is emphasized, and a listing of Indian reference equations is provided for this purpose. Other important issues such as peak expiratory flow, bronchodilator reversibility testing, and technician training are also discussed. We hope that this document will improve use of spirometry in a standardized fashion across diverse settings in India.