A Cloth Facemask Causes No Major Respiratory or Cardiovascular Perturbations during Moderate to Heavy Exercise

Objectives: To investigate whether wearing a cloth facemask could affect physiological and perceptual responses to exercise at distinct exercise intensities in non-trained men and women. Methods: In a crossover design, participants (17 men and 18 women) underwent a progressive square-wave test at four intensities (i. at 80% of the ventilatory anerobic threshold [80%VAT]; ii. at VAT; iii. at the respiratory compensation point [RCP]; iv. at exercise peak [Peak] to exhaustion), with or without a triple-layered cloth mask (Mask or No-Mask). Several physiological, metabolic and perceptual measures were analyzed. Results: Mask reduced inspiratory capacity at all exercise intensities vs. No-Mask (p<0.0001), irrespective of sex. Mask reduced respiratory frequency vs. No-Mask (p=0.001) at Peak (-8.3 breaths/min; CI: -5.8, -10.8), RCP (-6.9 breaths/min; CI: -4.6, -9.2) and VAT (-6.5 breaths/min; CI: -4.1, -8.8), but not at Baseline or at 80%VAT. Mask also reduced tidal volume (p<0.0001) at both RCP (-0.5L; CI: -0.3, -0.6) and Peak (-0.8L; CI: -0.6, -0.9), but not at Baseline, 80%VAT or VAT. Shallow breathing index was increased with Mask at Peak compared to No-Mask (11.3; CI: 7.5, 15.1), but not at any other intensities. Mask did not change heart rate, lactate, ratings of perceived exertion, blood pressure or oxygen saturation. Conclusions: Wearing a cloth facemask during exercise at moderate to heavy intensities is unlikely to incur significant respiratory or cardiovascular changes, irrespective of sex. These data can inform new exercise recommendations for health during the COVID-19 pandemic and debunk unfounded allegations of harmful effects of masks during exercise. ClinicalTrials.gov: NCT04887714

Effect of Six-Minute Walk Test and Incremental Exercise on Inspiratory Capacity, Ventilatory Constraints, Breathlessness and Exercise Performance in Sedentary Male Smokers without Airway Obstruction

We investigated physiological responses and exercise capacity in sedentary young smokers during sub-maximal and maximal test and its impact on dyspnea and exercise intolerance. Fifty sedentary male smokers and non-smokers (age: 24 ± 1 years., weight: 71 ± 9 kg, height: 177.3 ± 4.8 cm, body mass index: 22.6 ± 2.5 kg/m2) underwent two visits with pulmonary function tests, breathing pattern, and inspiratory capacity measurement at rest and during sub-maximal and maximal exercise. Smokers show reduced exercise capacity during six minutes walk test (6-MWT) with decreased walked distance (p < 0.001) and inspiratory capacity (p < 0.05). During cardiopulmonary exercise test (CPET), smokers had higher minute ventilation VE for a given submaximal intensity (p < 0.05) and lower minute ventilation at maximal exercise (p < 0.001). End expiratory lung volume was significantly lower in sedentary smokers at rest (p < 0.05), at ventilatory threshold during exercise (p < 0.05), but not during peak exercise. End inspiratory lung volume was significantly lower in smokers at rest (p < 0.05) and ventilatory threshold (p < 0.05). Cigarette smoking alters lung function during submaximal and maximal exercise. This alteration is manifested by the development of dynamic hyperinflation contributing to exercise capacity limitation.

Portable High-Flow Nasal Oxygen during Walking in Patients with Severe Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial

<b><i>Background:</i></b> High-flow nasal oxygen (HFNO) improves exercise capacity, oxygen saturation, and symptoms in patients with chronic obstructive pulmonary disease (COPD). Due to the need of electricity supply, HFNO has not been applied during free ambulation. <b><i>Objective:</i></b> We evaluated whether HFNO delivered during walking by a battery-supplied portable device was more effective than usual portable oxygen in improving exercise capacity in patients with COPD and severe exercise limitation. The effects on 6-min walking tests (6MWTs) were the primary outcome. <b><i>Methods:</i></b> After a baseline 6MWT, 20 stable patients requiring an oxygen inspiratory fraction (FiO₂) &#x3c;0.60 during exercise, randomly underwent 2 6MWT carrying a rollator, under either HFNO with a portable device (HFNO test) or oxygen supplementation by a Venturi mask (Control) at isoFiO₂. Walked distance, perceived dyspnea, pulse oximetry, and inspiratory capacity at end of the tests as well as patients’ comfort were compared between the tests. <b><i>Results:</i></b> As compared to baseline, walked distance improved significantly more in HFNO than in the control test (by 61.1 ± 37.8 and 39.7 ± 43.8 m, respectively, <i>p</i> = 0.01). There were no significant differences between the tests in dyspnea, peripheral oxygen saturation, or inspiratory capacity, but HFNO test was appreciated as more comfortable. <b><i>Conclusion:</i></b> In patients with COPD and severe exercise limitation, HFNO delivered by a battery-supplied portable device was more effective in improving walking distance than usual oxygen supplementation.

Effect of post-operative physiotherapy intervention following decortication and bullectomy: a case report

Decortication surgery is indicated in case of thickened pleural layer leading to atelectasis of the underlying lung parenchyma. It is done to prevent further restriction of the lung parenchyma. Atelectasis and collapse of lung following decortication is a common complication following the surgery. Chest physiotherapy following decortication helps in preventing the damage to the lungs and also helps in maintaining and regaining good lung function post-surgery. We present a case of right lung decortication surgery with bullectomy where various physiotherapy intervention and techniques were started early post-surgery to attain good lung expansion and prevent complications. Physiotherapy interventions like segmental breathing exercises, chest proprioceptive neuromuscular facilitation techniques, lung expansion exercises, unilateral expansion exercises, use of incentive spirometer, airway clearance techniques, resistance training and early mobilisation showed significant improvement in the chest excursion and expansion along with improved inspiratory capacity. Along with this it also helps in reducing the length of ICU (Intensive care unit) stay. Physiotherapy along with early mobilisation when started in the early postoperative period following decortications and bullectomy surgeries is useful to obtain better outcomes and shorten length of ICU stay.

The Effect of Long-Acting Dual Bronchodilator Therapy on Exercise Tolerance, Dynamic Hyperinflation and Dead Space during Constant Work Rate Exercise in COPD

Purpose: We investigated whether dual bronchodilator therapy (glycopyrrolate/formoterol fumarate; GFF; Bevespi Aerosphere®) would increase exercise tolerance during a high-intensity constant work rate exercise test (CWRET) and the relative contributions of dead space ventilation (VD/VT) and dynamic hyperinflation (change in inspiratory capacity) to exercise limitation in COPD. Methods: 48 COPD patients (62.9±7.6yrs; 33 male; GOLD spirometry stage 1/2/3/4, n=2/35/11/0) performed a randomized, double blind, placebo (PL) controlled, two period crossover, single-center trial. Gas exchange and inspiratory capacity (IC) were assessed during cycle ergometry at 80% incremental exercise peak work rate. Transcutaneous PCO2(TcPCO2) measurement was used for VD/VTestimation. Results: Baseline post-albuterol FEV1was 1.86±0.58L (63.6%±13.9 predicted). GFF increased FEV1by 0.18±0.21L relative to PL (P<0.001). CWRET endurance time was greater after GFF vs. PL (383±184s vs 328±115s; difference 55±125s; P=0.013; C.I. 20-90s), a 17% increase. IC on GFF was above placebo IC at all time points and fell less with GFF vs. PL (P≤0.0001). Isotime tidal volume (1.54±0.50 vs. 1.47±0.45L; P=0.022) and ventilation (52.9±19.9 vs. 51.0±18.9 L/min; P=0.011) were greater, and respiratory rate was unchanged (34.9±9.2 vs. 35.1±8.0 br/min, P=0.865). Isotime VD/VTdid not differ between groups (GFF 0.28±0.08 vs. PL 0.27±0.09; P=0.926). Conclusions: GFF increased exercise tolerance in COPD patients and the increase was accompanied by attenuated dynamic hyperinflation without altering VD/VT. ClinicalTrials.Gov Identifier: NCT03081156

RESPIRATORY FUNCTION IN NORMAL SINGLETON PREGNANCY, MULTIFETAL GESTATION AND POLYHYDRAMNIOS

Background : Study of respiratory functions of four groups of women: Nonpregnant, early pregnancy, singleton pregnancy at 36 weeks and twin/polyhydramnios at 36 weeks reveal that inspiratory capacity (IC), tidal volume (TV) and expiratory reserve volume (ERV) in different group pairing have statistically signicant difference. This is very important during the assessment of pregnant mother suffering from respiratory or cardiopulmonary disorder. Objectives :This study aims to observe the additional demands placed on the maternal respiratory system in cases of advanced normal pregnancy or over distended uterus, like multifetal gestation and polyhydramnios, and whether the average Indian woman is able to cope with these respiratory changes. Methods : Around 80 women were divided into four equal groups which included non-pregnant controls, normal early pregnancy (< 20 weeks), normal singleton pregnancy at 36 weeks and multifetal gestation/polyhydramnios, underwent spirometry for static lung volume measurement. The overall comparison was done by using the Kruskal-Wallis test whereas the individual comparison by Mann-Whitney test. Final statistical computing was performed with SPSS statistical package. Results : The groups were comparable on the basis of age, height and hemoglobin levels. Comparisons of various groups show statistically signicant difference in tidal volume, inspiratory capacity and expiratory reserve volume specially in advance pregnancy with control nonpregnant mothers without signicant adverse effect on respiratory system. Conclusions : Results of the study indicate that though there are signicant respiratory functional changes, healthy women, even having twin/polyhydramnios, can tolerate this well. But this knowledge is very important to assess and to formulate management of pregnant women with respiratory or cardiopulmonary compromise.

Intratracheal budesonide/surfactant attenuates hyperoxia-induced lung injury in preterm rabbits

Recent clinical trials have shown improvements in neonatal outcomes after intratracheal administration of a combination of budesonide/surfactant (ITBS) in infants at risk of bronchopulmonary dysplasia. However, the effect of ITBS on lung function and alveolar structure is not known. We aimed to determine the effect of ITBS on lung function, parenchymal structure, and inflammatory cytokine expression in a relevant preterm animal model for bronchopulmonary dysplasia. Premature neonatal rabbits were administered a single dose of ITBS on the day of delivery and exposed to 95% oxygen. Following 7 days of hyperoxia, in vivo forced oscillation and pressure-volume maneuvers were performed to examine pulmonary function. Histological and molecular analysis was performed to assess alveolar and extracellular matrix (ECM) morphology, along with gene expression of connective tissue growth factor (CTGF), IL-8, and CCL-2. ITBS attenuated the functional effect of hyperoxia-induced lung injury and limited the change to respiratory system impedance, measured using the forced oscillation technique. Treatment effects were most obvious in the small airways, with significant effects on small airway resistance and small airway reactance. In addition, ITBS mitigated the decrease in inspiratory capacity and static compliance. ITBS restricted alveolar septal thickening without altering the mean linear intercept and mitigated hyperoxia-induced remodeling of the ECM. These structural changes were associated with improved inspiratory capacity and lung compliance. Gene expression of CTGF, IL-8, and CCL-2 was significantly downregulated in the lung. Treatment with ITBS shortly after delivery attenuated the functional and structural consequences of hyperoxia-induced lung injury to day 7 of life in the preterm rabbit.