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Objective: Sniff nasal inspiratory pressure (SNIP), a useful tool for the assessment of diaphragm function in patients with Amyotrophic Lateral Sclerosis (ALS), is usually performed together with lung function tests. The aim of this study was to evaluate whether SNIP results are influenced by the order of performance of the tests. Methods: 103 consecutive patients (65% males, 80% spinal onset) were recruited. The highest value of up to 10 sniffs, was recorded before (SNIPT0) and after (SNIPT1) the assessment of lung function, peak cough (PCF), and peak expiratory flow (PEF). Results: Mean and median values were respectively 31.10 and 26.00 cm H2O for SNIPT0 and 28.93 and 25.00 cm H2O for SNIPT1 (p < 0.001). The median value of (SNIPT1 − SNIPT0)/SNIPT0% was −7.10. Patients showing post lung function SNIP values above the median were included in Group 1 (51%), the others in group 2 (49%). Group 2 showed more severe baseline ventilatory restriction and reduction in PCF than Group 1. Positive direct relationships were found between SNIPT0 and SNIPT1 (coefficient β = 0.95, p < 0.001), and forced vital capacity and forced expiratory volume at one second. Conclusions: 50/103(49%) patients with ALS show a significant reduction in SNIP when assessed shortly after the performance of lung function tests. These patients suffer from more severe ventilatory restriction than patients not showing the reduction. Our findings suggest standardizing the order of respiratory tests during the follow up in order to avoid to misestimate the real strength of inspiratory muscles. [ABSTRACT FROM AUTHOR]

Aim: To assess whether an e-nose could discriminate between subjects affected by allergic rhinitis with and without concomitant extrinsic asthma, as well as from healthy controls, in terms of exhaled VOC-profile. Methods: Fourteen patients with Extrinsic Asthma and Allergic Rhinitis (AAR), 14 patients with Allergic Rhinitis without asthma (AR) and 14 healthy controls (HC) participated in a cross-sectional study. Exhaled breath was collected by a standardized method and sampled by an e-nose (Cyranose 320). Raw data were reduced by Principal component analysis and analyzed by canonical discriminant analysis. Cross-validation accuracy (CVA) and Receiver Operating Characteristic(ROC)-curves were calculated. External validation in newly recruited patients (7 AAR, 7 AR and 7 HC) was tested using the previous training model. Results: Breathprints of patients with AR clustered from those with AAR (CVA = 85.7%), as well as HC (CVA = 82.1%). Breathprints from AAR were also separated from those of HC (CVA = 75.0%). External validation confirmed the above findings. Conclusions: An e-nose can discriminate exhaled breath from subjects with allergic rhinitis with and without extrinsic asthma, which represent two different diseases with partly overlapping features. This supports the view of using breath profiling to diagnose asthma also in patients with allergic rhinitis. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that rapidly involves the respiratory system, leading to persistent respiratory insufficiency. Neuromuscular respiratory weakness is also responsible for sleep disordered breathing (SDB), which occurs at an early stage of ALS. Maximal sniff nasal-inspiratory pressure (SNIP) is a sensitive test to early disclose respiratory muscle decline. The aim of this study was to evaluate the role of the SNIP test, compared to FVC, as a marker of SDB in ALS. We studied 31 (18 males) patients with ALS, who were divided into two groups according to the SNIP test value. Ten patients who showed a SNIP value higher than 60 cmH2O were considered as group 1. Twenty-one patients exhibited a SNIP lower than 60 cmH2O and were included in group 2. Both groups of patients were also investigated with nocturnal sleep study. A linear correlation between lower SNIP value and reduced nocturnal SaO2 in patients with a SNIP value less than 60 cmH2O ( n == 21; r == 0.449; p == 0.04) was found. A negative correlation between SNIP and time spent in SaO2 below 90% (TST90) ( n == 21; r == −0.584; p == 0.0054), and between SNIP and oxyhaemoglobin desaturation index (ODI, events/hour) ( n == 21; r == −0.458; p == 0.0368) was also established in all the patients of group 2, while, in this group, FVC did not correlate with any nocturnal parameter observed. A positive correlation between SNIP and PaO2 at baseline of the entire population of patients ( n == 31; r == 0.614; p < 0.001) was also seen. In conclusion, the results of this preliminary study show that SNIP < 60 cmH2O might be considered an early predictor of SDB in ALS. [ABSTRACT FROM AUTHOR]

Exposure to high oxygen concentration produces toxicity by tree radical release. We aimed to study: whether stable chronic obstructive pulmonary disease (COPD) patients present an unbalance in the blood redox status; the effect of oxygen administration on blood redox balance; the efficacy of N-acetyl-cysteine (NAC) treatment against the oxidative stress-induced by oxygen administration and whether it is dose-related. To this, 45 stable state III COPD patients were recruited and reduced glutathione (GSH) and oxidised glutathione (GSSG) in erythrocytes and thiol proteins (P-SH) and carbonyl proteins (PC) in both erythrocytes and plasma were evaluated. All COPD patients underwent 21/m oxygen for 18 h and NAC at 1200 or 1800 mg/day or placebo for 48 h starring with oxygen administration. Blood samples were collected at basal conditions, after 8 and 18 h of oxygen administration and 24 h after oxygen withdrawal. Results: COPD patients present an unstable redox equilibrium mainly due to plasma sulphydryl protein depletion. Oxygen administration oxidize erythrocyte GSH, decrease P-SH and increase PC levels in both plasma and erythrocytes. NAG administration counteract the oxidative stress and at the highest dose completely prevent protein oxidation. In conclusion, stable state III COPD patients present an unstable redox balance; long term low flow oxygen administration induces systemic oxidative stress, which is prevented by NAC treatment. [ABSTRACT FROM AUTHOR]