Grading the severity of obstruction in patients with chronic obstructive pulmonary disease and morbid obesity.

AIM: To evaluate the severity of airway obstruction in patients affected by chronic obstructive pulmonary disease (COPD) in the presence of concomitant restriction due to morbid obesity. METHODS: Lung function test, six-minute walking distance (6MWD) test, body mass index measurement (BMI), and determination of dyspnoea using the Modified Medical Research Council Dyspnoea Scale (MMRC) were performed on each patient referred to our department according to their individual respiratory diagnosis or symptoms. Analysis was performed on smokers or ex-smokers patients, with both dyspnoea and chronic productive cough, showing non fully reversible airflow obstruction, with normal-weight (NW: BMI 22 to 24 kg/m2) or morbid-obesity (MO: BMI > or = 40 kg/m2). RESULTS: In 33 COPD patients, spirometric data differ between NW and MO only in fixed FEV1/FVC ratio (50 +/- 9 and 62 +/- 7, respectively; p = 0.0001) and FEV1/SVC % of predicted (57 +/- 15 and 71 +/- 11, respectively; p = 0.005). Furthermore, SVC was found to exceed FVC only in NW (2.82 +/- 0.7 L and 2.08 +/- 0.9 L, respectively; p = 0.03). NW and MO differ significantly also in MMRC (3.4 +/- 0.9 vs 2.4 +/- 1, respectively; p = 0.004), 6MWD in metres (226 +/- 100 and 331 +/-110, respectively, p = 0.007), 6MWD as % predicted (49 +/- 22 and 81 +/- 23, respectively; p = 0.0003), and BODE index (5.8 +/- 2 and 3.6 +/- 2, respectively; p = 0.003). CONCLUSIONS: There is a significant overgrading of obstruction in morbidly obese patients affected by COPD. Therefore, we suggest that an alternative grading system be used for patients with mixed ventilatory dysfunction.

Prevalence of airflow obstruction according GOLD, ATS and ERS criteria in symptomatic ever-smokers referring to a pulmonary rehabilitation department.

AIM: To evaluate in a Pulmonary Rehabilitation (PR) setting the prevalence of airflow obstruction (AO) in either current or former smokers > or = 45 years old both with dyspnoea and with chronic productive cough, using European Respiratory society (ERS) statement (FEV1/SVC < 88 and < 89% predicted in men and women, respectively), American Thoracic Society (ATS) statement (FEV1/FVC < 75%), and Global Initiative for Chronic Obstructive Lung Disease (GOLD) statement (FEV1/FVC < 70%). METHODS: Lung function tests were performed in each patient who was referred to our PR department due to respiratory diagnosis or symptoms. For analysis, in patients showing AO we used post-bronchodilator lung function values. RESULTS: In 184 ever-smoker patients with symptoms of chronic obstructive pulmonary disease (COPD), the prevalence rates of AO were as follows: ERS = 89.7%, ATS = 76.6%, and GOLD = 63.6%. Patients with AO according ERS criteria showing moderate to severe (M/S) obstruction (i.e., FEV1 < 70% predicted) were 119. Patients with ERS M/S AO but without AO using either ATS or GOLD criteria were 8.4% and 19.3%, respectively. CONCLUSIONS: Prevalence of AO is highly dependent on which guidelines it is based. ATS and particularly GOLD statement can cause a large under-diagnosis even of moderate to severe COPD. Diagnosis of COPD may be overlooked if SVC is not performed.

[Sleep-disordered breathing and occupational medicine: considerations on three clinical cases]. / Disturbi respiratori del sonno e medicina del lavoro: considerazioni su tre casi clinici.

Three subjects suffering from sleep-disordered breathing are described. Two of them (a 37-year-old lorry driver with obstructive sleep apnea, and a 47-year-old bricklayer with upper airway resistance syndrome) had suffered several accidents at work in few months, due to daytime sleepiness. The third patient (45-year-old) had developed (central and obstructive) sleep apnea after having been exposed to organic solvents for 15 years as a painter. In all the three subjects, polysomnography led to correct diagnosis, and nocturnal ventilotherapy with nasal CPAP (continuous positive airway pressure) considerably improved the clinical picture. The cases presented illustrate the twofold interest of sleep-disordered breathing for Occupational Medicine: on the one hand, these syndromes may reduce job performance and increase the accident risk; on the other hand, they may recognize as a risk factor the occupational exposure to solvents.

Weakness of respiratory and skeletal muscles after a short course of steroids in patients with acute lung rejection.

There have been occasional reports of acute respiratory and skeletal muscle weakness in intensive care unit patients treated with massive doses of corticosteroids. However, in this setting the concomitant use of other drugs may have influenced the finding. In this study the effects of 5 days of treatment with high doses of steroids in consecutive patients with acute lung rejection after transplantation were systematically evaluated. Maximal inspiratory pressure during phrenic nerve stimulation and peak torque of isokinetic contraction of the quadriceps and hamstring muscles were measured objectively. Compared to the pretreatment condition, approximately 45% of patients showed acute generalised muscle weakness that recovered after approximately 2 months. This demonstrates muscle weakness induced by steroids within patients.

Respiratory muscles in chronic obstructive pulmonary disease and asthma.

Chronic obstructive pulmonary disease (COPD) and asthma are characterized by airflow obstruction and significant increase of respiratory muscle workload, with concrete risk of ventilatory pump failure. Respiratory muscles, the main component of this pump, undergo structural and functional changes during the course of these diseases. Aim of the present paper is to analyze modifications of respiratory muscles in COPD and asthma. An analysis of the most important controlled clinical studies released during the past years was carried out. The patients suffered from chronic obstructive pulmonary disease and asthma. In COPD, respiratory muscles have to cope with an increased load, an intrinsic weakness and a mechanical disadvantage, especially in the diaphragmatic length-force relationship; in patients with acute asthma, the main features are a massive hyperinflation and a persistent inspiratory muscle activity during expiration. Modifications of respiratory muscles deserve great consideration not only for the complete comprehension of the underlying physiopathologic aspects of these diseases, but also for the optimal clinical management: a reduced pulmonary hyperinflation in COPD place the respiratory muscles in a better position of the force-length curve while great care must be payed to the metabolic and nutritional aspects. During asthmatic crisis respiratory muscles are subjected to a sort of intense training but anyway persistence of bronchospasm in most severe attacks can lead to exhaustion of the ventilatory pump and need of mechanical ventilatory support.