Nocturnal hypoxaemia is associated with adverse outcomes in interstitial lung disease.

Background And Objective: Sleep-disordered breathing (SDB) has been reported as highly prevalent in idiopathic pulmonary fibrosis (IPF) and other interstitial lung disease (ILD) populations. Nocturnal oxygen desaturation (NOD), or the total sleep time spent with SpoO < 90% (TST < 90), can occur both with and without associated apnoeas, and is common in ILD. This study aimed to characterize abnormal SDB and extent of TST < 90 in ILD patients and evaluate relationships between TST < 90 and markers of disease severity, development of pulmonary hypertension (PH) and mortality.

Airway closure on imaging relates to airway hyperresponsiveness and peripheral airway disease in asthma.

The regional pattern and extent of airway closure measured by three-dimensional ventilation imaging may relate to airway hyperresponsiveness (AHR) and peripheral airways disease in asthmatic subjects. We hypothesized that asthmatic airways are predisposed to closure during bronchoconstriction in the presence of ventilation heterogeneity and AHR. Fourteen asthmatic subjects (6 women) underwent combined ventilation single photon emission computed tomography/computed tomography scans before and after methacholine challenge.

Gas exchange in disease: asthma, chronic obstructive pulmonary disease, cystic fibrosis, and interstitial lung disease.

Ventilation-perfusion (VA/Q) inequality is the underlying abnormality determining hypoxemia and hypercapnia in lung diseases. Hypoxemia in asthma is characterized by the presence of low VA/Q units, which persist despite improvement in airway function after an attack. This hypoxemia is generally attenuated by compensatory redistribution of blood flow mediated by hypoxic vasoconstriction and changes in cardiac output, however, mediator release and bronchodilator therapy may cause deterioration.

Sodium cromoglycate and eformoterol attenuate sensitivity and reactivity to inhaled mannitol in subjects with bronchiectasis.

Background And Objective: Dry powder mannitol has the potential to be used to enhance clearance of mucus in subjects with bronchiectasis. A reduction in FEV1 has been recorded in some subjects with bronchiectasis after inhaling mannitol. The aim of this study was to investigate if pre-medicating with either sodium cromoglycate (SCG) or eformoterol could inhibit this reduction in FEV1.

Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: a double-blind, randomised controlled trial.

Background: Palliative oxygen therapy is widely used for treatment of dyspnoea in individuals with life-limiting illness who are ineligible for long-term oxygen therapy. We assessed the effectiveness of oxygen compared with room air delivered by nasal cannula for relief of breathlessness in this population of patients.

Methods: Adults from outpatient clinics at nine sites in Australia, the USA, and the UK were eligible for enrolment in this double-blind, randomised controlled trial if they had life-limiting illness, refractory dyspnoea, and partial pressure of oxygen in arterial blood (PaO(2)) more than 7.

Iatrogenic osteoporosis, bilateral HIP osteonecrosis, and secondary adrenal suppression in an HIV-infected man receiving inhaled corticosteroids and ritonavir-boosted highly active antiretroviral therapy.

Objective: To report the first case of severe osteoporosis associated with a vertebral pathologic fracture and osteonecrosis of femoral heads in an HIV-infected man receiving inhaled corticosteroids and ritonavir-boosted antiretroviral therapy.

Methods: We describe an HIV-infected man with severe osteoporosis, bilateral hip osteonecrosis, and secondary adrenal suppression, including detailed clinical, laboratory, and radiographic data, and review the related literature.

Results: A 60-year-old man with a 15-year history of HIV infection and a medical history of long-standing bronchiectasis treated with inhaled corticosteroids and hypogonadism treated with testosterone was referred to the endocrinology clinic after experiencing an osteoporotic vertebral fracture.

Beneficial effect of inhaled mannitol and cough in asthmatics with mucociliary dysfunction.

Asthmatics with overproduction of mucus that is viscous and sticky have impaired mucociliary clearance (MCC) leading to mucus plugs, and airway obstruction. Inhaled mannitol improves mucus clearance in other hypersecretory diseases. This study investigated the effect of mannitol and cough in asthmatics with mucociliary dysfunction.

Effect of mannitol and repetitive coughing on the sputum properties in bronchiectasis.

Unlabelled: Mucociliary clearance increases with increasing doses of mannitol and clearance is enhanced when mannitol inhalation is followed by repetitive voluntary coughing. The aim of the study was to investigate: 1) the effect of increasing doses of mannitol and repetitive coughing on the sputum physical properties; 2) if the changes in sputum properties can predict the efficacy of mucus clearance measured by radioaerosol technique in bronchiectasis patients. Sputum was collected from 14 patients, age: 63+/-6yr, who participated on the mucociliary and cough clearance studies at baseline, with mannitol (160, 320 and 480mg) and control (Daviskas et al.

Gas exchange in stable patients with moderate-to-severe lung disease from cystic fibrosis.

Background: Studies using the multiple inert gas elimination technique (MIGET) to characterise the mechanisms of impaired gas exchange in CF, provide conflicting results on the importance of ventilation-perfusion (VA/Q) inequality over shunt. We hypothesise that the mechanisms of gas exchange abnormality have changed with changing CF management over the last two decades.

Methods: Detailed gas exchange was evaluated by MIGET with venous sampling in stable patients, age > 20 years, FEV1% predicted < or = 50.

Pulmonary gas exchange response to exercise- and mannitol-induced bronchoconstriction in mild asthma.

Both exercise (EIB) and mannitol challenges were performed in asthmatic patients to assess and compare their pulmonary gas exchange responses for an equivalent degree of bronchoconstriction. In 11 subjects with EIB [27 +/- 4 (SD) yr; forced expiratory volume in 1 s (FEV(1)), 86 +/- 8% predicted], ventilation-perfusion (Va/Q) distributions (using multiple inert gas elimination technique) were measured 5, 15, and 45 min after cycling exercise (FEV(1) fall, 35 +/- 12%) and after mannitol (33 +/- 10%), 1 wk apart. Five minutes after EIB, minute ventilation (Ve; by 123 +/- 60%), cardiac output (Qt, by 48 +/- 29%), and oxygen uptake (Vo2; by 54 +/- 25%) increased, whereas arterial Po2 (Pa(O2); by 14 +/- 11 Torr) decreased due to moderate Va/Q imbalance, assessed by increases in dispersions of pulmonary blood flow (log SD(Q); by 0.

Quantifying amount of adsorption of levothyroxine by percutaneous endoscopic gastrostomy tubes.

Background: It has been the authors' clinical experience that hypothyroid patients who achieve a euthyroid state on a steady dose of oral levothyroxine often become hypothyroid over time if the medication is given via a feeding tube. The authors hypothesize that the tubing and enteral feeds may adsorb a significant percentage of the levothyroxine and thereby reduce its bioavailability. To the authors' knowledge, no previous research has been reported on this subject.

Electroencephalographic arousals during sleep do not alter the pressor response to Cheyne-Stokes respiration in subjects with chronic heart failure.

This study examined the influence of electroencephalographic (EEG) arousal on the magnitude and morphology of the pressor response to Cheyne-Stokes respiration (CSR) in subjects with congestive heart failure (CHF). Thirteen subjects with stable CHF (left ventricular ejection fraction, 26 +/- 7%) and CSR (apnea-hypopnea index 52 +/- 15 h(-1)) underwent overnight polysomnography with beat-to-beat measurement of systemic arterial blood pressure (BP). CSR events were divided into those with or without an EEG arousal defined according to the criteria of the American Sleep Disorders Association.

Mucociliary clearance in patients with chronic asthma: effects of beta agonists.

Objective: Chronic asthma is characterized by airway inflammation, mucus hypersecretion and impaired mucociliary clearance (MCC). We investigated baseline MCC and the acute effect of terbutaline in chronic asthmatics with sputum production while on long-term treatment with salmeterol in combination with inhaled corticosteroids (ICS).

Methodology: MCC was measured at baseline and in response to 1 mg terbutaline (or placebo) on three visits over 80 min in 16 asthmatics (52+/-13 years of age).

Adult domiciliary oxygen therapy. Position statement of the Thoracic Society of Australia and New Zealand.

Patients with chronic obstructive pulmonary disease and a stable daytime PaO2 of < or = 55 mmHg (7.3 kPa) live longer and have a better quality of life if provided with long-term continuous oxygen therapy. It is reasonable to offer continuous oxygen therapy also to patients with other lung diseases that cause chronic hypoxaemia.

Gas exchange and exercise tolerance following bullectomy.

This study evaluates the physiological responses to giant bullectomy. A 42-year-old female with bilateral giant bullae presented with dyspnoea and exercise limitation. At baseline and 3 months after bullectomy she had tests of lung function; exercise capacity via a symptom-limited cycle test and a 6-min walk test (6MWT).

Inhaled mannitol for the treatment of mucociliary dysfunction in patients with bronchiectasis: effect on lung function, health status and sputum.

Objective: Inhaled mannitol increases mucus clearance in patients with bronchiectasis by an unclear mechanism. The effect of mannitol on lung function, health status and sputum properties was investigated.

Methodology: Nine patients with bronchiectasis inhaled 400 mg of mannitol once daily for 12 days.

Changes in lung deposition of aerosols due to hygroscopic growth: a fast SPECT study.

Our objective was to use rapid dynamic SPECT to study the effect of hygroscopic growth on aerosol deposition in the lung. Six healthy volunteers inhaled radiolabeled ((99m)Tc-DTPA) saline aerosols of two different droplet sizes (MMAD Small 3.2 +/- 0.