What determines immediate use of invasive ventilation in patients with COPD?

BACKGROUND: The choice between non-invasive ventilation (NIV) and invasive ventilation in patients with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) may be irrational. The aim of this study was to examine those patient characteristics, and circumstances deemed important in the choice made between NIV and invasive ventilation in the intensive care unit (ICU). METHODS: We first examined 95 admissions of AECOPD patients on nine ICUs and identified variables associated with invasive ventilation. Thereafter, a questionnaire was sent to ICU personnel to study the relative importance of different factors with a possible influence on the decision to use invasive ventilation at once. RESULTS: Univariable analysis showed that increasing age [odds ratio (OR) 1.06 per year] and increasing body mass index (BMI) (OR 1.11 per kg/m(2) ) were associated with immediate invasive ventilation, while there was no such association with arterial blood gases or breath rate. BMI was the only factor that remained associated with immediate invasive ventilation in the multivariable analysis [OR 1.12 (95% confidence interval 1.03-1.23) kg/m(2) ]. Ranking of responses to the questionnaire showed that consciousness, respiratory symptoms and blood gases were powerful factors determining invasive ventilation, whereas high BMI and age were ranked low. Non-patient-related factors were also deemed important (physician in charge, presence of guidelines, ICU workload). CONCLUSION: Factors other than those deemed most important in guidelines appear to have an inappropriate influence on the choice between NIV and immediate intubation in AECOPD in the ICU. These factors must be identified to further increase the appropriate use of NIV.

Overexpression of von Hippel-Lindau protein in skeletal muscles of patients with chronic obstructive pulmonary disease.

BACKGROUND: A significant number of patients with chronic obstructive pulmonary disease (COPD) exhibit skeletal muscle wasting and decreased capillary area formation, which correlate with increased mortality. AIM: To determine the molecular mechanisms mediating decreased capillary formation in COPD. METHODS: 24 patients with COPD and 12 matching controls were recruited. Patients with COPD were classified into mild, moderate and severe groups according to GOLD (global initiative for chronic obstructive lung disease) criteria. Biopsy specimens were obtained from the tibialis anterior muscle. Fibre typing and capillary formation, together with messenger RNA (mRNA) expression of hypoxia-inducible factors (HIF1alpha and HIF3alpha), vascular endothelial growth factors (VEGF-A, VEGF-B and VEGF-C isoforms) and von Hippel-Lindau (VHL) protein, were determined. VHL expression and localisation were further studied by immunohistochemistry. RESULTS: Skeletal muscle capillary formation decreased significantly with increasing disease severity. Compared with controls, a tendency to mRNA overexpression of HIF1alpha, HIF3alpha and VEGF isoforms was observed in mild and moderate COPD, which decreased at the severe stage. In contrast, skeletal muscle biopsy samples from patients with COPD exhibited significant overexpression of VHL at both the mRNA and protein level by immunohistochemistry. VHL protein was further determined to be localised to satellite cells. CONCLUSIONS: Overexpression of VHL was identified in the skeletal muscle of patients with COPD. Increased VHL activity may have a negative effect on transduction of the hypoxic signal and may contribute to decreased capillarisation in skeletal muscles of patients with COPD.

Effect of 1 year daily treatment with 400 microg budesonide (Pulmicort Turbuhaler) in newly diagnosed asthmatics.

The aim of this study was to investigate whether treatment with a low daily dose of 400 microg inhaled budesonide (Pulmicort Turbuhaler) in newly diagnosed asthmatics could influence the course of asthma. Seventy five adult patients, mostly with mild asthma, diagnosed during the previous year and bronchial hyperresponsiveness, participated in a double-blind, randomized, parallel-group multicentre study. They were treated with budesonide 200 microg b.i.d. or placebo, delivered via Turbuhaler for 12 months and followed-up for another 6 months without inhaled steroid treatment. Airway function, symptom scores, reactivity to histamine and inflammatory indices in blood were assessed. The mean increase in morning peak expiratory flow (PEF) was 28 L x min(-1) after budesonide treatment compared with no increase in the placebo group (p=0.011). The provocative dose of histamine causing a 20% fall in forced expiratory volume in one second (PD20) (geometric mean) increased in the budesonide group by approximately two doubling dose steps, but not in the placebo group (p=0.0003). The difference between groups with regard to improvement in asthma symptom scores and inflammatory indices did not reach statistical significance. During the 6 month follow-up, the PEF values of the patients who had previously been treated with budesonide decreased by 18 L x min(-1) while the PD20 decreased by approximately one doubling dose step. In conclusion, early treatment with a low dose of budesonide improves airway function and decreases bronchial responsiveness, but the improvements are short-lasting without continued treatment.