Quality control of equipment in home mechanical ventilation: a European survey.

Quality control of the equipment used in home mechanical ventilation is necessary in order to ensure that patients safely and accurately receive the prescribed ventilatory support. The aim of this study was to carry out a survey on the quality-control procedures in different centres and countries. The survey was carried out in the context of a European Commission Concerted Action covering 16 European countries. The study was extensive and detailed, involving 326 centres, which provided home ventilation to >20,000 patients. The survey showed that: 1) ventilator servicing was mainly carried out by external companies (62% of centres), with a servicing frequency ranging 3-12 months; 2) interaction between servicing companies and prescribers was limited (only 61% of centres were always informed of major incidents); 3) participation of centres in equipment quality control was poor (only 56% of centres assessed that patients/caregivers correctly cleaned/maintained the ventilator); and 4) centres were insufficiently aware of vigilance systems (only 23% of centres). Moreover, the data showed considerable inter- and intra-country differences. The size of the centre was an important determinant of many of these quality-control aspects. This survey provides information that will enable the European Commission Concerted Action to formulate recommendations on procedures for home-ventilator quality control.

Patterns of home mechanical ventilation use in Europe: results from the Eurovent survey.

The study was designed to assess the patterns of use of home mechanical ventilation (HMV) for patients with chronic respiratory failure across Europe. A detailed questionnaire of centre details, HMV user characteristics and equipment choices was sent to carefully identified HMV centres in 16 European countries. A total of 483 centres treating 27,118 HMV users were identified. Of these, 329 centres completed surveys between July 2001 and June 2002, representing up to 21,526 HMV users and a response rate of between 62% and 79%. The estimated prevalence of HMV in Europe was 6.6 per 100,000 people. The variation in prevalence between countries was only partially related to the median year of starting HMV services. In addition, there were marked differences between countries in the relative proportions of lung and neuromuscular patients using HMV, and the use of tracheostomies in lung and neuromuscular HMV users. Lung users were linked to a HMV duration of <1 yr, thoracic cage users with 6-10 yrs of ventilation and neuromuscular users with a duration of > or =6 yrs. In conclusion, wide variations exist in the patterns of home mechanical ventilation provision throughout Europe. Further work is needed to monitor its use and ensure equality of provision and access.

Longitudinal changes in the nature, severity and frequency of COPD exacerbations.

Exacerbations are an important feature and outcome measure in chronic obstructive pulmonary disease (COPD), but little is known about changes in their severity, recovery, symptom composition or frequency over time. In this study 132 patients (91 male; median age 68.4 yrs and median forced expiratory volume in one second (FEV1) 38.4% predicted) recorded daily symptoms and morning peak expiratory flow. Patients were monitored for a median of 918 days and 1,111 exacerbations were identified. Patients with severe COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) category III, n=38) had an annual exacerbation frequency of 3.43 x yr(-1), 0.75 x yr(-1) higher than those with moderate COPD (GOLD II, n=94). Exacerbation frequency did not change significantly during the study. At exacerbation onset, symptom count increased to 2.23, relative to a baseline of 0.36 set 8-14 days previously, and this increase rose by 0.05 x yr(-1). Recovery to baseline levels in symptoms and FEV1 took longer (0.32 and 0.55 days x yr(-1)). Sputum purulence at exacerbation became more prevalent over time by 4.1% x yr(-1) from an initial value of 17%. The results of this study suggest that over time, individual patients have more symptoms during exacerbations, with an increased chance of sputum purulence and longer recovery times.

Longitudinal changes in the nature, severity and frequency of COPD exacerbations

Exacerbations are an important feature and outcome measure in chronic obstructive pulmonary disease (COPD), but little is known about changes in their severity, recovery, symptom composition or frequency over time. In this study 132 patients (91 male; median age 68.4 yrs and median forced expiratory volume in one second (FEV1) 38.4% predicted) recorded daily symptoms and morning peak expiratory flow. Patients were monitored for a median of 918 days and 1,111 exacerbations were identified. Patients with severe COPD (Global Initiative for Chronic Obstructive Lung Disease (GOLD) category III, n=38) had an annual exacerbation frequency of 3.43·yr–1, 0.75·yr–1 higher than those with moderate COPD (GOLD II, n=94). Exacerbation frequency did not change significantly during the study. At exacerbation onset, symptom count increased to 2.23, relative to a baseline of 0.36 set 8–14 days previously, and this increase rose by 0.05·yr–1. Recovery to baseline levels in symptoms and FEV1 took longer (0.32 and 0.55 days·yr–1). Sputum purulence at exacerbation became more prevalent over time by 4.1%·yr–1 from an initial value of 17%. The results of this study suggest that over time, individual patients have more symptoms during exacerbations, with an increased chance of sputum purulence and longer recovery times.

Airway epithelial inflammatory responses and clinical parameters in COPD.

This study examined inflammatory responses from primary cultured human bronchial epithelial cells in chronic obstructive pulmonary disease (COPD) and the clinical factors modulating them. Epithelial cells from bronchoscopic biopsies from 14 patients with COPD ((mean +/- SD) age 74.6 +/- 5.7 yrs, forced expiratory volume in one second (FEV1) 1.21 +/- 0.36 L, FEV1 %, predicted 51.1 +/- 15.8%, 51.5 +/- 24.0 pack-yrs of smoking, inhaled steroid dosage 1237.5 +/- 671.0 microg x day(-1), Medical Research Council (MRC) dyspnoea score 3.18 +/- 1.33) and eight current/exsmokers with normal pulmonary function (age 60.4 +/- 13.5 yrs, FEV1 2.66 +/- 1.27 L, FEV1 % pred 89.6 +/- 17.7%, 49 +/- 44 pack-yrs of smoking, MRC dyspnoea score 1 +/- 0) were grown in primary culture and exposed to 50 ng x mL(-1) tumour necrosis factor-alpha. Stimulated COPD cells produced significantly more interleukin (IL)-6 at 24 and 48 h, and IL-8 at 6 and 24 h than unstimulated COPD cells. This response was not seen in cells from current/exsmokers. IL-6 and IL-8 production was lower in COPD patients taking inhaled steroids. Following an inflammatory stimulus, bronchial epithelial cells in chronic obstructive pulmonary disease show a significant cytokine response not seen in smokers with normal pulmonary function and this may be modified by inhaled steroid therapy.

Relationship between bacterial colonisation and the frequency, character, and severity of COPD exacerbations.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are prone to frequent exacerbations which are a significant cause of morbidity and mortality. Stable COPD patients often have lower airway bacterial colonisation which may be an important stimulus to airway inflammation and thereby modulate exacerbation frequency. METHODS: Twenty nine patients with COPD (21 men, 16 current smokers) of mean (SD) age 65.9 (7.84) years, forced expiratory volume in 1 second (FEV(1)) 1.06 (0.41) l, FEV(1) % predicted 38.7 (15.2)%, FEV(1)/FVC 43.7 (14.1)%, inhaled steroid dosage 1.20 (0.66) mg/day completed daily diary cards for symptoms and peak flow over 18 months. Exacerbation frequency rates were determined from diary card data. Induced sputum was obtained from patients in the stable state, quantitative bacterial culture was performed, and cytokine levels were measured. RESULTS: Fifteen of the 29 patients (51.7%) were colonised by a possible pathogen: Haemophilus influenzae (53.3%), Streptococcus pneumoniae (33.3%), Haemophilus parainfluenzae (20%), Branhamella catarrhalis (20%), Pseudomonas aeruginosa (20%). The presence of lower airway bacterial colonisation in the stable state was related to exacerbation frequency (p=0.023). Patients colonised by H influenzae in the stable state reported more symptoms and increased sputum purulence at exacerbation than those not colonised. The median (IQR) symptom count at exacerbation in those colonised by H influenzae was 2.00 (2.00-2.65) compared with 2.00 (1.00-2.00) in those not colonised (p=0.03). The occurrence of increased sputum purulence at exacerbation per patient was 0.92 (0.56-1.00) in those colonised with H influenzae and 0.33 (0.00-0.60) in those not colonised (p=0.02). Sputum interleukin (IL)-8 levels correlated with the total bacterial count (rho=0.459, p=0.02). CONCLUSION: Lower airway bacterial colonisation in the stable state modulates the character and frequency of COPD exacerbations.

The changing demographics of new HIV diagnoses at a London centre from 1994 to 2000.

OBJECTIVE: To document the demographic changes in new HIV diagnoses at the Royal Free Hospital, London, UK, between 1994 and 2000. DESIGN: Retrospective case note review. METHODS: Data were extracted from the Royal Free HIV database identifying new diagnoses for 1994, 1997 and 2000. All case notes were reviewed and patients were included if they had their first positive HIV test at the Royal Free Hospital, or if they first tested positive elsewhere and attended the Royal Free HIV unit for their initial HIV care. Data extracted included sex, ethnicity, age, risk factor(s) for HIV, reason for test, clinical stage of disease, CD4 count and HIV RNA viral load at diagnosis. RESULTS: One hundred and forty-four patients were identified for 1994, 136 for 1997 and 110 for 2000. Over this time period the proportion of white patients dropped from 72% (n = 104) to 48% (n = 53), P = 0.0001, whilst the proportion of black Africans rose from 24% (n = 34) to 45% (n = 49), P = 0.0004. The median CD4 count at diagnosis of the white cohort was 475 cells/microL in 1994 and 286/microL in 2000, P = 0.005, whilst in the black African patients it was 240/microL and 230/microL for the same years. CONCLUSIONS: There has been a reduction in new HIV diagnoses among the white population and a rise in the black Africans at this centre between 1994 and 2000. The clinical and immunological parameters of HIV disease have worsened over this time period for the white group, but have remained stable in the black Africans.

Clinical value and cost of a respiratory sleep-related breathing disorders screening service for snorers referred to a District General Hospital ENT department.

Sleep-related breathing disorders and snoring often co-exist in the community. We hypothesized that a significant proportion of patients referred from primary care to ENT surgeons for management of snoring might have significant sleep-related breathing disorders requiring medical management. The Respiratory Medicine Department at Whipps Cross Hospital, London, U.K. screened all such referrals using sleep questionnaires, overnight oximetry and diagnostic sleep studies where necessary as recommended by the Royal College of Physicians of London. Over 38 months, 115 patients were screened, of whom 43 (38%) had clinically significant sleep-disordered breathing. One-third were established on nasal continuous positive airway pressure ventilation and the remainder were mainly offered conservative treatment. The cost of the screening service is estimated at 14,000 Pounds for the initial year. The savings to the ENT service and the possible long-term benefits to the patients identified as having sleep-disordered breathing balance this. We conclude that screening all referred snorers for sleep-disordered breathing using a simple protocol identifies a significant number requiring medical management at a relatively low cost to the service provider.