Alan Crockett

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 7.3 kPa. Participants were randomly assigned in a 1:1 ratio by a central computer-generated system to receive oxygen or room air via a concentrator through a nasal cannula at 2 L per min for 7 days. Participants were instructed to use the concentrator for at least 15 h per day. The randomisation sequence was stratified by baseline PaO(2) with balanced blocks of four patients. The primary outcome measure was breathlessness (0-10 numerical rating scale [NRS]), measured twice a day (morning and evening). All randomised patients who completed an assessment were included in the primary analysis for that data point (no data were imputed). This study is registered, numbers NCT00327873 and ISRCTN67448752. FINDINGS 239 participants were randomly assigned to treatment (oxygen, n=120; room air, n=119). 112 (93%) patients assigned to receive oxygen and 99 (83%) assigned to receive room air completed all 7 days of assessments. From baseline to day 6, mean morning breathlessness changed by -0.9 points (95% CI -1.3 to -0.5) in patients assigned to receive oxygen and by -0.7 points (-1.2 to -0.2) in patients assigned to receive room air (p=0.504). Mean evening breathlessness changed by -0.3 points (-0.7 to 0.1) in the oxygen group and by -0.5 (-0.9 to -0.1) in the room air group (p=0.554). The frequency of side-effects did not differ between groups. Extreme drowsiness was reported by 12 (10%) of 116 patients assigned to receive oxygen compared with 14 (13%) of 108 patients assigned to receive room air. Two (2%) patients in the oxygen group reported extreme symptoms of nasal irritation compared with seven (6%) in the room air group. One patient reported an extremely troublesome nose bleed (oxygen group). INTERPRETATION Since oxygen delivered by a nasal cannula provides no additional symptomatic benefit for relief of refractory dyspnoea in patients with life-limiting illness compared with room air, less burdensome strategies should be considered after brief assessment of the effect of oxygen therapy on the individual patient. FUNDING US National Institutes of Health, Australian National Health and Medical Research Council, Duke Institute for Care at the End of Life, and Doris Duke Charitable Foundation.

Survival on long-term oxygen therapy in chronic airflow limitation : from evidence to outcomes in the routine clinical setting

Abstract

The impact of anxiety, depression and living alone in chronic obstructive pulmonary disease

Objective: This prospective longitudinal study examined whether quality of life as measured by the disease specific chronic respiratory questionnaire (CRQ) and living alone, at the time of prescription of long-term oxygen therapy (LTOT), impacted on the mortality of patients with severe chronic obstructive pulmonary disease (COPD). Methods: One-hundred and fifty-seven patients, (male:female, 74:83) with severe COPD, aged under 80 years completed the CRQ at the time of prescription of LTOT. Demographic and physiological parameters were also collected. The patients were followed in outpatient clinics after commencing LTOT. Results: Kaplan–Meier analysis of the data demonstrated a relationship between the emotional function score of the CRQ at the commencement of LTOT and survival on LTOT for female patients. Living with a partner was associated with an additional 12 months of life. When known physiological predictors of survival, the CRQ dimensions and living alone were included in a Coxs proportional hazard model, emotional function, body mass index and forced vital capacity were independent prognostic indicators for females, and arterial partial pressure of oxygen for males. Conclusion: Our results suggest that poor emotional functioning of female patients with severe COPD at the time of prescription of LTOT is associated with increased mortality.

Repeated histamine inhalation tests in asthmatic patients.

Histamine inhalation tests were performed in 12 asthmatic patients using a 2-min tidal breathing inhalation technique. The tests were repeated on separate days with 30-, 60-, and 120-min intervals between inhalation tests. On another day the inhalation tests were repeated four times with 40-min intervals between tests. The geometric mean provocative concentrations of histamine needed to cause a 20% fall in forced expiratory volume in 1 sec (PC20) for the group on the latter study day were 1.67, 1.57, and 1.55 mg/ml (p greater than 0.25) indicating no change in sensitivity to inhaled histamine with repeated testing. The results suggest that cumulative dose-response curves for drugs potentially affecting the airways or antagonizing histamine can be constructed within 1 day using histamine inhalation tests. The data also suggested that an individual PC20 result may be sensitively assessed by comparing it to a +/- 2 SD range from the mean of a series of control or placebo PC20 values.

Simplified COPD screening: validation of the PiKo-6 ® in primary care

AIMS To determine the accuracy of the forced expiratory volume ratio at one and six seconds (FEV1/FEV6) using a hand-held, expiratory flow meter (PiKo-6®, nSpire Health, Inc.) to screen for chronic obstructive pulmonary disease (COPD) in primary care settings. METHODS Current and former smokers (≥ 50 years old) with no previous respiratory diagnosis (case finding [CF] = 204 subjects) or with an asthma diagnosis (differential diagnosis [DD] = 93 subjects) were evaluated using validated questionnaires, pre-bronchodilator (BD) FEV1/FEV6 and post-BD FEV1/forced vital capacity (FVC) spirometry. RESULTS The PiKo-6® FEV1/FEV6 showed good sensitivity and specificity (areas under the Receiver Operating Characteristic curves [95% confidence intervals]: CF = 0.85 [0.79, 0.90]; DD = 0.88 [0.80, 0.96]) and exceeded the accuracy of the questionnaires. An FEV1/FEV6 cutoff < 0.75 provided optimal sensitivity (CF = 81%; DD = 86%) and specificity (CF = 71%; DD = 67%) for COPD screening. CONCLUSIONS The PiKo-6® allows simple and reliable screening for COPD which could optimise early referral for spirometry and early, targeted interventions for COPD.

The MOS SF-36 health survey questionnaire in severe chronic airflow limitation: Comparison with the Nottingham health profile

This study documents the cross-sectional, health-related quality of life (HRQOL) measures obtained at baseline for patients with severe chronic airways limitation (CAL) being assessed for home oxygen therapy (HOT) at the Flinders Medical Centre, Adelaide, South Australia. Two generic quality of life instruments, the Nottingham Health Profile (NHP) and the Medical Outcomes Study (MOS) short form 36-item questionnaire (SF-36), were administered by interview to the same patients to permit comparisons to be made between the two instruments. SF-36 mean scores were also compared with scores obtained in separate studies of a South Australian elderly general population and of groups of Australian subjects with various medical and psychiatric conditions. NHP mean scores were compared with scores from an elderly group of Adelaide residents from a household survey. HRQOL measures were obtained for 60 patients, 32 males and 28 females. At assessment for HOT, patients with severe CAL were experiencing severe impairment in their quality of life in comparison to age-matched South Australian norms, with physical disability the major limitation. There were several significant correlations between the domains of the SF-36 and the NHP which were predominantly gender-specific. Only small decrements in mental health were found with the SF-36 questionnaire. The SF-36 and the NHP appear to provide discrepant information for severely disabled CAL patients for the subjective domains of emotional and mental health.

A pilot study to evaluate Australian predictive equations for the impulse oscillometry system

Background and objective:  Impulse oscillometry (IOS) measures respiratory function during normal breathing by transmitting mixed frequency rectangular pressure impulses down the airways and measuring the resultant pressure and flow relationships, which describe the mechanical parameters of the lungs. Respiratory impedance and its components, airways resistance and reactance, at a range of frequencies from 0.1 to 150 Hz are calculated by computer analysis. The IOS software generates predictive normal values for each of the parameters measured, including total airway resistance (R5), proximal airway resistance (R20) and peripheral capacitive reactance (X5). However, these values are based on German data and no other Caucasian data or Australian normative data exist.

Combination bronchodilator therapy in asthma

This study has compared the short-term bronchodilator effects of inhaled anticholinergic (ipratropium bromide) and sympathomimetic (fenoterol) agents alone and in combination in 18 asthmatic patients. the study was of double-blind, placebo-controlled, crossover design. The combination of 60 micrograms ipratropium bromide and 200 micrograms of fenoterol had a greater bronchodilator effect than lower dose combinations or either drug alone. Small but significant gains may be made with combination inhaled bronchodilator therapy.

The impact of alexithymia on asthma patient management and communication with health care providers: a pilot study.

Background and objectives. Alexithymia is a personality trait associated with difficulty identifying and verbalizing feelings. It has been associated with poorly controlled asthma and near-fatal asthma. The primary objectives were to (1) determine the prevalence of alexithymia in a group of moderate to severe asthmatics who attended an Outpatient Clinic; and (2) investigate the relationship between alexithymia and asthma control, management, and communication. Methods. Twenty-five moderate to severe asthma patients were recruited from the Royal Adelaide Hospital Outpatient Respiratory Clinic. Participants were either mailed the questionnaire pack or completed it after a clinic appointment. Existing validated questionnaires were used to collect data. The primary outcome measures were alexithymia, asthma control, adherence to medication; patient satisfaction with communication with health care providers and health-related quality of life. Data were analyzed using Pearson correlations, linear regression and analysis of variance (ANOVA) in SPSS. A p value ≤ 0.05 was required for statistical significance. Results. A total of 11 male (44%) and 14 female (56%) patients with moderate to severe persistent asthma (mean age 44 years ± 11) participated. Alexithymia scores ranged between 23.0-76.0 ( = 48.3, SD = 13.2); 12% of participants reported high alexithymia scores, 32% reported borderline alexithymia scores, and 56% reported low alexithymia scores. Alexithymia mean scores were not statistically different across sociodemographic variables. A higher alexithymia score was associated with worse asthma control score (r = 0.57, p < 0.01) (where higher asthma control scores indicate worse asthma control); poor adherence (p = 0.03), and worse quality of life (r = - 0.65, p < 0.01). Alexithymia score was not correlated with satisfaction with communication (r = − 0.27, p = 0.2).), or the number of hospitalizations for asthma (p = 0.25). Conclusions. This is the first study to investigate relationships between alexithymia, asthma control, asthma management and communication with health care professionals. The study reaffirms associations between alexithymia and asthma control, but a larger sample size is needed to determine the impact of alexithymia on self-management and provision of clinical care for asthma.

UNLOCK: Uncovering and Noting Long-term Outcomes in COPD to enhance knowledge.

a Department of Public Health and Primary Care, Leiden University Medical Center, the Netherlands b Department of Public Health and Caring Sciences, Family Medicine and Clinical Epidemiology, Uppsala University,Sweden c Spanish Primary Care Respiratory Group (GRAP), Spain. d Department of Public Health and General Practice, Norwegian University of Science and Technology, Norway e School of Population Health & Clinical Practice, University of Adelaide, Australia f University of Alberta, Canada g International Primary Care Respiratory Group (IPCRG), United Kingdom h Peninsula Medical School, University of Plymouth, United Kingdom i Department of General Practice, University Medical Center Groningen, the Netherlands j Centre of Academic Primary Care, University of Aberdeen, United Kingdom