Biswajit Chakrabarti

Paradoxical movement of the lower ribcage at rest and during exercise in COPD patients

Paradoxical inward displacement of the costal margin during inspiration is observed in many chronic obstructive pulmonary disease patients at rest but its importance is unclear. The current authors studied 20 patients (forced expiratory volume in one second 32.6±11.7, functional residual capacity 186±32% predicted) and 10 healthy controls at rest and during symptom-limited incremental exercise. With optoelectronic plethysmography, the phase shift between pulmonary and abdominal ribcage volumes and the percentage of inspiratory time the ribcage compartments moved in opposite directions were quantified, using control data to define the normal range of movement. Eight patients showed lower ribcage inspiratory paradox at rest (P+), while 12 patients did not (P-). This was unrelated to resting lung function or exercise tolerance. Total end-expiratory chest wall volume (EEVcw) increased immediately when exercise began in P+ patients, but later in exercise in P- patients. This difference in EEVcw was mainly due to a greater increase of end-expiratory pulmonary ribcage volume in P+ patients. During exercise, dyspnoea increased similarly in the two groups, while leg effort increased more markedly in the patients without paradox. In conclusion, lower ribcage paradox at rest is reproducible and associated with early-onset hyperinflation of the chest wall and predominant dyspnoea at end-exercise. When paradox is absent, the sense of leg effort becomes a more important symptom limiting exercise.

Hyperglycaemia as a predictor of outcome during non-invasive ventilation in decompensated COPD

Rationale: Hyperglycaemia predicts a poor outcome in Intensive Care Unit (ICU) patients. Whether this is true for respiratory failure necessitating non-invasive ventilation (NIV) is not known. Objectives: To determine whether hyperglycaemia within 24 h of admission independently predicts outcome of NIV during acute decompensated ventilatory failure complicating chronic obstructive pulmonary disease (COPD) exacerbations. Methods: Patients with COPD presenting with acute hypercapnic respiratory failure at University Hospital Aintree between June 2006 and September 2007 and receiving NIV within 24 h of admission were studied prospectively. Random blood glucose levels were measured before NIV administration. Results: 88 patients (mean baseline pH 7.25, PaCO2 10.20 kPa, and PaO2 8.19 kPa) met the inclusion criteria, with NIV normalising arterial pH off therapy in 79 (90%). After multivariate logistic regression, the following predicted outcome: baseline respiratory rate (OR 0.91; 95% CI 0.84 to 0.99), random glucose ⩾7 mmol/l (OR 0.07; 95% CI 0.007 to 0.63) and admission APACHE II (Acute Physiology and Chronic Health Evaluation II) score (OR 0.75; 95% CI 0.62 to 0.90). The combination of baseline respiratory rate (RR) <30 breaths/min and random glucose <7 mmol/l increased prediction of NIV success to 97%, whilst use of all three factors was 100% predictive. Conclusions: In acute decompensated ventilatory failure complicating COPD, hyperglycaemia upon presentation was associated with a poor outcome. Baseline RR and hyperglycaemia are as good at predicting clinical outcomes as the APACHE II score. Combining these variables increases predictive accuracy, providing a simple method of early risk stratification.

Risk assessment of pneumothorax and pulmonary haemorrhage complicating percutaneous co-axial cutting needle lung biopsy

INTRODUCTION The primary aim of this study was to evaluate the ability of radiologists to accurately estimate pneumothorax and pulmonary haemorrhage during percutaneous co-axial cutting needle CT-guided lung biopsy. METHODOLOGY Patients undergoing cutting needle lung biopsy during the study period were identified; the path taken by the cutting needle marked on each pre-biopsy staging CT scan. Each scan was then reviewed independently by two thoracic radiologists blinded to clinical details and complications; pneumothorax and pulmonary haemorrhage risk estimated with a percentage Visual Analogue Scale. RESULTS In 134 patients, pneumothorax occurred in 24%. The radiologists differed in the estimation of pneumothorax risk in 55% (74 episodes). When pneumothorax risk was estimated <20% by radiologists 1 and 2, 16% and 14% of biopsies resulted in pneumothorax; where risk was estimated at 20-49%, pneumothorax incidence rose to 33% and 31%; where risk was deemed > or =50%, pneumothorax rate was 87% and 100%. Pulmonary haemorrhage occurred in 4%; estimated haemorrhage risk for biopsies complicated by haemorrhage did not differ significantly from where haemorrhage did not occur. CONCLUSION Radiologists differ markedly in the estimation of pneumothorax risk for a patient undergoing co-axial lung biopsy. Identifying individual patients developing pneumothorax was only possible when risk was estimated at > or =50%. Pulmonary haemorrhage was uncommon and difficult to predict accurately.

Experience of long-term use of non-invasive ventilation in motor neuron disease: an interpretative phenomenological analysis

Objective Although non-invasive ventilation (NIV) can promote quality of life in motor neuron disease (MND), previous studies have disregarded the impact of progression of illness. This study explored how patients’ perceptions of NIV treatment evolve over time and how this was reflected in their adherence to NIV. Methods Five patients with MND (male=4, mean age=59 years), from a bigger cohort who were prospectively followed, had multiple post-NIV semistructured interviews, covering more than 12 months, along with ventilator interaction data. The transcribed phenomenological data were analysed using qualitative methodology. Results Three themes emerged: experience of NIV, influence on attitudes and perceived impact of NIV on prognosis. The ventilator interaction data identified regular use of NIV by four participants who each gave positive account of their experience of NIV treatment, and irregular use by one participant who at interview revealed a negative attitude to NIV treatment and in whom MND induced feelings of hopelessness. Conclusions This exploratory study suggests that a positive coping style, adaptation and hope are key factors for psychological well-being and better adherence to NIV. More studies are needed to determine these relationships.

Determinants of accepting non-invasive ventilation treatment in motor neurone disease: a quantitative analysis at point of need.

Objectives: Motor neurone disease (MND) progressively damages the nervous system causing wasting to muscles, including those used for breathing. There is robust evidence that non-invasive ventilation (NIV) relieves respiratory symptoms and improves quality of life in MND. Nevertheless, about a third of those who would benefit from NIV decline the treatment. The purpose of the study was to understand this phenomenon. Design: A cross-sectional quantitative analysis. Methods: Data including age, sex, MND symptomatology, general physical and mental health and psychological measures were collected from 27 patients and their family caregivers at the point of being offered ventilatory support based on physiological markers. Results: Quantitative analyses indicated no difference in patient characteristics or symptomatology between those who tolerated (n = 17) and those who declined (n = 10) NIV treatment. A comparison of family caregivers found no differences in physical or mental health or in caregiving distress, emphasising that this was high in both groups; however, family caregivers supporting NIV treatment were significantly more resilient, less neurotic and less anxious than family caregivers who did not. Regression analyses, forcing MND symptoms to enter the equation first, found caregiver resilience:commitment the strongest predictor of uptake of NIV treatment adding 22% to the 56% explained variance. Conclusion: Patients who tolerated NIV treatment had family caregivers who cope through finding meaning and purpose in their situation. Psychological support and proactive involvement for family caregivers in the management of the illness situation is indicated if acceptance of NIV treatment is to be maximised in MND.

Chronic airflow limitation in a rural Indian population: etiology and relationship to body mass index

Purpose Respiratory conditions remain a source of morbidity globally. As such, this study aimed to explore factors associated with the development of airflow obstruction (AFO) in a rural Indian setting and, using spirometry, study whether underweight is linked to AFO. Methods Patients > 35 years old attending a rural clinic in West Bengal, India, took a structured questionnaire, had their body mass index (BMI) measured, and had spirometry performed by an ancillary health care worker. Results In total, 416 patients completed the study; spirometry was acceptable for analysis of forced expiratory volume in 1 second in 286 cases (69%); 16% were noted to exhibit AFO. Factors associated with AFO were: increasing age (95% confidence interval (CI) 0.004–0.011; P = 0.005), smoking history (95% CI 0.07–0.174; P = 0.006), male gender (95% CI 0.19–0.47; P = 0.012), reduced BMI (95% CI 0.19–0.65; P = 0.02), and occupation (95% CI 0.12–0.84; P = 0.08). The mean BMI in males who currently smoked (n = 60; 19.29 kg/m2; standard deviation [SD] 3.46) was significantly lower than in male never smokers (n = 33; 21.15 kg/m2 SD 3.38; P < 0.001). AFO was observed in 27% of subjects with a BMI <18.5 kg/m2, falling to 13% with a BMI ≥18.5 kg/m2 (P = 0.013). AFO was observed in 11% of housewives, 22% of farm laborers, and 31% of cotton/jute workers (P = 0.035). Conclusion In a rural Indian setting, AFO was related to advancing age, current or previous smoking, male gender, reduced BMI, and occupation. The data also suggest that being under-weight is linked with AFO and that a mechanistic relationship exists between low body weight, smoking tobacco, and development of AFO.

Exercise performance and differences in physiological response to pulmonary rehabilitation in severe chronic obstructive pulmonary disease with hyperinflation

Objective: Pulmonary rehabilitation (PR) improves exercise capacity in most but not all COPD patients. The factors associated with treatment success and the role of chest wall mechanics remain unclear. We investigated the impact of PR on exercise performance in COPD with severe hyperinflation. Methods: We evaluated 22 COPD patients (age, 66 ± 7 years; FEV1 = 37.1 ± 11.8% of predicted) who underwent eight weeks of aerobic exercise and strength training. Before and after PR, each patient also performed a six-minute walk test and an incremental cycle ergometer test. During the latter, we measured chest wall volumes (total and compartmental, by optoelectronic plethysmography) and determined maximal workloads. Results: We observed significant differences between the pre- and post-PR means for six-minute walk distance (305 ± 78 vs. 330 ± 96 m, p < 0.001) and maximal workload (33 ± 21 vs. 39 ± 20 W; p = 0.02). At equivalent workload settings, PR led to lower oxygen consumption, carbon dioxide production (VCO2), and minute ventilation. The inspiratory (operating) rib cage volume decreased significantly after PR. There were 6 patients in whom PR did not increase the maximal workload. After PR, those patients showed no significant decrease in VCO2 during exercise, had higher end-expiratory chest wall volumes with a more rapid shallow breathing pattern, and continued to experience symptomatic leg fatigue. Conclusions: In severe COPD, PR appears to improve oxygen consumption and reduce VCO2, with a commensurate decrease in respiratory drive, changes reflected in the operating chest wall volumes. Patients with severe post-exercise hyperinflation and leg fatigue might be unable to improve their maximal performance despite completing a PR program.

P121 Feasibility of performing valid spirometry in rural India: preliminary results from a population study assessing the prevalence of COPD

Introduction Spirometry remains the cornerstone in the diagnosis of Chronic Obstructive Pulmonary Disease (COPD). Little is known regarding the determinants and prevalence of COPD in rural India. We undertook a population-based study in Howrah District, West Bengal,India at a community-based primary care clinic of a voluntary organisation to test the feasibility of spirometric estimation of the prevalence of COPD. Methods Spirometry was performed on all adults >35 years attending the clinic. Questionnaire data (capturing respiratory symptoms, occupation, tobacco smoking history, indoor stove use) were gathered for each subject. All spirometric data were examined by an independent UK-based clinical scientist. Results Spirometry was performed in 315 patients over 3 months; 18% (58/315) of measurements were deemed good quality as per ERS guidelines; 45% (143/315) had the correct shaped curve; hence 64% (201/315) of all spirometries were deemed adequate for FEV1 analysis. Poor quality traces were noted in 36% (n=114) and hence were excluded from analysis. Of the adequate spirometries (n=201, mean age 51 years (SD 12.1); 39% male), 84 (42%) were normal, 102 (51%) exhibited mild airflow obstruction, 12 (6%) moderate airflow obstruction and 3 (1.5%) severe airflow obstruction according to British guidelines. Difference in FEV1% predicted between never/ex smokers and current smokers was significant (p=0.029). Indoor stove use was ubiquitous in this population and did not correlate with FEV1 percent predicted. Conclusion In a rural Indian setting, valid spirometry can be obtained in two-thirds of adult patients attending a community clinic with 58% of patients in this sample exhibiting at least mild COPD with a history of current smoking being associated with the development of airflow obstruction.

Insights into chronic obstructive pulmonary disease patient attitudes on ventilatory support.

Purpose of review A large proportion of chronic obstructive pulmonary disease (COPD) patients do not actually discuss ventilation and other end-of-life issues in the stable state. Such discussions often occur during the exacerbation itself. There is a paucity of data regarding attitudes of COPD patients toward end-of-life attitudes in general and specifically concerning the area of ventilatory support. Recent findings The majority of COPD patients feel end-of-life discussions are warranted in the stable state. Some studies have shown that increasing age and the presence of depression preclude patients from choosing life-sustaining treatment, whereas physicians were often inaccurate in judging patient preference for cardiopulmonary resuscitation and ventilation as they frequently underestimated patient quality of life. Patient information sheets and other tools may have a role as decision aids in end-of-life discussions. Summary Physicians should consider the discussion of end-of-life issues preferably when patients are stable. Decision aids may prove to be a valuable adjunct in framing treatments such as mechanical ventilation.

The association between pre-hospital antibiotic therapy and subsequent in-hospital mortality in adults presenting with community-acquired pneumonia: an observational study

BackgroundThe majority of patients with community acquired-pneumonia (CAP) are treated in primary care and the mortality in this group is very low. However, a small but significant proportion of patients who begin treatment in the community subsequently require admission due to symptomatic deterioration. This study compared patients who received community antibiotics prior to admission to those who had not, and looked for associations with clinical outcomes.MethodsThis study analysed the Advancing Quality (AQ) Pneumonia database of patients admitted with CAP to 9 acute hospitals in the northwest of England over a 12-month period.ResultsThere were 6348 subjects (mean age 72 [SD 16] years; gender ratio 1:1) admitted with CAP, of whom 17% had been pre-treated with antibiotics. The in-hospital mortality was 18.6% for the pre-treatment group compared to 13.2% in the “antibiotic naïve” group (p < 0.001). On multivariate analysis, age, male gender and antibiotic pre-treatment were predictors of in-hospital mortality along with a history of cerebrovascular accident, congestive cardiac failure, dementia, renal disease and cancer. After adjustment for CURB-65 score, age, co-morbidities and pre-treatment with antibiotics remained as independent risk factors for in-hospital mortality (OR 1.43, 95% CI 1.19–1.71).ConclusionCAP patients admitted to hospital were more likely to die during admission if they had received antibiotics for the same illness pre-admission. Future studies should endeavor to determine the mechanisms underlying this association, such as microbiological factors and the role of comorbidities. Patients hospitalized with CAP despite prior antibiotic treatment in the community require close monitoring.