The guideline approach to chronic obstructive pulmonary disease: how effective?

Clinical practice guidelines are systematically developed to assist health care decisions in specific clinical circumstances. They first arose to improve quality of care by decreasing unexplained practice variation, controlling health care costs, fostering evidence-based decision-making, and accelerating the application of new advances in medical science to everyday practice. Unfortunately, multiple studies demonstrate incomplete and varied effectiveness of clinical practice guidelines in altering clinician behavior and improving patient outcomes. Efforts to enhance guideline effectiveness have focused on improving the methods for guideline development, diffusion, dissemination, and implementation. Despite evidence of limited effectiveness, more than 40 clinical practice guidelines pertaining to chronic obstructive pulmonary disease have been published since 1985. The present article reviews those guidelines, evidence for their effectiveness, and approaches to improve their implementation.     

How do patients with exacerbated chronic obstructive pulmonary disease experience care in the intensive care unit?

The aim was to gain insight into how patients with advanced chronic obstructive pulmonary disease (COPD) experience care in the acute phase. The study has a qualitative design with a phenomenological approach. The empirics consist of qualitative in‐depth interviews with ten patients admitted to the intensive care units in two Norwegian hospitals. The interviews were carried out from November 2009 to June 2011. The data have been analysed through meaning condensation, in accordance with Amadeo Giorgi's four‐step method. Kari Martinsen's phenomenological philosophy of nursing has inspired the study. An essential structure of the patients' experiences of care in the intensive care unit by acute COPD‐exacerbation may be described as: Feelings of being trapped in a life‐threatening situation in which the care system assumes control over their lives. This experience is conditioned not only by the medical treatment, but also by the entire interaction with the caregivers. The essence of the phenomenon is presented through three themes which describe the patient's lived experience: preserving the breath of life, vulnerable interactions and opportunities for better health. Acute COPD‐exacerbation is a traumatic experience and the patients become particularly vulnerable when they depend on others for breathing support. The phenomenological analysis shows that the patients experience good care during breath of life preservation when the care is performed in a way that gives patients more insight into their illness and gives new opportunities for the future.     

Neurally adjusted non-invasive ventilation in patients with chronic obstructive pulmonary disease: does patient–ventilator synchrony matter?

Patient–ventilator interaction represents an important clinical challenge during non-invasive ventilation (NIV). Doorduin and colleagues’ study shows that non-invasive neurally adjusted ventilatory assist (NAVA) improves patient–ventilator interaction compared with pressure support ventilation in patients with chronic obstructive pulmonary disease. There is no doubt nowadays that NAVA is the most effective mode of improving the synchrony between patient and machine, but the key question for the clinicians is whether or not this will make a difference to the patient’s outcome. The results of the study still do not clarify this issue because of the very low clinically important dyssynchrony, like wasted efforts, in the population studied. Air leaks play an important role in determining patient–ventilator interaction and therefore NIV success or failure. Apart from the use of a dedicated NIV ventilator or specific modes of ventilation like NAVA, the clinicians should be aware that the choice of interface, the humidification system and the appropriate sedation are key factors in improving patient–ventilator synchrony.A lot of emphasis has been placed recently on the problem of patient–ventilator interaction during non-invasive ventilation (NIV). This issue is particularly important in patients with chronic obstructive pulmonary disease during an episode of acute hypercapnic respiratory failure.In their elegant study, Doorduin and colleagues show that the use of non-invasive neurally adjusted ventilatory assist (NAVA) improved patient–ventilator synchrony compared with pressure support ventilation (PSV), delivered either by a dedicated NIV platform or by an ICU ventilator with dedicated software [1]. Indeed, they demonstrated that automated analysis of ventilator pressure and diaphragm electrical activity waveforms allowed an objective detection of patient–ventilator interaction.This study largely confirmed the results already described in other investigations performed in heterogeneous groups of critically ill patients [2,3]. There is no doubt nowadays that NAVA is the most effective mode of improving the synchrony between patient and machine, but the key question for the clinician is whether or not this will make a difference to the patient’s outcome.In other words, does patient–ventilator synchrony matter? In invasively ventilated patients, a high incidence of asynchrony is associated with a prolonged duration of mechanical ventilation and a higher rate of tracheotomy during assisted mechanical ventilation [4]. This association was mainly due to a nonappropriate setting of the ventilator parameters (that is, a high inspiratory pressure or a less sensitive trigger), rather than the patient’s clinical severity or ventilatory modes [5]. A higher discomfort in patients receiving NIV for acute and even chronic respiratory failure was reported, but apparently did not influence gas exchange or any other clinical parameter [6]. Comfort is a main goal to achieve during NIV since it may determine the tolerance of the patient, which is still one of the main causes of NIV failure and therefore of intubation [7]. NIV is a semi-open system and air leaks around the mask are very likely to occur, particularly in the first few hours of ventilation when the patient needs to adapt to this non-natural breathing. Air leaks are the major cause of poor synchrony during NIV [6] and therefore dedicated NIV platforms and ICU ventilators using a specific module have been developed to minimize this problem. In vivo and bench assessment showed that these ventilators, particularly the former, are able to almost avoid the occurrence of mismatching [8]. In contrast, the study by Doorduin and colleagues showed a considerable amount of dyssynchrony especially using the NIV platform during PSV [1].The authors have used a sophisticated automatic algorithm to define acceptable synchrony (that is, an error between electrical activity of the diaphragm and airway pressure above 20%) [1].The threshold of this definition was arbitrarily chosen. It was not clear what could be the clinical impact of this discrepancy, if not that this threshold value is associated with a higher occurrence of wasted efforts. Surprisingly the number of these events, the only ones associated with the worst outcomes in intubated patients [4], was extremely low in the three different trials. On one hand this may be explained by the fact that PSV and NAVA are, besides small differences, equally effective in avoiding major asynchrony events, but on the other that they are related by the nature of Doorduin and colleagues’ study [1]. As a matter of fact the patients enrolled in the study were recovering from an episode of acute respiratory failure with a normal pH, and were therefore ventilated with a low inspiratory pressure (mean 7 cmH₂O) that is very unlikely to induce the phenomenon of wasted efforts.In our view the most striking difference highlighted by the study was the huge discrepancy in the time to trigger the ventilator between NAVA and PSV, which has usually been explained by the fact that the ventilator with NAVA is triggered directly by electrical activity of the diaphragm, regardless of the presence of intrinsic positive end-expiratory pressure (PEEP). The mean level of set PEEP during PSV was around 6 cmH₂O, and therefore was close enough to balance the level of intrinsic PEEP recorded during an acute exacerbation of chronic obstructive pulmonary disease patients [9]. The presence of air leaks was the major driver of the delay rather than the presence of intrinsic PEEP.When the respiratory drive is elevated, such as in the case of acute respiratory failure, the scenario may be different. A mathematical model has shown that, in the presence of an inspiratory leak proximal to the airway, opening can be accompanied by marked variations in duration of the inspiratory phase and in autoPEEP [10], and this may be a rationale for using NAVA as a preferred method of NIV.Despite the fact that the clinical impact of a poor patient–ventilator interaction is still not clear, the role of the mode of ventilation still needs to be elucidated, while the presence of air leaks should be always minimized.Other than using a ventilator specifically compensating for leaks, the clinicians should be aware that the choice of the interface, the humidification system and, last but not least, the appropriate sedation have been shown to improve the patient’s tolerance of NIV [11].     

Chronic obstructive pulmonary disease patients with invasive pulmonary aspergillosis: benefits of intensive care?

OBJECTIVES: Invasive pulmonary aspergillosis (IPA) is increasingly recognized as a cause of acute respiratory failure in patients with chronic obstructive pulmonary disease (COPD) treated with corticosteroids. For these patients admission in intensive care unit (ICU) is often required for life-support and mechanical ventilation. Whether this approach improves outcome is unknown. DESIGN AND SETTING: Retrospective study in a university hospital intensive care unit. PATIENTS: Between November 1993 and December 1997, 23 COPD patients were admitted in our ICU and received antifungal agents for possible IPA. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The clinical features and the outcome were reviewed. Diagnosis of IPA was classified as confirmed (positive lung tissue biopsy and/or autopsy) or probable (repeated isolation of Aspergillus from the airways with consistent clinical and radiological findings). Among the 23 patients treated for Aspergillus, 16 fulfilling these criteria for IPA were studied. Steroids had been administered at home to all patients but one and were increased during hospitalization in all. Twelve patients suffered a worsening of their bronchospasm precipitating acute respiratory failure. During ICU stay all patients required mechanical ventilation for acute respiratory failure. Although amphotericin B deoxycholate was started when IPA was suspected (0.5-1.5 mg/kg per day), all patients died in septic shock (n = 5) or in multiple-organ failure. CONCLUSIONS: The poor prognosis of intubated COPD patients with IPA, in spite of antifungal treatment suggests that further studies are required to define the limits and indications for ICU management of these patients.     

Heliox and noninvasive positive-pressure ventilation: a role for heliox in exacerbations of chronic obstructive pulmonary disease?

Evidence-based respiratory therapy for exacerbations of chronic obstructive pulmonary disease (COPD) includes oxygen, inhaled bronchodilators, and noninvasive positive-pressure ventilation. Examining the physics of gas flow, a case can be made either for or against the use of helium-oxygen mixture (heliox) in the care of patients with COPD. The evidence for the use of heliox in patients with COPD exacerbation is not strong at present. Most of the peer-reviewed literature consists of case reports, case series, and physiologic studies in small samples of carefully selected patients. Some patients with COPD exacerbation have a favorable physiologic response to heliox therapy, but predicting who will be a responder is difficult. Moreover, the use of heliox is hampered by the lack of widespread availability of an approved heliox delivery system. Appropriately designed randomized controlled trials with patient-important outcomes, such as avoidance of intubation, decreased intensive-care-unit and hospital days, and decreased cost of therapy, are sorely needed to establish the role of heliox in patients with COPD exacerbation, including those receiving noninvasive positive-pressure ventilation. Lacking such evidence, the use of heliox in patients with COPD exacerbation cannot be considered standard therapy.     

How sustainable is strength training in chronic obstructive pulmonary disease?

Objectives

To examine whether the benefits from strength training are sustained after an initial training period in patients with chronic obstructive pulmonary disease (COPD).

Data sources

MEDLINE (1966 to May 2008), CENTRAL (1948 to May 2008) and PEDro (1929 to May 2008).

Review methods

Criteria for inclusion in this review were that study participants had COPD and undertook an intervention that included strength training. A period of follow-up (≥12 weeks) after strength training and a measure of muscle strength taken at this time were required. All experimental study designs were accepted, and the publication language had to be English. Reviews were excluded. The PEDro scale was used to assess the methodological quality of studies.

Results

Only three eligible studies were identified (PEDro scores ranged from 5 to 7). Two studies found that the benefits from strength training were still evidental at 12 weeks and 12 months after an initial 12-week and 6-month training period, respectively. The other study found no difference between the control and training groups 12 weeks after a 12-week training intervention. Only one study discussed continuation of strength training during the follow-up period. The results of these studies could not be pooled for meta-analysis, as the study interventions and assessments were heterogeneous.

Conclusion

Despite an extensive search of the literature, only three articles were identified. Therefore, the long-term effects of strength training remain unknown. Further trials examining the sustainability of strength training with homogeneous populations, training programmes and assessments are warranted. This would enable the pooling of results for meta-analysis, and provide clearer recommendations to pulmonary rehabilitation practitioners.     

What is the danger of long-term application of beta blockers in patients with ischemic heart disease and concomitant chronic obstructive pulmonary disease?

AIM: To show specific features of respiratory disoders in patients with ischemic heart disease (IHD) and chronic obstructive pulmonary disease (COPD) taking atenolol for a long time. MATERIAL AND METHODS: A long-term study of external respiration function was made in 287 patients with IHD and COPD treated with berodual and atenolol (group 1) vs 74 matched patients taking berodual only. RESULTS: Atenolol treated patients demonstrated more pronounced respiratory disorders. Small respiratory tracts were involved earlier with appearance of expiratory peripheral collapse and early expiratory closure of the respiratory tracts. Diffuse ability of the pulmonary tissue deteriorated. Conclusion. Atenolol has a negative effect on the respiratory system, so it is necessary to control external respiratory function in the course of treatment.     

Family care in chronic obstructive pulmonary disease: what happens when the carer is a man?

Chronic obstructive pulmonary disease (COPD) is a major cause of disability, morbidity and mortality in old age, representing a significant burden for family carers. However, knowledge regarding the specific issues faced by men in the COPD caregiving role is nonexistent. This study explored the experience of husbands and sons providing care to a family member with moderate‐to‐severe COPD. A cross‐sectional qualitative study using in‐depth, semi‐structured individual interviews was conducted with twelve men carers: seven husbands with a mean age of 70.9 ± 8.8 years and five sons with a mean age of 43.4 ± 10.5 years. The interviews were analysed for recurrent themes using thematic analysis. Main findings suggest that men are committed and dedicated carers; however, differences between husbands and sons related to ‘meaning’, ‘challenges and constraints’, ‘fears and concerns about the future’, ‘needs’ and ‘positive aspects’ have emerged. These differences reflect relationship and generational differences and are of relevance when planning adequate community support interventions.