Measurement and treatment of dyspnoea

Dyspnea and Dyspnea-Associated Anxiety in the ICU Patient Population: A Narrative Review for CL Psychiatrists

BACKGROUND

Consultation-liaison psychiatrists frequently address dyspnea in intensive care unit (ICU) patients. Dyspnea is common in this patient population, but is frequently misunderstood and underappreciated in noncommunicative ICU patients.

OBJECTIVE

This paper provides an updated review on dyspnea specifically in the ICU population, including its pathophysiology and management, pharmacological and nonpharmacological, aimed at consultation-liaison psychiatrists consulting in ICU.

METHODS

A literature review was conducted with PubMed, querying published articles for topics associated with dyspnea and dyspnea-associated anxiety in ICU patient populations. When literature in ICU populations was limited, information was deduced from dyspnea and anxiety management from non-ICU populations. Articles discussing the definition of dyspnea, mechanistic pathways, screening tools, and pharmacologic and nonpharmacologic management were included.

RESULTS

A reference guide was created to help consultation-liaison psychiatrists and intensivists in the screening and treatment of dyspnea and dyspnea-associated anxiety in critically ill patients.

CONCLUSIONS

Dyspnea is frequently associated with anxiety, prolonged days on mechanical ventilation, and worse quality of life after discharge. It can also increase the risk of posttraumatic stress disorder post-ICU discharge. However, it is not routinely screened for, identified, or addressed in the ICU. This manuscript provides an updated review on dyspnea and dyspnea-associated anxietyin the ICU population, including its pathophysiology and management, and offers a useful reference for consultation-liaison psychiatrists to provide treatment recommendations.

Fixed-intensity exercise tests to measure exertional dyspnoea in chronic heart and lung populations: a systematic review

INTRODUCTION

Exertional dyspnoea is the primary diagnostic symptom for chronic cardiopulmonary disease populations. Whilst a number of exercise tests are used, there remains no gold standard clinical measure of exertional dyspnoea. The aim of this review was to comprehensively describe and evaluate all types of fixed-intensity exercise tests used to assess exertional dyspnoea in chronic cardiopulmonary populations and, where possible, report the reliability and responsiveness of the tests.

METHODS

A systematic search of five electronic databases identified papers that examined 1) fixed-intensity exercise tests and measured exertional dyspnoea, 2) chronic cardiopulmonary populations, 3) exertional dyspnoea reported at isotime or upon completion of fixed-duration exercise tests, and 4) published in English.

RESULTS

Searches identified 8785 papers. 123 papers were included, covering exercise tests using a variety of fixed-intensity protocols. Three modes were identified, as follows: 1) cycling (n=87), 2) walking (n=31) and 3) other (step test (n=8) and arm exercise (n=2)). Most studies (98%) were performed on chronic respiratory disease patients. Nearly all studies (88%) used an incremental exercise test. 34% of studies used a fixed duration for the exercise test, with the remaining 66% using an exhaustion protocol recording exertional dyspnoea at isotime. Exertional dyspnoea was measured using the Borg scale (89%). 7% of studies reported reliability. Most studies (72%) examined the change in exertional dyspnoea in response to different interventions.

CONCLUSION

Considerable methodological variety of fixed-intensity exercise tests exists to assess exertional dyspnoea and most test protocols require incremental exercise tests. There does not appear to be a simple, universal test for measuring exertional dyspnoea in the clinical setting.

Assessment of dyspnoea in the emergency department by numeric and visual scales: A pilot study

OBJECTIVE(S)

Dyspnoea is a common and often debilitating symptom that affects up to 50% of patients admitted to acute tertiary care hospitals. The primary purpose of this study was to compare the numeric rating scale (NRS) and the visual analogue scale (VAS) for dyspnoea evaluation in the ED setting.

STUDY DESIGN AND PATIENTS

This was a cohort study of patients admitted to the ED in a university hospital, with dyspnoea as the chief complaint.

METHODS

The agreement of the two dyspnoea scales was assessed using the intraclass correlation coefficient (ICC).

RESULTS

One hundred and seventeen patients were included in this analysis. The median age for the whole study population was 67 years and 42% of patients were male. The aetiology of dyspnoea was acute heart failure (AHF) in 35% of patients. There was good agreement between the two scores (ICC=0.795; 95% CI=0.717-0.853; P<0.001).

CONCLUSIONS

This pilot study demonstrated that numerical rating and visual analogue scales agree well when assessing the severity of dyspnoea in the ED. Further studies with larger cohorts of patients are needed to confirm these preliminary results.

Validation of a verbal dyspnoea rating scale in the emergency department

OBJECTIVE

Use of a verbal dyspnoea rating scale in the emergency department (ED) has many potential benefits, providing information to clinicians otherwise not afforded by objective parameters. In the present study, we aimed to investigate the validity of a verbal dyspnoea rating scale, previously validated in the setting of cardiac stress tests, among patients presenting to the ED with acute shortness of breath (SOB).

METHODS

This was a prospective observational study conducted at an inner-urban adult tertiary hospital. A convenience sample of patients presenting with SOB to the ED had objective data collected at triage and 30 min later, including respiratory rate (RR), oxygen saturation (S(a)O(2)), heart rate (HR) and systolic blood pressure (SPB). These were correlated with the participants' subjective response to the question: 'On a scale from 0 to 10, how bad is your SOB, with zero being no SOB and 10 the worst SOB you could ever imagine?' Spearman correlations were then calculated between objective and subjective breathlessness measures.

RESULTS

For 253 breathless ED patients (mean age 60.6 years, 126 male), verbal dyspnoea scores at triage correlated with RR (r = 0.77, P < 0.001), S(a)O(2) (r =-0.43, P < 0.001), HR (r = 0.35, P < 0.001) and SPB (r = 0.19, P < 0.05). Thirty minutes later, correlations remained significant for RR (r = 0.74, P < 0.001), S(a)O(2) (r =-0.39, P < 0.001) and HR (r = 0.40, P < 0.001).

CONCLUSION

A verbal numerical SOB rating scale is a valid measure of breathlessness in the ED, and might therefore provide useful insight into a symptom that is otherwise unmeasurable.

The clinical management in extremely severe COPD

Chronic obstructive pulmonary disease (COPD) affects 6% of the general population and is the fourth-leading cause of death in the United States with severe and very severe disease accounting for 15% and 3% of physician diagnoses of COPD. Guidelines make few recommendations regarding providing the provision of care for the most severe stages of disease, namely Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages III and IV with chronic respiratory failure. The effectiveness of inhaled drug therapy in very severe patients has not been assessed yet. Health care systems in many countries include public funding of long-term oxygen therapy for eligible candidates. Currently, there is little evidence for the use of mechanical ventilatory support in the routine management of hypercapnic patients. Pulmonary rehabilitation should be considered as a significant component of therapy, even in the most severe patients. Although Lung Volume Reduction Surgery has been shown to improve mortality, exercise capacity, and quality of life in selected patients, this modality is associated with significant morbidity and an early mortality rate in the most severe patients. Despite significant progress over the past 25 years, both short- and long-term outcomes remain significantly inferior for lung transplantation relative to other "solid" organ recipients. Nutritional assessment and management is an important therapeutic option in patients with chronic respiratory diseases. Morphine may significantly reduce dyspnoea and does not significantly accelerate death. No consistent improvement in dyspnoea over placebo has been shown with anxiolytics. Supplemental oxygen during exercise reduces exertional breathlessness and improves exercise tolerance of the hypoxaemic patient. Non-invasive ventilation has been used as a palliative treatment to reduce dyspnoea. Hypoxaemic COPD patients, on long-term oxygen therapy, may show reduced health-related quality of life, cognitive function, and depression. Only a small proportion of patients with severe COPD discuss end-of-life issues with their physicians.

Is there any treatment other than drugs to alleviate dyspnea in COPD patients?

Patients with chronic obstructive pulmonary disease (COPD) are often limited in their activities by breathlessness. In these patients, exercise training may result in significant improvements in dyspnea, exercise tolerance, and health related quality of life (HRQoL). Further possibilities are to reduce ventilatory demand by decreasing the central respiratory drive or to lessen the perceived breathing effort by increasing respiratory muscle strength through specific respiratory muscle training. Upper limb training may also improve exercise capacity and symptoms in these patients through the modulation of dynamic hyperinflation. Ventilatory assistance during exercise reduces dyspnea and work of breathing and enhances exercise tolerance, although further studies should be required to define their applicability in the routine pulmonary rehabilitation programs. Lung volume resection surgery and lung transplantation in selected patients may control symptoms and improve HRQoL.