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.