Introduction and rationale Exertional wheeze and dyspnoea are most frequently attributed to exercise induced bronchoconstriction (EIB), yet may arise secondarily to a temporary closure of the larynx. This condition, termed Exercise induced laryngeal obstruction (EILO), is best characterised by the gold standard technique of direct and continuous laryngoscopy during exercise (CLE). To date most descriptions of the utility of CLE are in young highly athletic populations.
Objectives Assessment of the safety, utility and application of CLE in subjects with unexplained and/or disproportionate exertional dyspnoea in a general respiratory population (i.e. not confined to athletes).
Methods and measurements Patients referred for CLE with unexplained breathlessness and other respiratory diagnosis including treatment refractory asthma and COPD were identified. Thereafter clinical and physiological assessments were reviewed.
Results In total 83 referrals (October 2012–February 2014) for CLE studies were analysed. The overall median (range) age was 43 (17–71) years. The majority of subjects were female (n = 56). Only a total of 4 (5%) subjects were athletes. We made a diagnosis of EILO in 30 (36%) of subjects studied. Prior to CLE 32 (39%) had been given a diagnosis of EIB, and of these we identified 17 (53%) actually had a diagnosis of EILO. Only one minor complication (pre-syncopal episode) was encountered during the procedure.
Conclusion CLE is a safe effective method for the assessment of disproportionate exercise induced dyspnoea. It is a sensitive diagnostic tool and should not be reserved for use in a highly athletic population. It appears to be particularly useful in patients diagnosed with EIB who are not responding to treatment. Therapeutic intervention in the form of physiotherapy once the diagnosis is made offers the potential for symptomatic improvement and the withdrawal of unneeded pharmacological agents.