Acute episodic
breathlessness in patients receiving
palliative care is a distressing symptom with little evidence-base to inform management. This pilot, double-blind, controlled, crossover study compared the effects of nebulized
hydromorphone, systemic
hydromorphone and nebulized saline for the relief of episodic
breathlessness in advanced
cancer patients. On three occasions of acute
breathlessness, patients randomly received either nebulized
hydromorphone, a systemic breakthrough dose of
hydromorphone or nebulized saline together with a blinding agent.
Breathlessness was scored before and 10, 20, 30, and 60 minutes post-treatment completion using a 100 mm visual analog scale. Twenty patients completed the trial. Ratings did not differ significantly across pretest treatments. Change in ratings from pretest to 10 minutes after completion of nebulization (about 20 minutes after administration of systemic
hydromorphone) indicated that each of the treatments resulted in statistically significant improvements in
breathlessness, with no significant differences between treatments. Over time,
breathlessness decreased significantly for all treatments, with no significant differences between treatments. Only nebulized
hydromorphone produced a rapid improvement in
breathlessness that reached a magnitude considered to be clinically important. Interpretation of these results is considered in relation to our definition of clinical significance, the dose of
hydromorphone used and the possibility of a placebo effect. This study can serve to inform the design of future trials to investigate the management of incident
breathlessness.