Safety of opioids and benzodiazepines in patients with breathlessness and respiratory failure associated with Chronic Obstructive Pulmonary Disease

摘要

Dyspnea, defined by the 1999 ATS nsity”1, is a highly distressful symptom,experienced by 94% of severe chronic lung disease and 78% of advancedlung cancer patients during the final year of their life2. Furthermore, painand anxiety are cardinal symptoms highly prevalent in both diseases3.Provided that treatment of the underlying condition has already beenoptimised, benzodiazepines and opioids are pharmacological optionsconsidered by physicians for the management of refractory dyspnea. Whilethere is not enough evidence in the literature supporting a beneficial effectof benzodiazepines on breathlessness4, oral and parenteral opioids havebeen shown to have a statistically significant effect in managing refractorydyspnea5,6. On the other hand, not enough data support the use ofnebulized opioids5,7. The possible mechanisms by which opioid seem toalleviate dyspnea include reductions in the central perception of dyspnea(similar to the central perception of pain), dyspnea-associated anxiety, totalventilation, oxygen consumption, sensitivity to hypoxemia and hypercapnia,as well as an improvement in cardiovascular function and an increase inventilator efficacy with exercise5,8.