A 72-year-old man under the care of the inpatient palliative care service is experiencing shortness of breath. His past medical history is significant for worsening end-stage chronic obstructive pulmonary disease (COPD), and he has a do-not-resuscitate/do-not-intubate order in place. Venous thromboembolism and pleural effusion have been ruled out. The patient has been optimized on supplemental oxygen and his other respiratory medications. Which of the following medications is MOST likely to provide relief for this patient’s dyspnea?
- (A) Naloxone
- (B) Midazolam
- (C) Morphine
Dyspnea is defined by the American Thoracic Society as “a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity.” Dyspnea can cause significant suffering and typically worsens throughout a patient’s disease trajectory near the end of life. The management of symptoms of dyspnea is an important aspect of end-of-life care, as these symptoms can be very distressing for the patient and their loved ones. If there is a reversible cause for the dyspnea that can be treated, this should be undertaken (e.g., thoracentesis for an effusion). In the patient who is otherwise optimized but still experiencing dyspnea, symptom management is an important aspect of care. This may occur in COPD, advanced heart failure, and certain cancers near the end of life. Many patients will experience refractory dyspnea that cannot be corrected despite appropriate treatment. For these patients, symptom management is the best therapy.
The patient in the clinical scenario has end-stage COPD and is otherwise optimized on oxygen and medications. No obvious reversible causes are evident. Therefore, symptom management of his dyspnea should be considered. Low-dose oral or parenteral opioids are the mainstay therapy for treatment of refractory dyspnea in this patient population, regardless of the cause. Effective relief of dyspnea can be achieved with total daily morphine doses as low as 10 mg. Initial doses of immediate-release morphine formulations (2.5-5 mg every 4-6 hours) have been suggested to establish efficacy and tolerability. Once a stable dose has been established, switching to a sustained-release formulation may increase patient adherence and improve symptom control. Anticipated adverse effects of opioids (e.g., sedation, nausea, constipation) are usually easily managed. Low doses of opioids are not typically associated with an increased risk of respiratory depression, hospital admission, or death.
The role of benzodiazepines such as midazolam in the management of dyspnea for this patient population remains unclear. The rationale supporting the use of benzodiazepines in these scenarios is to treat the anxiety commonly associated with dyspnea. However, meta-analyses thus far lack sufficient evidence to recommend benzodiazepines for this purpose.
Naloxone does not play a role in symptom management of dyspnea in a scenario such as this but may play a role in scenarios where respiratory suppression is due to opioid administration.
Answer: C