Special Populations, Palliative, and End-of-Life Care
Special populations
Older adults have altered pharmacokinetics and more falls, constipation, and delirium; start low, go slow, avoid meperidine, avoid NSAIDs in chronic kidney disease, and watch anticholinergic burden. Children require weight-based dosing; FLACC and NIPS guide assessment; sucrose and comfort positioning help infants; codeine is contraindicated under age 12 and after tonsillectomy. Pregnancy favors acetaminophen; avoid NSAIDs in the third trimester; use the lowest effective opioid for the shortest time. Cognitive impairment calls for PAINAD-type tools, family report, and treating new agitation as possible pain. Renal or hepatic impairment changes dosing of morphine metabolites, gabapentin, and acetaminophen. Sickle cell disease requires rapid, adequate opioids and avoidance of meperidine.
Palliative and end-of-life care
Total pain encompasses physical, psychological, social, and spiritual suffering. Cancer pain generally follows a stepped approach with opioids plus adjuvants, and opioids also relieve dyspnea near the end of life. The principle of double effect permits proportional sedation for refractory suffering; the intent is relief of suffering, not hastening death. Reassess goals of care, screen for delirium, treat constipation and dry mouth, and support the family.
Traps
Do not withhold analgesia from a dying patient out of fear of addiction or of hastening death - untreated pain and dyspnea are the greater harms. Do not apply an acute pain scale to a nonverbal patient, and do not assume a new agitation is anxiety rather than pain or delirium.
Rule of thumb: in serious illness, the question is not whether an opioid is "safe" in the abstract but whether the dose relieves suffering proportionate to the patient's goal.