Patel Ami V, Ackermann Richard J
Mercer University School of Medicine Department of Family Medicine, 1550 College Street, Macon, GA 31207-0001.
FP Essent. 2016 Aug;447:32-41.
Competence is determined by a court of law, whereas physicians determine medical decision-making capacity (DMC). When patients lack DMC, a surrogate should be identified to make decisions. Ideally, patients will have created a durable power of attorney for health care. If a patient did not do this, state statutes specify which individuals can serve as surrogates; a current spouse typically is the first choice. Ideally, surrogates should use substituted judgment in making decisions. If this is not possible because the patient never shared end-of-life wishes with the surrogate, the surrogate can make decisions that, in the surrogate's opinion, are in the patient's best interests or that a reasonable individual would make. When no surrogate can be identified and a patient has no written advance directive, hospital ethics committees can assist with decisions, or, for some patients, a court will need to appoint a guardian. When there is a surrogate, difficulties can arise when family members disagree with the surrogate's decisions or when surrogates request treatments that, in the physician's opinion, would be futile or nonbeneficial. Hospital ethics committees may be able to assist in these situations, but appropriately conducted family meetings often resolve such difficulties.
行为能力由法院判定，而医生则负责判定医疗决策能力（DMC）。当患者缺乏医疗决策能力时，应指定一位代理人来做出决策。理想情况下，患者应已设立医疗保健持久授权书。如果患者未这样做，州法规会规定哪些人可以担任代理人；现任配偶通常是首选。理想情况下，代理人应采用替代判断来做出决策。如果由于患者从未与代理人分享过临终愿望而无法做到这一点，代理人可以做出其认为符合患者最佳利益的决策，或者做出一个理性的人会做出的决策。当无法确定代理人且患者没有书面预先指示时，医院伦理委员会可以协助做出决策，或者对于某些患者，法院需要指定一名监护人。当有代理人时，如果家庭成员不同意代理人的决策，或者代理人要求进行医生认为无效或无益处的治疗，可能会出现困难。医院伦理委员会可能能够在这些情况下提供帮助，但进行得当的家庭会议通常可以解决此类困难。
