A few months ago three doctors stated flatly in JAMA that the American system of advance care planning (ACP) is broken. Logic was on its side: what could be more sensible than having serious discussions well in advance about what should be done in end-of-life care. But experience has showed that the reality is different. “ACP does not improve end-of-life care, nor does its documentation serve as a reliable and valid quality indicator of an end-of-life discussion.”

Why? Daniela J. Lamas, a pulmonary and critical-care physician at Brigham and Women’s Hospital in Boston, explains in an op-ed in the New York Times.

“Humans have an amazing capacity to adapt to illness or disease. From the vantage point of youth or good health, it is easy for people to say that they would rather die than live with significant limitations, pain or dependence on others.

“But people evolve in ways they cannot expect. This is why some survivors of catastrophic accidents, such as spinal cord injuries leading to complete paralysis, nevertheless come to rate their quality of life as good — even if they never would have imagined being able to do so before the accident. As a result, what people are willing to go through to extend their life might change depending on the context. Advance directives written at one point in time about hypothetical scenarios cannot capture what someone actually wants at every point in the future.”

In her article she describes a patient who declared very clearly in writing that she never wanted to be intubated if she were in critical care. But when she found find herself in that situation several years later, she changed her mind. Spending more time with her family became more important than the pain and dependency involved with intubation.

Dr Lamas says that doctors should focus more on the wishes of a patient when they are seriously ill, not when they are in ruddy good health. And the conversation should centre “less on their thoughts about specific medical interventions and more on their understanding of their prognosis, what is important to them and what gives their lives meaning.”