The ethics of end-life sedation and hydration
The Straits Times
By Andy Ho
SINGAPORE - The National University of Singapore medical school just launched an online casebook about ethical dilemmas that doctors face, including end-of-life issues, which have been on my mind a lot lately.
My mother passed away at 81 less than two weeks ago from end-stage adenocarcinoma of the lung.
Diagnosed 14 months earlier, she was virtually symptom-free for the first 13 months. So she did quite well considering also that the median survival time for such cases is about 8 months.
Locally, lung cancer is the third most common malignancy in women. And the adenocarcinoma variety is the most common form of lung cancer in women, often non-smokers like my mother.
Because the adenocarcinoma often begins in the outer parts of the lungs, symptoms like cough, shortness of breath and blood in the sputum are not common: my mother never had them.
She stayed active and independent until the final month of her life when the cancer started producing the antidiuretic hormone (ADH). In health, it is the pituitary gland in the brain that produces ADH, which normally maintains the delicate balance of water and salt in the body.
When a cancer itself starts producing ADH - this is called the syndrome of inappropriate antidiuretic hormone (SIADH) production - it upsets the body's delicate balance of water and salt.
In SIADH, the kidneys stop producing urine, so the body retains too much water and does not have enough salt. At this point, the patient becomes weak, confused, delirious and may fall into a coma.
Because the body retains water excessively in SIADH, the patient is not allowed liquids. At this point, I asked if my very delirious and distressed mother could be sedated continuously until death.
This is called continuous deep sedation (CDS), during which fluids are concurrently discontinued, even if there is no SIADH.
My mother had, on several previous occasions, expressed her wish to many of us separately that she wanted to suffer as little as possible. Hence my request for CDS, to render her unconscious until she died.