Few people who end up in the hospital inform their doctors in writing about whether they wish to be revived, an international study has found.

Most critically ill patients undergo cardiopulmonary resuscitation (CPR) by default, unless patients or their families explicitly state not to resuscitate.

When researchers looked at patients at the end of their first day in intensive care, they found nearly 90 per cent had not signed resuscitation orders. Doctors were forced to take heroic measures to try to save lives if a patients' heart stopped.

Older, sicker patients were more likely to sign DNRs

The observational study was done by Deborah Cook, and her colleagues at Hamilton's St. Joseph Hospital and the Canadian Critical Care Trials Group.

"When we don't have documentation of patient preferences ... the assumption is that patients would want to be resuscitated," Cook said.

Over 2,900 adult ICU patients from four countries, Canada, USA, Australia and Sweden, were recruited for the study. Investigators recorded whether, when, and by whom the patients' CPR orders were given.

The study did not include a representative sample from the U.S., Sweden and Australia. The Canadian results were from teaching hospitals and may not reflect what happens in smaller, non-teaching hospitals.

The results were:

• 318 patients, or 11 per cent, had an explicit resuscitation order established within 24 hours of ICU admission – half of those had do-not-resuscitate (DNR) orders.
• Just under half (46 per cent) were made by ICU residents or junior doctors.

Age also mattered. Patients aged 50-64 were three times more likely to have a DNR. Patients aged 65-74 were four times more likely, and those aged over 75 were around nine times more likely to have a DNR than younger patients.

Cause for concern

It was more common for do not resuscitate orders to be given in the first 24 hours of ICU admission, at night and on weekends.

In a commentary accompanying the study, Donald Plough of the University of Texas expressed his concerns about the finding.

"One is left with the discomforting thought that directives were most likely to be established by junior physicians who have little previous knowledge of the patient or their social environment and who are under the pressure that accompanies clinical care of a large group of critically ill patients during off-hours," Plough wrote.

Plough hopes the report will lead to further studies to clarify appropriate strategies for patients, their families and physicians when confronted by deadly illness.

Tough decisions need to be communicated

Cook admits advance directives aren't for everyone but she says the findings suggest doctors and hospitals could do more to find out what their patients want.

"We live in a time where many patients want to take charge of their health and become involved and become active participants in medical decision-making," said Cook.

"And if that's the case, this is an area where people could become engaged and could be communicating their preferences if something horrible happens."

The study appears in Saturday's issue of the medical journal, The Lancet.