Australia’s largest study of survival after ICU admissions provides insight into how patients recover
The largest study into the long-term survival of over 130,000 Victorian patients who have been admitted to a hospital intensive care unit (ICU) in Australia has found an increased risk of early death compared to the general population.
The study, led by Dr Zak Doherty and Associate Professor Rebecca Kippen, from the Monash School of Rural Health, in collaboration with Professor David Pilcher from The Alfred, was published in the journal, PLOS One.
It looked at 130,775 patients who were admitted to intensive care units (ICUs) across Victoria between July 2007 and June 2018. Using data from the Victorian Death Registry, the Australian and New Zealand Intensive Care Society Adult Patient Database and the Victorian Admitted Episodes Dataset, the researchers looked for those who had died within one year of discharge from the ICU.
The study found that, at one year post ICU discharge, 90% of the cohort were still alive compared to 98% of those in the general community. This trend was seen across all demographic subgroups, except for elderly patients who had been admitted into ICU following cardiac surgery.
Importantly, five-year post ICU survival was 73% compared to 89.5% in the general population, and 57.5% at 10 years post ICU compared to 79% in the general population.
The most common reason for admission into ICU was from the operating theatre following emergency department admission. Patients had an average age of 64 years and 59% were male, with 57% living in a major city and 30% in an inner regional town.
Patients in the ICU were most commonly there because of cardiac surgery (15%) and gastrointestinal surgery (13%) with an average stay in ICU of 1.8 days and 8.3 days in hospital, with 70% of patients discharged home from hospital.
A second, and perhaps more important, arm of the study looked at identifying factors that are measurable in hospital that can flag those patients at risk of dying within one year of discharge. Being younger, female and from a higher socio-economic area resulted in a greater chance of survival post ICU.
According to Dr Doherty, the most surprising finding was that elderly patients admitted to ICU after heart surgery had better survival than the general population.
“Such a finding has not been reported previously and demonstrates the quality of ICU care in Australia, something the public has been witness to during the COVID-19 pandemic,” Dr Doherty says.
Associate Professor Kippen said the study gives clues for clinicians advising family members of people admitted to ICU on risks, as well as flagging those who may need extra management post-discharge, such as those from lower socioeconomic areas.
“This new data should be considered by all health care staff when considering the implications of an ICU admission with patients and their families as well as considerations regarding care and discharge,” she said.