This study by Flaatten et al., looked at thirty day survival for very elderly patients admitted it ICU and was published in ICM just before Christmas. Survival to 30 days decreased for all groups down the scale form not frail to vulnerable, to frail. Furthermore the impact of CFS on outcome was more than that of either age or SOFA score.
It is worth remembering that this study only collected data on those admitted (not those who remained on the ward) and interestingly some 23% of patients didn’t receive any ITU specific treatment.
Do you routinely use a frailty scale as part of your assessment of ICU candidates for admission? This study would suggest CFS could reliably predict a subgroup modem likely to die in 30 days.