In our August 17, 2010 Patient Safety Tip of the Week “” we made a case that we need to change the focus of any preoperative evaluation away from the traditional “organ” approach (such as assessing cardiac risk) and instead focus on the more global physiological reserve of patients. That would mean focusing on some of the multiple factors that might give rise to delirium and focusing on a variety of factors that collectively define “frailty”.
In our June 2010 What’s New in the Patient Safety World colum “The Frailty Index and Surgical Outcomes” we noted a study (Makary et al 2010) demonstrating use of the frailty index greatly improved the ability to predict post-surgical outcomes much better than existing methods.
In 2009 Robinson and colleagues (Robinson 2009) looked at outcomes in (mostly male) patients age 65 and older who were undergoing major elective surgical procedures in the VA medical system and correlated them with measures of frailty, disability, and comorbidity. Using a group of markers that were easy to use in a surgeon’s office setting they were able to predict 6-month postoperative mortality and post-discharge institutionalization. They did not use one of the existing frailty indices but rather constructed a tool based on the following variables: age, cognitive impairment, chronic malnutrition, falls, depression, anemia and supplemented these with the Katz disability scale and the Charlson comorbity index. Any functional dependence was the biggest sole risk predictor and four or more markers on any one patient predicted 6-month mortality with a sensitivity of 81% and specificity of 86%.
That group has now expanded their study to a total of 223 subjects (Robinson 2011) and focused on discharge to an institutional setting. The burden of comorbidity was assessed using the Charlson index, the ASA score, the total number of medications taken, and anemia. Function was measured by the Katz ADL score and a timed up-and-go test. Nutrition was assessed by BMI, albumin level, and weight loss. Cognitive function was assessed by the Mini-Cog test and the Two-Question Depression Screen. And they added a measure of “geriatric syndromes” (eg. falls) and “extrinsic frailty” (eg. social isolation). Overall, 30% of patients were discharged to institutional settings and another 17% needed home care. The 3 variables most predictive of institutionalization were a timed up-and-go >15 seconds, Charlson score 3 or greater, and hematocrit <35%. Three or more frailty characteristics had a sensitivity of 82% and specificity of 84% for predicting institutionalization. Interestingly, age itself was not a predictor but rather the measures of frailty, function, and comorbidities were most important.
The study we previously mentioned (Makary et al 2010) in our June 2010 What’s New in the Patient Safety World column “The Frailty Index and Surgical Outcomes” demonstrated that use of the frailty index greatly improves the ability to predict post-surgical outcomes (post-op complications, LOS, and discharge to an SNF or assisted living setting) much better than existing methods. They used the frailty index which assigns a score of 0 or 1 for each of five domains: weight loss, weakness, low physical activity, exhaustion, and slow walking speed. It takes about 10 minutes to administer the frailty index. Weakness is measured with a hand ergometer. Walking speed is measured by having the patient walk 15 feet and timing them. Weight loss is 10 or more pounds lost unintentionally in the past year. And the other 2 domains are assessed by asking simple questions. Patients scoring 4-5 are classified as being frail, those scoring 2-3 as intermediately frail. The frailty index has been validated and been predictive of outcomes in medical patients. However, the research group at Johns Hopkins assessed the ability of this index done preoperatively to predict certain post-surgical outcomes.
The frailty index turned out to be very good in its ability to predict surgical outcomes. For instance, the odds ratio for frail patients for postoperative complications after major surgery was 2.54, for length of stay 1.69, and for discharge to a skilled nursing facility or assisted living facility 20.48. Odds ratios for those with intermediate frailty were somewhat lower but still predictive of all the above. And the frailty index was better than other tools used to predict outcomes (ASA score, Lee’s revised cardiac risk index, and the Eagle score). Adding the frailty index to any of those tools significantly improved the predictability of outcomes.
It will be very interesting to see how the frailty index fares in other settings (eg. community hospitals, etc.). This could be an extremely helpful tool in helping to avoid some of the pain and suffering that occurs with surgery in the elderly and at least serve as a tool to help patients and families anticipate what to expect in patients undergoing surgery.
These predictive tools may help physicians, patients and families anticipate what to expect in patients undergoing surgery and in some cases may help with the informed decision on whether to proceed with surgery. A real value of either the frailty index or the composite used in the Robinson studies is that they are relatively brief and easy to administer in the surgeon’s office or preoperative clinic setting. But beyond the predictive value they currently lack specific action items. It’s one thing to say “this is a high risk patient”. It’s another to say “this is a risk factor that we can specifically do something about”. We’re hoping future research will help us avoid the very outcomes these tools are good at predicting. But this is a good start at changing the way we think about patients before surgery.
Robinson TN, Eiseman B, Wallace JI, et al. Redefining Geriatric Preoperative Assessment Using Frailty, Disability and Co-Morbidity. Annals of Surgery 2009; 250(3): 449-455, September 2009
Robinson TN, Wallace JI, Wu DS, et al. Accumulated Frailty Characteristics Predict Postoperative Discharge Institutionalization in the Geriatric Patient. J Am Coll Surg 2011; 213(1): 37-42, July 2011
Makary MA, Segeve DL, Pronovost PJ, et al. Frailty as a Predictor of Surgical Outcomes in Older Patients. Journal of the American College of Surgeons 2010;