Frailty can be easily assessed in aortic valve surgery patients using variables that are typically at the behest of most anesthesiologists, and the assessment can predict morbidity, mortality and hospital length of stay (LOS) in this fragile patient population.
“Previous research has shown that frailty is an independent risk factor for predicting morbidity and mortality in cardiac surgery patients [Eur J Cardiothorac Surg 2011;39:33-37],” noted Gary Esses, MD, a resident at the Icahn School of Medicine at Mount Sinai, in New York City. “Nevertheless, frailty screening has not been widely implemented in clinical practice. We believe this may be due to the fact that frailty is typically assessed using tests that are somewhat time-consuming, difficult to perform and require tools that may not be readily available in the clinical setting.
“We were particularly interested in looking at cardiac patients,” he continued, “because while the STS [Society of Thoracic Surgeons] and EuroSCORE [European System for Cardiac Operative Risk Evaluation] are really good at predicting risk, they do not include frailty as part of their assessment of patients when they’re having cardiac surgery. And there is work that has shown that frailty is independent of those risk scores for predicting morbidity and mortality.”
To help assess the utility of readily available chart information in determining frailty, Dr. Esses and his colleagues turned to the database of the American College of Surgeons National Surgical Quality Improvement Program, retrospectively identifying patients who underwent aortic valve replacement surgery. The investigators used a modified version of Ganapathi’s frailty index (J Thorac Cardiovasc Surg 2014;147:186-191.e1), which includes six variables:
- age (>70 years)
- body mass index (<18.5 kg/m2)
- anemia (hematocrit <35%)
- history of stroke
- hypoalbuminemia (<3.5 g/dL)
- partially or totally dependent functional status
Frailty was defined as a score of at least 2 and used as a predictor for morbidity, mortality and hospital LOS.
“The nice thing about this index is that it allowed us to retrospectively assess these patients because it uses data that are widely available,” Dr. Esses toldAnesthesiology News.
Of more than 2 million patients screened, the researchers identified 3,088 who underwent aortic valve replacement between 2006 and 2012. Of these, 800 patients (35%) had an index score of at least 2. “The most common ASA [American Society of Anesthesiologists] score for these patients was ASA IV, which makes sense given that they were having valve replacement surgery,” Dr. Esses explained.
One hundred fifteen patients (3.8%) died within 30 days and 675 experienced major morbidity (21.9%). “The most common morbidities seen were pneumonia, reintubation and reoperation,” he added.
As reported at the 2015 annual meeting of the ASA (abstract A2105), frail patients had increased risk for 30-day mortality (odds ratio [OR], 3.201; 95% CI, 2.071-4.407), major complication (OR, 1.951; 95% CI, 1.622-2.346) and unplanned reintubation (OR, 2.132; 95% CI, 1.490-3.050). Not surprisingly, frail patients also had a significantly longer median hospital LOS (12.0 days) than their nonfrail counterparts (7.0 days; P<0.01).
“To conclude, our research using the simple frailty index was consistent with previous research, which has shown that morbidity and mortality are increased in frail patients,” Dr. Esses said. “These data suggest that we can use a simple frailty index that doesn’t take that much time to predict morbidity and mortality in cardiac patients.”
Senior author Stacie G. Deiner, MD, associate professor of anesthesiology at Mount Sinai, noted that adding a simple frailty assessment might help change the way anesthesiologists look at high-risk cardiac surgery patients. “Traditionally, a comorbidity list has been the way that anesthesiologists conceive of whether or not someone is at risk for a complication,” Dr. Deiner said. “But of course, frailty transcends that to look at function and weakness.
“Looking beyond that, the field of surgery is moving to where medicine has been for a while, in thinking that frailty is important and may have some predictive value,” she said. “And I think we’re going to see frailty creeping into our risk-prediction indices in the future.” Future studies, she added, should be done to confirm these findings in a prospective cohort.
Javaid Iqbal, MD, consultant cardiologist in the South Yorkshire Cardiothoracic Centre at Northern General Hospital in Sheffield, England, told Anesthesiology News that the role of frailty is emerging as a prognostic marker for risk stratification and decision making. “We have recently shown that frail patients undergoing coronary angioplasty have increased length of hospital stay and mortality,” Dr. Iqbal said. “Though the results reported by Esses and colleagues are not surprising, they provide a much-needed reinforcement of the importance of frailty assessment. This study is also timely because we now have a less-invasive option of transcatheter aortic valve replacement for patients who may be too frail to undergo conventional surgical aortic valve replacement.”
Dr. Iqbal also acknowledged the importance of a simplified score to assess frailty that can be incorporated into routine care. “Undoubtedly,” he said, “we need prospective clinical studies to evaluate different frailty scores. However, it is reassuring that the importance of frailty is being recognized in the multidisciplinary heart teams, including cardiologists, surgeons and anesthesiologists.”