Simplified Frailty Index to Predict Adverse Outcomes and Mortality in Vascular Surgery Patients

Validation of a frailty index in patients undergoing curative surgery for urologic malignancy and comparison with other risk stratification tools

OBJECTIVE

To retrospectively validate and compare a modified frailty index predicting adverse outcomes and other risk stratification tools among patients undergoing urologic oncological surgeries.

MATERIALS AND METHODS

The American College of Surgeons National Surgical Quality Improvement Program was queried from 2005 to 2013 to identify patients undergoing cystectomy, prostatectomy, nephrectomy, and nephroureterectomy. Using the Canadian Study of Health and Aging Frailty Index, 11 variables were matched to the database; 4 were also added because of their relevance in oncology patients. The incidence of mortality, Clavien-Dindo IV complications, and adverse events were assessed with patients grouped according to their modified frailty index score.

RESULTS

We identified 41,681 patients who were undergoing surgery for presumed urologic malignancy. Patients with a high frailty index score of >0.20 had a 3.70 odds of a Clavien-Dindo IV event (CI: 2.865-4.788, P<0.0005) and a 5.95 odds of 30-day mortality (CI: 3.72-9.51, P<0.0005) in comparison with nonfrail patients after adjusting for race, sex, age, smoking history, and procedure. Using C-statistics to compare the sensitivity and specificity of the predictive ability of different models per risk stratification tool and the Akaike information criteria to assess for the fit of the models with the data, the modified frailty index was comparable or superior to the Charlson comorbidity index but inferior to the American Society of Anesthesiologists Risk Class in predicting 30-day mortality or Clavien-Dindo IV events. When the modified frailty index was augmented with the American Society of Anesthesiologists Risk Class, the new index was superior in all aspects in comparison to other risk stratification tools.

CONCLUSION

Existing risk stratification tools may be improved by incorporating variables in our 15-point modified frailty index as well as other factors such as walking speed, exhaustion, and sarcopenia to fully assess frailty. This is relevant in diseases such as kidney and prostate cancer, where surveillance and other nonsurgical interventions exist as alternatives to a potentially complicated surgery. In these scenarios, our modified frailty index augmented by the American Society of Anesthesiologists Risk Class may help inform which patients have increased surgical complications that may outweigh the benefit of surgery although this index needs prospective validation.

Risk stratification and outcomes of women undergoing surgery for ovarian cancer

OBJECTIVE

Cytoreduction for ovarian cancer is associated with substantial morbidity. We examined the outcome of patients undergoing surgery for ovarian cancer to determine if there are sub-groups of patients who may benefit from alternative treatments.

METHODS

The National Surgical Quality Improvement Program database was used to identify women who underwent surgery for ovarian cancer from 2005-2012. Multivariable logistic regression models were used to examine the effect of age, race, functional status, ASA class, preoperative albumin and performance of extended cytoreductive procedures on morbidity, mortality and resource utilization.

RESULTS

A total of 2870 women were identified. The perioperative complication rate increased from 9.5% in women <50years, to 13.4% in those age 60-69years, and 14.6% in women ≥70years (P<0.0001). Similarly, complications rose from 7.3% in those who did not require any extended procedures to 12.9% after 1 procedure, 28.4% for those who had 2, and 30.0% in women who underwent ≥3 extended procedures (P<0.0001). In a series of multivariable models, the number of extended cytoreductive procedures performed and preoperative albumin were the factors most consistently associated with morbidity. Using a series of model fit statistics, compared to chance alone, the ability to predict any complication increased by 27.4% when procedure score was analyzed, 22.0% with preoperative albumin, 11% with age, and 4% with functional status.

CONCLUSIONS

While preoperative clinical and demographic factors may help predict the risk of adverse outcomes for women undergoing surgery for ovarian cancer, performance of extended cytoreductive procedures is the strongest risk factor for complications.

Predictors of Clavien 4 Complications and Mortality After Necrosectomy: Analysis of the NSQIP Database

BACKGROUND

Acute severe pancreatitis is one of the most common gastrointestinal reasons for admission to hospitals in the USA. Up to 20 % of these patients will progress to necrotizing pancreatitis requiring intervention. The aim of this study is to identify specific preoperative factors for the development of Clavien 4 complications and mortality in patients undergoing pancreatic necrosectomy.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) participant use files were reviewed from 2007 to 2012 to identify patients who underwent a pancreatic necrosectomy. Postoperative complications were stratified into Clavien 4 (ICU level complications) and Clavien 5 (mortality). Univariate and multivariate analyses were performed.

RESULTS

A total of 1156 patients underwent a pancreatic necrosectomy from 2007 to 2012. Overall, 42 % of patients experienced a Clavien 4 complication. Mortality rate was 9.5 %. Nonindependent functional status and ASA class were highly significant (p < 0.001) in univariate analysis. Frailty and emergency surgery status (p < 0.001), as well as increased blood urea nitrogen (BUN) and alkaline phosphatase and decreased albumin (p < 0.05) demonstrated independent significance of Clavien 4 complications and mortality in multivariate analysis.

CONCLUSION

This study identified specific preoperative variables that place patients at increased risk of Clavien 4 complications and mortality after necrosectomy. Identification of high-risk patients can aid in selection of appropriate treatment strategies and allow for informed preoperative discussion regarding surgical risk.

Effect of frailty on short- and mid-term outcomes in vascular surgical patients

BACKGROUND

Frailty is a multidimensional vulnerability resulting from age-associated decline. The impact of frailty on outcomes was assessed in a cohort of vascular surgical patients.

METHODS

The study included patients aged over 65 years with length of hospital stay (LOS) greater than 2 days, who were admitted to a tertiary vascular unit over a single calendar year. Demographics, mode of admission, diagnosis, mortality, LOS and discharge destination were recorded, as well as a variety of frailty-specific characteristics. The impact of frailty on LOS, discharge destination, survival and readmission rate was assessed using multivariable regression techniques. The ability of the models to predict these outcomes was also assessed.

RESULTS

In total, 413 patients of median age 77 years were followed for a median of 18 (range 12-24) months. The in-hospital, 3- and 12-month mortality rates were 3·6, 8·5 and 13·8 per cent respectively. Receiver operating characteristic (ROC) curve analysis revealed that frailty-based regression models were excellent predictors of 12-month mortality (area under the ROC curve (AUC) = 0·81), prolonged LOS (AUC = 0·79) and discharge to a care institution (AUC = 0·84). A simple additive frailty score using six key features retained strong predictive power for 12-month mortality (AUC = 0·83), discharge to a care institution (AUC = 0·78) and prolonged LOS (AUC = 0·74). This frailty score was also strongly associated with readmission rates (P < 0·001).

CONCLUSION

Frailty in vascular surgery patients predicts a multiplicity of poorer outcomes. Optimal management should include identification of at-risk patients and treatment of modifiable risk factors.

The impact of functional dependency on outcomes after complex general and vascular surgery

OBJECTIVE

To describe the outcomes of functionally dependent patients who undergo major general or vascular surgery and to determine the relationship between functional health status and early postoperative outcomes.

BACKGROUND

In contrast to frailty, functional health status is a relatively easy entity to define and to measure and therefore may be a more practical variable to assess in patients who are being considered for major surgery. To date, few studies have assessed the impact of functional health status on surgical outcomes.

METHODS

Patients undergoing 1 of 10 complex general or vascular operations were extracted from the 2005 to 2010 America College of Surgeons National Surgical Quality Improvement Program database. Propensity score techniques were used to match patients with and without preoperative functional dependency on known patient- and procedure-related factors. The postoperative outcomes of this matched cohort were then compared.

RESULTS

A total of 10,246 functionally dependent surgical patients were included for analysis. These patients were more acutely and chronically ill than functionally independent patients, and they had higher rates of mortality and morbidity for each of the 10 procedures analyzed. Propensity-matching techniques resulted in the creation of a cohort of functionally independent and dependent patients who were well matched for known patient- and procedure-related variables. Dependent patients from the matched cohort had a 1.75-fold greater odds of postoperative death (95% confidence interval: 1.54-1.98, P < 0.0001) than functionally independent patients.

CONCLUSIONS

Preoperative functional dependency is an independent risk factor for mortality after major operation. Functional health status should be routinely assessed in patients who are being considered for complex surgery.

External validation of the Ferguson pulmonary risk score for predicting major pulmonary complications after oesophagectomy†

OBJECTIVES

Pulmonary complications remain a frequent cause of morbidity in patients undergoing oesophagectomy. Risk screening tools assist in patient stratification. Ferguson proposed a risk score system to predict major pulmonary complications after oesophagectomy. Our objective was to externally validate this risk score system.

METHODS

We analysed our institutional database for patients undergoing oesophagectomy for cancer from August 2009 to December 2012. We analysed patients who had complete documentation of variables used in the Ferguson risk score calculation: forced expiratory volume in the 1 s, diffusion capacity of the lung for carbon monoxide, performance status and age. One hundred and thirty-six patients qualified for analysis in the validation study. Outcome variables measured included major pulmonary complications, defined as need for reintubation for respiratory failure and pneumonia. The risk score was then calculated for each individual based on the model. Incidence of major pulmonary events was assessed in the five risk class groupings to assess the discriminative ability of the Ferguson score.

RESULTS

Major pulmonary complications occurred in 35% of patients (47/136). Overall mortality was 6% (8/136). Patients were grouped into five risk categories according to their Ferguson pulmonary risk score: 0-2, 8 patients (6%); 3-4, 24 patients (18%); 5-6, 49 patients (36%); 29 patients (21%); 9-14, 26 patients (19%). The incidence of major pulmonary complications in these categories was 0, 17, 20, 41 and 77%, respectively. The accuracy of the risk score system for predicting major pulmonary complications was 76% (P < 0.0001).

CONCLUSIONS

This pulmonary risk scoring system is a reliable instrument to be used during the preoperative phase to differentiate patients who may be at higher risk for pulmonary complications after oesophagectomy. These data can assist in patient selection, and in patient education/informed consent and can guide postoperative management.

The implication of frailty on preoperative risk assessment

PURPOSE OF REVIEW

Frailty, a state of decreased homeostatic reserve, is characterized by dysregulation across multiple physiologic and molecular pathways. It is particularly relevant to the perioperative period, during which patients are subject to high levels of stress and inflammation. This review aims to familiarize the anesthesiologist with the most current concepts regarding frailty and its emerging role in preoperative assessment and risk stratification.

RECENT FINDINGS

Current literature has established frailty as a significant predictor of operative complications, institutionalization, and death among elderly surgical patients. A variety of scoring systems have been proposed to preoperatively identify and assess frail patients, though they differ in their clinical utility and prognostic ability. Additionally, evidence suggests an evolving potential for preoperative intervention and modification of the frailty syndrome.

SUMMARY

The elderly are medically complex and heterogeneous with respect to operative risk. Recent advances in the concept of frailty provide an evidence-based framework to guide the anesthesiologist in the perioperative management, evaluation, and risk stratification of older surgical patients.

Frailty and perioperative outcomes: a narrative review

BACKGROUND

Frailty has no single universally accepted definition or method for assessment. It is commonly defined from a physiological perspective as a disruption of homeostatic mechanisms ultimately leading to a vulnerable state. Numerous scoring indices and assessments exist to assist clinicians in determining the frailty status of a patient. The purpose of this review is to discuss the relationship between frailty and perioperative outcomes in surgical patients.

PRINCIPAL FINDINGS

We performed a review to determine the association of frailty with perioperative outcomes in patients undergoing a wide variety of surgical procedures. A scoping literature search was performed to capture studies from MEDLINE(®), EMBASE™, and CENTRAL (Cochrane), which resulted in locating 175 studies across the three electronic databases. After an article screening process, 19 studies were found that examined frailty and perioperative outcomes. The studies used a range of assessments to determine frailty status and included patients in a variety of surgical fields. Regardless of surgical population and method of frailty assessment, a relationship existed between adverse perioperative outcomes and frailty status. Frail patients undergoing surgical procedures had a higher likelihood than non-frail patients of experiencing mortality, morbidity, complications, increased hospital length of stay, and discharge to an institution.

CONCLUSIONS

Patients undergoing surgery who are deemed frail, regardless of the scoring assessment used, have a higher likelihood of experiencing adverse perioperative outcomes. With the lack of a unified definition for frailty, further research is needed to address which assessment method is most predictive of adverse postoperative outcomes.