Acute Physiology and Chronic Health Evaluation (APACHE) III outcome prediction after major vascular surgery

Benchmarking a Center of Excellence in Vascular Surgery: Using Acute Physiology and Chronic Health Evaluation II to Validate Outcomes in a Tertiary Care Institute

OBJECTIVE

The Society of Vascular Surgery (SVS) has made it a top priority to implement verification of vascular "centers of excellence". Our institutional aortic network was established in 2008 in order to standardize care of patients with suspected acute aortic pathology. The implementation and success of this program has been previously reported. We sought to use our experience as a benchmark for which to develop prognostic modeling to quantify clinical status upon admission and help predict outcomes. Our objective was to validate the Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system using a cohort of aortic emergencies transferred by an organized transfer network.

METHOD

This was a retrospective, single institution review of patients transferred through an institutional aortic network for acute aortic pathology from 2017-2018. Demographics, comorbidities, aortic diagnosis, APACHE II score, as well as 30-day mortality were recorded. Associations with 30-day mortality were evaluated using two-sample t-tests, ANOVA models, Pearson chi-square tests and Fisher exact tests. Receiver operating characteristic (ROC) curves were fit overall and by pathology to predict 30-day mortality by Apache II total score.

RESULTS

There were 395 consecutive transfers were identified. The mean age was 64.7 years. Diagnoses included Type A Dissection (n = 134), Type B (n = 81), Aortic Aneurysm (n = 122), and PAU/IMH (n = 27). Mean APACHE II score on arrival was 12. Overall there were 53 deaths (13.4%) in the cohort. Patients that died had significantly higher Apache II total scores (11.3 vs 16.5, P < .001). The area under the receiver operator characteristic (ROC) curve (AUC) was .66 for the full cohort, indicating a poor clinical prediction test.

CONCLUSION

APACHE II score is a poor predictor of 30-day mortality in a large transfer network accepting all aortic emergencies. The authors believe further refining a prognostic model for diverse population will not only help in predicting outcomes but to objectively quantify illness severity in order to have a basis for comparison among institutions and verification of "centers of excellence".

A Multidimensional Approach of Surgical Mortality Assessment and Stratification (Smatt Score)

Surgical mortality is the most significant measure of outcome in surgical healthcare. The objective was to assess surgical 30 days mortality and improve the identification of predictors for personalized risk stratification of patients undergoing elective and emergency surgery. The study was conducted as a single-center cohort retrospective observational study, based on the analysis of data collected from patients surgically treated from 2002 to 2014 in a multi-disciplinary research and care referral hospital with global case mix of 1.27. The overall in-hospital mortality rate was 1.89% (95% CI 1.82–1.95). In the univariable analysis, numerous predictors were significantly associated with in-hospital death following surgery. In the multivariable model, age, BMI (Body Mass Index), ASA score, department, planned surgical complexity, surgical priority, previous surgeries in the same hospitalization, cardiovascular, pulmonary, hepato-renal comorbidities, drug intolerance, cancer and AIDS were independently associated with mortality after surgery. At logistic regression, the computed SMATT score (graded 0–100), generated on the basis of multivariate analysis, demonstrated a good discrimination (10-fold cross-validated AUC-ROC 0.945, 95%CI 0.941–0.948) and correctly classified 98.5% of those admissions with a probability of death >50%. The novel SMATT score, based on individual preoperative and surgical factors, accurately predicts mortality and provides dynamic information of the risk in redo/reoperative surgery.

Cefepime is Associated with Acute Encephalopathy in Critically Ill Patients: A Retrospective Case-Control Study

BACKGROUND

Acute encephalopathy (AE) is a common complication of critical illness and is associated with increased short and long-term mortality. In this study, we evaluated the role of cefepime in causing AE.

METHODS

Retrospective case-control study involving consecutive patients enrolled in the intensive care units (ICUs) of Mayo Clinic Rochester, MN between July 1, 2004 and December 31, 2015. AE was defined by the presence of delirium or depressed level of consciousness in the absence of deep sedation. Controls were identified as patients not developing AE and were matched by propensity score for age, Charlson Comorbidity Index, 24-h Apache III score and invasive ventilation use.

RESULTS

The total number of eligible ICU admissions during our study period was 152,999. AE was present in 57,726 (37.7%) with a median AE duration of 17 (interquartile range [IQR] 4.0-51.8) hours. We matched 14,645 cases with AE with the same number of controls. Cefepime was used in 1241 (4.2%) patients and its use was associated with greater incidence of AE [713 (4.9%) vs 528 (3.6%), p < 0.001] and duration [unit estimate 0.73; (95% CI 0.542-0.918)]. On multivariate analysis, cefepime was associated with an increased likelihood of AE after controlling for shock, midazolam infusion and acute kidney injury [OR 1.24 (95% CI 1.10-1.27)]. These associations were also present after controlling for prior chronic kidney disease.

CONCLUSION

The use of cefepime is associated with increased likelihood and duration of AE. These associations are stronger among patients with impaired renal function, but can also occur in patients without renal impairment.

A Systems Approach to Design and Implementation of Patient Assessment Tools in the Inpatient Setting

Failure to rescue events, or events involving preventable deaths from complications, are a significant contributor to inpatient mortality. While many interventions have been designed and implemented over several decades, this patient safety issue remains at the forefront of concern for most hospitals. In the first part of this study, the development and implementation of one type of highly studied and widely adopted rescue intervention, algorithm-based patient assessment tools, is examined. The analysis summarizes how a lack of systems-oriented approaches in the design and implementation of these tools has resulted in suboptimal understanding of patient risk of mortality and complications and the early recognition of patient deterioration. The gaps identified impact several critical aspects of excellent patient care, including information-sharing across care settings, support for the development of shared mental models within care teams, and access to timely and accurate patient information. This chapter describes the use of several system-oriented design and implementation activities to establish design objectives, model clinical processes and workflows, and create an extensible information system model to maximize the benefits of patient state and risk assessment tools in the inpatient setting. A prototype based on the product of the design activities is discussed along with system-level considerations for implementation. This study also demonstrates the effectiveness and impact of applying systems design principles and practices to real-world clinical applications.

Risk factors and outcomes of critically ill patients with acute brain failure: A novel end point

OBJECTIVE

To determine the incidence, risk factors and outcomes of acute brain failure (ABF) in a mixed medical and surgical cohort of critically ill patients and its effect on ICU & hospital mortality.

DESIGN

Observational electronic medical record (EMR) based retrospective cohort study of critically ill patients admitted to the ICU between 2006 and 2013.

SETTING

Tertiary academic medical center.

PATIENTS

Consecutive adult (>18years) critically ill patients admitted to medical and surgical ICUs. Patients admitted to the Neuroscience, Pediatric and Neonatal ICUs were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

ABF was defined by the presence of delirium (positive CAM-ICU) or depressed level of consciousness (by abnormal GCS and FOUR scores) in the absence of deep sedation (RASS<-3). Severity of ABF was categorized as grade I if there was delirium with GCS consistently >8 and grade II if the GCS was ≤8 with or without delirium during the ICU hospitalization. ABF duration was not used for this study. Univariate and multivariable analyses were used to access the factors associated with the development of ABF and its effect on short and long term mortality. Of 67,333 ICU patients included in the analysis, ABF was present in 30,610 (44.6%). Patients with ABF had an isolated delirium in 1985 (6.5%) patients, isolated depressed consciousness in 18,323 (59.9%), and both delirium and depressed consciousness in 10,302 (33.6%) patients. When adjusted for comorbidities and severity of illness ABF was associated with increased hospital (OR 3.47; 95% CI 3.19-3.79), and at one year (OR 2.36; 95% CI 2.24-2.50) mortality. Both hospital and one year mortality correlated with the increased severity of ABF. The factors most strongly associated with ABF were pre-admission dementia (OR 7.86; 95% CI 6.15-10.19) and invasive ventilation (OR 2.32; 95% CI 2.24-2.40) but older age, female sex, presence of liver disease, renal failure, diabetes mellitus, malignancy and COPD were also associated with increased risk of ABF.

CONCLUSIONS

ABF is a common complication of critical illness and is associated with increased short and long term mortality. The risk of ABF was particularly high in older patients with baseline dementia, COPD, diabetes, liver and renal disease and those treated with invasive mechanical ventilation.

APACHE III score on ICU admission predicts hospital mortality after open thoracoabdominal and open abdominal aortic aneurysm repair

BACKGROUND

No prior studies, to our knowledge, have examined the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) III score in predicting mortality of patients undergoing open thoracoabdominal aortic aneurysm (TAAA) or open abdominal aortic aneurysm (AAA) repair. We sought to evaluate APACHE III scores in the prediction of postoperative mortality in elective TAAA and AAA repairs.

METHODS

Over a 9-year period (July 1998 through June 2007), prospective data (demographics, admitting diagnosis, APACHE III score, intensive care unit [ICU] and hospital length of stay, ICU and hospital mortality) were collected by a dedicated APACHE III coordinator for all patients admitted to a tertiary academic surgical ICU (20 beds). Observational and comparative analyses were performed. Emergent repairs for ruptured aneurysms were excluded from the study.

RESULTS

Forty-one patients underwent open elective repair of TAAA and 404 underwent open elective repair of AAA. Mean age of the TAAA group was 63.4 ± 9.8 years and the AAA group was 70.3 ± 8.3 years. Mean APACHE III score was 54 (range: 10-103) for the TAAA group and 45 (range: 11-103) for the AAA group. The in-hospital mortality rate for TAAA patients was 4.9% (n = 2) and for AAA patients was 2.0% (n = 8). Mean APACHE III scores on ICU admission were significantly greater in nonsurvivors versus survivors (79 vs. 45, p < 0.0001). For the entire patient cohort, the APACHE III score on ICU admission was an excellent discriminator of hospital mortality (receiver operating characteristic and area under the curve 0.92 [standard error of 0.05, 95% CI: 0.83-1.0]).

CONCLUSIONS

APACHE III is an accurate predictor of survival to hospital discharge in both open elective TAAA and AAA repairs.