Derivation and validation of thoracic sarcopenia assessment in patients undergoing thoracic endovascular aortic repair.

OBJECTIVE: Sarcopenia, as assessed by computed tomography (CT)-based measurements of muscle mass, is an objective and patient-specific indicator of frailty, which is an important predictor of operative morbidity and mortality. Studies to date have primarily focused on psoas-defined sarcopenia, which may not be valid among patients with thoracic aortic disease. Using psoas sarcopenia as the reference for sarcopenia, the purpose of this study was to create and to validate a new thoracic-level method of measuring sarcopenia as a novel method to assess frailty among patients undergoing thoracic endovascular aortic repair. METHODS: Prospectively collected data of patients undergoing thoracic endovascular aortic repair for thoracic aortic dissection, aneurysm, or injury using a conformable thoracic graft were reviewed. Patients with preoperative abdominal and thoracic CT imaging were included. Thoracic muscle mass was measured on axial images at the T12 level using our newly established standardized computer-assisted protocol. Psoas sarcopenia was measured at the L3 level using standard methods. Optimal sex-specific diagnostic T12 measurements were determined by receiver operating characteristic (ROC) curve analysis. A subset of scans were reviewed in duplicate by two trained observers and intraobserver and interobserver reliability tested by intraclass correlation coefficient. Agreement between T12 and L3 sarcopenia was tested by Cohen κ (scale, 0-1). RESULTS: There were 147 patients included for analysis, including 34 dissection, 80 trauma, and 33 aneurysm patients. ROC curve analysis yielded sarcopenic cutoff values of 106.00 cm2/m2 for women and 110.00 cm2/m2 for men at the T12 level. Based on ROC curve analysis, overall accuracy of T12 measurements was high (area under ROC curve, 0.91 for men and 0.90 for women). Quantitative interobserver and intraobserver reliability yielded excellent intraclass correlation coefficient values (>0.95). Qualitative interobserver reliability yielded nearly perfect Cohen κ values (>0.85). Qualitative intraobserver reliability of calculating sarcopenia at both the T12 and L3 levels was fair for both readers (0.361 and 0.288). There was additionally a general correlation between changes in muscle area at L3 with changes at T12 during 48 months. CONCLUSIONS: Thoracic sarcopenia can be readily and reliably reproduced from CT-derived measurement of T12-level muscle area. This approach may be used as an alternative method to objectively define sarcopenia in patients without abdominal CT imaging. Future studies to assess the predictability of thoracic vs abdominal sarcopenia on postoperative outcomes will enhance the utility of these tools.

Early Treatment at a Referral Center Improves Outcomes for Patients with Acute Vascular Disease.

BACKGROUND: Patients with acute vascular disease frequently need specialized management that may require transfer to a vascular referral center. Although transfer may be medically necessary, it can delay definitive care and is an indicator of incorrect triage to the initial hospital. Regionalization of acute vascular care could improve patient triage and subsequent outcomes. To evaluate the potential benefit from regionalization, we analyzed outcomes of patients treated for acute vascular disease at vascular referral centers. METHODS: Using a statewide database capturing all inpatient admissions in Maryland during 2013-2015, patients undergoing noncardiac vascular procedures on an acute basis were identified. Patients admitted to a vascular referral center were stratified by admission status as direct or transfer. The primary outcome was inpatient mortality, and the secondary outcome was resource use. Patient groups were compared by univariable analyses, and the effect of admission status on mortality was assessed by multivariable logistic regression. RESULTS: Of 4,873 patients with acute vascular disease managed at vascular referral centers, 2,713 (56%) were admitted directly, whereas 2,160 (44%) were transferred. Transfers to referral centers accounted for 71% of all interhospital transfers. The transfer-group patients were older, had more comorbidities, and higher illness severities. Patients who were transferred had higher mortality (14% vs. 9%, P < 0.0001), longer hospital lengths of stay, greater critical care-resource utilization, and higher costs. After adjusting for demographics, comorbidities, and illness severity, transfer status was independently associated with higher inpatient mortality. CONCLUSIONS: Primary treatment at a referral center is independently associated with improved outcomes for patients with acute vascular disease. Direct admission or earlier triage to a specialty center may improve patient and system outcomes and could be facilitated by standardization and regionalization of complex acute vascular care.

Defining the burden, scope, and future of vascular acute care surgery.

OBJECTIVE: The paradigm of acute care surgery has revolutionized nonelective general surgery. Similarly, nonelective vascular surgery may benefit from specific management and resource capabilities. To establish the burden and scope of vascular acute care surgery, we analyzed the characteristics and outcomes of patients hospitalized for vascular surgical procedures in Maryland. METHODS: A retrospective analysis of a statewide inpatient database was performed to identify patients undergoing noncardiac vascular procedures in Maryland from 2009 to 2013. Patients were stratified by admission acuity as elective, urgent, or emergent, with the last two groups defined as acute. The primary outcome was inpatient mortality, and secondary outcomes were critical care and hospital resource requirements. Groups were compared by univariate analyses, with multivariable analysis of mortality based on acuity level and other potential risk factors for death. RESULTS: Of 3,157,499 adult hospital admissions, 154,004 (5%) patients underwent a vascular procedure; most were acute (54% emergent, 13% urgent), whereas 33% were elective. Acute patients had higher rates of critical care morbidity and required more hospital resource utilization. Admission for acute vascular surgery was independently associated with mortality (urgent odds ratio, 2.1; emergent odds ratio, 3.0). CONCLUSIONS: The majority of inpatient vascular care in Maryland is for acute vascular surgery, which is an independent risk factor for mortality. Acute vascular surgical care entails greater critical care and hospital resource utilization and-similar to emergency general surgery-may benefit from dedicated training and practice models.

A new aortic injury score predicts early rupture more accurately than clinical assessment.

OBJECTIVE: The optimal timing for repair of a high-grade blunt thoracic aortic injury (BTAI) is uncertain. Delayed repair is common and associated with improved outcomes, but some lesions may rupture during observation. To determine optimal patient selection for appropriate management, we developed a pilot clinical risk score to evaluate aortic stability and predict rupture. METHODS: Patients presenting in stable condition with Society for Vascular Surgery grade III or IV BTAI diagnosed on computed tomography (CT) were retrospectively reviewed. To determine clinical and radiographic factors associated with aortic rupture, patients progressing to aortic rupture (defined by contrast extravasation on CT or on operative or autopsy findings) were compared with those who had no intervention ≤48 hours of admission. A model targeting 100% sensitivity for rupture was generated and internally validated by bootstrap analysis. Clinical utility was tested by comparison with clinical assessment by surgeons experienced in BTAI management who were provided with CT images and clinical data but were blinded to outcome. RESULTS: The derivation cohort included 18 patients whose aorta ruptured and 31 with stable BTAI. There was no difference in age, gender, injury mechanism, nonchest injury severity, blood pressure, or Glasgow Coma Scale on admission between patient groups. As dichotomous factors, admission lactate >4 mM, posterior mediastinal hematoma >10 mm, and lesion/normal aortic diameter ratio >1.4 on the admission CT were independently associated with aortic rupture. The model had an area under the receiver operator curve of .97, and in the presence of any two factors, was 100% sensitive and 84% specific for predicting aortic rupture. No aortic lesions ruptured in patients with fewer than two factors. In contrast, clinical assessment had lower accuracy (65% vs 90% total accuracy, P < .01). CONCLUSIONS: This novel risk score can be applied on admission using clinically relevant factors that incorporate patient physiology, size of the aortic lesion, and extent of the mediastinal hematoma. The model reliably identifies and distinguishes patients with high-grade BTAI who are at risk for early rupture from those with stable lesions. Although preliminary, because it is more accurate than clinical assessment alone, the score may improve patient selection for emergency or delayed intervention.