The Evolution of Bat Vestibular Systems in the Face of Potential Antagonistic Selection Pressures for Flight and Echolocation

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Epidemiology of Shock in Contemporary Cardiac Intensive Care Units.

Background Clinical investigations of shock in cardiac intensive care units (CICUs) have primarily focused on acute myocardial infarction (AMI) complicated by cardiogenic shock (AMICS). Few studies have evaluated the full spectrum of shock in contemporary CICUs. Methods and Results The Critical Care Cardiology Trials Network is a multicenter network of advanced CICUs in North America. Anytime between September 2017 and September 2018, each center (n=16) contributed a 2-month snap-shot of all consecutive medical admissions to the CICU. Data were submitted to the central coordinating center (TIMI Study Group, Boston, MA). Shock was defined as sustained systolic blood pressurecardiogenic, distributive, hypovolemic, or mixed. Among 3049 CICU admissions, 677 (22%) met clinical criteria for shock. Shock type was varied, with 66% assessed as cardiogenic shock (CS), 7% as distributive, 3% as hypovolemic, 20% as mixed, and 4% as unknown. Among patients with CS (n=450), 30% had AMICS, 18% had ischemic cardiomyopathy without AMI, 28% had nonischemic cardiomyopathy, and 17% had a cardiac cause other than primary myocardial dysfunction. Patients with mixed shock had cardiovascular comorbidities similar to patients with CS. The median CICU stay was 4.0 days (interquartile range [IQR], 2.5-8.1 days) for AMICS, 4.3 days (IQR, 2.1-8.5 days) for CS not related to AMI, and 5.8 days (IQR, 2.9-10.0 days) for mixed shock versus 1.9 days (IQR, 1.0-3.6) for patients without shock (

Clinical Practice Patterns in Temporary Mechanical Circulatory Support for Shock in the Critical Care Cardiology Trials Network (CCCTN) Registry.

BACKGROUND: Temporary mechanical circulatory support (MCS) devices provide hemodynamic assistance for shock refractory to pharmacological treatment. Most registries have focused on single devices or specific etiologies of shock, limiting data regarding overall practice patterns with temporary MCS in cardiac intensive care units. METHODS: The CCCTN (Critical Care Cardiology Trials Network) is a multicenter network of tertiary CICUs in North America. Between September 2017 and September 2018, each center (n=16) contributed a 2-month snapshot of consecutive medical CICU admissions. RESULTS: Of the 270 admissions using temporary MCS, 33% had acute myocardial infarction-related cardiogenic shock (CS), 31% had CS not related to acute myocardial infarction, 11% had mixed shock, and 22% had an indication other than shock. Among all 585 admissions with CS or mixed shock, 34% used temporary MCS during the CICU stay with substantial variation between centers (range: 17%-50%). The most common temporary MCS devices were intraaortic balloon pumps (72%), Impella (17%), and veno-arterial extracorporeal membrane oxygenation (11%), although intraaortic balloon pump use also varied between centers (range: 40%-100%). Patients managed with intraaortic balloon pump versus other forms of MCS (advanced MCS) had lower Sequential Organ Failure Assessment scores and less severe metabolic derangements. Illness severity was similar at high- versus low-MCS utilizing centers and at centers with more advanced MCS use. CONCLUSIONS: There is wide variation in the use of temporary MCS among patients with shock in tertiary CICUs. While hospital-level variation in temporary MCS device selection is not explained by differences in illness severity, patient-level variation appears to be related, at least in part, to illness severity

Prognostic Performance of the IABP-SHOCK II Risk Score Among Cardiogenic Shock Subtypes in the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Risk stratification has potential to guide triage and decision-making in cardiogenic shock (CS). We assessed the prognostic performance of the IABP-SHOCK II score, derived in Europe for acute myocardial infarct-related CS (AMI-CS), in a contemporary North American cohort, including different CS phenotypes. METHODS: The Critical Care Cardiology Trials Network (CCCTN) coordinated by the TIMI Study Group is a multicenter network of cardiac intensive care units (CICU). Participating centers annually contribute ≥2 months of consecutive medical CICU admissions. The IABP-SHOCK II risk score includes age \u3e73 years, prior stroke, admission glucose \u3e191 mg/dl, creatinine \u3e1.5 mg/dl, lactate \u3e5 mmol/l, and post-PCI TIMI flow grade RESULTS: Of 17,852 medical CICU admissions 5,340 patients across 35 sites were admitted with CS. In patients with AMI-CS (n=912), the IABP-SHOCK II score predicted a \u3e3-fold gradient in in-hospital mortality (low risk = 26.5%, intermediate risk =52.2%, high risk = 77.5%, p CONCLUSIONS: In an unselected international multicenter registry of patients admitted with CS, the IABP- SHOCK II score only moderately predicted in-hospital mortality in a broad population of CS regardless of etiology or irrespective of right, left, or bi-ventricular involvement

Management and Outcomes of Cardiogenic Shock in Cardiac ICUs With Versus Without Shock Teams.

BACKGROUND: Single-center studies suggest that implementation of multidisciplinary cardiogenic shock (CS) teams is associated with improved CS survival. OBJECTIVES: The aim was to characterize practice patterns and outcomes in the management of CS across multiple centers with versus without shock teams. METHODS: The Critical Care Cardiology Trials Network is a multicenter network of cardiac intensive care units (CICUs) in North America. All consecutive medical admissions to each CICU (n = 24) were captured during annual 2-month collection periods (2017-2019; n = 6,872). Shock management and CICU mortality among centers with versus without shock teams were compared using inverse probability weighting. RESULTS: Ten of the 24 centers had shock teams. Among 1,242 CS admissions, 44% were at shock team centers. The groups were well-balanced with respect to demographics, shock etiology, Sequential Organ Failure Assessment score, biochemical markers of end organ dysfunction, and invasive hemodynamics. Centers with shock teams used more pulmonary artery catheters (60% vs 49%; adjusted odds ratio [OR]: 1.86; 95% CI: 1.47-2.35; P \u3c 0.001), less overall mechanical circulatory support (MCS) (35% vs 43%; adjusted OR: 0.74; 95% CI: 0.59-0.95; P = 0.016), and more advanced types of MCS (53% vs 43% of all MCS; adjusted OR: 1.73; 95% CI: 1.19-2.51; P = 0.005) rather than intra-aortic balloon pumps. The presence of a shock team was independently associated with lower CICU mortality (23% vs 29%; adjusted OR: 0.72; 95% CI: 0.55-0.94; P = 0.016). CONCLUSIONS: In this multicenter observational study, centers with shock teams were more likely to obtain invasive hemodynamics, use advanced types of MCS, and have lower risk-adjusted mortality. A standardized multidisciplinary shock team approach may improve outcomes in CS

Demographics, Care Patterns, and Outcomes of Patients Admitted to Cardiac Intensive Care Units: The Critical Care Cardiology Trials Network Prospective North American Multicenter Registry of Cardiac Critical Illness.

Importance: Single-center and claims-based studies have described substantial changes in the landscape of care in the cardiac intensive care unit (CICU). Professional societies have recommended research to guide evidence-based CICU redesigns. Objective: To characterize patients admitted to contemporary, advanced CICUs. Design, Setting, and Participants: This study established the Critical Care Cardiology Trials Network (CCCTN), an investigator-initiated multicenter network of 16 advanced, tertiary CICUs in the United States and Canada. For 2 months in each CICU, data for consecutive admissions were submitted to the central data coordinating center (TIMI Study Group). The data were collected and analyzed between September 2017 and 2018. Main Outcomes and Measures: Demographics, diagnoses, management, and outcomes. Results: Of 3049 participants, 1132 (37.1%) were women, 797 (31.4%) were individuals of color, and the median age was 65 years (25th and 75th percentiles, 55-75 years). Between September 2017 and September 2018, 3310 admissions were included, among which 2557 (77.3%) were for primary cardiac problems, 337 (10.2%) for postprocedural care, 253 (7.7%) for mixed general and cardiac problems, and 163 (4.9%) for overflow from general medical ICUs. When restricted to the initial 2 months of medical CICU admissions for each site, the primary analysis population included 3049 admissions with a high burden of noncardiovascular comorbidities. The top 2 CICU admission diagnoses were acute coronary syndrome (969 [31.8%]) and heart failure (567 [18.6%]); however, the proportion of acute coronary syndrome was highly variable across centers (15%-57%). The primary indications for CICU care included respiratory insufficiency (814 [26.7%]), shock (643 [21.1%]), unstable arrhythmia (521 [17.1%]), and cardiac arrest (265 [8.7%]). Advanced CICU therapies or monitoring were required for 1776 patients (58.2%), including intravenous vasoactive medications (1105 [36.2%]), invasive hemodynamic monitoring (938 [30.8%]), and mechanical ventilation (652 [21.4%]). The overall CICU mortality rate was 8.3% (95% CI, 7.3%-9.3%). The CICU indications that were associated with the highest mortality rates were cardiac arrest (101 [38.1%]), cardiogenic shock (140 [30.6%]), and the need for renal replacement therapy (51 [34.5%]). Notably, patients admitted solely for postprocedural observation or frequent monitoring had a mortality rate of 0.2% to 0.4%. Conclusions and Relevance: In a contemporary network of tertiary care CICUs, respiratory failure and shock predominated indications for admission and carried a poor prognosis. While patterns of practice varied considerably between centers, a substantial, low-risk population was identified. Multicenter collaborative networks, such as the CCCTN, could be used to help redesign cardiac critical care and to test new therapeutic strategies