Faculty Bibliography

Over the past half century, coronary care units have expanded from specialized ischemia arrhythmia monitoring units into intensive care units (ICUs) for acutely ill and medically complex patients with a primary cardiac diagnosis. Patients admitted to contemporary coronary intensive care units (CICUs) are at risk for common and preventable critical care complications, yet many CICUs have not adopted standard-of-care prevention protocols and practices from general ICUs. In this article, we (1) review evidence-based interventions and care bundles that reduce the incidence of ventilator-associated pneumonia, excess sedation during mechanical ventilation, central line infections, stress ulcers, malnutrition, delirium, and medication errors and (2) recommend pragmatic adaptations for common conditions in critically ill patients with cardiac disease, and (3) provide example order sets and practical CICU protocol implementation strategies.

Patients with a durable, continuous-flow left ventricular assist device (LVAD) are commonly prescribed the combination of an oral anticoagulant and an oral antiplatelet agent as prophylaxis against device thrombosis and systemic embolic events. Current International Society of Heart and Lung (ISHLT) guidelines recommend warfarin with an INR goal of 2-3 and concomitant aspirin 81-325 mg daily for patients with a HeartMate II LVAD. Unfortunately, gastrointestinal (GI) bleeding is very common in these patients because of multiple factors including the development of arteriovenous malformations and acquired von Willebrand syndrome. If this bleeding cannot be corrected through interventional measures, it then requires at least temporary, and potentially permanent, cessation of antiplatelet or anticoagulant therapy. Patients who continue to bleed while off all antithrombotic therapies present a clinical challenge. We describe the successful management of a patient with refractory GI bleeding through the use of inhaled desmopressin.

Acquired von Willebrand disease increases bleeding risk in patients implanted with a continuous-flow left ventricular assist device. Lower aspirin (ASA) doses decrease the risk of bleeding without an increased risk of embolic events. No published studies in the United States have compared the incidence of bleeding and thrombotic events between antithrombotic regimens with and without ASA. A single-center, retrospective analysis was conducted of adult patients implanted with a HeartMate II (HM II). Patients received warfarin and ASA 81 mg daily or warfarin alone. The primary end-point was a composite of death, bleeding events, and thrombotic events from the date of HM II implantation to first event or 18 months. Secondary end-points included the individual components of the primary end-point and the proportion of patients alive with HM II or transplanted. The Wilcoxon rank sum test and Fisher's exact test were used for statistical analysis. Of the 76 patients meeting inclusion criteria, 44 received warfarin and ASA and 32 received warfarin alone. Baseline characteristics were similar between groups. Warfarin alone was not associated with an increased risk of the primary composite outcome (53 vs. 59%, respectively, p = 0.64). No significant difference was observed in any bleeding event (34 vs. 43%, respectively, p = 0.48) nor any thrombotic event (9 vs. 11%, respectively, p = 1.00) with warfarin alone compared with warfarin and ASA. Elimination of antiplatelet therapy from the HM II antithrombotic regimen was associated with no significant difference in the composite outcome of bleeding events, thrombotic events, or death, nor the individual components of each end-point.

There is insufficient data on patients with small body size to determine if this should be considered a risk factor for continuous-flow left ventricular assist device (CF-LVAD) support. We sought to evaluate survival outcomes, adverse events, and functional status of CF-LVAD patients with body surface area (BSA) <1.5 m in a large national registry. Adults with BSA < 1.5 m (n = 128) implanted with a HeartMate II (HMII)-LVAD from the Interagency Registry for Mechanically Assisted Circulatory Support registry from April 2008 to December 2012 formed this cohort. Outcomes were compared with HMII bridge to transplant (BTT) and destination therapy (DT) post approval studies. The majority of patients were female (n = 106, 83%). A total of 64% (n = 82) were implanted for BTT and 36% (n = 46) for DT. The median BSA (range) was 1.44 (1.19-1.49) and 1.45 (1.25-1.49) m for BTT and DT, respectively. Overall survival 1 year post implant was 81% +/- 5% for BTT and 84% +/- 6% for DT. The most common adverse events for BTT and DT patients were bleeding (0.91, 0.88 events/patient year) and driveline infection (16%, 0.28 events/patient year). Six months post implantation, 87% of BTT and 77% of DT patients were New York Heart Association functional class I or II. Post implant survival, functional status improvement, and adverse event profile for adult BTT and DT HMII patients with BSA < 1.5 m are favorable and comparable with outcomes published in the overall patient population.

The cardiac intensive care unit (CICU) has changed considerably over time and now serves a unique patient population with a high burden of cardiovascular and noncardiovascular critical illness. Patient complexity and technological evolutions in the CICU have catalyzed the development of critical care cardiology, a fledgling discipline that combines specialization in cardiovascular diseases with knowledge and experience in critical care medicine. Numerous uncertainties and challenges threaten to stymie the growth of this field. A multidisciplinary dialogue focused on the best care design for the CICU patient is needed as we consider alternative approaches to clinical training, staffing, and investigation in this rapidly evolving arena.

BACKGROUND:Clinical practice guidelines recommend admitting patients with stable non-ST-segment elevation acute coronary syndrome (NSTE ACS) to telemetry units, yet up to two-thirds of patients are admitted to higher-acuity critical care units (CCUs). The outcomes of patients with stable NSTE ACS initially admitted to a CCU vs a cardiology ward with telemetry have not been described. METHODS:We used population-based data of 7,869 patients hospitalized with NSTE ACS admitted to hospitals in Alberta, Canada, between April 1, 2007, and March 31, 2013. We compared outcomes among patients initially admitted to a CCU (n=5,141) with those admitted to cardiology telemetry wards (n=2,728). RESULTS:Patients admitted to cardiology telemetry wards were older (median 69 vs 65years, P<.001) and more likely to be female (37.2% vs 32.1%, P<.001) and have a prior myocardial infarction (14.3% vs 11.5%, P<.001) compared with patients admitted to a CCU. Patients admitted directly to cardiology telemetry wards had similar hospital stays (6.2 vs 5.7days, P=.29) and fewer cardiac procedures (40.3% vs 48.5%, P<.001) compared with patients initially admitted to CCUs. There were no differences in the frequency of in-hospital mortality (1.3% vs 1.2%, adjusted odds ratio [aOR] 1.57, 95% CI 0.98-2.52), cardiac arrest (0.7% vs 0.9%, aOR 1.37, 95% CI 0.94-2.00), 30-day all-cause mortality (1.6% vs 1.5%, aOR 1.50, 95% CI 0.82-2.75), or 30-day all-cause postdischarge readmission (10.6% vs 10.8%, aOR 1.07, 95% CI 0.90-1.28) between cardiology telemetry ward and CCU patients. Results were similar across low-, intermediate-, and high-risk Duke Jeopardy Scores, and in patients with non-ST-segment myocardial infarction or unstable angina. CONCLUSIONS:There were no differences in clinical outcomes observed between patients with NSTE ACS initially admitted to a ward or a CCU. These findings suggest that stable NSTE ACS may be managed appropriately on telemetry wards and presents an opportunity to reduce hospital costs and critical care capacity strain.

RATIONALE/BACKGROUND:Limitations in methods for the rapid diagnosis of hospital-acquired infections often delay initiation of effective antimicrobial therapy. New diagnostic approaches offer potential clinical and cost-related improvements in the management of these infections. OBJECTIVES/OBJECTIVE:We developed a decision modeling framework to assess the potential cost-effectiveness of a rapid biomarker assay to identify hospital-acquired infection in high-risk patients earlier than standard diagnostic testing. METHODS:The framework includes parameters representing rates of infection, rates of delayed appropriate therapy, and impact of delayed therapy on mortality, along with assumptions about diagnostic test characteristics and their impact on delayed therapy and length of stay. Parameter estimates were based on contemporary, published studies and supplemented with data from a four-site, observational, clinical study. Extensive sensitivity analyses were performed. The base-case analysis assumed 17.6% of ventilated patients and 11.2% of nonventilated patients develop hospital-acquired infection and that 28.7% of patients with hospital-acquired infection experience delays in appropriate antibiotic therapy with standard care. We assumed this percentage decreased by 50% (to 14.4%) among patients with true-positive results and increased by 50% (to 43.1%) among patients with false-negative results using a hypothetical biomarker assay. Cost of testing was set at $110/d. MEASUREMENTS AND MAIN RESULTS/RESULTS:In the base-case analysis, among ventilated patients, daily diagnostic testing starting on admission reduced inpatient mortality from 12.3 to 11.9% and increased mean costs by $1,640 per patient, resulting in an incremental cost-effectiveness ratio of $21,389 per life-year saved. Among nonventilated patients, inpatient mortality decreased from 7.3 to 7.1% and costs increased by $1,381 with diagnostic testing. The resulting incremental cost-effectiveness ratio was $42,325 per life-year saved. Threshold analyses revealed the probabilities of developing hospital-acquired infection in ventilated and nonventilated patients could be as low as 8.4 and 9.8%, respectively, to maintain incremental cost-effectiveness ratios less than $50,000 per life-year saved. CONCLUSIONS:Development and use of serial diagnostic testing that reduces the proportion of patients with delays in appropriate antibiotic therapy for hospital-acquired infections could reduce inpatient mortality. The model presented here offers a cost-effectiveness framework for future test development.

PURPOSE/OBJECTIVE:Patients with acute myocardial infarction (AMI) and respiratory impairment may be treated with either invasive or non-invasive mechanical ventilation (MV). However, there has been little testing of non-invasive MV in the setting of AMI. Our objective was to evaluate the incidence and associated clinical outcomes of patients with AMI who were treated with non-invasive or invasive MV. METHODS:This was a retrospective observational study in which consecutive patients with AMI (n = 1610) were enrolled. The association between exclusively non-invasive MV, invasive MV and outcomes was assessed by multivariable models. RESULTS:Mechanical ventilation was used in 293 patients (54% invasive and 46% exclusively non-invasive). In-hospital mortality rates for patients without MV, with exclusively non-invasive MV, and with invasive MV were 4.0%, 8.8%, and 39.5%, respectively (P<0.001). The median lengths of hospital stay were 6 (5.8-6.2), 13 (11.2-4.7), and 28 (18.0-37.9) days, respectively (P<0.001). Exclusively non-invasive MV was not associated with in-hospital death (adjusted HR = 0.90, 95% CI 0.40-1.99, P = 0.79). Invasive MV was strongly associated with a higher risk of in-hospital death (adjusted HR = 3.07, 95% CI 1.79-5.26, P<0.001). CONCLUSIONS:In AMI setting, 18% of the patients required MV. Almost half of these patients were treated with exclusively non-invasive strategies with a favorable prognosis, while patients who needed to be treated invasively had a three-fold increase in the risk of death. Future prospective randomized trials are needed to compare the effectiveness of invasive and non-invasive MV for the initial approach of respiratory failure in AMI patients.