Minimally invasive thoracic left ventricular assist device implantation; case series demonstrating an integrated multidisciplinary strategy.

OBJECTIVES: The present report describes the authors' initial experience with implantation of the Heartware left ventricular assist devices (HeartWare Inc., Framingham, MA). via a minimally invasive surgical approach without cardiopulmonary bypass. A detailed overview of the anesthesiologist's role during the procedure, characteristics of the patient population, and short-term clinical outcomes are provided, and the clinical considerations that influence the decision to implant this device via an off-pump minimally invasive approach are outlined. DESIGN: Retrospective medical record review. SETTING: University hospital. PARTICIPANTS: Thirteen patients with advanced heart failure deemed candidates for off-pump minimally invasive left ventricular Heartware implantation as a bridge to heart transplantation. INTERVENTIONS: The Heartware left ventricular assist device was implanted in all 13 patients via a minimally invasive approach. MEASUREMENTS AND MAIN RESULTS: One patient required unplanned cardiopulmonary bypass to control bleeding around the left ventricular outflow cannula. The average operating room time was 249.8 minutes±46.2 minutes. Six of 13 patients required no intraoperative red blood cell transfusions. Seven patients were extubated within 12 hours after surgery. Two patients required reintubation within 48 hours. No patients required reoperation for bleeding. Average intensive care unit and hospital lengths of stay were 7.2±3.9 days and 13.4±3.6 days, respectively. There were no in-hospital deaths. CONCLUSIONS: Minimally invasive off-pump left ventricular Heartware implantation is an emerging alternative to placement by midline sternotomy. The authors speculate, based on their limited experience, that an off-pump thoracic strategy may be a desirable option for some patients and that clinical outcomes may be non-inferior to placement by midline sternotomy with cardiopulmonary bypass.

Hemodynamic transesophageal echocardiography after left ventricular assist device implantation.

OBJECTIVE: The authors hypothesized that the clinical profile of patients undergoing hTEE after continuous flow left ventricular assist device (CF-LVAD) implant would be in patients with greater acuity, more blood product utilization, and longer length of ICU stay, and that hTEE would change clinical management. DESIGN: Retrospective review. SETTING: University hospital. PARTICIPANTS: One hundred consecutive patients receiving a CF-LVAD. INTERVENTIONS: Retrospective review using a standardized electronic form of a miniaturized disposable transesophageal echocardiography probe that documented not only physical findings but also changes in hemodynamic management (hTEE) in CF-LVAD patients. MEASUREMENTS AND MAIN RESULTS: Of the 100 patients, 41 received an hTEE probe. The INTERMACS score, Leitz-Miller Score, and Kormos score indicated the hTEE group had a statistically significant greater risk of morbidity and mortality. Interoperatively, the hTEE group received more blood products and was more likely to have an open chest. Postoperatively, the hTEE group received more blood products, had a longer total length of stay, and had increased mortality. ICU length of stay, days on inotropes and days on mechanical ventilation were not statistically significant between the 2 groups. Information obtained from hTEE changed ICU management in 72% of studies. CONCLUSION: Retrospective review of CF-LVAD patients revealed that postoperative hTEE is used in sicker CF-LVAD patients and frequently leads to changes in ICU clinical management.

Implementing goal-directed protocols reduces length of stay after cardiac surgery.

OBJECTIVE: To test the effect of a high reliability organization (HRO) intervention on patient lengths of stay in the CVICU and hospital. The authors proposed that (1) higher safety related evidence based protocol (SREBP) team compliance scores and (2) lower SREBP milestone scores are associated with shorter lengths of CVICU and hospital stay. DESIGN: A prospective, longitudinal observational evaluation was used to assess the effects of SREBP-focused rounding processes and a milestone-tracking tool. SETTING: United States, university academic medical center's 27-bed CVICU. PARTICIPANTS: Six hundred sixty-five adult cardiac surgery patients and the CVICU care team (100 registered nurses and 16 clinical providers) participated. MEASUREMENTS AND MAIN RESULTS: Team compliance was the proportion of SREBP-related team behaviors exhibited during daily rounds. Patients' milestone scores were the cumulative difference between actual and expected times for 4 SREBP milestones over 48 hours. Milestones achieved earlier than expected indicated reduced complication risk, and milestones achieved later than expected indicated increased risk. As team compliance increased, CVICU length of stay decreased 0.66 (95% CI: -0.04 to 1.28; p = 0.08) days; hospital stay decreased 0.89 times (95% CI: 0.77-1.03; p = 0.008). As the mean milestone scores increased from -7 to 12, length of ICU stay increased 2.63 (95% CI: 1.66-3.59; p<0.001) days; hospital length of stay increased 1.44 times (95% CI: 1.23-1.7; p = 0.05). CONCLUSIONS: A milestone-driven pathway supported by team rounding was associated with decreased lengths of CVICU and hospital stay. However, tracking patient trajectories by milestones suggests a more complex relationship than anticipated and presents new opportunities for SREBP implementation and research.

Etomidate use and postoperative outcomes among cardiac surgery patients.

BACKGROUND: Although a single dose of etomidate can cause relative adrenal insufficiency, the impact of etomidate exposure on postoperative outcomes is unknown. The objective of this study was to examine the association between a single induction dose of etomidate and clinically important postoperative outcomes after cardiac surgery. METHODS: The authors retrospectively examined the association between etomidate exposure during induction of anesthesia and postoperative outcomes in patients undergoing cardiac surgery from January 2007 to December 2009 by using multivariate logistic regression analyses and Cox proportional hazards regression analyses. Postoperative outcomes of interest were severe hypotension, mechanical ventilation hours, hospital length of stay, and in-hospital mortality. RESULTS: Sixty-two percent of 3,127 patients received etomidate. Etomidate recipients had a higher incidence of preoperative congestive heart failure (23.0 vs. 18.3%; P = 0.002) and a lower incidence of preoperative cardiogenic shock (1.3 vs. 4.0%; P < 0.001). The adjusted odds ratio for severe hypotension and in-hospital mortality associated with receiving etomidate was 0.80 (95% CI, 0.58-1.09) and 0.75 (95% CI, 0.45-1.24), respectively, and the adjusted hazard ratio for time to mechanical ventilation removal and time to hospital discharge was 1.10 (95% CI, 1.00-1.21) and 1.07 (95% CI, 0.97-1.18), respectively. Propensity score analysis did not change the association between etomidate use and postoperative outcomes. CONCLUSIONS: In this study, there was no evidence to suggest that etomidate exposure was associated with severe hypotension, longer mechanical ventilation hours, longer length of hospital stay, or in-hospital mortality. Etomidate should remain an option for induction of anesthesia in cardiac surgery patients.

Early bispectral index and sedation requirements during therapeutic hypothermia predict neurologic recovery following cardiac arrest.

OBJECTIVES: To test the hypothesis that low bispectral index scores and low sedative requirements during therapeutic hypothermia predict poor neurologic outcome. DESIGN: Observational study of a prospectively collected cohort. SETTING: Cardiovascular ICU. PATIENTS: One hundred sixty consecutive cardiac arrest patients treated with therapeutic hypothermia. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Eighty-four of the 141 subjects (60%) who survived hypothermia induction were discharged from the ICU with poor neurologic outcome, defined as a cerebral performance category score of 3, 4, or 5. These subjects had lower bispectral index (p < 0.001) and sedative requirements (p < 0.001) during hypothermia compared with the 57 subjects discharged with good outcome. Early prediction of neurologic recovery was best 7 hours after ICU admission, and median bispectral index scores at that time were 31 points lower in subjects discharged with poor outcome (11 [interquartile range, 4-29] vs 42 [37-49], p < 0.001). Median sedation requirements decreased by 17% (interquartile range, -50 to 0%) 7 hours after ICU admission in subjects with poor outcome but increased by 50% (interquartile range, 0-142%) in subjects with good outcome (p < 0.001). Each 10-point decrease in bispectral index was independently associated with a 59% increase in the odds of poor outcome (95% CI, 32-76%; p < 0.001). The model including bispectral index and sedative requirement correctly reclassified 15% of subjects from good to poor outcome and 1% of subjects from poor to good outcome. The model incorrectly reclassified 1% of subjects from poor to good outcome but did not incorrectly reclassify any from good to poor outcome. CONCLUSIONS: Bispectral index scores and sedative requirements early in the course of therapeutic hypothermia improve the identification of patients who will not recover from brain anoxia. The ability to accurately predict nonrecovery after cardiac arrest could facilitate discussions with families, reduce patient suffering, and limit use of ICU resources in futile cases.

Comparison of expert and novice performance of a simulated transesophageal echocardiography examination.

INTRODUCTION: Training in transesophageal echocardiography (TEE) requires a significant commitment of time and resources on behalf of the trainees and the instructors. Training opportunities may be limited in the busy clinical environment. Medical simulation has emerged as a complementary means by which to develop clinical skills. Transesophageal echocardiography simulators have been commercially available for several years, yet their ability to distinguish experts from novices has not been demonstrated. We used a standardized assessment tool to distinguish experts from novices using a commercially available TEE simulator. METHODS: Anesthesiologists certified in advanced perioperative TEE and anesthesiology resident physicians were recruited into the expert and novice cohorts, respectively. The cohorts were recruited from 2 academic medical centers. The novice cohort received a structured introduction to the basic TEE examination. Both cohorts then proceeded to perform a basic TEE examination involving normal cardiac anatomy, which was evaluated by blinded raters using a standardized assessment tool. RESULTS: The expert cohort consistently demonstrated the ability to obtain standard TEE imaging views in less time and more accurately than the novice cohort during the course of a simulated TEE examination. CONCLUSIONS: A simulated transesophageal examination of normal cardiac anatomy in concert with a standardized assessment tool permits ample discrimination between expert and novice echocardiographers as defined for this investigation. Future research will examine in detail the role echocardiography simulators should play during echocardiography training including assessment of training level.

Episodic monoplane transesophageal echocardiography impacts postoperative management of the cardiac surgery patient.

OBJECTIVE: A new slender, flexible, and miniaturized disposable monoplane transesophageal TEE probe has been approved for episodic hemodynamic transesophageal echocardiographic monitoring. The authors hypothesized that episodic monoplane TEE with a limited examination would help guide the postoperative management of high-risk cardiac surgery patients. DESIGN: The authors analyzed the initial consecutive observational experience with the miniaturized transesophageal echocardiography monitoring system (ClariTEE, ImaCor, Uniondale, New York). SETTING: Single institution in a university setting. PARTICIPANTS: Unstable cardiac surgery patients. INTERVENTIONS: The authors assessed fluid responsiveness, echocardiographic data, and concordance among hemodynamic data. MEASUREMENTS AND MAIN RESULTS: From June 2010 to February 2011, 21 unstable cardiac surgery patients with postoperative instability were identified. Two patients (10%) required reoperation for bleeding and tamponade physiology. Right ventricular dysfunction was diagnosed by episodic TEE monitoring in 7 patients (33%), while hypovolemia was documented in 12 patients (57%). Volume responsiveness was documented in 11 patients. In this observational study, discordance between hemodynamic monitoring and episodic TEE was qualitatively observed in 14 patients (66%). CONCLUSION: The authors demonstrated the ability of episodic monoplane TEE to identify discordance between hemodynamic monitoring to better define clinical scenarios in unstable cardiac surgery patients. For these challenging patients, limited episodic TEE assessment has become a cornerstone of ICU care in this institution.

Delirium in the cardiovascular ICU: exploring modifiable risk factors.

OBJECTIVE: Delirium, an acute organ dysfunction, is common among critically ill patients leading to significant morbidity and mortality; its epidemiology in a mixed cardiology and cardiac surgery ICU is not well established. We sought to determine the prevalence and risk factors for delirium among cardiac surgery ICU patients. DESIGN: Prospective observational study. SETTING: Twenty-seven-bed medical-surgical cardiac surgery ICU. PATIENTS: Two hundred consecutive patients with an expected cardiac surgery ICU length of stay >24 hrs. INTERVENTIONS: None. MEASUREMENTS: Baseline demographic data and daily assessments for delirium using the validated and reliable Confusion Assessment Method for the ICU were recorded, and quantitative tracking of delirium risk factors were conducted. Separate analyses studied the role of admission risk factors for occurrence of delirium during the cardiac surgery ICU stay and identified daily occurring risk factors for the development of delirium on a subsequent cardiac surgery ICU day. MAIN RESULTS: Prevalence of delirium was 26%, similar among cardiology and cardiac surgical patients. Nearly all (92%) exhibited the hypoactive subtype of delirium. Benzodiazepine use at admission was independently predictive of a three-fold increased risk of delirium (odds ratio 3.1 [1, 9.4], p = 0.04) during the cardiac surgery ICU stay. Of the daily occurring risk factors, patients who received benzodiazepines (2.6 [1.2, 5.7], p = 0.02) or had restraints or devices that precluded mobilization (2.9 [1.3, 6.5], p < 0.01) were more likely to have delirium the following day. Hemodynamic status was not associated with delirium. CONCLUSIONS: Delirium occurred in one in four patients in the cardiac surgery ICU and was predominately hypoactive in subtype. Chemical restraints via use of benzodiazepines or the use of physical restraints/restraining devices predisposed patients to a greater risk of delirium, pointing to areas of quality improvement that would be new to the vast majority of cardiac surgery ICUs.

Implementation of a standardized pathway for the treatment of cardiac arrest patients using therapeutic hypothermia: "CODE ICE".

Out-of-hospital cardiac arrest is common and is associated with high mortality. The majority of in-hospital deaths from resuscitated victims of cardiac arrest are due to neurologic injury. Therapeutic hypothermia (TH) is now recommended for the management of comatose survivors of cardiac arrest. The rapid triage and standardized treatment of cardiac arrest patients can be challenging, and implementation of a TH program requires a multidisciplinary team approach. In 2010, we revised our institution's TH protocol, creating a "CODE ICE" pathway to improve the timely and coordinated care of cardiac arrest patients. As part of CODE ICE, we implemented comprehensive care pathways including measures such as a burst paging system and computerized physician support tools. "STEMI on ICE" integrates TH with our regional ST-elevation myocardial infarction network. Retrospective data were collected on 150 consecutive comatose cardiac arrest victims treated with TH (n = 82 pre-CODE ICE and n = 68 post-CODE ICE) from 2007 to 2011. After implementation of CODE ICE, the mean time to initiation of TH decreased from 306 ± 165 minutes to 196 ± 144 minutes (P < 0.001), and the time to target temperature decreased from 532 ± 214 minutes to 392 ± 215 minutes (P < 0.001). There was no significant change in survival or neurologic outcome at hospital discharge. Through the implementation of CODE ICE, we were able to reduce the time to initiation of TH and time to reach target temperature. Additional studies are needed to determine the effect of CODE ICE and similar pathways on clinical outcomes after cardiac arrest.