Sustainability of the Subspecialty of Anesthesiology Critical Care: An Expert Consensus and Review of the Literature.

While considerable literature exists with respect to clinical aspects of critical care anesthesiology (CCA) practice, few publications have focused on how anesthesiology-based critical care practices are organized and the challenges associated with the administration and management of anesthesiology critical care units. Currently, numerous challenges are affecting the sustainability of CCA practice, including decreased applications to fellowship positions and decreased reimbursement for critical care work. This review describes what is known about the subspecialty of CCA and leverages the experience of administrative leaders in adult critical care anesthesiologists in the United States to describe potential solutions.

A Review and Discussion of Full-Time Equivalency and Appropriate Compensation Models for an Adult Intensivist in the United States Across Various Base Specialties.

OBJECTIVES: Physicians with training in anesthesiology, emergency medicine, internal medicine, neurology, and surgery may gain board certification in critical care medicine upon completion of fellowship training. These clinicians often only spend a portion of their work effort in the ICU. Other work efforts that benefit an ICU infrastructure, but do not provide billing opportunities, include education, research, and administrative duties. For employed or contracted physicians, there is no singular definition of what constitutes an intensive care full-time equivalent (FTE). Nevertheless, hospitals often consider FTEs in assessing hiring needs, salary, and eligibility for benefits. DATA SOURCES: Review of existing literature, expert opinion. STUDY SELECTION: Not applicable. DATA EXTRACTION: Not applicable. DATA SYNTHESIS: Not applicable. CONCLUSIONS: Understanding how an FTE is calculated, and the fraction of an FTE to be assigned to a particular cost center, is therefore important for intensivists of different specialties, as many employment models assign salary and benefits to a base specialty department and not necessarily the ICU.

The Association of the Pulmonary Artery Pulsatility Index and Right Ventricular Function after Cardiac Surgery.

Background: The pulmonary artery pulsatility index (PAPi) has been shown to correlate with right ventricular (RV) failure in patients with cardiac disease. However, the association of PAPi with right ventricular function following cardiac surgery is not yet established. Methods: PAPi and other hemodynamic variables were obtained postoperatively for 959 adult patients undergoing cardiac surgery. The association of post-bypass right ventricular function and other clinical factors to PAPi was evaluated using linear regression. A propensity-score matched cohort for PAPi ≥ 2.00 was used to assess the association of PAPi with postoperative outcomes. Results: 156 patients (16.3%) had post-bypass right ventricular dysfunction defined by visualization on transesophageal echocardiography. There was no difference in postoperative PAPi based on right ventricular function (2.12 vs. 2.00, p=0.21). In our matched cohort (n = 636), PAPi < 2.00 was associated with increased incidence of acute kidney injury (23.0% vs 13.2%, p < 0.01) and ventilator time (6.0 hours vs 5.6 hours, p=0.04) but not with 30-day mortality or intensive care unit length of stay. Conclusion: In a general cohort of patients undergoing cardiac surgery, postoperative PAPi was not associated with postcardiopulmonary bypass right ventricular dysfunction. A postoperative PAPi < 2 may be associated with acute kidney injury.

Postoperative Pulmonary Artery Pulsatility Index Improves Prediction of Right Ventricular Failure After Left Ventricular Assist Device Implantation.

OBJECTIVES: This study evaluated whether the postoperative pulmonary artery pulsatility index (PAPi) is associated with postoperative right ventricular dysfunction after durable left ventricular assist device (LVAD) implantation. DESIGN: Single-center retrospective observational cohort study. SETTING: The University of Kansas Medical Center, a tertiary-care academic medical center. PARTICIPANTS: Sixty-seven adult patients who underwent durable LVAD implantation between 2017 and 2019. INTERVENTIONS: All patients underwent open cardiac surgery with cardiopulmonary bypass under general anesthesia with pulmonary artery catheter insertion. MEASUREMENTS AND MAIN RESULTS: Clinical and hemodynamic data were collected before and after surgery. The Michigan right ventricular failure risk score and the European Registry for Patients with Mechanical Circulatory Support score were calculated for each patient. The primary outcome was right ventricular failure, defined as a composite of right ventricular mechanical circulatory support, inhaled pulmonary vasodilator therapy for 48 hours or greater, or inotrope use for 14 days or greater or at discharge. Thirty percent of this cohort (n = 20) met the primary outcome. Preoperative transpulmonary gradient (odds ratio [OR] 1.15, 95% CI 1.02-1.28), cardiac index (OR 0.83, 95% CI 0.71-0.98), and postoperative PAPi (OR 0.85, 95% CI 0.75-0.97) were the only hemodynamic variables associated with the primary outcome. The addition of postoperative PAPi was associated with improvement in the predictive model performance of the Michigan score (area under the receiver operating characteristic curve 0.73 v 0.56, p = 0.03). An optimal cutoff point for postoperative PAPi of 1.56 was found. CONCLUSIONS: The inclusion of postoperative PAPi offers more robust predictive power for right ventricular failure in patients undergoing durable LVAD implantation, compared with the use of existing risk scores alone.

Prospective Evaluation of a Multibeat Analysis Cardiac Index Estimation in Patients With Cardiogenic Shock.

OBJECTIVES: The decision algorithm for managing patients in cardiogenic shock depends on cardiac index (CI) estimates. Cardiac index estimation via thermodilution (CI-TD) using a pulmonary artery catheter is used commonly for obtaining CI in these patients. Minimally invasive methods of estimating CI, such as multibeat analysis (CI-MBA), may be an alternative in this population. DESIGN: A prospective, observational study. SETTING: Cardiac intensive care unit. PARTICIPANTS: Twenty-two subjects in cardiogenic shock provided 101 paired CI measurements. INTERVENTIONS: Measurements were obtained concomitantly by intermittent CI-TD and CI-MBA (Argos Cardiac Output Monitor; Retia Medical, Valhalla, NY). For each CI-TD, CI-MBA estimates were averaged over 1 minute to provide paired values. Bland-Altman and 4-quadrant analyses were performed by plotting changes between successive CI measurements (ΔCI) from each of the 2 methods. Concordance was calculated as a percentage using ΔCI data points from the 2 methods, outside an exclusion zone of 15%. MEASUREMENTS AND MAIN RESULTS: The correlation coefficient between CI-MBA and CI-TD was 0.78 across patients. Mean CI-TD was 2.19 ± 0.46 L/min/m2 and mean CI-MBA was 2.38 ± 0.59 L/min/m2. The mean difference between CI-MBA and CI-TD (bias ± SD) was 0.20 ± 0.47 L/min/m2, and the limits of agreement were -0.72 to 1.11 L/min/m2. The percentage error was 40.0%. The concordance rate was 94%. A secondary analysis of a subgroup of patients during periods of arrhythmia demonstrated a similar accuracy of performance of CI-MBA. CONCLUSIONS: Cardiac index-MBA is not interchangeable with CI-TD. However, CI-MBA provides reasonable correlation and clinically acceptable trending ability compared with CI-TD. Cardiac output-MBA may be useful in trending changes in CI in patients with cardiogenic shock, especially in those whose pulmonary artery catheterization placement carries a high risk or is unobtainable.

Comparing the associations of central venous pressure and pulmonary artery pulsatility index with postoperative renal injury.

Objective: Cardiac surgery-associated acute kidney injury (CS-AKI) is associated with significant morbidity and mortality. We investigated the association of postoperative central venous pressure (CVP) and pulmonary artery pulsatility index (PAPi) with the development of CS-AKI. Methods: This was a single-center, retrospective cohort study of patients undergoing cardiac surgery. CVP and PAPi were acquired hourly postoperatively and averaged for up to 48 h. PAPi was calculated as [(Pulmonary Artery Systolic Pressure-Pulmonary Artery Diastolic Pressure) / CVP]. The primary aim was CS-AKI. Secondary aims were need for renal replacement therapy (RRT), hospital and 30-day mortality, total ventilator and intensive care unit hours, and hospital length of stay. Logistic regression was used to calculate odds of development of renal injury and need for RRT. Results: One thousand two hundred eighty-eight patients were included. The average postoperative CVP was 10.3 mmHg and average postoperative PAPi was 2.01. Patients who developed CS-AKI (n = 384) had lower PAPi (1.79 vs. 2.11, p < 0.01) and higher CVP (11.5 vs. 9.7 mmHg, p < 0.01) than those who did not. Lower PAPi and higher CVP were also associated with each secondary aim. A standardized unit decrease in PAPi was associated with increased odds of CS-AKI (OR 1.39, p < 0.01) while each unit increase in CVP was associated with both increased odds of CS-AKI (OR 1.56, p < 0.01) and postoperative RRT (OR 1.49, p = 0.02). Conclusions: Both lower PAPi and higher CVP values postoperatively were associated with the development of CS-AKI but only higher CVP was associated with postoperative RRT use. When differences in values are standardized, CVP may be more associated with development of CS-AKI when compared to PAPi.

Impact of Early, Low-Dose Factor VIIa on Subsequent Transfusions and Length of Stay in Cardiac Surgery.

OBJECTIVE: Recombinant factor VII (rFVIIa) is used to treat cardiac surgical bleeding in an off-label manner. However, optimal dosing and timing of administration to provide efficacious yet safe outcomes remain unknown. DESIGN: Retrospective, observational study. SETTING: Tertiary care academic center. PARTICIPANTS: Cardiac surgical patients (N = 214) who received low-dose rFVIIa for cardiac surgical bleeding. INTERVENTIONS: Patients were allocated into one of three groups based on timing of rFVIIa administration during the course of bleeding resuscitation based on the number of hemostatic products given before rFVIIa administration: group one = ≤one products (n = 82); group two = two-to-four products (n = 73); and group three= ≥five products (n = 59). MEASUREMENTS AND MAIN RESULTS: Patients who received low-dose rFVIIa later in the course of bleeding resuscitation (group three) had longer intensive care unit stays (p = 0.014) and increased incidence of postoperative renal failure when compared with group one (p = 0.039). Total transfusions were lowest in patients who received rFVIIa early in the course of resuscitation (group one) (median, two [interquartile range (IQR), 1-4.75]) and highest in group three (median, 11 [IQR, 8-14]; p < 0.001). Subsequent blood product transfusions after rFVIIa administration were highest in group two (p = 0.003); however, the median for all three groups was two products. There were no differences in thrombosis, reexplorations, or mortality in any of the groups. CONCLUSIONS: This study identified no differences in adverse outcomes based on timing of administration of low-dose rFVIIa for cardiac surgical bleeding defined by stage of resuscitation, but the benefits of early administration remain unclear.

Very low-dose recombinant Factor VIIa administration for cardiac surgical bleeding reduces red blood cell transfusions and renal risk: a matched cohort study.

Outcomes following administration of very-low-dose recombinant activated factor VIIa (vld-rFVIIa) for cardiac surgical bleeding remain debatable. We sought to determine the association of vld-rFVIIa and adverse surgical outcomes. Retrospective, cohort matching of patients undergoing cardiac surgery who received vld-rFVIIa (median 13.02 µg/kg) for perioperative bleeding were matched to cardiac surgical patients who had bleeding and received standard of care for bleeding without Factor VIIa administration. Of the 362 matched patients (182 in each group), patients who received rFVIIa required significantly less red blood cell transfusions [median 3 units (range 0--60, IQR = 4 units) versus 4 units (range 2-34, IQR = 4 units); P = 0.0004], decreased length of hospital stay (median 8 versus 9 days; P = 0.0158) and decreased renal risk (P < 0.0001). Incidence of renal failure, postoperative infection, postoperative thrombosis, prolonged ventilation, total ICU hours and 30-day mortality were not different between the two groups. Vld-rFVIIa for cardiac surgical bleeding was associated with decreased red blood cell transfusion, renal risk and length of hospital stay without increased thromboembolism or mortality when compared to patients who had cardiac surgical bleeding and received standard of care without Factor VIIa.

Molecular Cardioprotection and the Role of Exosomes: The Future Is Not Far Away.

Heart disease is the leading cause of death in men and women in the United States. During the past several decades, research into the role of specific intracellular mediators, called exosomes, has advanced the understanding of molecular cardioprotection. Exosomes and the micro-RNAs within them may be potential targets for the development of genetically engineered or biosimilar medications for patients in heart failure or with ischemic cardiac disease. This review discusses anesthetic implications of exosome production and the future micro-RNA applications for cardioprotection.