Diagnosis and Management of Vasoplegia in Temporary Mechanical Circulatory Support: A Narrative Review.

Refractory vasodilatory shock, or vasoplegia, is a pathophysiologic state observed in the intensive care unit and operating room in patients with a variety of primary diagnoses. Definitions of vasoplegia vary by source but are qualitatively defined clinically as a normal or high cardiac index and low systemic vascular resistance causing hypotension despite high-dose vasopressors in the setting of euvolemia. This definition can be difficult to apply to patients undergoing mechanical circulatory support (MCS). A large body of mostly retrospective literature exists on vasoplegia in the non-MCS population, but the increased use of temporary MCS justifies an examination of vasoplegia in this population. MCS, particularly extracorporeal membrane oxygenation, adds complexity to the diagnosis and management of vasoplegia due to challenges in determining cardiac output (or total blood flow), lack of clarity on appropriate dosing of noncatecholamine interventions, increased thrombosis risk, the difficulty in determining the endpoints of adequate volume resuscitation, and the unclear effects of rescue agents (methylene blue, hydroxocobalamin, and angiotensin II) on MCS device monitoring and function. Care teams must combine data from invasive and noninvasive sources to diagnose vasoplegia in this population. In this narrative review, the available literature is surveyed to provide guidance on the diagnosis and management of vasoplegia in the temporary MCS population, with a focus on noncatecholamine treatments and special considerations for patients supported by extracorporeal membrane oxygenation, transvalvular heart pumps, and other ventricular assist devices.

Impact of Pressure Recovery Adjustment on Aortic Valve Area Classification of Disease Severity in Transcatheter Aortic Valve Replacement Patients.

OBJECTIVES: To determine the impact of pressure recovery (PR) adjustment on disease severity grading in patients with severe aortic stenosis. The authors hypothesized that accounting for PR would result in echocardiographic reclassification of aortic stenosis severity in a significant number of patients. DESIGN: A retrospective observational study between October 2013 and February 2021. SETTING: A single-center, quaternary-care academic center. PARTICIPANTS: Adults (≥18 years old) who underwent transcatheter aortic valve implantation (TAVI). INTERVENTIONS: TAVI. MEASUREMENTS AND MAIN RESULTS: A total of 342 patients were evaluated in this study. Left ventricle mass index was significantly greater in patients who continued to be severe after PR (100.47 ± 28.77 v 90.15 ± 24.03, p = < 0.000001). Using PR-adjusted aortic valve area (AVA) resulted in the reclassification of 81 patients (24%) from severe to moderate aortic stenosis (AVA >1.0 cm2). Of the 81 patients who were reclassified, 23 patients (28%) had sinotubular junction (STJ) diameters >3.0 cm. CONCLUSION: Adjusting calculated AVA for PR resulted in a reclassification of a significant number of adult patients from severe to moderate aortic stenosis. PR was significantly larger in patients who reclassified from severe to moderate aortic stenosis after adjusting for PR. PR appeared to remain relevant in patients with STJ ≥3.0 cm. Clinicians need to be aware of PR and how to account for its effect when measuring pressure gradients with Doppler.

Obesity and Extracorporeal Membrane Oxygenation (ECMO): Analysis of Outcomes.

Traditionally, patients with obesity have been deemed ineligible for extracorporeal life support (ELS) therapies such as extracorporeal membrane oxygenation (ECMO), given the association of obesity with chronic health conditions that contribute to increased morbidity and mortality. Nevertheless, a growing body of literature suggests the feasibility, efficacy, and safety of ECMO in the obese population. This review provides an in-depth analysis of the current literature assessing the effects of obesity on outcomes among patients supported with ECMO (venovenous [VV] ECMO in noncoronavirus disease 2019 and coronavirus disease 2019 acute respiratory distress syndrome, venoarterial [VA] ECMO, and combined VV and VA ECMO), offer a possible explanation of the current findings on the basis of the obesity paradox phenomenon, provides a framework for future studies addressing the use of ELS therapies in the obese patient population, and provides guidance from the literature for many of the challenges related to initiating, maintaining, and weaning ELS therapy in patients with obesity.

Should Obesity Be an Exclusion Criterion for Extracorporeal Membrane Oxygenation Support? A Scoping Review.

Obesity is often considered a contraindication to extracorporeal membrane oxygenation (ECMO) candidacy due to technical challenges with vascular access, higher cardiac output requirements, and known associations between obesity and overall increased morbidity and mortality due to chronic health conditions. However, a growing body of literature suggests that ECMO may be as safe and efficacious in both obese and nonobese patients. This scoping review provides a synthesis of the available literature on the outcomes of obese patients supported with (1) venovenous (VV)-ECMO in acute respiratory distress syndrome (ARDS) not due to coronavirus disease 2019 (COVID-19), (2) VV-ECMO in ARDS due to COVID-19, (3) venoarterial (VA)-ECMO for all indications, and (4) studies combining data of patients supported with VA- and VV-ECMO. A librarian-assisted search was performed using 4 primary electronic medical databases (PubMed, Web of Science, Excerpta Medica database [Embase], and Cochrane Library) from January 2003 to March 2023. Articles that reported outcomes of obese patients requiring ECMO support were included. Two reviewers independently screened titles, abstracts, and full text of articles to determine eligibility. Data extraction was performed using customized fields established a priori within a systematic review software system. A total of 354 publications were imported for screening on titles and abstracts, and 30 studies were selected for full-text review. A total of 26 publications met the inclusion criteria: 7 on VV-ECMO support in non-COVID-19 ARDS patients, 6 on ECMO in COVID-19 ARDS patients, 8 in patients supported with VA-ECMO, and 5 combining both VA- and VV-ECMO data. Although the included studies are limited to retrospective analyses and display a heterogeneity in definitions of obesity and comparison groups, the currently available literature suggests that outcomes and complications of ECMO therapy are equivalent in obese patients as compared to nonobese patients. Hence, obesity as measured by body mass index alone should not be considered an exclusion criterion in the decision to initiate ECMO.

Anesthesia for cesarean delivery in a patient with congenitally corrected transposition of the great arteries: A case report.

Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease often associated with other cardiac defects. The adaptations and physiologic changes in pregnancy can present maternal challenges and complications; multidisciplinary care allows for the safest management of pregnancy and delivery in these patients. We present a case of the anesthetic management of cesarean delivery in a woman with CCTGA with her pregnancy complicated by recurrent volume overload, pulmonary hypertension, and dysrhythmias.

ABO Blood Group and Bleeding and Survival in VA-ECMO Patients.

ABO blood group has been shown to be a major determinant of plasma von Willebrand factor (vWF) levels. O blood group is associated with the lowest vWF levels and confers an increased risk of hemorrhagic events, while AB blood group has the highest levels and is associated with thromboembolic events. We hypothesized in extracorporeal membrane oxygenation (ECMO) patients that O blood type would have the highest and AB blood type would have the lowest transfusions, with an inverse relationship to survival. A retrospective analysis of 307 VA-ECMO patients at a major quaternary referral hospital was performed. The distribution of blood groups included 124 group O (40%), 122 group A (40%), 44 group B (14%), and 17 group AB (6%) patients. Regarding usage of packed red blood cells, fresh frozen plasma, and platelets, there was a non-statistically significant difference in transfusions, with group O having the least and group AB having the most requirements. However, there was a statistically significant difference in cryoprecipitate usage when comparing to group O: group A (1.77, 95% CI: 1.05-2.97, P < .05), group B (2.05, 95% CI: 1.16-3.63, P < .05), and group AB (3.43, 95% CI: 1.71-6.90, P < .001). Furthermore, a 20% increase in length of days on ECMO was associated with a 2-12% increase in blood product usage. The cumulative 30-day mortality rate for groups O and A was 60%, group B was 50%, and group AB was 40%; the 1-year mortality rate for groups O and A was 65%, group B was 57%, and group AB was 41%; however, the mortality differences were not statistically significant.

Red blood cell distribution width predicts mortality of adult patients receiving veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Red blood cell distribution width (RDW) is a numerical measure of the variation in the size of circulating red blood cells. Recently, there is increasing interest in the role of RDW as a biomarker for inflammatory states and as a prognostication tool for a wide range of clinical manifestations. The predictive power of RDW on mortality among patients receiving mechanical circulatory support remains largely unknown. METHODS: A retrospective analysis of 281 VA-ECMO patients at a tertiary referral academic hospital from 2009 to 2019 was performed. RDW was dichotomized with RDW-Low <14.5% and RDW-High ≥14.5%. The primary outcome was all-cause mortality at 30 days and 1 year. Cox proportional hazards models were used to examine the association between RDW and the clinical outcomes after adjusting for additional confounders. RESULTS: 281 patients were included in the analysis. There were 121 patients (43%) in the RDW-Low group and 160 patients (57%) in the RDW-High group. Survival to ECMO decannulation [RDW-H: 58% versus RDW-L: 67%, p = 0.07] were similar between the two groups. Patients in RDW-H group had higher 30-days mortality (RDW-H: 67.5% vs RDW-L: 39.7%, p < 0.001) and 1 year mortality (RDW-H: 79.4% vs RDW-L: 52.9%, p < 0.001) compared to patients in the RDW-L group. After adjusting for confounders, Cox proportional hazards model demonstrated that patients with high RDW had increased odds of mortality at 30 days (hazard ratio 1.9, 95% CI 1.2-3.0, p < 0.01) and 1 year (hazard ratio 1.9, 95% CI 1.3-2.8, p < 0.01) compared to patients with low RDW. CONCLUSIONS: Among patients receiving mechanical circulatory support with VA-ECMO, a higher RDW was independently associated with increased 30-days and 1-year mortality. RDW may serve as a simple biomarker that can be quickly obtained to help provide risk stratification and predict survival for patients receiving VA-ECMO.

Preoperative Pulmonary Artery-to-Aorta Diameter Ratio as a Predictor of Postoperative Severe Right Ventricular Failure and 1-Year Mortality After Left Ventricular Assist Device Implantation.

OBJECTIVES: To evaluate the association of pulmonary artery diameter and pulmonary artery- to-aorta diameter ratio (PA/Ao) with right ventricular failure and mortality within 1 year after left ventricular assist device implantation. DESIGN: This was a retrospective observational study between March 2013 and July 2019. SETTING: The study was conducted at a single, quaternary-care academic center. PARTICIPANTS: Adults (≥18 years old) receiving a durable left ventricular assist device (LVAD). Inclusion if (1) a chest computed tomography scan was performed within 30 days before the LVAD and (2) a right and left heart catheterization was completed within 30 days before the LVAD. INTERVENTIONS: A left ventricular assist device was used for intervention. MEASUREMENTS AND MAIN RESULTS: A total of 176 patients were included in this study. Median PA diameter and PA/Ao ratio were significantly greater in the severe right ventricular failure (RVF) group (p = 0.001, p < 0.001, respectively). Receiver operating characteristic analysis revealed PA/Ao and RVF as predictors for mortality (area under the curve = 0.725 and 0.933, respectively). Logistic regression analysis-predicted probability gave a PA/Ao ratio cutoff point of 1.04 (p < 0.001). Survival probability was significantly worse in patients with a PA/Ao ratio ≥1.04 (p = 0.005). CONCLUSIONS: The PA/Ao ratio is an easily measurable noninvasive indicator that can predict RVF and 1-year mortality after LVAD implantation.

A rare case of echo enhancing agent anaphylaxis complicated by acute coronary syndrome.

Enhancing agents in echocardiography are used frequently to improve endocardial border visualization and assessment of structural heart disease. We present a unique case of anaphylactic shock with acute coronary syndrome following administration of sulfur hexafluoride echo enhancing agent. This case emphasizes the importance of recognizing anaphylaxis to enhancing agents, as well as recognizing the potential relationship between anaphylaxis and acute coronary syndrome with in-stent thrombosis.