Prognosis of Venoarterial Extracorporeal Membrane Oxygenation in Mixed, Cardiogenic and Septic Shock

Mixed Shock Complicating Cardiogenic Shock: Frequency, Predictors, and Clinical Outcomes

BACKGROUND

Patients presenting with cardiogenic shock (CS) are at risk of developing mixed shock (MS), characterized by distributive-inflammatory phenotype. However, no objective definition exists for this clinical entity.

METHODS

We assessed the frequency, predictors, and prognostic relevance of MS complicating CS, based on a newly proposed objective definition. MS complicating CS was defined as an objective shock state secondary to both an ongoing cardiogenic cause and a distributive-inflammatory phenotype arising at least 12 hours after the initial CS diagnosis, as substantiated by predefined longitudinal changes in hemodynamics, clinical, and laboratory parameters.

RESULTS

Among 213 consecutive patients admitted at 2 cardiac intensive care units with CS, 13 with inflammatory-distributive features at initial presentation were excluded, leading to a cohort of 200 patients hospitalized with pure CS (67±13 years, 96% Society of Cardiovascular Angiography and Interventions CS stage class C or higher). MS complicating CS occurred in 24.5% after 120 (29-216) hours from CS diagnosis. Lower systolic arterial pressure (P=0.043), hepatic injury (P=0.049), and suspected/definite infection (P=0.013) at CS diagnosis were independent predictors of MS development. In-hospital mortality (53.1% versus 27.8%; P=0.002) and hospital stay (21 [13-48] versus 17 [9-27] days; P=0.018) were higher in the MS cohort. At logistic multivariable analysis, MS diagnosis (odds ratio [OR], 3.00 [95% CI, 1.39-6.63]; Padj=0.006), age (OR, 1.06 [95% CI, 1.03-1.10] years; Padj<0.001), admission systolic arterial pressure <100 mm Hg (OR, 2.41 [95% CI, 1.19-4.98]; Padj=0.016), and admission serum creatinine (OR, 1.61 [95% CI, 1.19-2.26]; Padj=0.003) conferred higher odds of in-hospital death, while early temporary mechanical circulatory support was associated with lower in-hospital death (OR, 0.36 [95% CI, 0.17-0.75]; Padj=0.008).

CONCLUSIONS

MS complicating CS, objectively defined leveraging on longitudinal changes in distributive and inflammatory features, occurs in one-fourth of patients with CS, is predicted by markers of CS severity and inflammation at CS diagnosis, and portends higher hospital mortality.

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.

Extracorporeal membrane oxygenation in adult patients with sepsis and septic shock: Why, how, when, and for whom

Sepsis and septic shock remain the leading causes of death in intensive care units. Some patients with sepsis fail to respond to routine treatment and rapidly progress to refractory respiratory and circulatory failure, necessitating extracorporeal membrane oxygenation (ECMO). However, the role of ECMO in adult patients with sepsis has not been fully established. According to existing studies, ECMO may be a viable salvage therapy in carefully selected adult patients with sepsis. The choice of venovenous, venoarterial, or hybrid ECMO modes is primarily determined by the patient's oxygenation and hemodynamics (distributive shock with preserved cardiac output, septic cardiomyopathy (left, right, or biventricular heart failure), or right ventricular failure caused by acute respiratory distress syndrome). Veno-venous ECMO can be used in patients with sepsis and severe acute respiratory distress syndrome when conventional mechanical ventilation fails, and early application of veno-arterial ECMO in patients with sepsis-induced refractory cardiogenic shock may be critical in improving their chances of survival. When ECMO is indicated, the choice of an appropriate mode and determination of the optimal timing of initiation and weaning are critical, particularly in an experienced ECMO center. Furthermore, some special issues, such as ECMO flow, anticoagulation, and antibiotic therapy, should be noted during the management of ECMO support.