Predictors of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) failure: analysis of comorbidities and complications – a 10-year experience
Abstract
Introduction
Regardless of its effectiveness, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support is not a risk-free method. Its use is associated with high complication and mortality rates, especially in patients with comorbidities. The success of this method and prognosis depend on a number of factors, and correct patient selection and early recognition of predictors of method failure are essential to ensure optimal support outcomes. In addition to cardiorespiratory failure, the most frequently discussed predictors of VA-ECMO failure include the presence of other diseases, age, and the patient’s general health status before starting support.
Aim
The aim of this analysis was to evaluate the results and explore factors that might act as predictors of VA-ECMO failure as a method in critical patients. It focuses on clinical indicators and available anamnestic data that may facilitate early identification of patients at high risk of support failure, and possible intervention to ensure a better prognosis for patients with severe cardiovascular failure.
Material and methods
This is a retrospective single-center study conducted at the Cardiac Surgery Clinic of the University Hospital Olomouc within the ECMO center. A cohort of 124 patients supported by VA-ECMO with critical cardiorespiratory failure in the period 2012–2021 was analyzed. Ten patients were excluded from this cohort – patients supported with ECMO as a “back up” during extremely high-risk percutaneous interventions, especially procedures on the last patent coronary artery or due to technically unsuccessful cannulation. A series of 114 full support ECMO cases were analyzed.
Data collection and outcomes
The cohort included 114 patients supported between 2012 and 2021: 86 (75.4%) men and 28 (24.6%) women, median age 58 years (range: 8–81 years), median age 58 years (range: 8–77 years), median age 59.5 years (range: 18–81 years).
The distribution of patients according to the indications for VA-ECMO cardiopulmonary support is shown in the results.
Statistical analysis
The data are presented as percentages for categorical variables and as medians. Statistical analysis was conducted using IBM SPSS Statistics version 23 (Armonk, NY: IBM Corp. USA). The Mann-Whitney U test was used to analyze continuous variables in independent samples. Spearman correlation analysis and the χ2 test (Fisher’s exact test) were used. The level of statistical significance was set at p = 0.05 for all analyses. We test the normal distribution using the Shapiro-Wilk test. Figures were created using Microsoft Excel for Office 365 (Microsoft, Redmond, WA, USA).
Results
Indications
The indications for VA-ECMO support can be classically summarized as cardiorespiratory failure; however, the individual conditions encountered while determining the indications for support are listed below in Table I. The largest indication cluster is acute coronary syndrome, followed by heart failure after cardiotomy. Patients with unclear etiology of heart failure in critical condition formed a significant indication group. The statistical assessment of the association between hospital exit, 30-day, 90-day and 12-month survival with the indication diagnoses was performed. Statistical assessment of the association between hospital exit, 30-day, 90-day and 12 month survival with the indication diagnoses in our patient group did not show a correlation.