Extracorporeal cardiopulmonary resuscitation (ECPR) serves as an alternative method for patients experiencing cardiac arrest (CA) when conventional CPR (C-CPR) fails to achieve sustained return of spontaneous circulation (ROSC) (Damps et al., 2023, Richardson et al., 2021, Kumar, 2021). This technique involves the use of extracorporeal membrane oxygenation (ECMO) to provide circulatory and respiratory support, and it has demonstrated improved outcomes in patients with refractory CA (Scquizzato et al., 2022, Alfalasi et al., 2022, Lucchini et al., 2023a). However, despite these advancements, favorable outcomes, including survival, disability, and neurological function, remain poor for both in-hospital CA (IHCA) and out-of-hospital CA (OHCA) cases (Lucchini et al., 2023b, Lee et al., 2023a). Research indicates that a significant number of individuals who survive cardiac arrest subsequently experience functional disabilities, leading to reduced capacity for self-care activities and diminished quality of life (Kongpolprom and Cholkraisuwat, 2019, Ryu et al., 2019). Moreover, some survivors may face mental impairments that hinder their ability to return to work, even if they only have mild physical disabilities (Schluep et al., 2021, Wimmer et al., 2021, Ho et al., 2023).

Veno-venous ECMO (VV-ECMO) and veno-arterial ECMO (VA-ECMO) are two types of extracorporeal membrane oxygenation. VA-ECMO provides cardiac and respiratory support, using cannulas in major veins and arteries. It supports both failing heart and lungs. VV-ECMO focuses solely on respiratory support, using cannulas in major veins. It is used for severe respiratory failure. Both VA-ECMO and VV-ECMO can be performed with either peripheral or central cannulation. In some cases, femoral artery reperfusion cannulas may be used for additional support.

Following cardiac arrest, the neurological disability outcomes of individuals are influenced by cerebral blood flow (CBF) (Iordanova et al., 2017, Sandroni et al., 2021). Prompt restoration of systemic circulation and oxygenation is crucial to achieving positive outcomes and meeting the brain's oxygen demand (Valkov et al., 2022, Van Den Brule et al., 2018). Typically, patients who are resituated from CA experience changes in CBF autoregulation (Kazmi et al., 2018, Fantini et al., 2016). However, in the case of ECPR, it is challenging to predict how highly oxygenated continuous flow through ECMO affects CBF autoregulation (Aboul-Nour et al., 2023, Said et al., 2020). Additionally, favorable outcomes may be influenced by early CPR, timing of recovery in cardiac and lung function, the level of ECMO support, and CBF autoregulation (Cai et al., 2023, Kim et al., 2020). Patients undergoing ECPR have higher mortality rates and poorer neurological outcomes when there are longer periods of collapse to CPR (no-flow time) and CPR to ECPR (low-flow time) (Matsuyama et al., 2020, Murakami et al., 2020). Furthermore, the duration of both no-flow time (NFT) and low-flow time (LFT) and their impact on neurological outcomes after cardiac arrest vary depending on various factors (Park et al., 2020, Elmelliti et al., 2022). Hence, ECPR is a complex intervention that requires a highly trained team, specialized equipment, and multidisciplinary support within a healthcare system, and it carries the risk of several life-threatening complications (De Charrière et al., 2021).

Multiple factors appear to influence the favorable outcomes in patients undergoing ECMO following cardiac arrest (Klee and Kern, 2021, De Charrière et al., 2021, Minion et al., 2022). Understanding the factors associated with neurological disability outcomes in ECMO patients is crucial for optimizing patient care and improving overall results (Illum et al., 2021). By identifying and addressing these factors, healthcare providers can enhance patient care and strive for better neurological outcomes in individuals receiving ECMO support. While several predictors of neurological disability outcomes have been reported in the context of conventional CPR, limited data is available on disability and neurologic prognosis after ECPR. Furthermore, no study has been conducted in Qatar to determine the influencing factors on functional outcomes of IHCA and OHCA. This study aimed to identify the factors associated with neurological disability outcomes in patients who undergo ECMO after cardiac arrest, in order to address the knowledge gap.