Discussion
It is necessary to understand that though the majority of children are not seriously affected, there may be a subset of group children where the COVİD-19 can progress rapidly deteriorate the respiratory functions (5). Our patient is the youngest patient ever reported with the progression of SARS-CoV-2 to severe disease requiring ECMO support after cardiac surgery. The respiratory deterioration of this case is important for understanding SARS-CoV-2 disease in newborns undergoing cardiac surgery. Our patient, who developed rapid respiratory disorder in the early postoperative period, was required ECMO support within the next 24 hours despite lung protective ventilation and high PEEP theraphy.
Current evidence shows that excessive inflammation, oxidation and an extreme immune reaction play a significant role in the pathogenesis of COVID-19 (6). Direct myocardial damage via angiotensin-converting enzyme 2, viral pneumonia, acute respiratory distress syndrome (ARDS), acute lung injury, hypoxia induced myocardial damage, CPB related systemic inflammatory response syndrome, pulmonary hypertansion related to CHD may subscribe to inflammation course (6). Moreover, these events cause a cytokine storm and results in ARDS (6). The immunity of the patients has a major influence on the COVID-19 seriousness, and those with low immune function, such as neonates, may be more susceptible, especially after CPB (6).
According to the Extracorporeal Life Support Organization (ELSO) registry as of 5 December 2020, ECMO support was used in 3543 confirmed SARS-CoV-2 patients and in hospital mortality was 45% (7). Thrombosis and bleeding complications are well-known risks of ECMO support. Some studies announced a 70% incidence of bleeding and a 37% incidence of thrombosis complications in children supported by ECMO (8). But ECMO experience and literature is restricted in the SARS-CoV-2 disease (9). Kaushik et al. reported a 5-year-old male patient who underwent ECMO support with carotid artery cannulation due to SARS-CoV-2 multisystem inflamatory syndrome (9). Unfortunately, right anterior and middle cerebral artery infarction occurred on ECMO day 6 and finally the patient succumbed to. The cause of stroke, for in this case, may be multifactorial such as SARS-CoV-2 associated thromboembolic complications or carotid artery cannulation strategy. A single-center reported a 5% incidence of acute ischemic stroke on 221 patients with SARS-CoV-2, and in addition, the incidence of ECMO-associated stroke in children is known to be between 5.6% and 7.8% (10,11).
In our case, ARDS findings started on the postoperative 3rd day and the respiratory functions of the patient deteriorated rapidly. Considering that thromboembolic complications associated with SARS-CoV-2 may increase, veno arterial ECMO support was applied with central cannulation. Maybe for this reason, we did not observe thromboembolic neurological complications, which may give symptoms such as anisocoria or decrease in NIRS values during a total of 17 days of ECMO support.
The results of ECMO support in ARDS due to Covid 19 are associated with high mortality. Henry et al. reviewed 234 COVID-19-related ARDS patients in China, 17 of whom (7.25%) received ECMO, with a mortaliy rate of 94.1% in ECMO patients compared to 70.9% in conventional patients (12). In our opinion, in addition to having undergone cardiac surgery in the neonatal period, high ECMO mortality rates in ARDS due to COVID-19 negatively affected survival in our patient.