Transition from Simple V-V to V-A and Hybrid ECMO Configurations in COVID-19 ARDS.

In SARS-CoV-2 patients with severe acute respiratory distress syndrome (ARDS), Veno-Venous Extracorporeal Membrane Oxygenation (V-V ECMO) was shown to provide valuable treatment with reasonable survival in large multi-centre investigations. However, in some patients, conversion to modified ECMO support forms may be needed. In this single-centre retrospective registry, all consecutive patients receiving V-V ECMO between 1 March 2020 to 1 May 2021 were included and analysed. The patient cohort was divided into two groups: those who remained on V-V ECMO and those who required conversion to other modalities. Seventy-eight patients were included, with fourteen cases (18%) requiring conversions to veno-arterial (V-A) or hybrid ECMO. The reasons for the ECMO mode configuration change were inadequate drainage (35.7%), inadequate perfusion (14.3%), myocardial infarction (7.1%), hypovolemic shock (14.3%), cardiogenic shock (14.3%) and septic shock (7.1%). In multivariable analysis, the use of dobutamine (p = 0.007) and a shorter ICU duration (p = 0.047) predicted the conversion. The 30-day mortality was higher in converted patients (log-rank p = 0.029). Overall, only 19 patients (24.4%) survived to discharge or lung transplantation. Adverse events were more common after conversion and included renal, cardiovascular and ECMO-circuit complications. Conversion itself was not associated with mortality in the multivariable analysis. In conclusion, as many as 18% of patients undergoing V-V ECMO for COVID-19 ARDS may require conversion to advanced ECMO support.

[Perforation of the internal jugular vein during cannulation for haemodialysis]. / Uszkodzenie zyly szyjnej wewnetrznej kaniula dializacyjna.

BACKGROUND: Reliable temporary vascular access is necessary for haemodialysis when the establishment of permanent access is not possible. Double-lumen catheters are favoured in most cases. These catheters are commonly inserted percutaneously using anatomic landmarks, but the technique is far from being perfect and serious complications may occur during the procedure. We describe a serious and potentially lethal complication of internal jugular venous cannulation. CASE REPORT: A 50-year-old woman was transferred from another hospital because of misplacement of a tunnelled permanent haemodialysis catheter and internal bleeding. A computed tomographic angiogram of the chest revealed that the catheter had migrated to the mediastinum. Emergency surgery with cardiopulmonary bypass was performed, the catheter removed, and the damaged left internal jugular and right subclavian veins were reconstructed. CONCLUSION: Migration of a dialysis catheter outside the vascular bed is a potentially lethal complication. Removal of a misplaced catheter may lead to massive uncontrolled bleeding and should be managed surgically.