Minimized Hemodiafiltration for Extracorporeal Membrane Oxygenation in Infants.

BACKGROUND: Fluid overload is a serious complication in the treatment of infants with extracorporeal membrane oxygenation (ECMO). Volume overload leads to prolonged ECMO therapy if left untreated. The renal replacement therapy of choice in pediatric patients is peritoneal dialysis or conventional dialysis using a "large" hemofiltration machine via a Shaldon catheter or directly connected to the ECMO system. This study describes the implementation of a novel minimized hemodiafiltration (HDF) system in pediatric patients on ECMO. METHODS: This retrospective analysis included 13 infants up to 5 kg who underwent 15 veno-arterial (V-A) ECMO runs with HDF. A minimized HDF system is integrated into an existing ECMO system (18-mL priming volume), connected post-oxygenation to the venous line, before the ECMO pump. Two infusion pumps are attached to the inlet and outlet of the hemofilter to control the HDF system.In addition to retention values (creatine and urea) at six defined time points, flow rates, dialysis parameters, and volume withdrawal were examined, as well as the number of HDF system changes. RESULTS: With a mean ECMO runtime of 156 hours, the HDF system was utilized for 131 hours. The mean blood flow through the hemofilter was 192 mL/min. The mean dialysate flow was 170 mL/h, with a mean volume deprivation of 39 mL/h. The HDF system was changed once in seven cases and twice in three cases. CONCLUSION: There were no complications with the minimized HDF system in all 15 applications. It allows safe patient volume management when treating infants with ECMO, with effective elimination of urinary substances.

Microplegia in paediatric hearts.

INTRODUCTION: A basic prerequisite for a good surgical outcome in heart surgery is optimal myocardial protection. However, cardioplegia strategies used in adult cardiac surgery are not directly transferable to infant hearts. Paediatric microplegia, analogous to Calafiore cardioplegia used in adult cardiac surgery, offers the advantage of safe myocardial protection without haemodilution. The use of concentration-dependent paediatric microplegia is new in clinical implementation. MATERIAL AND METHODS: Paediatric microplegia has been in clinical use in our institution since late 2014. It is applied via an 1/8 inch tube of a S5-HLM roller pump (LivaNova, Italy). As cardioplegic additive, a mixture of potassium (K) 20 mL (2 mmol/mL potassium chloride 14.9% Braun) and magnesium (Mg) 10 mL (4 mmol/mL Mg-sulphate Verla® i. v. 50%) is fixed into a syringe-pump (B. Braun, Germany). This additive is mixed with arterial patient blood from the oxygenator in different flowdependent ratios to form an effective cardioplegia. TECHNIQUE: After microplegia application of initially 25 mmol/L K with 11 mmol/L Mg for 2 min, a safe cardioplegic cardiac arrest is achieved, which after release of the coronary circulation, immediately returns to a spontaneous cardiac-rhythm. In the case of prolonged aortic clamping, microplegia is repeated every 20 min with a reduction of the application dose of K by 20% and Mg by 30% (20 mmol/L K; 8.5 mmol/L Mg) and a further reduction down to a maintenance dose (15 mmol/L K; 6 mmol/L Mg) after additional 20 min. SUMMARY: The microplegia adapted to the needs of paediatric myocardium is convincing due to its simple technical implementation for the perfusionist while avoiding haemodilution. However, the required intraoperative interval of microplegia of approx. 20 min demands adapted intraoperative management from the surgeon.

Mobility and freedom of movement: A novel out-of-hospital treatment for pediatric patients with terminal cardiac insufficiency and a ventricular assist device.

Background: Due to rapid medical and technological progress, more and more pediatric patients with terminal cardiac insufficiency are being implanted with a ventricular assist device as a bridge to transplant without legal approval for hospital discharge. EXCOR® Active is a recently developed mobile driving unit for the EXCOR® ventricular assist device (EXCOR® VAD) with a long-lasting battery life that can manage small blood pumps, offering improved mobility for pediatric patients. This study strives to elaborate the requirements necessary for a safe home healthcare environment (HHE) for pediatric patients on EXCOR® VAD powered by the EXCOR® Active driving unit. Materials and methods: Patient- and device-related preconditions (medical, ethical, psychological, technical, structural, organizational) were analyzed with regard to feasibility and safety in three individual patient cases. Included were pediatric patients with terminal cardiac insufficiency in a stable medical condition receiving in-hospital treatment with a univentricular or biventricular EXCOR® VAD powered by EXCOR® Active. Analysis was single-center, data was obtained 05/2020-02/2022. Results: A total of three patients on EXCOR® VAD were identified for HHE treatment with the EXCOR® Active driving unit. Switch was performed safely and increased mobility led to improved psychomotor development and improved quality of life. No complications directly related to HHE-treatment occurred. One patient recently underwent an orthotopic heart transplant, one patient remains in HHE, and one patient died due to a complication not related to the HHE. Ethical approval for off-label use was obtained and patients and parents were given the required technical training and psychological support. Caregivers and medical professionals involved in the patients' care at home were briefed intensely. Remote consultations were implemented and interdisciplinary in-hospital checks reduced to a long-term 4-week-scheme. Conclusion: While it is challenging to discharge pediatric patients being treated with a paracorporeal ventricular assist device (EXCOR® VAD) from hospital, it is feasible and can be managed safely with the novel driving unit EXCOR® Active. A HHE may help to improve patients' psychomotor development, offer normalized social contacts and strengthen both patients' and parents' physical and mental resources. Legal approval and another study with a larger sample size are warranted.