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We wished to evaluate the safety and the advantages of using heparin-bonded extracorporeal membrane oxygenation (ECMO) to replace conventional cardiopulmonary bypass (CPB) in deep hypothermic circulation for complex cerebral aneurysm surgery.Heparin-bonded ECMO without the bridging tube and the cardiotomy reservoir was set up through the femoral vessels. Limited heparin was infused. In deep hypothermia, the ECMO blood flow was temporarily decreased as low as the neurosurgeons' request. It was applied to 4 patients with difficult intracranial aneurysms who were selected for the procedure. Clipping, wrapping, or vascular bypass was implemented to manage the aneurysms under deep hypothermia. The total heparin dosage used in the whole procedure was 9,875 +/- 1,625 U, and the mean ECMO time was 270 +/- 105 min. The blood consumption was packed red blood cell 3.0 +/- 0.5 U and fresh frozen plasma 3.8 +/- 2.3 U. Compared with our previous experiences using conventional CPB, ECMO did need less heparin and blood transfusions. Clipping was applied in 2 patients, wrapping in 1, and venous graft interposition was performed in 1. Mortality occurred in 1 patient (25%) due to brain herniation. This preliminary study suggested that the heparin-bonded ECMO without reservoir in deep hypothermia could be safe in cerebral aneurysm surgery under a low flow circuit.

Background B-type natriuretic peptide (BNP) is a marker of heart failure. In adult patients with heart failure, decreased BNP levels after implantation of ventricular assist devices may be indicative of recovery. However, BNP levels among pediatric patients receiving mechanical support are largely unknown. Methods Fifteen pediatric patients with cardiogenic shock who were supported by extracorporeal membrane oxygenation (ECMO) were evaluated. The BNP levels were determined before ECMO initiation, during ECMO support, and after ECMO removal. Results All patients had elevated BNP levels before initiation of ECMO (median, 1,430 pg/mL; range, 361 to 5,000 pg/mL). Among the 15 patients, 1 received heart transplantation. Extracorporeal membrane oxygenation was withdrawn in 2 patients, and the other 12 patients were weaned from ECMO. Four patients died after initially successful weaning from ECMO. The BNP levels of the nonsurvivors (median, 3,685 pg/mL; range, 2,494 to 5,000 pg/mL) were higher than those of the survivors (median, 1,127pg/mL; range, 108 to 3,030 pg/mL) on the next few days after ECMO removal ( p = 0.016). The BNP levels on the fourth day after removal of ECMO among the survivors (median, 498 pg/mL; range, 108 to 890 pg/mL) were lower than those among the nonsurvivors (median, 3,900 pg/mL; range, 3,230 to 5,000 pg/mL; p = 0.017). Conclusions Among pediatric patients supported with ECMO, the survivors had lower BNP levels than those who did not survive. We suggest that serial blood BNP levels can be potential markers for monitoring pediatric patients on mechanical circulatory support, and the concept merits further study.

Clinical Summary A 38-year-old male patient presented with severe respiratory distress. A large VSD with Eisenmenger syndrome had been diagnosed in the patient 2 years previously (Figure 1). A chest x-ray film revealed a pulmonary hemorrhage at the upper lobe of the right lung (Figure 2, A). The patient’s arterial oxygen concentration was extremely low (68%) even with ventilator support of 100% oxygen. A venovenous extracorporeal membrane oxygenator (ECMO) was inserted through the left femoral vein (outflow from the patient) and right jugular vein (inflow to the patient) in an attempt to increase his oxygen saturation. Because of severe mixing of blood across the VSD, the percutaneous saturation was still low (SpO2 74%) even with the venovenous ECMO support. Intermittent bradycardia occurred during the support, which was considered to be the result of inadequate tissue oxygenation. It seemed critical to find a way to decrease the mixing of deoxygenated blood across the VSD to save the patient’s life. Two days later, after a discussion with the patient’s family, we decided to perform an operation to close the VSD and create an atrial septal defect (ASD) with the use of cardiopulmonary bypass and aortic crossclamping. To prevent right-sided heart failure after the open operation, myocardial temperature was kept at 37°C with warm antegrade and retrograde cardioplegic solution. The large perimembranous VSD without aortic overriding was closed with a knitted Dacron patch and continuous suture with 4-0 polypropylene. A 1.5 1.5 cm fenestration at the atrial level was created to prevent congestion of the right side of the heart after closure of this large VSD. The operation was completed smoothly without right-sided heart failure developing. The patient was sent back to the intensive care unit with

Extracorporeal membrane oxygenation plays a very important role in resuscitation when patients are approaching impending death, because it can provide adequate cardiac and pulmonary support immediately. But percutaneous tunnel creation is a critical step for set-up of extracorporeal membrane oxygenation by percutaneous Seldinger technique. A guidewire dilator forceps used in percutaneous tracheostomy was tried to create the femoral subcutaneous tunnel. We found it could make easy the advancement of the percutaneous cannula into the vessels and over-dilatation of the vessels could also be prevented by controlled jaw opening.