Extracorporeal life support in pediatric patients with congenital heart diseases: outcome of a single centre.

AIM: In pediatric patients with congenital heart disease low cardiac output (LCO) is the principal complication after corrective heart surgery. In LCO refractory to all therapeutic options, mechanical circulatory support is the final method to keep these patients alive. In this present study the authors reviewed the outcome of pediatric patients who required mechanical circulatory support after corrective surgery with extracorporeal membrane oxygenation or ventricle assisted devices (VAD). METHODS: A retrospective single centre consecutive cohort study was carried out in children who required different mechanical circulatory support indicated by postcardiotomy low output syndrome between 1991 and 2004. A total of 20 patients received extracorporeal life support. The indications for surgery were: 12 transposition of great arteries, 1 Bland-White-Garland syndrome, 3 tetralogy of Fallot, 1 hypoplasia of aortic arch, 1 total anomalous pulmonary vein connection, and 2 ventricle septum defect. RESULTS: Mean age was 1.29 years. Mean duration of assist was 8.87 days. Seven patients out of 20 survived, six could be discharged after myocardial recovery from LCO and one could be discharged after successful heart transplantation. The overall mortality in patients with extracorporeal life support was 65%. The causes of death were multiorgan failure and bleeding in one case was a VAD related complication. CONCLUSION: The use of extracorporeal life support (ECLS) shows a high mortality rate. However, ECLS can still help to keep some of those patients alive. Mechanical support devices are the ultimate chance to save time, to increase survival and to bridge the time until heart transplantation.

Mechanical circulatory support: reality and dreams experience of a single center.

Because of the increasing number of patients waiting for heart transplantation and the decreasing number of donor organs, mechanical circulatory support has become a generally accepted therapeutic option. Several high-tech devices developed in the last 15 years differ in terms of location, kind of support, and driving units. They are suitable for different patients and their therapeutics objectives. Based on 13 years of experience, we developed a specific protocol for selection and management of patients and devices. Six hundred two patients have received mechanical circulatory support (MCS) in our institution since 1987. The indication spectrum includes cardiogenic shock for various reasons: acute myocarditis, right heart failure, acute rejection and postcardiotomy heart failure, alternative to transplantation, and bridge to recovery. Eight different systems are in use at our center. The extracorporeal devices, the Biomedicus centrifugal pump (n = 169) and the Abiomed BVS 5000 (n = 92) are used for short-term support. The Thoratec VAD (n = 179), and Medos HIA-VAD (n = 10) located in paracorporeal position preferably used for midterm support. Novacor LVAS (n= 96), and HeartMate (n = 58) are partially implantable systems used for long-term ventricular assistance in patients who did not require biventricular support. The advantage of the implantable devices is the option of discharging patients under support if they fulfill special criteria before being discharged to home. Eighty-five LVAD patients were discharged home with support, Novacor (n = 52), HeartMate (n = 27), ThoratecTLC-II (n = 8), Lionheart (n = 3) fulfill our criteria for being discharged home while on support. Careful postoperative patient management does not exclude a variety of complications. Bleeding: occurred in 22-35% of patients, right heart failure in 15-26%, neurologic disorder in 7-28%, infection in 7-30%, and liver failure in 11-20%. Complications varied with different devices, and the patients' preoperative conditions. Eighty-five patients fulfilled the criteria of our out of hospital program (OOH) and were discharged from hospital for a mean period of 184 days. Readmission was necessary for complications caused by thromboembolism and infection. This report describes our patient device selection criteria as a bridge to transplant setting.

The heater-cooler unit--a conceivable source of infection.

Even drinking water is contaminated with pathogenic microorganisms. This does not necessarily pose a risk for healthy individuals, but it may result in serious consequences in people with impaired immune systems. This is particularly valid if drinking water is used for medical purposes. The heater-cooler unit (HCU) connected to heat exchangers or blankets by tubing, the connection is closed water circuit that contains microorganisms and algae. While connecting the tubing to the heat exchanger, spilling of water cannot be avoided. Microbiological examinations showed that germs and particles pollute the units. Exposure to the patient and the OR equipment has the potential to increase the risk of infection should the HCU water come in contact with the patient. As a result of the high incidence of particle and algae in the HCU, malfunction occurs. Sampling shows >1000/mL CFU (colony forming units) at 36 degrees C and 55/mL CFU at 20 degrees C on average. The specific findings include Pseudomonas and Legionella. Disinfecting HCU is very difficult. Often HCUs do not provide any technology to reduce bacterial or other contamination. The instructions for use of oxygenators often exclude the use of disinfectants. Maintenance instructions for the HCU advocate the use of disinfectants that carry the risk of oxygenator damage and of heat exchanger leakage. The effect of chemical disinfectants and heat exchanger membranes have not been examined, they may impair heat exchanger permeability and function. As an alternative to chemical and thermal disinfection, we used the alternative method of filtration. Using a membrane filter element, we noticed a decreasing number of CFUs from 55 to sterile conditions at 20 degrees C and from >1000 CFUs to 100 CFUs at 36 degrees C (Figure 1). In addition, we noticed a removal of other particles and algae. In conclusion, we have demonstrated a technique that is simple to implement and effectively reduces the microbiological load of the water in the heater-cooler unit.