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Description / Table of Contents: Summary The use of a biochemical marker for the early identification of cerebral injury associated with the corrective surgery of congential heart disease could possibly be of great diagnostic and prognostic value. S-100, a specific glia brain cell protein, may be released into serum following brain cell damage. The aim of this study was to investigate the levels of this biochemical marker in infants before and after corrective cardiac surgery by means of cardiopulmonary bypass (CPB). 42 newborns and infants were enrolled in this study. Blood samples were collected just before and immediately after CPB, and then again 2, 24, and 48 h postoperatively. The S-100 protein serum concentrations were analyzed using a commercially-available radioimmune kit. Peak values of S-100 were found immediately after surgery and during the first 2 h postoperatively, decreasing thereafter on the 2nd postoperative day to preoperative values (p 〈0.001). Newborn showed higher peak values (0,36 μg/l) than infants (0,95 μg/l). Newborns also had higher preoperative S-100-values than infants. A significant correlation was found between the peak values of S-100 and the age of the studied infants (r =–0,74; p 〈0.0001), and the minimal rectal temperature during CPB (r =–0,67; p = 0,0004). In conclusion: elevated S-100 serum values after cardiac surgery may provide information on ostensibly incurred cerebral injury. Neonates with cyanotic congenital heart disease showed significantly higher levels of Serum S-100 protein than older infants undergoing corrective cardiac surgery beyond the neonatal period. Follow-up studies are necessary to evaluate the significant prognostic value of this biochemical marker in the brain.

Description / Table of Contents: Summary Introduction: Neuropsychological morbidity following cardiac surgery of congenital heart disease (CHD) most likely considered to be due to alterations of cerebral oxygenation and hemodynamics could possibly be in part prevented by early detection by means of continous non-invasive monitoring during and after cardiac surgery. Measurement of regional cerebral blood saturation (rSO2) by near infrared spectroscopy (NIRS) mays provide qualitative information on cerebral oxygen supply and consumption. The aim of the sutdy was to investigate the relationship between the change in rSO2 and other hemodynamic parameters during the different stages of CPB in a heterogeneous group of infants and children undergoing corrective and palliative cardiac surgery by means of full flow CPB. Methods: 50 children and infants (15 infants with cyanotic CHD, median age 18 days (5 days–7 months); 15 children with cyanotic CHD, median age 4 years (1–9 years); 20 children with non-cyanotic CHD, median age 4 years (1–16 years)) undergoing surgical correction by means of full flow cardiopulmonary bypass (CPB) (120–150 ml/kg/BW) with moderate hypothermia (24±6°C) and alpha stat method were included in this study. Total circulatory arrest was used only in 3 infants. Continuous measurement of rSO2 was performed using a two channel cerebral oximeter (INVOS 31000A®, somanetics, USA). The sensor with a light source and superficial and deep received was placed in standardized localization at the left temporal head side. Hemodynamic parameters were simultaneously documented. Results: Before CPB the mean values of rSO2 in children with cyanotic congenital heart disease (CHD) were significantly lower (p=0.002) than those with non-cyanotic CHD. After onset of cardiopulmonary bypass (CPB) there was a gradual fall in rSO2 with achieved minimal values within 14–40 minutes (p〈0.01). During CPB these values of rSO2 were nearly 8–10% lower, particularly in the younger infants. After the end of CPB there was nearly subsequent restoration of these values in the older children. After rewarming and cessation of CPB rSO2 decreased up to 15% in individual patients particularly in young infants reflecting a higher O2 consumption. There relationship between the change in rSO2 and mean arterial pressure (MAP), central venous pressure (CVP), hemoglobin concentration (Hb) and temperature was in part significant in all infants during the period of monitoring. Conclusion: Change of cerebral oxygenation independent of the change in conventional hemodynamic parameters and arterial blood oxygenation suggests the necissity of separate monitoring of cerebral oxygenation and hemodynamics during and after cardiac surgery in infants and children. Further follow up studies are necessary to evaluate the neurological significance of the magnitude and duration of the decreased change in rSO2 during and after.

Description / Table of Contents: Zusammenfassung Kinder mit progredienter dilatativer Kardiomyopathie können auf der Warteliste zur Herztransplantation versterben, da bei ihnen das Krankheitsbild besonders rasch mit Kreislauf- und Multiorganversagen fortschreitet und ein passendes kindliches Spenderangebot nicht schnell genug verfügbar ist. Bei 15 Kindern im Alter von vier Monaten bis 15 Jahren führten wir im Stadium des nicht mehr medikamentös therapierbaren Herzversagens und beginnendem Multiorganversagen eine Kreislaufunterstützung mittels Kunstherz (Ventrikuläres Assist Device, „Berlin Heart”) durch. Alle Kinder befanden sich in progredientem Schock und waren mindestens einmal reanimiert worden, bevor wir uns zur Implantation entschlossen. Das Kunstherz besteht aus zwei pneumatisch angetriebenen extrakorporalen Blutpumpen, vier Silikonkanülen zur venösen und arteriellen Verbindung zwischen Patient und Pumpe und einem elektropneumatischen pulsatilen Antrieb. Zwölf der 15 Kinder konnten wir mit dem System während 1 bis 98 Tagen (Mittel: 24 Tage) am Leben erhalten und die Wartezeit bis zur Herztransplantation überbrücken. Neun Kinder waren während der Unterstützungszeit extubiert und mobilisiert. Drei Kinder verstarben vor Erreichen einer Transplantation an Blutung, Sepsis und Lungenversagen, bei einem überlebenden Kind trat ein Infarkt der arteria cerebri media auf. Sieben transplantierte Langzeitüberlebende sind beschwerdefrei und sozial vollintegriert. Durch modifizierte Technik ist das Kunstherz auch im Säuglings- und Kleinkindalter einsetzbar. Dadurch können wir Kinder mit terminaler Herzinsuffizienz bei dilatativer Kardiomyopathie für Wochen und Monate am Leben erhalten und die Zeit bis zur Transplantation überbrücken.