A pilot study of evaluation of cerebral function by S100β protein and near‐infrared spectroscopy during cold and warm cardiopulmonary bypass in infants and children undergoing open‐heart surgery*

Abstract

SummaryCerebral injury in children undergoing cardiopulmonary bypass (CPB) remains a major source of morbidity. The effect of cardiopulmonary bypass temperature on cerebral function in terms of serum S100b protein level and cerebral oxygenation monitored by near infrared spectroscopy (NIRO-300) in children is not known. In this study, 18 children undergoing open-heart surgery at the Hospital for Sick Children in London were equally assigned by minimisation to warm (35 ± 1°C) or cold (25 ± 1°C) CPB. Changes in S100b protein and cerebral oxygenation were studied in both groups. S100b protein serum level increased significantly after CPB in both groups. There was no significant difference in serum S100b protein concentrations between the two groups. However, cerebral oxygenation in terms of tissue oxygen index (TOI) was significantly impaired during rewarming from cold CPB. Five patients were desaturated (TOI < 50%) during rewarming in the cold bypass group compared to two in the warm patients. This study supports the use of warm CPB in children undergoing open-heart surgery, although further studies recruiting more patients are warranted.

S100 and S100β: biomarkers of cerebral damage in cardiac surgery with or without the use of cardiopulmonary bypass

“…Pulsatile flow lowers cerebral destruction than laminar flow [ 50 ] . S100 was nonsignificantly higher in cold than in warm CPB patients [ 63 ] .The S100β rise was significantly less in patients administered sevoflurane in comparison to total intravenous anesthesia [ 64 ] . CPB with covalent bonded heparin attached to the CPB circuit in combination with a reduced systemic heparin dose seemed to reduce the operative stroke [ 88 ] .…”

Changes in cerebral oxygenation during cold (28°C) and warm (34°C) cardiopulmonary bypass using different blood gas strategies (alpha‐stat and pH‐stat) in patients undergoing coronary artery bypass graft surgery

“…More importantly, there is an increased risk of undetected brain hyperthermia during rewarming because nasopharyngeal and oesophagyeal temperatures underestimate brain temperature (24–27). Recently, avoidance of early rewarming during warm CPB (35 ± 1°C) in children has been reported to prevent desaturation (28), which has been described at the first 40 min of warm CPB (10).…”

Neuromonitoring mittels S100B-Protein: Stellenwert für die Neonatologie, pädiatrische Intensivmedizin und Pädiatrie

“…Neurologische Störungen nach Herzoperationen stellen eine schwerwiegende Komplikation dar [47]; sie sind z. T. initial schwer festzustellen und kognitive Funktionsstörungen werden möglicherweise erst in späteren Jahren evident. Daher scheint auch für diese Patientenpopulation die Bestimmung von S100B sinnvoll, um erstens möglichst frühzeitig neurologische Schädigungen bzw.…”

“…Im Rahmen von Operationen bei Kindern unter Verwendung einer Herz-Lungen-Maschine kommt es zu einem signifikanten Anstieg von S100B-Protein [30,32,47]. Allerdings ist nur ein Anstieg zu einem Zeitpunkt 48 h nach Ende der Herz-LungenMaschine mit einer neurologischen Schädigung assoziiert; die transiente Erhöhung von S100B-Protein könnte neben der Freisetzung aus nicht-neuralem Gewebe ursächlich mit einer systemischen Inflammationsreaktion in Zusammenhang stehen [41].…”