Neuroprotective effect of selective antegrade cerebral perfusion during prolonged deep hypothermic circulatory arrest: Cerebral metabolism evidence in a pig model

Abstract

Objective:The aim of this study was to elucidate the mechanism of cerebral injury and to evaluate selective antegrade cerebral perfusion (SACP) as a superior neuroprotective strategy for prolonged deep hypothermic circulatory arrest (DHCA).Methods:Twelve pigs (6–8-week old) were randomly assigned to DHCA alone (n=6) and DHCA with SACP (n=6) at 18°C for 80 min groups. Serum S100 was determined using an immunoassay analyzer. The concentrations of cerebral dialysate glucose, lactate, pyruvate, glycerol, and glutamate were measured using a microdialysis analyzer.Results:Compared with a peak at T4 (after 60 min of rewarming) in the DHCA group, the serum S100 in the SACP group was significantly lower throughout the study. The DHCA group was susceptible to significant increases in the levels of lactate, glycerol, and glutamate and the ratio of lactate/pyruvate as well as decreases in the level of glucose. These microdialysis variables showed only minor changes in the SACP group. There was a positive correlation between cerebral lactate and intracranial pressure during reperfusion in the DHCA group. However, the apoptosis index and C-FOS protein levels were lower in the SACP group.Conclusion:Metabolic dysfunction is involved in the mechanism of cerebral injury. SACP is a superior neuroprotective strategy for both mild and prolonged DHCA.

Proton magnetic resonance spectroscopy assessment of neonatal brain metabolism during cardiopulmonary bypass surgery

“…Survival rates for neonatal congenital cardiac surgery are currently 90% or higher, but 25%–50% of these patients later developed neurodevelopmental deficits, depending on the complexity of their disease, surgery, and multiple other factors 3,12 . Unfortunately, despite the theoretical advantages of CPB surgery using hypothermia with added cerebral perfusion, recent studies of neurodevelopment outcomes have not shown a significant difference, 13 suggesting that details regarding brain metabolism and causes of neurological injuries during these procedures are not fully understood 14,15 . Improved measurements of brain injury during CPB surgery are likely to enable methods to reduce long‐term negative neurodevelopmental outcomes for these patients.…”

“…3,12 Unfortunately, despite the theoretical advantages of CPB surgery using hypothermia with added cerebral perfusion, recent studies of neurodevelopment outcomes have not shown a significant difference, 13 suggesting that details regarding brain metabolism and causes of neurological injuries during these procedures are not fully understood. 14,15 Improved measurements of brain injury during CPB surgery are likely to enable methods to reduce long-term negative neurodevelopmental outcomes for these patients.…”

“…Swine have been the most widely employed preclinical models, with measurements of brain blood flow and metabolism during CPB surgery obtained using a variety of techniques, including laser Doppler, 16 optical imaging, 17 microdialysis, 14,15 histopathology, 13,18 MRI (notably diffusionweighted imaging), 19 and magnetic resonance spectroscopy (MRS). 20 Among these methods, 1 H MRS is one of the most powerful, in principle allowing the noninvasive real-time monitoring of up to 20 brain metabolites.…”