[Measurement of calcium fluorescent intensity in vital brain slice and mechanism of brain injury after circulatory arrest].

Objective: To examine the calcium fluorescent intensity of vital brain slice and study the mechanism of brain injury after circulatory arrest.

Methods: Eight pigs underwent 90 minutes' deep hypothermic circulation arrest (DHCA) and eight pigs underwent retrograde cerebral perfusion (RCP) through superior vena cava and then rewarmed for 120 minutes. Vital brain slices were obtained and the calcium fluorescent intensity was examined with laser confocal scanning microscope (LCSM). The morphological change was examined with light microscope and electron microscope.

Results: The calcium fluorescent intensity of vital brain slice was lower in RCP group than in DHCA group. The calcium fluorescent intensity of vital brain slice is correlated with the level of moderate and severe eosinophilic degeneration of neuron (r = 0.86, P < 0.05).

Conclusion: Calcium overload contributes to the injury of neuron after DHCA. RCP remarkably attenuates calcium overload, thus protecting the brain tissue.