vasoactive-intestinal-peptide and Brain-Damage--Chronic

To investigate brain changes in induced deep core hypothermia (15 degrees C) with circulatory arrest, five groups of neonatal pigs were subjected to cardiopulmonary bypass (CPB), with circulatory arrest (CA) periods varying from 70-120 min. The parameters analysed were: 1. Histology and electron microscopy of the brain six hours post-CPB, 2. Creatinophosphokinase (CPK) from cerebrospinal fluid (CSF), 3. Vasointestinal neuropeptide (VIP) and 7B2 specific neuropeptide both in plasma and brain tissue. The earliest morphological changes were seen after 90 min CA and were highly significant after 120 min arrest. These changes involved mainly the Purkinje cells of the interior half of the cerebellum with vacuolation in their cytoplasm. A rise in CPK in CSF occurred in all piglet-groups. The differences among the various groups were highly significant at 2 and 5 h post-CPB. (P < 0.05). Statistically significant differences were not exhibited among the various groups both in serum and brain tissue total mean values of VIP and 7B2 neuropeptides. We suggest that 1. The cerebellar region is the most sensitive where ischemic lesions attain their maximal severity and extent; the frequency and pattern of selective vulnerability of the cerebellum may be related primarily to its pattern of blood supply 2. The maximum time of CA without histopathological sequelae should not exceed 70 min.

Topics: Anesthesia, General; Animals; Brain; Brain Damage, Chronic; Creatine Kinase; Heart Arrest, Induced; Hypothermia, Induced; Hypoxia, Brain; Microscopy, Electron; Neuropeptides; Swine; Thoracotomy; Vasoactive Intestinal Peptide