Significance of SPECT as a Confirming Test of the Brain Death / 대한이식학회지

In Korea, brain death was established by the law in year 2000 but organ procurements from brain dead donors have been performed before the law era under the social tacit approval. Contrary to expectations, organ transplantation from brain dead donor have been much decreased in the law era. Electroencephalogram (EEG) is mandatory to confirm brain death in Korea. However EEG has several shortcomings and EEG wave may persist several hours after declaration of brain death by other tests. PURPOSE: To evaluate the significance of EEG and single photon emission computerized tomography (SPECT) as a confirming test of the brain death. METHODS: Clinical records of 42 cadaveric donor and their kidney recipients were reviewed retrospectively. Flat EEG was declared by two board certified neurologist or neurosurgeon. Tc99m-ECD SPECT was done in recent 10 donors who didn't show flat EEG at 24 hours after declarartion of brain death on clinical examination. And compared interval from renal transplantation to the moment when serum creatinine level went down below 2.0 mg/dl. RESULTS: Among 42 donors, 3 went to cardiac arrest while waiting flat EEG. And one another donor also went to cardiac arrest just after taking flat EEG. All the ten donors who took brain SPECT showed absence of cerebral blood flow. After showing circulatory arrest to the brain on SPECT another 3 to 23 hours were needed to get the flat EEG. There was no difference in interval between EEG only group (9.8 days) and EEG plus SPECT group (9.2 days). But the interval was prolonged in cardiac arrest group up to 20 days. CONCLUSION: We could get the falt EEG 3 to 23 hours after circulatory arrest to the brain on SPECT scan. While waiting to get flat EEG three donors went to cardiac arrest and kidneys from these cardiac arrest donor showed delayed graft function in all cases. Brain SPECT should be used as a confirming test of brain death.

Effect of External Beam Irradiation on Intimal Hyperplasia in Autografted Femoral Artery of Dog

BACKGROUNDS: It is well known that intimal hyperplasia is one of the most important cause of vascular graft failure in angioplasty, autogenous venous graft and prosthetic bypass graft. Clinical trials of drugs including antiplatelet agents, anticoagulant, corticosteroid, cyclosporine and prostaglandin were not satisfactory in suppressing intimal hyperplasia. Seeding of endothelial cell also have been done for this purpose with some success. There are several reports that endovascular low dose irradiation and external beam irradiation might reduce the amount of proliferative neointima after arterial injury. METHODS: In order to evaluate the effect of external beam irradiation on intimal hyperplasia in grafted vessel, femoral artery autografts using external jugular vein were performed in dogs, and studied the morphological finding under microscope and compared intimal hyperplasia between control and radiated groups. Group I (control) was not irradiated after graft. But experimental groups were irradiated with 6 Mev electron: Group II, 800 cGy on day 1; Group III, 400 cGy on day 1 and day 4 each; and Group IV, 800 cGy on day 4. Radiation efficacy on intimal hyperplasia was histologically assessed by measuring neointimal thickness at the proximal and distal site of grafted vessel at 6 weeks after graft. RESULTS: Mean neointimal thickness in all irradiated groups were significantly lesser than control group (p0.05). CONCLUSION: These data suggest that low dose external beam irradiation might suppress intimal hyperplasia in grafted vessel, but further study will be necessary to determine optimal dose and timing of radiation delivery, and its efficacy in long segment bypass graft.