OBJECTIVE: To study the cerebral blood flow changes in irreversible comatose patients and investigate the correlation between the results of transcranial Doppler (TCD) and clinical evaluation of brain function. METHODS: TCD studies were performed in 92 patients who were excluded from the possibility of reversible coma and all of them had Glasgow Coma Scale of 3. Their brain stem reflections all disappeared. Detection of the blood flow in bilateral middle cerebral arteries was carried out through temporal window in all the patients and in 42 of the 92 cases the blood flow of the basilar artery was detected through occipital or peri-occipital window. Bilateral middle cerebral artery were taken as the main arteries for evaluation. The positive standard is the appearance of one of the following characteristic blood flow, i.e. brief systolic forward flow or systolic spikes and diastolic reverse flow, brief systolic forward flow or systolic spikes and no diastolic flow and no detectable flow signals. The examination was repeated after 12 h. RESULTS: 68 cases were positive in the initial examination (73.9%) and 74 cases were positive after 12 h (80.4%). CONCLUSION: TCD can be an effective and objective index in the evaluation of irreversible termination of brain function.
OBJECTIVE: To study the cerebral blood flow changes in irreversible comatosepatients and investigate the correlation between the results of transcranial Doppler (TCD) and clinical evaluation of brain function. METHODS:TCD studies were performed in 92 patients who were excluded from the possibility of reversible coma and all of them had Glasgow Coma Scale of 3. Their brain stem reflections all disappeared. Detection of the blood flow in bilateral middle cerebral arteries was carried out through temporal window in all the patients and in 42 of the 92 cases the blood flow of the basilar artery was detected through occipital or peri-occipital window. Bilateral middle cerebral artery were taken as the main arteries for evaluation. The positive standard is the appearance of one of the following characteristic blood flow, i.e. brief systolic forward flow or systolic spikes and diastolic reverse flow, brief systolic forward flow or systolic spikes and no diastolic flow and no detectable flow signals. The examination was repeated after 12 h. RESULTS: 68 cases were positive in the initial examination (73.9%) and 74 cases were positive after 12 h (80.4%). CONCLUSION:TCD can be an effective and objective index in the evaluation of irreversible termination of brain function.