RESUMO
We evaluated the relationship of global cerebral blood flow, cross-brain oxygen content difference, cerebral metabolic rate for oxygen, intracranial pressure, and cerebral perfusion pressure to functional neurologic outcome in 12 comatose children on 2 consecutive days after near-drowning. Five children survived with functional neurologic outcome; five died and two survived with severe neurologic damage. Children who survived with functional neurologic outcome had a significantly higher cross-brain oxygen content difference (7.89 +/- 2.62 vs 3.91 +/- 1.59 ml/dl; p = 0.028) at 24 hours and a higher cerebral metabolic rate for oxygen 48 hours after admission (3.19 +/- 2.86 vs 0.96 +/- 0.45 ml/100 gm per minute; p = 0.030) compared with those who died or survived in a damaged state. There were no significant differences in global cerebral blood flow, intracranial pressure, and cerebral perfusion pressure between groups at either 24 or 48 hours. Our preliminary data suggest that a higher cross-brain content difference value is an important early variable associated with functional neurologic recovery after near-drowning. However, a single cross-brain oxygen content difference value must be interpreted with caution because considerable variability may occur among patient groups.
Assuntos
Encéfalo/metabolismo , Circulação Cerebrovascular , Afogamento Iminente/fisiopatologia , Doenças do Sistema Nervoso/etiologia , Consumo de Oxigênio , Adolescente , Criança , Pré-Escolar , Coma/complicações , Coma/mortalidade , Coma/fisiopatologia , Coma/terapia , Humanos , Lactente , Pressão Intracraniana , Afogamento Iminente/complicações , Afogamento Iminente/mortalidade , Afogamento Iminente/terapia , Doenças do Sistema Nervoso/epidemiologia , Fatores de Tempo , Resultado do TratamentoRESUMO
The relationship between mean arterial pressure, intracranial pressure, cerebral blood flow, cross-brain oxygen extraction, cerebral metabolic rate, and outcome was studied during therapy in nine neonates on 3 consecutive days after severe hypoxic-ischemic cerebral injury. Cross-brain oxygen extraction was significantly higher (5.06 +/- 0.5 vs 2.05 +/- 0.8 ml/dl; p = 0.012) in the five neonates who survived with normal neurologic outcome than in the four who died or sustained severe brain damage. In contrast, global cerebral blood flow in the five neonates with normal neurologic outcome was significantly lower (25.6 +/- 8.2 vs 83.2 +/- 44.9 ml/100 gm brain/min; p less than 0.05) during the study period. The differences in cross-brain oxygen extraction and global cerebral blood flow between infants who had neurologic recovery and those who died or sustained brain damage occurred in the presence of acceptable values for intracranial pressure, mean arterial pressure, and cerebral perfusion pressure. Our preliminary data suggest that cross-brain oxygen extraction and possibly global cerebral blood flow may be important variables associated with severe neuronal injury and death after hypoxic-ischemic cerebral injury.
Assuntos
Isquemia Encefálica/fisiopatologia , Encéfalo/metabolismo , Circulação Cerebrovascular/fisiologia , Hipóxia Encefálica/fisiopatologia , Pressão Intracraniana/fisiologia , Oxigênio/metabolismo , Asfixia Neonatal/complicações , Asfixia Neonatal/fisiopatologia , Isquemia Encefálica/etiologia , Humanos , Hipóxia Encefálica/etiologia , Recém-Nascido , PrognósticoRESUMO
In six deeply comatose children, the relationships of intracranial pressure, cerebral perfusion pressure, cerebral blood flow, cross-brain oxygen consumption, and metabolic rate to outcome were studied sequentially during therapy. Intracranial pressure, cross-brain oxygen consumption, and metabolic rate values were significantly different in the three children who survived compared with those in the three who died. The differences in cross-brain oxygen consumption and metabolic rate occurred in the presence of clinically acceptable values for intracranial and cerebral perfusion pressures. Cross-brain oxygen consumption and metabolic rate may be important indicators of degree of neuronal injury, and of outcome.