RESUMEN
The ischemic threshold is reached when the availability of oxygen in the cerebral tissue does not cover oxygen requirement. For a patient sedated, with constant PaO(2) and haemoglobin, the cerebral blood flow (CBF) global and local is the essential factor to maintain such a balance. At a cellular level, ischemia occurs when the CBF is below 20-25 ml/min. However, this threshold probably varies with the patient and also within the normal or perilesional tissue. A cerebral perfusion pressure (CPP) of 60 mmHg, recommended for a cerebral perfusion allowing a sufficient CBF for normal brain, does not prevent ischemia. Monitoring aimed to control parameters of the aerobic metabolism (PtiO(2), SjO(2) and microdialysis) and to detect the ischemic threshold allows to adapt the CPP to each patient and continuously.
Asunto(s)
Isquemia Encefálica/metabolismo , Isquemia Encefálica/diagnóstico , Circulación Cerebrovascular/fisiología , Humanos , Microdiálisis , Oxígeno/sangre , Consumo de OxígenoRESUMEN
Decompressive craniectomy was purposed for the treatment of refractory intracranial hypertension after head injury. This review discusses results obtained by this surgery in severe head trauma. Several studies have confirmed a reduction in intracranial pressure secondary to decompressive craniectomy. Mortality decreased and the proportion of good outcome of the survivors increased. These results have not been confirmed prospectively, and indications have to be clarified. The positive effects of decompressive craniectomy compared to barbiturate or hypocapnia in the "second tier therapy" in refractory intracranial hypertension could be interesting to evaluate.
Asunto(s)
Traumatismos Craneocerebrales/cirugía , Craneotomía , Descompresión Quirúrgica , Hipertensión Intracraneal/cirugía , Procedimientos Neuroquirúrgicos , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/fisiopatología , Humanos , Hipertensión Intracraneal/etiología , Hipertensión Intracraneal/fisiopatología , PronósticoRESUMEN
Spontaneous subarachnoidal haemorrhage can be associated with neurogenic pulmonary oedema and cardiogenic shock. The presentation is an ischemic myocardial dysfunction associated with normal coronary arteries. Hypoxaemia associated with arterial hypotension on patients with brain injury can worsen neurological outcome. The administration of norepinephrine associated with fluid expansion could be deleterious on cardiac function. We report the case of a patient with acute pulmonary oedema associated with post-aneurysmal subarachnoid haemorrhage managed with transoesophageal Doppler monitoring.