The critical care management of poor-grade subarachnoid haemorrhage

Abstract

Aneurysmal subarachnoid haemorrhage is a neurological syndrome with complex systemic complications. The rupture of an intracranial aneurysm leads to the acute extravasation of arterial blood under high pressure into the subarachnoid space and often into the brain parenchyma and ventricles. The haemorrhage triggers a cascade of complex events, which ultimately can result in early brain injury, delayed cerebral ischaemia, and systemic complications. Although patients with poor-grade subarachnoid haemorrhage (World Federation of Neurosurgical Societies 4 and 5) are at higher risk of early brain injury, delayed cerebral ischaemia, and systemic complications, the early and aggressive treatment of this patient population has decreased overall mortality from more than 50 % to 35 % in the last four decades. These management strategies include (1) transfer to a high-volume centre, (2) neurological and systemic support in a dedicated neurological intensive care unit, (3) early aneurysm repair, (4) use of multimodal neuromonitoring, (5) control of intracranial pressure and the optimisation of cerebral oxygen delivery, (6) prevention and treatment of medical complications, and (7) prevention, monitoring, and aggressive treatment of delayed cerebral ischaemia. The aim of this article is to provide a summary of critical care management strategies applied to the subarachnoid haemorrhage population, especially for patients in poor neurological condition, on the basis of the modern concepts of early brain injury and delayed cerebral ischaemia.

Assessment of a multi-layered diffuse correlation spectroscopy method for monitoring cerebral blood flow in adults

“…Patients requiring intensive care due to life-threatening neurological emergencies, such as ischemic stroke, traumatic brain injury and subarachnoid hemorrhage, are at high risk of secondary brain injury [1][2][3]. Although multiple factors contribute to poor outcome, a major focus is preventing delayed cerebral ischemia.…”

Management of raised intracranial pressure in aneurysmal subarachnoid hemorrhage: time for a consensus?

“…18 In fact, elevated ICP is known to be a significant contributor to secondary brain injury following aneurysm rupture and is an independent predictor of poor functional outcome and increased mortality. 51,74 In addition, surgical securing of ruptured aneurysms has been shown to be more complicated when cerebral edema is present.…”

“…Since the majority of patients with aSAH either present with hydrocephalus or develop it at some point during their hospital stay, external ventricular drains (EVDs) are most commonly used both to monitor and manage elevated ICP via CSF drainage if needed. 18 It is for the latter reason that parenchymal pressure monitors are rarely used in aSAH as they do not allow therapeutic CSF drainage. 66 EVDs can also assist in determining if there is a need for permanent CSF diversion such as via insertion of a ventriculoperitoneal shunt.…”

“…In the setting of aSAH, parameters such as fluid balance, blood pressure, serum sodium, and serum osmolality must be managed carefully to prevent secondary injury and reduce the risk of vasospasm/DCI. 18 Furthermore, current guidelines recommend euvolemia and hypertensive therapy in the setting of DCI. 14 The optimal hyperosmolar agent to lower raised ICP in aSAH is contentious.…”

“…On the other hand, fever, which is common after aSAH, is an independent predictor of poor outcome. 18 Higher temperatures induce an acute-phase reaction that leads to an increased cerebral metabolic distress (e.g., release of excitatory amino acids such as glutamate, creation of free radicals, and elevated lactate/pyruvate ratio). 48,54,65 Therefore, it appears there must be a middle ground whereby the adverse effects of both temperature extremes can be balanced.…”