An overview of management of intracranial hypertension in the intensive care unit

Abstract

Intracranial hypertension (IH) is a clinical condition commonly encountered in the intensive care unit, which requires immediate treatment. The maintenance of normal intracranial pressure (ICP) and cerebral perfusion pressure in order to prevent secondary brain injury (SBI) is the central focus of management. SBI can be detected through clinical examination and invasive and non-invasive ICP monitoring. Progress in monitoring and understanding the pathophysiological mechanisms of IH allows the implementation of targeted interventions in order to improve the outcome of these patients. Initially, general prophylactic measures such as patient's head elevation, fever control, adequate analgesia and sedation depth should be applied immediately to all patients with suspected IH. Based on specific indications and conditions, surgical resection of mass lesions and cerebrospinal fluid drainage should be considered as an initial treatment for lowering ICP. Hyperosmolar therapy (mannitol or hypertonic saline) represents the cornerstone of medical treatment of acute IH while hyperventilation should be limited to emergency management of life-threatening raised ICP. Therapeutic hypothermia could have a possible benefit on outcome. To control elevated ICP refractory to maximum standard medical and surgical treatment, at first, high-dose barbiturate administration and then decompressive craniectomy as a last step are recommended with unclear and probable benefit on outcomes, respectively. The therapeutic strategy should be based on a staircase approach and be individualized for each patient. Since most therapeutic interventions have an uncertain effect on neurological outcome and mortality, future research should focus on both studying the long-term benefits of current strategies and developing new ones.

Keywords: Cerebral perfusion pressure; Intracranial hypertension; Intracranial pressure; Neurocritical care; Osmotic agents; Traumatic brain injury.

Fig. 1

Causal relationship between primary brain injury, intracranial hypertension and secondary brain injury

Fig. 2

Types of brain herniation. ACA: Anterior cerebral artery, PCA: Posterior cerebral artery

Fig. 3

Staircase therapeutic approach of intracranial hypertension. An optimal therapeutic strategy is considered the step-by-step escalation of available interventions [29, 129], tailored for each patient. The primary goal is to maintain ICP below 22 mmHg and CPP above 60 mmHg [3]. Initially, general prophylactic measures should be applied immediately to all patients with suspected IH. Based on specific indications and conditions, surgical resection of mass lesions [48] and CSF drainage [3, 48, 69] should be considered as an initial treatment for lowering ICP. The following steps in turn include hyperosmolar therapy (mannitol or hypertonic saline) [3], which represents the cornerstone of medical treatment of acute IH, hyperventilation and therapeutic hypothermia [107, 108]. Τo control elevated ICP refractory to maximum standard medical and surgical treatment, at first, high-dose barbiturate administration [3] and then decompressive craniectomy [3, 48, 69] as a last step are recommended. This staircase therapeutic approach is based mainly on clinical experience rather than on strong published evidence. ICP: Intracranial pressure, CPP: Cerebral pressure perfusion, IH: Intracranial hypertension, CSF: Cerebrospinal fluid, BP: Blood pressure