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An acute ischaemic stroke (AIS) is a non-specific state of brain injury with neuronal dysfunction that has several pathophysiologic causes and is time critical. More than 70% of cases are due to thrombotic or embolic causes with resultant focal ischaemia and an accompanying neurological deficit. Initial assessment, stabilization and early imaging are important aspects of effective stroke management. Over the last two decades, thrombolysis and mechanical thrombectomy have proven beneficial in reversing neurological deficits and improving functional outcomes. Guidelines now support administration of recombinant tissue plasminogen activator (rt- PA ) up to 4.5 hours and extension of thrombectomy windows up to 24 hours after onset of symptoms in a select group of patients. Other important aspects of management include administration of antiplatelet agents (aspirin) within 48 hours, management within a specialist stroke unit, and decompressive hemi-craniectomy for malignant middle cerebral artery (MCA) stroke.

This review considers important aspects in the provision of anesthesia for endovascular neurosurgery. Subject literature was reviewed to include important publications which have influenced neuro-interventional practice alongside recent meta-analyses to provide a contemporaneous evidence-based review. The scope of endovascular neurosurgery and interventional neuro-radiology continues to expand. The advancement of catheter and imaging technologies, alongside the development of novel techniques, has allowed a minimally invasive endovascular approach to be applied to pathologies previously only treatable by open surgery, and to patients previously considered unsuitable for invasive surgical approaches. This has led to increasing complexity in both the procedures performed and the patients encountered in the neuro-radiology suite. An understanding of the technical aspects, physiological requirements, and potential problems relating to each procedure is required to facilitate close cooperation between the anesthesiologist and neuro-interventional team, to provide safe and effective care.

The insertion of bolt external ventricular drains (EVD) on the intensive care unit (ICU) has enabled rapid cranial cerebrospinal fluid (CSF) diversion. However, bolt EVDs tend to be perceived as a more challenging technique, particularly when dealing with small ventricles or when there is midline shift distorting the ventricular morphology. Furthermore, if neuronavigation guidance is felt to be necessary, this usually assumes a transfer to an operating theatre. In this technical note, we describe the use of electromagnetic neuronavigation for bolt EVD insertion on the ICU and assess the protocol’s feasibility and accuracy. Case series of neuronavigation-assisted bolt EVD insertion in ICU setting, using Medtronic Flat Emitter for StealthStation EM. Neuronavigation-guided bolt EVDs were placed at the bedside in n = 5 patients on ICU. Their widest frontal ventricular horn diameter in the coronal plane ranged from 11 to 20 mm. No procedural complications were encountered. Post-procedural CT confirmed the optimal placement of the EVDs. Electromagnetic neuronavigation is feasible at the ICU bedside and can assist the insertion of bolt EVDs in this setting. The preference for a bolt EVD to be inserted in ICU—as is standard practice at this unit—should not prohibit patients from benefitting from image guidance if required.

Subarachnoid haemorrhage is an acute neurosurgical emergency affecting patients of all ages and with high mortality. It is usually caused by rupture of an aneurysm of an intracranial artery at a point of turbulent blood flow within the circle of Willis. Diagnosis should be made rapidly initially with non-contrast CT of the head. Minimizing secondary neurological injury is the focus of care. Initial stabilization focussing on providing adequate cerebral oxygenation and perfusion should be carried out expediently and this may require intubation and ventilation. Transfer to a specialist neurosciences centre for ongoing management is the next priority. Culprit aneurysms should be secured promptly by endovascular coiling or surgical clipping. Recognition and management of complications is best undertaken in a centre managing high volumes of these patients. Vasospasm is a common and feared complication of subarachnoid haemorrhage. All patients should be given nimodipine for prophylaxis and management of this complication.

Severe traumatic brain injury (TBI) is associated with significant morbidity and mortality. The critical care management of TBI requires a coordinated and comprehensive approach to treatment, including strategies to prevent secondary brain injury and maintenance of adequate cerebral perfusion and oxygenation. Management protocols have evolved with international consensus, providing guidelines that assist clinicians in delivering optimal care. Those from the Brain Trauma Foundation are continuously updated to incorporate new trial data ( https://braintrauma.org/coma/guidelines ).

Secondary brain injury has devastating effects on morbidity, mortality and good functional outcomes. Neuroprotection is multimodal, with decades of preclinical and small clinical studies showing the benefits of therapeutic hypothermia. The basic scientific principles have merit, yet large randomized controlled trials fail to show a clear benefit. This article will review the basic science the practical aspects of delivering targeted temperature management and evaluate the evidence behind its use for acute brain injuries. With a lack of high-quality evidence for hypothermia, recent consensus statements are shifting the paradigm away from hypothermia to the maintenance of normothermia and prevention of pyrexia.

The accuracy of tunneled external ventricular drain (EVD) placement has been shown to be similar among practitioners of varying experience, but this has not yet been investigated for bolt EVDs. Tunneled and bolt EVDs are distinct techniques, and it is unclear if conclusions regarding accuracy can be inferred from one method to the other. The goal of this study was to determine whether neurosurgical experience influences the accuracy of bolt EVD placement. We performed a single-center retrospective analysis of accuracy of bolt EVD placement between 1st December 2018 and 31st May 2020, comparing the accuracy outcomes between three levels of training (junior trainees (JT); mid-grade trainees (MT); senior trainees/fellows (ST)). Accuracy was determined radiologically by two methods: Kakarla grade and by measuring the distance of the catheter tip to its optimal position (DTOP) at the foramen of Monro. Eighty-seven patients underwent insertion of bolt EVDs, of which n = 19 by JT, n = 40 by MT and n = 28 by ST, with a significant difference found between training grades in the median Kakarla grade (p = 0.0055) and in the accuracy of placement as per DTOP (p = 0.0168). In contrast to previous published results on tunneled EVDs, we demonstrate that the accuracy of bolt EVD placement is dependent on neurosurgical experience. Our results draw awareness to the fact that the bolt EVD technique can represent a challenge for less experienced practitioners and underline the importance of dedicated training to support the safe insertion of bolt ventricular catheters.

Background Multimodal monitoring of intracranial pressure and brain tissue oxygen tension (PbtO2) have been increasingly used to detect delayed cerebral ischemia (DCI) after subarachnoid hemorrhage. At our center, patients who cannot be easily assessed clinically will undergo intracranial pressure and PbtO2 monitoring via a NEUROVENT-PTO bolt. We aimed to determine whether the Lindegaard ratios (LRs) computed from transcranial Doppler ultrasonography (TCDU) would correlate with, or can predict, the simultaneously recorded PbtO2 value. Methods Patients with aneurysmal subarachnoid hemorrhage, PbtO2 recordings from the middle cerebral artery territory, and simultaneous TCDU scans available from the ipsilateral middle cerebral artery and internal carotid artery from August 2018 to 2019 were included in the present study. The index test result was vasospasm (LR of ≥3) found on TCDU. The reference standard was the presence of regional hypoxia (PbtO2 Results A total of 28 patients (6 men and 22 women; age, 59.04 ± 13.75 years) were identified with simultaneous brain tissue oxygen and TCDU recordings available. Of the 28 patients, 7 had cerebral hypoxia (PbtO2 Conclusion We find TCDU to be specific for predicting cerebral hypoxia (measured via an intraparenchymal probe). Therefore, it could be a useful and noninvasive tool in the context of preventative DCI monitoring. However, given the low sensitivity, the lack of vasospasm on TCDU should not preclude the possibility of the presence of evolving DCI.

Status epilepticus (SE) it is widely recognized as the second most common and life-threatening neurological emergency after stroke, which carries a high mortality and morbidity. The main goal of treatment is to emergently stop clinical and electrographic seizure activity. Most authorities agree on three-line treatment for SE with administration of benzodiazepines followed by longer-acting anti-epileptic agents and finally, if seizures persist, the administration of general anaesthetic agents.

Neuromuscular diseases are relatively rare but it is important for both anaesthetists and intensivists to have a working knowledge of the common diseases, as they may complicate general anaesthesia and result in neurogenic respiratory failure. The most common neurological condition seen in the intensive care unit is that of critical illness neuropathy; this subject is covered elsewhere in the journal. The diseases most commonly encountered in general anaesthetic practice include motor neurone disease, Guillain-Barre syndrome, botulism, myasthenia gravis and the muscular dystrophies.

Spontaneous subarachnoid haemorrhage (SAH) is a neurovascular emergency with sudden onset, which requires rapid recognition and early treatment to minimize the occurrence of serious complications. The most common cause is a cerebral aneurysm, which develops at areas of turbulent flow, especially within the circle of Willis. Initial aims are to provide appropriate resuscitation to the patient and to maintain cerebral oxygenation and perfusion. Anaesthesia involves prompt airway control and precise management of physiological parameters to reduce further neurological injury, such as from re-bleeding or delayed cerebral ischaemia. Once stabilized SAH patients should be admitted to a neurointensive care unit and managed by a skilled multidisciplinary team. Definitive treatment then involves either endovascular coiling or surgical clipping, preferably in hospitals managing high volumes of SAH cases per year. Care should be also taken throughout to avoid non-neurological complications such as infections or venous thromboembolism.

Key points The scope of interventional neuroradiology has expanded rapidly. Conditions which were previously untreatable or only amenable to open surgical techniques are now being considered for interventional radiological management (Table 1). View this table: Table 1 Classification of interventional neuroradiological procedures Subarachnoid haemorrhage (SAH) accounts for about 5% of all strokes and may be due to congenital or acquired conditions, the most common being intracranial aneurysms. Cerebral aneurysms are present in up to 6% of the population.1 SAH requires a multi-disciplinary approach to management, at a dedicated neurosciences centre. Patients may present with sudden-onset occipital headache (‘thunder clap’). Associated features include nausea and vomiting, neck stiffness, photophobia, focal neurology, deteriorating level of consciousness, seizures, and cardiac arrest.2 Complications after an SAH include re-bleeding (5–10% in the first 72 h), obstructive hydrocephalus (incidence of 20–30% within 3 days of ictus), and vasospasm (angiographically demonstrated arterial narrowing 3–14 days after SAH). Delayed cerebral ischaemia and vasospasm may be asymptomatic and are associated with a worse outcome after SAH. The mortality rate at 7 days post-SAH is up to 40%. Other multisystem features include ECG changes (e.g. shortened PR interval, prolonged QTc interval, ST segment changes, and changes to T wave morphology), elevated cardiac enzymes, cardiogenic and neurogenic pulmonary oedema, and sodium disturbances. Patients with suspected diagnosis of SAH should have an urgent non-contrast computerized tomography (CT) scan (sensitivity of …