Neuro-critical care versus general critical care for neurological injury: Beneficial evidence

INTRODUCTION

In many parts of the world, patients with neurological injury requiring critical care are managed in one of three models of intensive care; General Intensive Care Units (GICU) without direct neurosurgical/neurological input, ICUs co-located with a neuroscience unit, which may be a mixed speciality GICU with direct input from neuroscience specialists or a stand-alone Neuro-ICU (NICU) embedded within a neuroscience unit. Thus, it would be useful to start with a definition of neuro-critical care as opposed to critical care. Smith and Menon[1] provide a good definition in their chapter in the new Guide to the Provision of a Critical Care Service (GPICS) document from the Intensive Care Society:

“Neuro-critical care is devoted to the comprehensive care of critically ill patients with neurological or neurosurgical disease. Care of such patients requires an understanding of the physiology and pathophysiology common to brain diseases in general, as well as the skills and knowledge to treat a range of specific conditions. Given the exquisite vulnerability of the injured brain to physiological insults, optimal care of such patients also demands meticulous attention to maintenance of systemic and cerebral physiological targets while ensuring appropriate protection of extra-cranial organs.”

In 2004 Smith[2] asked the question “Neuro-critical care: Has it come of age?” In his conclusion, he noted that available data suggest that outcomes in neuro-specific ICUs might be better than in GICUs. He also states that we need to demonstrate this conclusively and show why. More than 10 years later can we answer this question more conclusively and for all areas of neurologic injury? Kramer and Zygun in 2011[3] and again in 2014[4] asked similar questions. Both times, they concluded that the body of evidence is strongly supporting the case for better outcomes but that there is still much to understand as to the how and why. In 2015, Smith and Menon briefly review the evidence in the GPICS[1] document and comment that it now seems clear that the care does not necessarily need to be in a single speciality unit NICU, but more importantly that multidisciplinary expertise in the care of the sick brain is available directly to the patient.

Neuro-critical care is a relatively newly recognised and emerging area of sub-speciality care, although it has been a recognised speciality for training and accreditation in the USA since the early 2000’s. Its origins come from critical care units developing within neuroscience centres, to care initially for severe traumatic brain injury (STBI), subarachnoid haemorrhage (SAH) and postoperative neurosurgical patients. Most have now expanded to also include both neurological and neurosurgical life-threatening disease such as intra-cerebral haemorrhage (ICH), ischaemic stroke, neuromuscular diseases, refractory status epilepticus and central nervous system infections. There is currently much literature about this subject, with the majority coming from North America. Many of them are single centre studies with historical controls, with few multicentre prospectively controlled studies. There is evidence of the benefits of specialist critical care for the most of the above diseases, which I have briefly summarised in the separate sections below.

• REFERENCES

• 1 Smith M, Menon D. Neurocritical care. In: GPICS 2015. London: ICS and FICM; 2015
• 2 Smith M. I. Neurocritical care: Has it come of age? Br J Anaesth 2004; 93: 753-5
• 3 Kramer AH, Zygun DA. Do neurocritical care units save lives? Measuring the impact of specialized ICUs. Neurocrit Care 2011; 14: 329-33
• 4 Kramer AH, Zygun DA. Neurocritical care: Why does it make a difference?. Curr Opin Crit Care 2014; 20: 174-81
• 5 Patel HC, Bouamra O, Woodford M, King AT, Yates DW, Lecky FE. Trauma Audit and Research Network. Trends in head injury outcome from 1989 to 2003 and the effect of neurosurgical care: An observational study. Lancet 2005; 366: 1538-44
• 6 National Institute for Clinical Excellence. Guidance CG56. Head Injury: Triage, Assessment, Investigation and Early Management of Head Injury in Infants, Children and Adults (Updated version 2014). 2007 Available from: https://www.nice.org.uk/guidance/cg176
• 7 Harrison DA, Prabhu G, Grieve R, Harvey SE, Sadique MZ, Gomes M. et al. Risk adjustment in neurocritical care (RAIN) – Prospective validation of risk prediction models for adult patients with acute traumatic brain injury to use to evaluate the optimum location and comparative costs of neurocritical care: A cohort study. Health Technol Assess 2013; 17: vii-viii 1–350
• 8 English SW, Turgeon AF, Owen E, Doucette S, Pagliarello G, McIntyre L. Protocol management of severe traumatic brain injury in intensive care units: A systematic review. Neurocrit Care 2013; 18: 131-42
• 9 Teig M, Smith M. Where should patients with severe traumatic brain injury be managed? All patient should be managed in a neurocritical care unit. J Neurosurg Anesthesiol 2010; 22: 357-9
• 10 Diringer MN, Edwards DF. Admission to a neurologic/neurosurgical intensive care unit is associated with reduced mortality rate after intracerebral hemorrhage. Crit Care Med 2001; 29: 635-40
• 11 Mirski MA, Chang CW, Cowan R. Impact of a neuroscience intensive care unit on neurosurgical patient outcomes and cost of care: Evidence-based support for an intensivist-directed specialty ICU model of care. J Neurosurg Anesthesiol 2001; 13: 83-92
• 12 Damian MS, Ben-Shlomo Y, Howard R, Bellotti T, Harrison D, Griggs K. et al. The effect of secular trends and specialist neurocritical care on mortality for patients with intracerebral haemorrhage, myasthenia gravis and Guillain-Barré syndrome admitted to critical care: An analysis of the Intensive Care National Audit & Research Centre (ICNARC) national United Kingdom database. Intensive Care Med 2013; 39: 1405-12
• 13 Mendelow AD, Gregson BA, Rowan EN, Murray GD, Gholkar A, Mitchell PM. STICH II Investigators. Early surgery versus initial conservative treatment in patients with spontaneous supratentorial lobar intracerebral haematomas (STICH II): A randomised trial. Lancet 2013; 382: 397-408
• 14 Rincon F, Mayer SA. Neurocritical care: A distinct discipline?. Curr Opin Crit Care 2007; 13: 115-21
• 15 Samuels O, Webb A, Culler S, Martin K, Barrow D. Impact of a dedicated neurocritical care team in treating patients with aneurysmal subarachnoid hemorrhage. Neurocrit Care 2011; 14: 334-40
• 16 McNeill L, English SW, Borg N, Matta BF, Menon DK. Effects of institutional caseload of subarachnoid hemorrhage on mortality: A secondary analysis of administrative data. Stroke 2013; 44: 647-52
• 17 Chang TR, Kowalski RG, Carhuapoma JR, Tamargo RJ, Naval NS. Impact of case volume on aneurysmal subarachnoid hemorrhage outcomes. J Crit Care 2015; 30: 469-72
• 18 Bershad EM, Feen ES, Hernandez OH, Suri MF, Suarez JI. Impact of a specialized neurointensive care team on outcomes of critically ill acute ischemic stroke patients. Neurocrit Care 2008; 9: 287-92
• 19 Suarez JI. Outcome in neurocritical care: Advances in monitoring and treatment and effect of a specialized neurocritical care team. Crit Care Med 2006; 34 (Suppl. 09) Suppl S232-8
• 20 Kramer AH, Zygun DA. Declining mortality in neurocritical care patients: A cohort study in Southern Alberta over eleven years. Can J Anaesth 2013; 60: 966-75
• 21 Tweedie IE, Andrzejowski J. Neurocritical care. Crit Eye. 2015: 16-7