Though neurosciences have made great progress over the last 20 years, the optimal
place to care for the critically-ill neurologic patients remain ill-defined. Some
institutions have established specialized neurocritical care units (NCCUs), which
provide comprehensive support for patients with life-threatening neurological illnesses
by integrating the management of both the brain and the other organs simultaneously.
Admission to these NCCUs has been claimed to decrease the mortality and improve the
outcomes in the form of discharge dispositions.[1]
However, there is skepticism among the hospital administrators and some clinicians
too that neurocritical care is expensive and resource-demanding with relatively poor
outcomes. The cost effectiveness of these units remains debatable. A Finnish Intensive
Care Consortium database showed that the cost per independent survivor in an NCCU
was €58,497 for traumatic brain injury (TBI) and €96,369 for subarachnoid hemorrhage
(SAH). Acute ischemic stroke (AIS; €104,374) and intracerebral hematoma (ICH; €1,78,071)
are even more expensive.[2] An American study supports these statistics with the mean cost per survivor of intracranial
hemorrhage at $1,18,813.[3]
Apart from the cost issue, the accessibility to an NCCU is a major issue. Access to
the NCCU is limited even in the resource-rich western world.[4]
In spite of heavy costs and accessibility issues, several studies documented clinical
benefits conferred by these dedicated NCCUs. Suarez et al reported that introduction
of a neurocritical care team, including a full-time neurointensivist who coordinated
care, was associated with significantly reduced in-hospital mortality and length of
stay without change in readmission rates or long-term mortality.[5] Another recent report concluded that admission to the NCCU was a significant predictor
of increased hospital discharge with an odds ratio (OR) of 2.3 and significantly lower
ICU length of stay (LOS; 15 vs. 21.4 days) and lower ICU and hospital mortality rates
(5.3% vs. 10.2% and 9.1% vs.19.5%, respectively; p < 0.05). NCCU patients had higher discharge Glasgow Coma Score (GCS) and underwent
fewer tracheostomies.[6]
Neurological patients cared for in specialized neuro-ICUs underwent more invasive
intracranial and hemodynamic monitoring, tracheostomy, and nutritional support, and
received less intravenous (IV) sedation than patients in general ICUs. These differences
in care may explain the observed disparities in outcome between neurocritical care
and general ICU care.[7]
In individual diagnostic entities too, better results have been reported with NCCU
care. In patients with status epilepticus, NCCU care resulted in fewer antiepileptic
drugs and less vasopressor use.[8] Use of continuous video-electroencephalography (video EEG) as a part of the neonatal
neurocritical care program was associated with improved electrographic seizure detection,
decreased phenobarbital burden, and antiseizure medication use at discharge.[9]
Management in dedicated NCCUs, compared with combined neuro/general units, led to
improved quality of life, though at higher costs in TBI.[10] While overall outcomes were not significantly different between general ICUs and
NCCUs, some metrics of care were significantly better in NCCUs. In a study comprising
2,487 patients of which 1,572 and 915 were admitted prior to and after NCCU establishment,
respectively, the length of ICU stay and the number of days on ventilator were significantly
lower in NCCU patients. Critical care unit mortality was significantly lower in NCCU
patients. The mortality ratio (observed mortality/predicted mortality) was 0.34 and
48.1% patients showed good functional recovery (modified Rankin score, 0–2).[11] In a study aimed at validating risk prediction models for acute TBI and to use the
best model to evaluate the optimum location and comparative costs of neurocritical
care, the results suggested that management in a dedicated NCCU may be cost-effective
compared with a combined neuro/general critical care unit. These results support the
recommendation that all patients with severe TBI would benefit from transfer to an
NCCU in a neurosciences center, regardless of the need for surgery.[12]
Outcomes of subarachnoid hemorrhage (SAH) have also been reported to be better when
managed by a neurointensivist. In a study of 243 patients of whom 151 were managed
by a neurointensivist, univariate analysis demonstrated significantly better outcomes
for neurointensivist-managed group compared with general intensivist-managed intensive
care unit group (good outcomes, 58.3 vs. 41.0%, respectively, p = 0.01). Though multivariate logistic regression was not significant for the difference,
outcomes in SAH patients with Hunt and Kosnik grades I to II were better when managed
by the neurointensivist.[13]
Stroke units are a subset of NCCUs, which have been documented to improve the outcomes
of patients with intracranial hemorrhage (ICH) and ischemic stroke. Among 6,223 eligible
patients with ischemic stroke admitted to regional stroke centers in Ontario, the
30-day risk-adjusted mortality was lower for stroke unit care across all stroke subtypes.
In multivariate analysis, after controlling for age, gender, medical comorbidities,
and stroke severity, there was a significant reduction in stroke mortality associated
with stroke unit admission in all stroke subtypes. The results remained similar after
a sensitivity analysis excluding patients receiving palliative care. This study provides
“real-world” evidence that all ischemic stroke subtypes do benefit from a stroke unit
admission regardless of the etiology.[14] The benefits of stroke care units reported in larger tertiary centers extend to
smaller community hospitals with more limited resources. Establishing stroke care
units in a community hospital not only increases the survival of stroke patients,
but also the proportion of patients discharged home to live independently.[15]
Some limitations of NCCU admission in certain category of patients have been reported.
In a study of 3,641 patients with CT evidence of TBI, patients with TBI and multiple
injuries had lower mortality risk when admitted to a trauma ICU. This survival benefit
increased with increasing injury severity. Isolated TBI patients had similar mortality
risk when admitted to NCCU compared with those admitted to a trauma ICU.[16]
Of late, there is some evidence that it is the standardized management protocol rather
than the NCCU that improves the clinical outcomes of TBI. In a study conducted in
North American trauma centers, care in a dedicated NCCU did not improve risk-adjusted
in-hospital survival. However, the presence of a standardized management protocol
for severe TBI patients was associated with lower risk-adjusted in-hospital mortality.[17] Another study showed that mild TBI patients with a convexity SAH, small convexity
contusion, small intraparenchymal hematoma (≤ 10 mL), and/or small subdural hematoma
do not require admission to an ICU.[18]
In stroke management, combination of an organized acute stroke unit and a short-term
ward is shown to reduce the mortality and complications of ischemic stroke as well
as the length of stay when compared with the general medical ward. The results of
this study assure that the combination of a stroke unit and a short-term ward is useful
in developing countries, which have limited number of beds in their stroke units.[19] A shorter length of stay but no large differences in functional outcome, safety,
or cost is seen among patients with minor intracerebral hematomas admitted to a dedicated
stroke unit compared with those admitted to general ICUs.[20]
Thus, there is contradicting evidence regarding the need for NCCUs versus general
ICUs. The best approach to resolve the conflict of whether to admit a patient to NICU
or not is to use predictive models, of which there are not many at the moment. The
authors of one study derived a clinical tool that defined a subset of pediatric patients
with mild TBI at low risk for ICU-level care. The clinical decision rule (CDR) in
this study consisted of five predictor variables: midline shift > 5 mm, intraventricular
hemorrhage, non-isolated head injury, postresuscitation GCS score of < 15, and cisterns
absent. The CDR correctly identified 37 of 40 patients requiring ICU-level care (sensitivity
= 92.5%; 95% CI = 78.5–98.0) and 154 of 244 patients who did not require an ICU-level
intervention.[21]
Futility of care is something to be remembered while admitting certain category of
patients to the ICUs in general and NCCUs in particular. Some studies have brought
forth this issue. These studies looked at patients with poor outcome in NICU. In one
study the authors prospectively identified patients who were admitted to the NCCU
with partial loss of brainstem reflexes persisting for > 24 hours due to an intrinsic
lesion of the brain (trauma, stroke, hemorrhage, etc.). Of the total 102 patients,
72 died after a mean of 16 days and 23 remained comatose, locked-in, or in a vegetative
state. Four were conscious and followed commands, while three were minimally conscious,
episodically obeying simple commands.[22] More such predictive models should be developed to utilize the neurocritical care
resources more usefully.
In conclusion, while there is no doubt about the benefits of NCCUs, limitations and
futility in certain category of patients have to be kept in mind while admitting the
patients to this facility. More reliable data should be generated through multicenter
trials regarding the nature of patients who benefit from admission to the NCCU. Only
when we use such prudence, then only we can convince the administrators about the
investment that goes into the facility of neurocritical care which is perceived as
a white elephant.
