Neurological injuries are common contributors to pediatric intensive care unit deaths: A wake-up call*

Brain injury in children is a major public health problem. In fact, acquired brain injury from hypoxia–ischemia and trauma are two of the leading causes of acquired disability and death in childhood (1, 2). Remarkably, five times more children will die of brain injuries than from all forms of childhood cancer combined (1, 3, 4). Furthermore, hypoxia–ischemia and traumatic brain injury are only a part of the constellation of neurologic injuries that lead to neurologic system failure ultimately contributing to morbidity and mortality in critically ill children. In this issue of Pediatric Critical Care Medicine, Au et al (5) documented the prevalence of neurologic injuries among patients who died while on their pediatric critical care service over a 22-month period (excluding cardiac intensive care unit patients). These authors performed an impressive review of nearly 5000 charts and established that brain injury and neurologic system failure were common and often contributed to these children's deaths. Notably, the overall mortality rate was 1.6% (78 deaths per 4694 admissions). Of the 78 deaths, they attributed the “proximate cause of death” for 51 patients (65%) to “brain injury” (herniation, hypoxic–ischemic injury, hemorrhage, and/or trauma). The 51 patients with brain injury were stratified into patients with “admission brain injury” (78%) or patients who “acquired brain injury” after hospitalization (22%) and also stratified by health status before hospitalization (previously healthy [55%] vs. chronically ill [45%]). The “precipitating causes” of the brain injuries were predominantly cardiac arrest and/or respiratory arrest (65% [15 of 23]) in chronically ill patients and trauma (53% [15 of 28]) in previously healthy children. Au and colleagues concluded that brain injury was the most common “proximate” cause of death in children admitted to their pediatric intensive care unit, and their data demonstrate some of the complexities regarding attribution of cause of death and “proximate cause of death.” For example, Table 2 shows that cardiac arrest, respiratory arrest, and intracranial bleeding while anticoagulated on extracorporeal support were the “precipitating cause of brain injury” for 24 of 51 (47%) of the children whose “proximate” cause of death was attributed to neurologic injury. Furthermore, technologic support was withdrawn for 52 of 78 (67%) of these children who died. Most of these withdrawals (33 of 52 [63%]) were the result of “neurologic futility,” yet 19 of 52 (37%) were for other reasons. Should the causes of death and “proximate causes of death” be attributed to the diseases that led to the cascade of events associated with their death (eg, respiratory failure, cardiac failure, sepsis, traumatic brain injury, as in Table 1) or to the resultant brain injuries or to withdrawal of technologic support? It seems reasonable to conclude that these children died from a complex set of problems and that brain injuries were important contributing factors in the multifactorial pathway to death among most of these children. Why is this important? As intensivists, we need to understand the factors that have contributed to our patients' bad outcomes (eg, deaths) in the past so that we can improve the outcomes of our patients in the future. Although we might debate the definitions and attributions of the causes of death, the observations by these investigators clearly provide a “wake-up call” for intensivists and support the need for research and development of neuroprotective strategies for critically ill children. Such strategies should include novel neuroprotective strategies for severe brain injuries late in the cascade toward death. More importantly, the data from this study highlight the need for prevention and treatment of secondary neurologic injuries that begin further upstream in this cascade. The latter neuroprotective strategies often require initiation early in critical illnesses of differing pathologies and may need to be “personalized” and pathology-specific. These strategies include implementation of simple and effective resuscitation principles such as prevention, recognition, and aggressive management of respiratory failure, shock, and cardiac arrest. For example, more than half of these patients (43 of 78) had cardiac arrests. Perhaps the most important neuroprotective strategy for these patients is prevention of the cardiac arrest and, nearly as important is prompt, high-quality cardiopulmonary resuscitation. Au and colleagues raised another important question: If neurologic injury is common in critically ill pediatric patients who subsequently die, will further subspecialization among pediatric intensivists and improved collaboration with a multidisciplinary, neurofocused team (pediatric neurologists, neurosurgeons, and physical medicine and rehabilitation) improve survival and reduce morbidity? First and foremost, there is no question that multidisciplinary basic and clinical pediatric neurocritical care investigations will provide the foundation for improved care and better outcomes. The quality and rigor of investigation today will determine the clinical outcomes of tomorrow. Second, greater collaboration with multidisciplinary neurofocused clinicians is an obvious recipe for better care. In addition, specialized dedicated neurointensive care teams have been shown to improve outcomes of adults with severe neurologic injuries and illnesses, especially for primary neurologic processes such as intracerebral hemorrhage (6, 7). Conversely, the data from this article highlight the importance of integrating clinical neurocritical care with cardiovascular and respiratory critical care; for many of these patients, the most effective neurocritical care interventions would have included prevention and/or optimal treatment of respiratory failure, shock, and cardiac arrest. In summary, these authors have shown that brain injuries are a common contributing factor for many pediatric intensive care unit deaths. In our opinion, this is a “wake-up call” for the pediatric critical care community. We have the collective responsibility to advocate for better understanding, recognition, prevention, and treatment of neurologic injuries in the critically ill child. Todd J. Kilbaugh, MD Jimmy W. Huh, MD Robert A.