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(BQ) Part 2 book Pediatric critical care medicine (Volume 2: Care of the critically ill or injured child) includes: Resuscitation, stabilization and transport of the critically ill or injured child; monitoring the critically ill or injured child; special situations in pediatric critical care medicine.
Part III Resuscitation, Stabilization, and Transport of the Critically Ill or Injured Child Vinay Nadkarni Post-resuscitation Care 25 Monica E Kleinman and Meredith G van der Velden Abstract Pediatric cardiac arrest is an infrequent but potentially devastating event While return of spontaneous circulation (ROSC) is the immediate objective, the ultimate goal is survival with meaningful neurologic outcome Once a perfusing rhythm is established, the pediatric cardiac arrest victim requires expert critical care to optimize organ function, prevent secondary injury, and maximize the child’s potential for recovery Common post-resuscitation conditions include acute lung injury, myocardial dysfunction, hepatic and renal insufficiency, and hypoxic-ischemic encephalopathy This constellation is described by the term “post-cardiac arrest syndrome” and resembles the systemic inflammatory response seen in sepsis or major trauma Children may have single organ failure or multi-organ dysfunction, and the need for critical care therapies may delay accurate evaluation of neurologic status and limit prognostic ability Pediatric post-resuscitation therapies are not typically evidencebased given the paucity of randomized trials and heterogeneous nature of the patient population Goals of care include normalizing physiologic and metabolic status, preventing secondary organ injury, and diagnosing and treating the underlying cause of the arrest Therapeutic hypothermia has been shown to mitigate the severity of brain injury for adults following sudden arrhythmia induced cardiac arrest and neonates following resuscitation from hypoxic-ischemic encephalopathy at birth, but the role of targeted temperature control in pediatric post-arrest care is an area of active investigation There is no single diagnostic test or set of criteria to accurately predict neurologic outcome, providing a challenging situation for critical care specialists and families alike Keywords Resuscitation • Cardiac arrest • Critical care • Organ dysfunction • Post-cardiac arrest syndrome • Reperfusion • Brain injury Introduction M.E Kleinman, MD (*) Division of Critical Care Medicine, Department of Anesthesiology, Children’s Hospital Boston, 300 Longwood Avenue, Bader 634, Boston, MA 02115, USA e-mail: monica.kleinman@childrens.harvard.edu M.G van der Velden, MD Department of Anesthesia, Children’s Hospital Boston, 300 Longwood Avenue, Bader 634, Boston, MA 02115, USA e-mail: meredith.vandervelden@childrens.harvard.edu D.S Wheeler et al (eds.), Pediatric Critical Care Medicine, DOI 10.1007/978-1-4471-6362-6_25, © Springer-Verlag London 2014 The immediate objective of pediatric cardiopulmonary resuscitation is return of spontaneous circulation (ROSC), while the ultimate goal is survival with a favorable neurologic outcome Once a perfusing rhythm is established, the pediatric cardiac arrest victim requires critical care focused to optimize organ function, prevent secondary injury, and maximize the child’s potential for recovery Common postresuscitation conditions include acute lung injury, myocardial dysfunction, hepatic and renal insufficiency, and 271 272 Post-cardiac Arrest Syndrome Recent advances in the understanding of pathophysiologic events following return of circulation have led to the description of the “post-cardiac arrest syndrome” [19] This condition is characterized by myocardial dysfunction, neurologic impairment, and endothelial injury that resemble inflammatory conditions such as sepsis (capillary leak, fever, coagulopathy, vasodilation) The series of events during reperfusion can be divided into four phases: (1) immediate (first 20 after ROSC); (2) early post-arrest (20 through 6–12 h after resuscitation); (3) intermediate phase (6–12 h through 72 h post-arrest); and (4) recovery phase (beyond 72 h) Some experts have included a fifth phase, that of rehabilitation after discharge from an acute care setting (Fig 25.1) Pathophysiology of the Post-arrest Reperfusion State The post-cardiac arrest syndrome results from two distinct but serial events – a period of ischemia, during which cardiac output and oxygen delivery are profoundly compromised, followed by a period of tissue and organ reperfusion At the time of cardiac arrest, oxygen extraction increases in an effort to compensate for reduced delivery As demand rapidly exceeds supply, tissue hypoxia triggers anaerobic metabolism and lactate production At the cellular level, hypoxia limits oxidative phosphorylation and mitochondrial ATP production As a result, ATP-dependent membrane functions such as maintenance of ion gradients begin to fail Phase Goals ROSC Immediate Intermediate 72 h Recovery Disposition Rehabilitation Prevent Recurrence 6–12 h Prognostication Early Limit ongoing injury Organ support 20 Rehabilitation seizures/encephalopathy The extent of neurologic injury may be initially difficult to assess due to multi-organ system failure following hypoxia-ischemia and reperfusion In the pediatric intensive care unit (PICU), the most common cause of death following admission after cardiac arrest is hypoxicischemic encephalopathy [1, 2], which is also responsible for the most significant morbidity in survivors Considerations for post-resuscitation care are impacted by whether the resuscitation occurs out-of-hospital or inhospital, since the epidemiology and etiology for pediatric cardiac arrest differ in these settings Out-of-hospital arrest is more likely to be asphyxial in origin, in which cardiac arrest is the end result of progressive hypoxia and ischemia Multiple cohort studies of out-of-hospital pediatric cardiac arrests have found that most were of respiratory origin [3–12] A recent report from 11 North American sites participating in the Resuscitation Outcomes Consortium (ROC) found that the incidence of non-traumatic out-of-hospital cardiac arrest in patients 300 mmHg, had a higher in-hospital mortality compared with patients who were normoxic (PaO2 60–300 mmHg) or hypoxic (PaO2