Pediatric in-hospital cardiac arrest (IHCA) is a rare event with possible devastating consequences. It is considered a major public healthcare problem. Thanks to advances in cardiopulmonary resuscitation (CPR) guidelines and teaching skills, results in children have improved [1, 2]. However, pediatric CA still has a very high mortality [3,4,5].
Survival to pediatric IHCA has been related to multiple factors. Previous studies have described the influence of patient characteristics, quality of CPR, post-resuscitation factors and team interventions in mortality [3, 4, 6,7,8]. Current recommendations on CPR have insisted on the importance of quality and post-resuscitation care in an attempt to improve outcomes . However, in the treatment of in-hospital CA there are still multiple controversies and gaps of knowledge.
Some clinical and experimental studies have suggested that quality of cardiopulmonary resuscitation (frequency and depth of chest compressions, compression-decompression ratio, coordination of chest compressions and ventilation with coordination of rescuers) is associated with better CPR results .
Ventilation for pediatric CA
In the last decade, some authors have suggested that initial basic CPR with only chest compressions may be equal to or better than providing chest compressions plus ventilation. In contrast, clinical studies in children  and experimental studies in child animal models  have shown that early ventilation and oxygenation are essential in child CPR. Intubation during CPR has for many years been considered an essential maneuver during advanced CPR, as it achieves safe isolation of the airway and allows good ventilation. However, intubation is a technique that requires learning and training and can be difficult to perform in emergency situations such as a CA. In recent years, several studies in adults and children have suggested that intubation during CPR is associated with a worse survival and neurological prognosis [13, 14], but a recent large study in adults does not confirm these results . There are no controlled, experimental, descriptive or clinical studies that have looked at this problem.
Once ROSC is achieved, efforts towards survival have to assess and treat post-cardiac arrest syndrome. Outcomes in terms not only of survival, but of good neurological outcome, depend on various factors, including hemodynamics, ventilation and oxygenation, temperature control, sedation and analgesia.
Hypotension after ROSC is associated with a worse prognosis. The ILCOR group recommends keeping systolic blood pressure (BP) above the 5th percentile, but there are no studies that assess which is the best BP in the post-resuscitation period or whether treating low blood pressure influences outcomes .
Several studies in adults and children have analyzed the influence of ventilation and oxygenation after ROSC on prognosis. Although the results between all the studies are not in agreement, most suggest that both hypoventilation and hyperventilation are associated with a worse prognosis . Hypoxia can also be a poor prognostic indicator, while the results with hyperoxia are contradictory .
Hyperthermia after ROSC is common and is associated with a worse neurological prognosis, which increases with each degree of body temperature above 37 °C. Experimental studies in animals have demonstrated the neuroprotective effect of hypothermia. Initial studies in adults found that hypothermia improved the neurological prognosis in patients recovered from CA. However, the most recent studies in adults and children have found that therapeutic hypothermia is not associated with a better neurological prognosis or longer survival . Therefore, at the present time, strict temperature control and avoiding hyperthermia are recommended.
Sedation and analgesia are fundamental in caring for the critical care child. They enable anxiety and pain treatment as well as shivering control for temperature management. However, after CA its use can difficult neurological assessment, and to date, no study has been able to describe the influence of different analgosedation protocols in neurological outcomes.
Rational for the study
For the past years, the International Liaison Committee on Resuscitation (ILCOR) has endeavored its efforts in the identification of these gaps of knowledge and their resolution. There are few clinical data to verify the efficacy of CPR interventions in the pediatric population. Thus, the development of collaborative multicenter studies is needed. The objective of this study is to develop a multicenter and international registry of in-hospital pediatric cardiac arrest including the diversity of management in different clinical and social contexts. Participation in this register will enable the evaluation of the diagnosis of CA, CPR and post-resuscitation care and its influence in survival and neurological prognosis.