Delivery of heliox with a semi-closed circuit during spontaneous breathing: a comparative economic theoretical study

Neonatal Applications of Heliox: A Practical Review

Heliox is a mixture of helium and oxygen that may be utilized as an alternative to air-oxygen during the ventilatory support in the neonate. Special physical properties of Heliox, particularly low density, allow for improved gas flow and diffusion. First reports of Heliox use in the pediatric population were published in 1930s; however, this therapy has never gained widespread popularity despite its described beneficial effects. Historically, this was largely due to technical challenges associated with Heliox ventilation that significantly limited its use and realization of large-scale clinical trials. However, nowadays several commercially available ventilators allow easy and safe ventilation with both conventional and non-invasive modes. In the era of minimally invasive respiratory interventions in the newborn Heliox could be seen as a therapy that may potentially decrease the risk of non-invasive ventilation failure. This review presents pathophysiologic rationale for the use of Heliox in the newborn, and summarizes available data regarding applications of Heliox in the setting of neonatal intensive care unit based on clinical studies and findings from animal models. Mechanisms of action and practical aspects of Heliox delivery are thoroughly discussed. Finally, future research directions for neonatal use of Heliox are proposed.

Administration of inhaled noble and other gases after cardiopulmonary resuscitation: A systematic review

OBJECTIVE

Inhalation of noble and other gases after cardiac arrest (CA) might improve neurological and cardiac outcomes. This article discusses up-to-date information on this novel therapeutic intervention.

DATA SOURCES

CENTRAL, MEDLINE, online published abstracts from conference proceedings, clinical trial registry clinicaltrials.gov, and reference lists of relevant papers were systematically searched from January 1960 till March 2019.

STUDY SELECTION

Preclinical and clinical studies, irrespective of their types or described outcomes, were included.

DATA EXTRACTION

Abstract screening, study selection, and data extraction were performed by two independent authors. Due to the paucity of human trials, risk of bias assessment was not performed DATA SYNTHESIS: After screening 281 interventional studies, we included an overall of 27. Only, xenon, helium, hydrogen, and nitric oxide have been or are being studied on humans. Xenon, nitric oxide, and hydrogen show both neuroprotective and cardiotonic features, while argon and hydrogen sulfide seem neuroprotective, but not cardiotonic. Most gases have elicited neurohistological protection in preclinical studies; however, only hydrogen and hydrogen sulfide appeared to preserve CA1 sector of hippocampus, the most vulnerable area in the brain for hypoxia.

CONCLUSION

Inhalation of certain gases after CPR appears promising in mitigating neurological and cardiac damage and may become the next successful neuroprotective and cardiotonic interventions.