High flow nasal cannula (HFNC) with Heliox decreases diaphragmatic injury in a newborn porcine lung injury model

Abstract

Background High flow nasal cannula (HFNC) improves ventilation by washing out nasopharyngeal dead space while delivering oxygen. Heliox (Helium-oxygen gas mixture), a low density gas mixture, decreases resistance to airflow, reduces the work of breathing and facilitates distribution of inspired gas. Excessive lung work and potential injury increases the workload on the immature diaphragm predisposing the muscle to fatigue and can lead to inflammatory and oxidative stress, thereby contributing to impaired diaphragmatic function. We tested the hypothesis that HFNC with Heliox will decrease the work of breathing thereby unloading the neonatal diaphragm and potentially reducing diaphragmatic injury. Methods Spontaneously breathing neonatal pigs were randomized to Nitrox (Nitrogen-oxygen gas mixture) or Heliox and studied over 4 hrs following oleic acid injury. Gas exchange, pulmonary mechanics indices and systemic markers of inflammation were measured serially. Diaphragm inflammation biomarkers and histology for muscle injury were assessed at termination. Results Heliox breathing animals demonstrated decreased respiratory load and work of breathing with lower pressure- rate product, lower labored breathing index, and lower levels of diaphragmatic inflammatory markers and muscle injury score as compared to Nitrox. Conclusion These results suggest that HFNC with Heliox is a useful adjunct to attenuate diaphragmatic fatigue in the presence of lung injury by unloading the diaphragm, resulting in a more efficient breathing pattern and decreased diaphragm injury.

Effects of heliox and non-invasive neurally adjusted ventilatory assist (NIV-NAVA) in preterm infants

“…A study in an animal model found that increased diaphragm load, expressed by high voltage Edi max , is associated with damage to its sarcomeres 25 . In a porcine model of acute lung injury, high flow nasal cannula (HFNC) with heliox demonstrated a protective effect towards the diaphragm 26 . The significant and rapid decrease of Edi voltage after introduction of heliox suggests that the change of breathing mixture to heliox has direct influences on respiratory function.…”

Neonatal Applications of Heliox: A Practical Review

“…Heliox ventilation was reported to reduce respiratory effort, diaphragmatic load and display protective effects against atelectasis and airway collapse. In addition, it facilitates the distribution of respiratory gases in narrow and/or constricted airways (17, [23][24][25]. Helium-oxygen may allow better penetration into the peripheral parts of the lungs and improve ventilation/perfusion ratio.…”

“…Another modality of respiratory support that was shown to be safe and more effective than standard oxygen therapy in infants with bronchiolitis is high flow nasal cannula (HFNC) ( 37 , 38 ). Considering this fact and encouraging results of a study in which HFNC with Heliox utilized in animal models of lung injury resulted in reduced work or breathing and less lung inflammation it seems that helium-oxygen high flow therapy may be an interesting alternative to nCPAP ( 24 ). There was an attempt to assess Heliox HFNC in bronchiolitis in an American trial that was terminated in 2019 (NCT02373683).…”

Skeletal dysplasia: Respiratory management during infancy

“…Preclinical evidence suggests that heliox combined with high-flow nasal cannula decreases work of breathing and attenuates diaphragmatic injury and fatigue [63]. The role of heliox in infants with skeletal dysplasia and airway obstruction is yet to be explored and holds potential.…”