Heliox: Airway resistance

Clinical - Respiratory/Pulmonary

Note that in laminar flow, Heliox offers no advantages, as it has approximately the same viscosity as air. Also note that Heliox is ~ 70% helium, thus the potential benefit of improved gas flow must be balanced by the knowledge that a lower FiO2 may be delivered

Heliox: Summary

  • ~ 70% helium, ~ 30% oxygen
  • Significantly less dense than air (0.5 vs 1.2 5g/L), but viscosity is about the same
  • Improves gas flow by lowering Reynold’s number (converting to laminar flow) or decreasing resistance when flow is turbulent (lower density)


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