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Helium..in Birthday balloons and in Medicine

Helium is the second most abundant element in the universe (that’s cool)! It is an inert gas that is odorless and tasteless. It has a lower molecular weight and is less dense than Oxygen. It has been used in medicine since the 1930’s.It is used as integral part of HELIOX and for  inflation of Intra aortic Ballon  Pumps(IABs)..

 
In Heliox :





Heliox is a mixture of oxygen and Helium resulting in a gas less dense than air (essentially Helium replaces Nitrogen in the air). In conditions where there is increased airway resistance (asthma, croup, upper airway masses, etc) there is turbulent airflow, which increases the work of breathing. Heliox can reduce airway resistance by increasing laminar airflow and decrease work of breathing.   

 
It is generally administered in mixtures of 70:30 or 80:20 (Helium:Oxygen).
 
Potential Benefits: 
Better lung mechanics
Improved delivery of albuterol or other nebulized medications
Few known side-effects/complications (it is inert after all)
 
Drawbacks:
Expensive
Contraindicated in hypoxemic patients (if your patient needs 50% oxygen, you can’t use Heliox)
Paucity of large prospective randomized trials to support its use
It doesn’t treat the causative issue

 
Currently systematic reviews and guidelines state that Heliox should NOT be used in ALL patients with acute asthma  and that it doesn’t play a role in the initial treatment.
FORTUNATELY, those are not the patients that we would likely use Heliox in.  There are studies that point toward its benefit in selected patients with severe obstructive disease.

 
In IABPs:

Intra Aortic Balloon Pump (IABP) Counterpulsation utilizes helium gas to inflate its balloon. As Helium is a low density as well as an inert gas, in case of balloon rupture it is easily absorbed into the bloodstream. this may be heralded by high balloon inflation pressures.The key indicator of balloon rupture is the presence of blood in the connecting tubing.

 
Management involves
  • immediate cessation of counterpulsation
  • placement of the patient head down and IAB removal
  • Consider giving broad spectrum antibiotics as the gas chamber of the balloon is not sterile

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