Treatment of Infants and Children with Inhaled Helium/Oxygen

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FOCUS Fall
Bally’s Las Vegas
Oct. 1-3, 2013
Andy Brown RRT-NPS
Clinical Product Manager
Precision Medical Inc.
Northampton, PA

Yes, I do like the Pittsburgh Steelers!
 Sorry (I am from PA and lived in Pittsburgh)
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I work for Precision Medical Inc.
 We do manufacture and sell products for use with
Heliox
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I have been a Clinical Specialist with Bunnell
 Not really a heliox ventilator
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I have done research and published on the
topic of Heliox
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A) Sick Joke
B) Helium is dangerous
C) OOPS
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Janssen is credited with its discovery in 1868
Dr. Alvan Barach is considered to be the grandfather of
heliox therapy
Dr. Barach established the use of a low-density gas therapy
in 1934
He continued to present its use in asthma until 1976
“Remember to cure the patient as well as the disease”
Helium/Oxygen mixtures have been used in diving
applications since 1938
 Its first true test came in 1939 in the salvage of the
submarine “Squalus” at a depth of 240 ft. It has
been used since then for dives up to 2000 ft.
 Dr. Barach used a simple mouthpiece as well as tight
fitting masks to administer heliox
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Chemical symbol – He
Helium is the second lightest element in the
atmosphere with a molecular weight of 4.003
and an atomic number of 2
It is considered a rare gas with natural
concentrations of 5 ppm
Helium is chemically inert, nontoxic,
tasteless, and nonflammable
Helium has the lowest melting point of any element
Helium remains liquid down to absolute zero but
can be solidified by increasing the pressure
 Apart from hydrogen, helium is the most abundant
element
 The fusion of hydrogen into helium is the source of a
hydrogen bomb’s energy
 Helium exits the tissues faster than other gasses
decreasing the tendency to develop “the bends”
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Density
Viscosity
Laminar flow
Airway resistance
 Raw = ΔP/flow
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Diffusibility
 80/20 = 1.81
 70/30 = 1.59
▪ Varies inversely with the square root of density
Physics of Heliox
•
•
Helium is 2nd lightest element
When mixed with O2, reduces the density
Gas
Density(kg/m3)
Air
1.20
100% O2
1.33
Heliox 70/30
0.52
Heliox 80/20
0.40
Viscosity(µP)
183
204
199
198
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Density (symbol: ρ – Greek: rho) is a measure of mass per unit of volume.
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The higher an object's density, the higher its mass per volume. The average
density of an object equals its total mass divided by its total volume. A more
dense object such as lead will have less volume than an equal mass of some less
dense substance such as water. The SI unit of density is the kilograms/cubic
meter (kg/m3)
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r= m
V
where
 ρ is the object's density (measured in kilograms per cubic meters)
 m is the object's total mass (measured in kilograms)
 V is the object's total volume (measured in cubic meters)
The Logic of Balloon Boy’s Flight
Let’s have a MythBusters vote:
A) Plausible
B) Busted
C) Confirmed
Laminar vs. Turbulent Flow

Laminar Flow
– Flow characterized by
smooth, parallel layers of
fluid
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Turbulent Flow
– Flow characterized by
mixing of adjacent fluid
layers
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“Heliair” (80% helium and balance air)
 Rarely used in medical applications
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80/20 Heliox (80% helium and 20% oxygen)
70/30 Heliox (70% helium and 30% oxygen)
60/40 Heliox (60% helium and 40% oxygen)
THE CHOICE IS UP TO YOU!!!
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100%oxygen has a density of 1.429
40% oxygen has a density of 1.32
80/20 heliox mixture has a density of 0.43
(@1/3 100% and 40% oxygen)
70/30 heliox mixture has a density of 0.55
(@1/2 of 100% and 40%)
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80/20 heliox has a flowmeter conversion of
1.805
 10LPM of 80/20 flow on an oxygen flowmeter
equals a flow of 18LPM of 80/20
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70/30 heliox has a flowmeter conversion of
1.586
 10LPM of 70/30 flow on an oxygen flowmeter
equals a flow of 16LPM of 70/30
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Tank duration factors must also be taken into
account when heliox is being used
 80/20 heliox in a H cylinder has a factor equal to
2.50
 70/30 heliox in a H cylinder has a factor of
approximately of 2.70-2.80
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D(iameter)ISS/P(in)ISS/CGA considerations
 Available in “Egan’s Fundamentals of Respiratory
Care”
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While heliox has considerable potential to benefit patients in various settings, the
success of heliox therapy depends on the methods and devices used. Innovation
has been key to introducing heliox into clinical practice, but the practice of
modifying commercially available devices to function outside of their intended
design constraints creates considerable risk and liability for the patient, clinician,
and institution.
Only by understanding how helium affects devices and by becoming familiar with
how a device or system performs with heliox can researchers and clinicians safely
administer heliox. One of the best ways to minimize risk is to use devices that are
designed for heliox and cleared by the Food and Drug Administration (FDA) for
use with heliox, as they become available on the market.
100% Helium should never be used.
James Fink MSc RRT FAARC: June 2006 Respiratory Care
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There are no known contraindications for the use of Heliox
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Lung compliance issues (IHeAL Study)
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Establishments involved in the production and distribution of medical devices
intended for marketing or leasing (commercial distribution) in the United States
(U.S.) are required to register with the FDA. This process is known as
establishment registration. Registration provides FDA with the location of
medical device manufacturing facilities and importers. A registration fee is under
consideration by Congress.
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A 510k is a premarket submission made to FDA to demonstrate that the device to
be marketed is at least as safe and effective, that is, substantially equivalent, to a
legally marketed device
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A 510k requires demonstration of substantial equivalence to another legally U.S.
marketed device. Substantial equivalence means that the new device is at least
as safe and effective as the predicate.
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The holder of a 510k must have design control documentation available for FDA
review during a site inspection. In addition, any changes to the device
specifications or manufacturing processes must be made in accordance with the
Quality System regulation (21 CFR 820) and may be subject to a new 510k.
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Put simply, FDA prohibits companies from marketing medical
devices for uses that the federal agency has not approved. Offlabel promotion comes in two forms—marketing a device that has
not received FDA approval and promoting an approved device for
an unapproved use.
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Off-label promotion must not be confused with off-label use. The
FDCA expressly states that FDA is not permitted “to limit or
interfere with the authority of a healthcare practitioner to
prescribe or administer any legally marketed device to a patient
for any condition or disease within the legitimate health care
practitioner-patient relationship.” That means physicians are free
to use approved devices for unapproved uses—and, indeed, they
frequently do.
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Masks
 Simple
 Aerosol
 Non-rebreathing
▪ Most Common
▪ High Flow Systems
▪ Meets Patient’s Inspiratory Demand
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Nasal Cannula
 Conventional
 H3 NC
▪ Gaining popularity
▪ Flows that approach the patient’s inspiratory demand
▪ Evidence exists with pediatric patients and bronchiolitis
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Hoods and Tents
NEVER
 Helium’s Density
 Layering of gasses within the space
▪ (Helium balloons float right?)
Meyers adapted from:
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Blenders
 First free standing heliox blender introduced in
November 2009
 Blending of gasses in mechanical ventilation has
been available for a few years
▪
▪
▪
▪
Avea (CareFusion)
SERVO-I (Maquet)
G5 (Hamilton)
eVent Medical
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Monitors (Flow and Volume)
 Generally differential pressure pneumotachs
 Free standing monitors available
▪ NICO
 Incorporated into mechanical ventilators for
volume monitoring
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Nebulizers
 Controversy exists in the literature as to use heliox
as a carrying gas or to power the nebulizer with
the gas
▪ HOPE neb
▪ Aeroneb PRO
▪ Asthma Rescue Kit
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Ventilators
 Much research completed in the past as to
determine ventilator compatibility
 Approved devices
▪
▪
▪
▪
Avea
SERVO-i
Hamilton G5
GE Aptaer
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Heliox can generally be utilized with any
oxygen administration device
 Infants – nasal cannulas effective as well as masks
or ventilatory adjuncts (CPAP or conventional
mechanical ventilation)
▪ Oxyhoods
 Children and adults – high flow systems are
necessary
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Helium dilution for determining lung volumes
Upper airway obstruction
 Laryngotracheobronchitis (croup)
 Post-extubation stridor
 FBO
 Anatomical or structural anomalies
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Lower airway obstruction
 Asthma
 Bronchiolitis
 COPD
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Use in aerosol therapy
 Heliox powering nebulizer
 Heliox as a carrier gas
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Anoxia
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Measurement of Volume
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Amount of Medication
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Temperature
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Heliox Inhalation Therapy for Bronchiolitis in
Infants
 Cochrane Database Syst Rev. 2010 Apr 14;4:CD006915
 Randomized controlled trials (RCTs) and quasi-RCTs of heliox in infants with
acute bronchiolitis (84 infants under the age of 2 with respiratory distress with
bronchiolitis caused by RSV requiring PICU admission)
 AUTHORS' CONCLUSIONS: Current evidence suggests that the addition of
heliox therapy may significantly reduce a clinical score evaluating respiratory
distress in the first hour after starting treatment in infants with acute RSV
bronchiolitis. Nevertheless, there was no reduction in the rate of intubation, in
the need for mechanical ventilation, or in the length of PICU stay. Further
studies with homogeneous logistics in their heliox application are needed.
Such studies would provide necessary information as to the appropriate place
for heliox in the therapeutic schedule for severe bronchiolitis
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Vocal Cord Dysfunction
 Am Fam Physician. 2010 Jan 15;81(2):156-9
 Treatment of acute episodes includes
reassurance, breathing instruction, and use of a
helium and oxygen mixture (heliox). Long-term
management strategies include treatment for
symptom triggers and speech therapy
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Heliox for Croup in Children
 Cochrane Database Syst Rev. 2010 Feb 17;2:CD006822
 SELECTION CRITERIA: Randomized controlled trials (RCTs) and quasi-RCTs
comparing the effect of helium-oxygen mixtures with placebo or any active
treatment in children with croup.
 MAIN RESULTS: Two eligible RCTs were included (22 intervention, 22 controls).
Neither trial compared heliox inhalation with placebo. One study compared
heliox with 30% humidified oxygen whilst the other compared it to 100% oxygen
with additional racaemic epinephrine nebulization. There was no significant
difference in change of croup score between intervention and control groups.
 AUTHORS' CONCLUSIONS: At present there is a lack of evidence to establish
the effect of heliox inhalation in the treatment of croup in children. A
methodologically well-designed and adequately powered RCT is needed to
assess whether there is a role for heliox therapy in the management of
children with croup.
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Growth and Development in a Heliox
Incubator Environment: A Long-Term Safety
Study
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Neonatology. 2007;91(1):28-35. Epub 2006 Nov 10
DESIGN/METHODS: Four-day-old rabbit pups (n = 27) were randomized into control
(21% O(2); 79% N(2)) or heliox (21% O(2); 79% He) groups, then raised for 14 days at
26.7 degrees C and 50% relative humidity. Pups were euthanized on day 14, blood
drawn and primary organs, diaphragm and gastrocnemius weighed and snap-frozen.
Results: All pups thrived in both environments, achieving expected developmental
milestones. There were no physiologically significant group differences in weight,
growth factors, tissue weight, blood chemistry or muscle enzyme activity
 CONCLUSIONS: No observed long-term differences in growth or development. Results
demonstrated that long-term heliox exposure is safe in this rabbit model. These data
suggest that heliox administration may provide time for pulmonary improvement in the
BPD population, warranting appropriate clinical trials
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A search of PubMed on Heliox therapy yields
352 results
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Positive results for:
▪ COPD
▪ Asthma management
▪ Upper airway obstructions
▪ Nebulizing bronchodilators
▪ Pulmonary rehabilitation
 Negative results for:
▪ COPD
▪ Asthma management
▪ Croup
▪ Nebulizing bronchodilators
 Lack of large enough patient enrollment
 Poorly controlled studies
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Heliox for the treatment of bronchiolitis seems to have some of the strongest
evidence
Use of heliox as an adjunct or bridge to definitive therapy is successful
 Trauma
 VCD
 Acute episodes of Respiratory Distress
It is another form of therapy in a Respiratory Therapist’s armamentarium
 Common sense seems to lead to success
 If a patient is not responding to therapy do not delay increasing the intensity
of the therapy
 Heliox therapy has fickle results in the literature
▪ Properly designed studies and study populations
▪ What are the measureable goals of the therapy?
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Mortality
Intubation free days
Stay in the ICU
Decrease in WOB score
Inhaled Helium for the Treatment of Air Leak Syndromes
Presented at the Pediatric Academic Society Meeting 2006
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Retrospective Case Matched
Randomized to Nitrogen (4) or Helium (5)
Inclusion
 Evidence of PIE on CXR
▪ Mechanically Ventilated
▪ Unilateral or Bilateral
▪ SpO2
▪ OI
 Conclusion: Heliox therapy reduced PIE on CXR by
@40 hours
Literature is present on its use
Mainly small studies and anecdotal reports on its
use in small airway obstruction and nebulizer use
 Commonly used in treatment of large airway
obstruction
 Common sense and knowledge of potential benefits
and side effects is encouraged on its utilization
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