focus spring conference - presentation - lecture - the science of hmes - may 2014
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TRANSCRIPT
The Science of HMEs
1 May 2014
The Artificial Nose:•How does it function•The 6 types of passive humidifiers•Design•The 3 Cs•Moisture media•Important features•Documentation of effectiveness•What to look for when choosing a passive humidifier.
3 May 2014
Ancient man discovered medicinal plants by observation and experience.
Inhaling smoke from plants was common to get pleasure and relief from body troubles.
Nearly all respiratory troubles were treated by one form or another of inhalation.
4 May 2014
Inhalation Therapy
5
Treatment for Respiratory Ailments Were Common During the Late 1800s
February 2012
Compound Oxygen“Scientific adjustment to oxygen and nitrogen”
Drs. Starkey and Palen, 1888
6 May 2014
7 May 2014
8
Compound oxygen was not oxygen at all, but a very dilute "laughing gas” made by heating ammonium nitrate.
The inhaled gas was mixed with ferric carbonate or potassium chlorate, to give it color and help assure patients they were inhaling something tangible and useful.
May 2014
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Indications for Compound Oxygen• Asthma• Bronchitis• Indigestion• Hay fever• Headache• Rheumatism• Neuralgia• Diarrhea …and cured none
May 2014
10 May 2014
The American Association of
Inhalation Therapy
The University of Chicago Hospital establishes the
Inhalation Therapy Association
in 1946
11 May 2014
The American Association of Inhalation Therapy was the first to issue certification classes for Inhalation Therapists.
It was an on-the-job training system for so-called "oxygen jockeys.”
12 May 2014
An Early Oxygen Tank
13 May 2014
• “Humidification of inspired gas during mechanical ventilation is mandatory when an endotracheal or tracheostomy tube is present.• This may be accomplished using either a heated humidifier or a heat and moisture exchanger.• The chosen device should provide a minimum of 30 mg H2O/L of delivered gas at 30° C”.
Respiratory Care (Respir Care 1992;37:887-890)AARC Clinical Practice Guideline
Humidification during Mechanical Ventilation
14 May 2014
15
What is
30/30?
February 2012
16
30/30
February 2012
17
Active? Passive? Both?
It is very important for respiratory therapists to evaluate each patient individually and choose the correct device.
May 2014
Clinical Practice GuidelinesDuring Mechanical Ventilation
The Clinical Practice Guidelines imply that unless specifically contraindicated, the HME will be acceptable.
Clinical Foundations, A Patient-focused education program for Respiratory Care Professionals, Humidification During Mechanical Ventilation:
Current Trends and ControversiesTim Op’t Holt, EdD, R.R.T., AE-C, FAARC
18 May 2014
“HMEs should be used in all patients in whom there is no contraindication.”
Richard D. Branson MSc RRT FAARC
19
June 2005Respiratory Care Journal
November 2011
Advantages of Using Active HumidifiersDuring Mechanical Ventilation
•Have alarms• Are capable of regulating and monitoring temperature•Work with all patients, universal• Seem to be reliable•Heated wire helps to reduce condensate.
20 May 2014
Advantages of Using Active HumidifiersDuring Mechanical Ventilation
•Offers wide variation of options in treating patients, versatility• Preferred method of humidification with pre-existing conditions such as COPD.
21 May 2014
Disadvantages of Using Active Humidifiers During Mechanical Ventilation
• Temperature setting is not humidity delivered• Costly, possibilities of malfunction and down time•Use problems as reported in MAUDE – Manufacture and User Facility Device Experience
22 May 2014
Disadvantages of Using Active Humidifiers During Mechanical Ventilation
•May develop condensation within the circuit• Possible infectious waste (biological hazard) drainage into heater reservoir, the ventilator and more• Complex to use with over or under hydration possible•May not produce as much humidity as thought.
23 May 2014
Biological Hazards
• Biological hazards refer to biological substances that pose a threat to the health of living organisms, primarily that of humans.
• The term and associated symbol are generally used as a warning, so that those potentially exposed to the substance will know to take precautions.
From Wikipedia, the free encyclopedia
24 May 2014
Secretions = Biological Hazard
25 May 2014
Heated Humidifiers
26
Puritan-Bennett
Cascade Humidifier
May 2014
The Artificial Nose
May 201427
28 May 2014
What is an Artificial Nose?
• Commonly called a HME and or filter (although filter media may not be present)
• These humidification devices function without the addition of a water source or electricity
• These devices collect and conserve the patient’s expired moisture and heat.
29
November 2011
The Artificial Nose
The first heat and moisture exchanger, which was made with corrugated aluminum, was presented by a group of Swedish professors in the early 1960’s.
Due to its weight, the device never became widely used.
30
November 2011
The Artificial Nose
The aluminum was replaced with a special paper in a corrugated structure with a large capacity for absorbing and giving off moisture.
Over the years the “noses” have been gradually developed and the design has been refined.
The market breakthrough for the artificial nose did not occur until the beginning of the 1970’s.
31
November 2011
32 May 2014
Humidification During Mechanical Ventilation
Indications:• Humidification of inspired gas during mechanical
ventilation is mandatory when an endotracheal or tracheostomy tube is present. • When providing passive humidification to patients
undergoing invasive mechanical ventilation, the HME should provide a minimum of 30mg H2O/L.
RESPIRATORY CARE • MAY 2012 VOL 57 NO 5
33 May 2014
Humidification During Mechanical Ventilation
HME Contraindications:• Use of an HME may be contraindicated for patients with high spontaneous minute volumes > 10L/min.• There are products on the market which deliver
30mg of moisture at 20 liter minute volumes.
34 May 2014
Humidification During Mechanical Ventilation
HME Contraindications:• An HME must be removed from the patient circuit during aerosol treatments when the nebulizer is placed in the patient circuit.• With some products, placing a nebulizer between the PH
and patient may not create a problem.• Pressures should always be monitored during any
treatment.
35 May 2014
Humidification During Mechanical Ventilation
HME Contraindications:• Use of an HME is contraindicated for patients with body temperatures less than 32° C . • These hypothermic patients may be better managed using a heated humidifier because it may be more efficient at reducing further heat loss.
36 May 2014
Humidification During Mechanical Ventilation
HME Contraindications:• Patients with pre-existing pulmonary disease characterized by thick, copious, or bloody secretions should not use PH.
• Use of an PH is contraindicated for patients with an expired tidal volume less than 70% of the delivered tidal volume - those with fistulas or absent endotracheal tube cuff.
37 May 2014
Advantages of Using Passive HumidifiersDuring Mechanical Ventilation
• Simple to use, no moving parts• Produce dry, cool circuits which lowers the risk of contamination•No need for water or electricity•No down time• Lightweight, portable, easy to use and store
38 May 2014
Advantages of Using Passive HumidifiersDuring Mechanical Ventilation
• Impossible to over hydrate the patient• Impossible to over heat or burn the patient•Helps to eliminate condensate in tubing • Lower humidification costs • Faster and dry circuit changes - eliminates the possible exposure to condensate which is considered infectious waste
39 May 2014
Disadvantages of Using Passive Humidifiers During Mechanical Ventilation
•May increase airway resistance• Increased dead space may create excessive rebreathing – especially with small tidal volumes • Potential for occlusion•Not suitable for all patients.
40 May 2014
Disadvantages of Using Passive Humidifiers During Mechanical Ventilation
• Possible pneumothorax• Increase in weight over time – ET tube associated problems • The maximum amount of water vapor which can be delivered to the patient in a specific volume of gas will vary with different temperatures
41 May 2014
Disadvantages of Using Passive Humidifiers During Mechanical Ventilation
Again, The maximum amount of water vapor-
which can be delivered to the patient in a specific volume of gas-
will vary with different temperatures and different devices
42 May 2014
Advantages of Using Active HME HumidifiersDuring Mechanical Ventilation
• Universal application• Helps to eliminate condensate in tubing • Helps to produce dry, cool circuits with lower water
consumption• Has alarms• Continues passive humidifying if electricity or water
fails
43 May 2014
Disadvantages of Using Active HME HumidifiersDuring Mechanical Ventilation
• Extra dead space• Potential for occlusions, high pressure, etc.• Limited temperature variations to choose• Heater close to patient• Must be removed to deliver aerosols• Cost savings only when compared to active
systems, not HMEs
44 May 2014
All “Noses” Are Not Alike!
45 May 2014
6 Types of Passive Humidifiers
46 May 2014
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• heat and moisture exchanger
HME
• filter heat and moisture exchanger
FHME
May 2014
48
• hygroscopic condensing humidifier
HCH
• filter hygroscopic condensing humidifier
FHCH
May 2014
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• gas flow may be redirected to and around the media
Bypass HME
• heat and water added to the HME
Acti ve HME
May 2014
50 May 2014
Hygroscopic:
The ability of a substance to attract and hold water molecules from the surrounding environment by enhancing the natural physical properties.
This is achieved through either absorption or adsorption with the absorbing or adsorbing material becoming physically "changed.”
51 May 2014
Absorption: Incorporation of moisture. This moisturebecomes a part of the media
Adsorption: Adhesion of moisture to a surface
Adsorption is a surface-based process while absorption involves the whole volume of the material
Coffee Pour Test
52
Looking for:• Media absorbing• Media non-absorbing
Pour coffee (so you can see) into the PH media to see if the media absorbs the coffee.
Absorption of coffee represents the media taking moisture from the patient’s breath and becoming part of the product.
Only a small portion of this moisture will be delivered back to the patient.
May 2014
Coffee Pour Test
53 May 2014
Examples of Passive and Active HMEs
54 May 2014
Examples of Passive Humidifier Designs
55 May 2014
Examples of Passive Humidifier Designs
56 May 2014
Many flex tubes will add about 2 mg of moisture
Examples of Trach Passive Humidifier Designs
57 May 2014
Many HME Products Fail to Meet the Patient’s Needs Resulting in Adverse Events
• High pressure alarms• Spontaneous pneumothorax• Thickening secretions• Endotracheal tube occlusions• Plugged airways• And more…
58 May 2014
Examples of Humidification Media
59 May 2014
Clinicians Should Remember-Actual Moisture Output Varies
• As gas volumes increase moisture output decreases
• When gas moves through the media quickly, the ability
of the device to remove moisture from exhaled gas and add moisture to inspired gas- diminishes• Most do not begin humidifying until some time later,
maybe a hour or two.
60 May 2014
Replaced HME q 24 hours
Bloody secretions? Thick tenacious sputum?
Less than 70%? Core temp less 320 C?
Evaluate secretion quality and quantity
Examine patient
Use heated humidification
Examine patient’sHx/Px
More than 4 HMEs used in 24 hours?
NO
YES
YES
NO
May 201461
Humidification for Patients with Artificial Airways RESPIRATORY CARE; JUNE 1999; VOLUME: 44 NO 6; page 638
Patient’s humidity level drops over time
RRT replaces HME and perceives everything to be ok
Patient’s humidity level drops over time
Don’t be Fooled, The 3Cs
① Charging② Coring③ Collecting
64 May 2014
Don’t be Fooled, The 3Cs
① Charging
65 May 2014
“Charging” Function of Media
• “The longer you use the hme, the better it works” is a common misunderstanding• In reality, the longer these devices are used, the
more moisture is absorbed from the patient’s breath• The patient may have less moisture after using
these devices because moisture is absorbed into the media.
66 May 2014
“Charging” Function of Media
67 May 2014
Don’t be Fooled, The 3Cs
② Coring
68 May 2014
“Coring” Possible Result of Design?
•Many products are constructed with diffusors, walls, wings, etc. to help move the gas flow around inside the housing• Rebreathing occurs in the center of the media
• Causing increased pressures• Possible absorption of humidity from the patient’s
breath
69 May 2014
“Coring” Possible Result of Design?
70 May 2014
Don’t be Fooled, The 3Cs
③ Collecting
71 May 2014
Collecting…
72
gas in
May 2014
gas in
gas out
Collecting…
73 May 2014
The 3Cs
① Charging② Coring③ Collecting
74 May 2014
Most Important Features of PH
75
Filter?
Cost?
Resistance?
Moisture output?
Dead space?
Design?
Respiratory Care; June 1999; Vol. 44 No. 6; Pg. 636
May 2014
Trend of Humidity Delivered
HME lowest
HMEF HCH HCHF highest
76 May 2014
Respiratory Care; June 1999; Vol. 44 No. 6; Pg. 636
Should PH be Chosen BasedUpon Minute Ventilations?
5L VE
10L VE
15L VE
20L VE
77 May 2014
Humidifiers should deliver 30/30 for all minute volumes
Is My Patient Being Humidified?
Regardless of what type of system is being used, the clinician should
question the effectiveness.
Since no system reports the actual amount of humidity being delivered, other signs must be relied upon.
78 May 2014
Observe inside the circuit elbow, circuit wye and HME housing for condensation
79 May 2014
Bedside hygrometers will give feedback however - only a moment in time
80 May 2014
Sputum Descriptions
• What is a Spudic?• It takes 6 Spudics to make one Sputum• It takes 10 Sputums to make on Spudi• It takes 10 Spudi to make on honker!
81 May 2014
Assessment of Sputum Characteristics
Suzukawa’s Method:Thin Suction catheter is clear of secretions following‐suctioning
Moderate After suctioning, the suction catheter has ‐secretions adhering to the sides that are easily removed by aspirating water
Thick After suctioning, the suction catheter has ‐secretions adhering to the sides that are not removed by aspirating water
82 May 2014
Research Independent Documentationof Effectiveness
• Third party documentation • Does the investigator have a financial interest?• Are the studies clinical or non-clinical settings?
Many believe in house studies are like baseball catchers calling their balls and strikes!
83 May 2014
84
This patient was featured on The Learning Channel.
2nd and 3rd degree burns over 60% of the bodyand 3 months LOS (tracheal not comprised)
Only this product was used to humidify the patient.Used with permission
May 2014
MHRA & UK Medicines Healthcare Products
85 May 2014
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Richard Branson’s evaluation of 21 HMEs, Table 2. (Respir Care 1996; 41:736-743)
May 2014
Documentation of PH Effectiveness
FDA – MAUDE Database
Manufacturer and User Facility
Device Experience
87 May 2014
MAUDE Adverse Event Report
The attending staff removed the patient from the mechanical ventilator and began manual ventilation. The patient was resuscitated successfully.
The circuit was examined and the HME device was determined to be blocked.
The device was removed and replaced with a new device. Mechanical ventilation was resumed.
88 May 2014
Early Coffee Cups
89 May 2014
Too Late to Check Effectiveness
90 May 2014
What to Look For When Choosing a PH
91
???
May 2014
What to Look For When Choosing a PH• Will the PH deliver the 30/30 guidelines for all patients - for 24 hours at all minute volumes?
• Does the moisture output data include minute volumes?
• What is the weight and resistance at the end of 24 hours of use, not after a few hours?
92 May 2014
What to Look For When Choosing a PH• What is the dead space?• What is the tidal volume range?• Is the PH designed for ICU use or a cross-over product being ordered for both anesthesia and respiratory use?• Is a circular housing used to help prevent possible bruising?
93 May 2014
What to Look For When Choosing a PH• Is hydrophobic humidification media incorporated to prevent absorption?• Is a “change on date” label needed?•Does it begin humidifying after the first breath?• Will there be an increase in weight due to the absorption of moisture?
94 May 2014
What to Look For When Choosing a PH• Is the housing clear so secretions and condensation can be observed?• The PH selected should be appropriate to the patient's dead space and tidal volume.• Is a filter needed?• If it is a filter product, does it have non-absorbing filter media?
95 May 2014
“Our findings suggest that the initial application of an extended-use hygroscopic condenser humidifier is a safe and more cost-effective method of providing
humidification to patients requiring mechanical ventilation compared with heated-water
humidification.”
Chest. 1998 Mar; 113(3): 759-67.A randomized clinical trial comparing an extended-use hygroscopic condenser humidifier
with heated-water humidification in mechanically ventilated patients.Kollef MH, Shapiro SD, Boyd V, Silver P, Von Harz B, Trovillion E, Prentice D.
96 May 2014
Questions?
May 201497