High Flow Therapy (HFT)
in the Adult Population
Agenda
•
High Flow Mechanisms of Action
•
Clinical Application and Research
•
Precision Flow® Demonstration
•
Q&A
High Flow Therapy: Definitions
- Flow rate that exceeds patient flow demands at various minute volumes
● A method to achieve actual FiO2 of 1
● Eliminate entrainment of ambient air
- Accomplished in the nasopharynx only with proper gas conditioning
● Conventional cannula therapy limited by nasal damage
● HFT becomes more than oxygen therapy
- Combination of technologies to achieve optimal
temperature, humidity and flow rate
at the point of delivery
HFT Clinical Review
Flow First™
4
Continuum of Care: Old Model
Weaning
Rescue
Acuity
Mechanical
Ventilation
Bi-Level
CPAP
Bi-Level
CPAP
General 02
Therapy
General 02
Therapy
Choice of Therapy
5
Continuum of Care: New Model
Weaning
Rescue
Mechanical
Ventilation
Acuity
Bi-Level
CPAP
Bi-Level
CPAP
High Flow
Therapy
General 02
Therapy
General 02
Therapy
Choice of Therapy
6
Control the Factors that Matter…
Combination of
proprietary technology to
achieve optimal:
 Flow
 Fi02
 Temperature
 Humidity
at the point of delivery.
High Flow Therapy: Mechanisms of Action
Flush Dead Space
● CO2 Elimination
● Oxygen Efficiency
Supports Inspiration
● Cannula Flow > inspiratory
● Work of Breathing
Humidify / Warm Airways
● Mobilization of Secretions
● Nasal comfort
8
Humidify / Warm Airways
Inspiratory Gas Conditioning
●Nasopharynx is highly
efficient at conditioning
inspiratory gas
●Anatomical Structure
●Mucosal Architecture
Humidify / Warm Airways
Humidify / Warm Airways
Conditioning Prevents Injury
Inadequate warming and humidification can cause:
●
Thickened Secretions
●
Decreased mucocilliary action
●
Thermal challenge
●
Bloody secretions
●
Lung atelectasis
Inspiratory Gas Conditioning
Why BTPS?
●Williams et al, 1996, Crit Care Med 24(11):
1920-9
Flush Dead Space & Support Inspiration
Pulmonary Physiology
Oxygenation
PiO2 ~150 mmHg
Ventilation
Ambient Air
PiCO2 ~0 mmHg
PAO2 ~100 mmHg
Alveolar
PACO2 ~40 mmHg
PaO2 ~95 mmHg
Blood
PaCO2 ~40 mmHg
Pulmonary Physiology and Dead Space
Pulmonary Physiology and Dead Space
Pulmonary Pathophysiology
Pulmonary Pathophysiology
Flush Dead Space & Support Inspiration
● High nasal flow, unimpeded at
mouth, fills the upper airways –
storing O2 during exhalation and
flushing CO2
● High mask flow, impeded by
pressure at the mouth - stores less
O2 in the upper airways during
exhalation and adds prosthetic
dead space
Tiep, et al: Resp Care, 2002: High Flow Nasal vs High Flow Mask oxygen delivery: Tracheal Gas
Concentrations Through an airway model
Mechanism of Action Review
Dead space washout
● Supports CO2 ventilation
● Enhances oxygenation
Matched inspiratory flow
● Attenuates nasopharyngeal resistance
Adequate gas conditioning
● Improves conductance and compliance
● Reduces energy cost of gas conditioning
Mechanisms by Application
HFT DOES NOT TREAT A DISEASE, THE MECHANISMS TREAT SYMPTOMS
Oxygen
Flush
Humidity
Mild
Pressure
COPD
Fibrosis
Asthma
CHF
Here are merely a few disease states and how the mechanisms of
action treat the symptoms.
Can you think of other respiratory insufficiencies where the
symptoms can be treated by HFT?
21
The Interface…Delivering the Flow
Platform “A”
22
Platform “B”
Calculating Minimal Flow
AARC Definition….
……flows that exceed patient demand at various minute
volumes.
Textbook Adult Values:
Tidal volume = 500ml
Breathing rate = 12 / min
Inspiratory fraction = 0.3
Spontaneous Inspiratory Flow avg. = 20 lpm
+ what is the peak flow?
+ Are they larger?
+ Are they breathing heavy?
Err Aggressively…but within reason
Calculating Minimal Flow
Extrapolated from equations in Mosby’s Respiratory Care Equipment, 7th Ed.
Flow Requirements: Adults
Inhalation:
RR = 12+
Tidal Volume = 500ml
Inspiratory time fraction = 0.3 (~1.5 sec)
= 25 - 35 LPM
Exhalation:
Expiratory time = ~3.5 sec
Extrathoracic dead space = 0.8 ml/kg (~50 ml)
Inhalation flow is sufficient
25
Indications for Use:
Indications:
●
Spontaneously breathing patients who are requiring supplemental
oxygen therapy
●
Any patient who is on an oxygen mask that is: 1. Not compliant, 2.
not improving, 3. Or has an increase in work of breathing
●
Post- extubation support or weaning from NPPV
●
Patients requiring supplemental heat & humidity for artificial airways
Contraindications:
● Patients not spontaneously breathing
● Patients that have a deviated septum
● Patients with severe facial trauma or disfigurement
Clinical References
● Calvano et al. - Respir Care 2008; 53(12):1739-43.
- HFT stabilizes end-stage respiratory failure patient on HFT just to make her comfortable
when she refused intubation and biPAP.
● Dewan & Bell. - Chest 1994;105:1061-5
- Oxygenation improved but also work tolerance and reduced dyspnea with high flow cannula
● Hasani et al. - Chron Respir Dis 2008: 5, 81-6
- Showed that mucocilliary functions are actually improved with BTPS humidification
● Chatila et al. - Chest 2004;126:1108-15
- Temple Lung Center in Philadelphia showed in COPDers that with Vapotherm blood O2 and
CO2 improves as did work performance.
● Dysart et al. - Respir Med 2009;103:1400-5
- Summarizations of the Mechanisms of Action of HFT
Precision Flow® Overview
• Flow, FiO2, Temperature All In One
• One Control, Easy To Use
• Smart Technology
• Robust Design w/ Limited Maintenance
• Audio/Visual Alarm Functionality
• Quick Start Up
• No Disinfecting
Precision Flow™ Integrates Humidification and Gas
Blending in One Device
Main Unit - Front Panel
Flow Display
Oxygen
Display
Temperature
Display
Alarm Mute and
Display Dim
Run, Standby
Button
Setting Control Knob
Safety Features
Battery Low, Charging
Blocked Tube Alarm
Disposable Water Path
Fault or Absent
Cartridge Fault
Water Out Alarm
System Fault Alarm
High and Low
Cartridge Indicators
Gas Supply Fault
Disposable Patient Circuit (DPC)
The Disposable Patient Circuit
(DPC) Consists of
Water
Spike
Filter Membrane
Three Components:
1. Disposable Water Path (DWP)
2. Vapor Transfer Cartridge (VTC)
3. Patient Delivery Tube
Cartridge
Sensors
 30 Day on Single Patient
 Available Low or High Flow Kits
Impeller
Heater
Plate
Delivery
Tube
Precision Flow Overview:
Vapor Transfer Cartridge:
● Key to efficient, high performance
humidification and gas conditioning
● Also serves as filter--pore size
much smaller than 0.05 microns
Patient Delivery Tube:
● Patented triple lumen design
● Design prevents rain-out
● Keeps gas conditioned out to
patient
● Safer than traditional heater wire
design
Q&A