HIGH FLOW NASAL CANNULA (HFNC)

- Variation of the standard nasal cannula

o Designed to provide warmed and humidified oxygen
o Totelrated by severely hypoxemic patient than HME Provides 100% relative humidity
- FiO2 is constant and generally lower than expected. NIV interfaces increase anatomical dead
space, HFNC decreases dead space
o Because HFNC is just a nasal prong
o NIV is a mask

IMPORTANT POINTS

- To ensure adequate flow rates on devices set on 60% or higher, use two flowmeters connected
together
- Kinked aerosol tubing or water in the tubing causes back pressure into the nebulizer decreasing
the amount of air entrained and therefore increasing the percentage of O2
- Increasing the flow on a high-flow device does not increase the delivered Fio2, it only increases
the total flow

INDICATIONS

- Hypoxemic respiratory failure = Type I

- Hypercapnic respiratory failure = Type II
- Reduce reintubation risk
- Do not intubate or Hospice patient
- Inability to tolerate other devices

CONTRAINDICATIONS

- Blocked nasal passages

- Inability to precisely determine and monitor the level of positive pressure
o Disadvantage of HFNC; cannot determine the exact pressure given
- Nasal skin erosion (mainly neonates and infants)
- Epistaxis
- Basilar skull fracture
- Gastric distention
- Excessive PEEP (Positive End Expiratory Pressure) in newborns -> leads to pneumothorax
o Too small PEEP -> atelectasis
o Too big PEEP -> pneumothorax
 Units = cm H2O
- Delayed intubation hoping HFNC will correct complications
COMPONENTS

ALL HFNC

- Patient interface such as nasal prongs

- Gas delivery device that regulates FiO2
- Humidifier

Ability to maintain a consistent FIO@ under varying breathing patterns makes these devices suitable
alternatives for early intervention in critically ill patients, as well as the preincubations and
postintubation phase of care

- To hyperpoxygenation
- To opening of alveoli in post extubation

These systems have been shown to successfully treat moderate hypoxemia through a combination of the
four main features:

1. Delivery of High FIO2

2. Fixed oxygen delivery device
3. Generating PEEP of approx. 1cm H2O each 10LPM
4. Washout of CO2 from anatomic dead space

Highly humidified oxygen, thus preventing the drying effects

HFNC substitute for high flow devices and CPAP

FLOW METER

- Flow more common in infants

o Infants 10LPM
o Adult: 40 LPM
- Sterile water
o To bring the heating
- Humidifier (Wick humidifier)
o Gas should always be conditioned: Approx. 5 to 10 minutes
 Before it is connected to the patient
 Sterile water
 Automatic lock and manual lock
 Hot-plate
 Arrow level should be the sterile water
 Not above
 Not too little
 - LACKING OF HUMIDIFICATION ADVERSE EFFECT
o Decreased nasal and respiratory cilia

NASAL PROGNS

- To prevent inadvertent high levels of CPAP from developing,

o NASAL PRONGS SHOULD NOT OCCUPY MORE THAN 50% FROM THE PATIENT NARES

HEATED TUBES

INTERFACE
FLOW up to 60LPM
Temp heated to 37 degrees
- Set the flowmeter itself to set the device (interface)
- Change the High-flow @ the monitor if the order is to set the flow
- Change flow at the interface
- Change O2 at the Flowmeter

BUBBLE CPAP
- BUBBLE Continues Positive Airway Pressure
- Humidification
- Provides continuous pressure that helps prevent de-recruitment of alveoli, increasing the lungs’
FRC, and thus decreasing the WOB
- Application of positive pressure to the airway only for spontaneously breathing patient
o Throughout the respiratory cycle
- Nasal CPAP is commonly used in the NICU
- Can be a mode in mechanical ventilation
- Can be a way of weaning
- Maintains inspiratory and expiratory pressure, icreases in FRC and improvement in static lung
compliance, and decreseasd in airway resistance
- CPAP stens open the airways
- Expiratory limb of the system in submerged in a sterile water chamber
o Bubbling provides a unique oscillation via the submersion in sterile water
o Of the expiratory liumb of the system
- Oscillation are an important feature that distinguish bubble CPAP from other forms of CPAP
 o Initial pressure are commonly set at about 4 to 6 cmH2O (neonatal)
o Results in adequate lung inflation without over distending the lung parecnchyma
o Maximum of 10cmH2O (increments of 1 to 2 cmH2O)
 Every two hours until reached
o Response is considere adequate when required FiO2 is 60% or less and the PaO2 is at
least 50mmHg
o Adequate oxygenation is usually accompanied by reduced WOB as manifested by a 30%
reduction in respiratory rate and a decrese in
- Oxygen flow rate 5-10LPM, adjusted until gaseous bubbling is see n
o The higher the flow the higher the pressure the more bubble
- The gas flowrate is an important varible
o Bubble CPAP has been shown to
 Reduce alveolar structural damage
 Reduce pulmonary edema
o Overtime, bubble CPAP resultsin
 Higher fluctuation of pressure
INDICATIONS
- Respiratory distress
- Inadequate ABG values
o PAO2 >50mmhg with FiO2 of <60%
- Presence of the ff conditions
o RDS
o AOP
o PE
o Recent extubation
o Atelectasis
o Transient tachypnea of newborn
- Early intervention in conjuction with surfactant administration for very low birth weigh infants at
risk for developing RDS
- The administration of controlled concentration of nitric oxide in spontaneously breathing infants
CONTRAINDICATION
- Upper airway abnormalities that make NCAP ineffective or potentially dangerous
- Severe cardiovascular problem
CPAP works on the continuous flow princpiples
CPAP uses blended air and oxygen that is headted and humidified then delivered via low resistance via
nasal mask and prongs
Bubbling and pressure will cease if blocked displaced
Frequent intermittent checks are mandatory
Bubble CPAP pressure
Baby are mouth breathers naturally
- Hence when babies cry then can become cyanotic

Bubble CPAP
- May prevent the need for intubation when used immediately at birth, in late preterm and term
infants, and when used continuously in preterm infants; Until 32 weeks AOG
- Used continuously in preterm infants
- May be ineffective if the neonate wiehg less than 1000-1200g

MONITORING
- System check should be perfomed at least every 2 to 4 hours and included documentation of
setting and patient assessment
- Oxygen and carbon dioxide monitoeing including
o Periodic sampling of blood gas values (arterial,capillary, or venous route)
o Contionous monitory of ECG
SET-UP
HYPERBARIC O2 THERAPY
- Therapeutic use of O2 at pressure greater than 1atm
- Entierly enclosed, patient breathes 100% oxygen at a pressure >ata
o 760mmHg
o Affection of the lung
Administration of 100% O2 to the patient placed in enclosed chamber pressured at >1 atm
o O2 dissolved in arterial blood plasma is increased thus this dissolved plasma O2 is
carried out to different tissue
PRIMARY MOA
- Hyperoxygenation
o Applpication of Henry’s law
- A pressure of 3 ATA results in 6mL of O2 being dissolved per 100mL of plasma
o Management of crush injury, compartment syndrome, flap salvage, and acute blood loss
anemia
- Decrease in Bubble size
o Boyle’s law
o Volume of a bubble decreases diretly in proportion to increase pressure
- Vasoconstriction
o Reduces post traumatic tissue edema
- Angiogenesis
o Hypoxia is a vital stimulat for angiogenesis
 Increases the oxygen gradient
 Increased neovascularization

- Mostly used 2.4 atm

o 4 atm induces seizures