![Page 1: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/1.jpg)
MECHANICAL VENTILATION –
KEEP IT SIMPLES.Dial
Rounds 2020
![Page 2: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/2.jpg)
![Page 3: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/3.jpg)
![Page 4: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/4.jpg)
Ventilation
■ Brain
■ Nerves
■ Rib cage
■ Respiratory muscles
■ Ventilators can replace the
function of these parts of
the respiratory system
![Page 5: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/5.jpg)
The functional lung unit
![Page 6: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/6.jpg)
Gas exchangeMixed
venous
Inspired air
Arterial blood
Expired air
Alveolus
O2
CO2
Rate of exchange
determined by
metabolic rate
![Page 7: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/7.jpg)
![Page 8: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/8.jpg)
High flow nasal cannula
■ Humidification improves tolerance of high flows
■ Nasal cannula- better tolerated than full face mask – patients
can speak and eat
■ The high flows delivered results in less dilution by room air in
patients with high flows
■ Systems – Vapotherm, AIRVO, Ventilator, Optiflo
Critical Care 2016: 20:109 Roca et al
Respiratory Medicine 2009: 103, 1400 -1405
![Page 9: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/9.jpg)
AIRVO HFNC
A – 3
En
glish
AIRVO 2 AND ACCESSORIES
OXYGEN
INLET PORT
HEATER
PLATE FINGER
GUARD
AUTO-FILL W ATER
CHAMBER (MR290 )
(w ith adapt er fi t t ed)
Heated
b reat hing
t ube
Wat er chamber
Pat ient
int erface
Cleaning and Disinf ection
90 0 PT60 0 Disinfect ion Kit
90 0 PT60 1 Disinfect ion Filt er (2-Pack)
90 0 PT60 2 Cleaning Sponge-St ick (20 -Pack)
90 0 PT60 3 Clean Storage Cover (20 -Pack)
Miscellaneous
90 0 PT40 5 Pole mount ing t r ay
90 0 PT421 Hospital stand
90 0 PT422 Oxygen inlet extension kit
90 0 PT912 Filt er holder
90 0 PT913 Air fi lt er (2-Pack)
OPT0 12 W igglepads (OPT316/ OPT318)
(20 -pack)
OPT0 14 Oxygen Tubing (Opt iflow Junior)
Tube & chamber kits and pa tient interfaces
Tube & chamber kit Interfaces
90 0 PT531 Heated breathing tube,
MR290 aut o-fi ll chamber and
adapter (10 -Pack)
àOPT316 Nasal Cannula - Inf ant (20 -Pack)
OPT318 Nasal Cannula - Pediat ric (20 -Pack)
90 0 PT50 1
Heated breathing tube,
MR290 aut o-fi ll chamber and
adapter (10 -Pack)
à
OPT842 Nasal Cannula - Small (20 -Pack)
OPT844 Nasal Cannula - Medium (20 -P ack)
OPT846 Nasal Cannula - Lar ge (20 -Pack)
OPT870 Tracheostomy Direct Connect ion (20 -Pack)
RT0 13 Mask Int erface Adapter - 22mm (20 -Pack)
DISPLAY
AIRVO 2
HEATED BREATHING TUBE
CONNECTION PORT
CHAMBER PORTS
MEA SUREMENT POINT OF
DISPLAYED DEW POINT
TEMPERATURE
SERIAL PORT
AIR FILTER
FILTER COVERPOW ER CORD
and
CONNECTOR (PT10 1AZ/
PT10 1UK)
A – 3
En
glish
AIRVO 2 AND ACCESSORIES
OXYGEN
INLET PORT
HEATER
PLATE FINGER
GUARD
AUTO-FILL WATER
CHAMBER (MR290 )
(w ith adapt er fi t t ed)
Heated
breat hing
t ube
Water chamber
Pat ient
int erface
Cleaning and Disinf ection
90 0 PT60 0 Disinfect ion Kit
90 0 PT60 1 Disinfect ion Filt er (2-Pack)
90 0 PT60 2 Cleaning Sponge-St ick (20 -Pack)
90 0 PT60 3 Clean Storage Cover (20 -Pack)
Miscellaneous
90 0 PT40 5 Pole mount ing t r ay
90 0 PT421 Hospital stand
90 0 PT422 Oxygen inlet extension kit
90 0 PT912 Filt er holder
90 0 PT913 Air fi lt er (2-Pack)
OPT0 12 W igglepads ( OPT316/ OPT318)
(20 -pack)
OPT0 14 Oxygen Tubing (Opt iflow Junior)
Tube & chamber kits and pa tient interfaces
Tube & chamber kit Interfaces
90 0 PT531 Heated breathing tube,
MR290 aut o-fi ll chamber and
adapt er (10 -Pack)
àOPT316 Nasal Cannula - Inf ant (20 -Pack)
OPT318 Nasal Cannula - Pediat ric (20 -Pack)
90 0 PT50 1
Heated breathing tube,
MR290 aut o-fi ll chamber and
adapt er (10 -Pack)
à
OPT842 Nasal Cannula - Small (20 -P ack)
OPT844 Nasal Cannula - Medium (20 -P ack)
OPT846 Nasal Cannula - Lar ge (20 -Pack)
OPT870 Tracheostomy Direct Connect ion (20 -Pack)
RT0 13 Mask Interface Adapter - 22mm (20 -Pack)
DISPLAY
AIRVO 2
HEATED BREATHING TUBE
CONNECTION PORT
CHAMBER PORTS
MEA SUREMENT POINT OF
DISPLAYED DEW POINT
TEMPERATURE
SERIAL PORT
AIR FILTER
FILTER COVERPOW ER CORD
and
CONNECTOR (PT10 1AZ/
PT10 1UK)
![Page 10: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/10.jpg)
Physiologic mechanisms of action of HFNC
■ Washout of nasopharyngeal dead space – the expired air is
replaced by a fresh source of air with a lower pCO2 and higher
FIO2
■ Decreases the resistance of the upper airway on inspiration –
prevents potential narrowing related to negative intra-luminal
pressure
■ Warm humidified air improves conductance and pulmonary
compliance
■ Humidification of air through the nasopharynx uses energy –
therefore saves energy
![Page 11: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/11.jpg)
Physiologic mechanisms
■ Provides PEEP which is
dependent on the flow
■ Drying out of the mucosa
can cause damage which
interferes with muco-
ciliary clearance, this
increases the risk of
infections and atelectasis
– the humidification of
HFNC is thought to
decrease these risksMouth opening only decreases PEEP effect
on expiration
![Page 12: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/12.jpg)
Not as bad as you think, nebulizer –clean particles, not patient
![Page 13: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/13.jpg)
What they did in China
![Page 14: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/14.jpg)
Other ways to give high O2
■ You can add a filter to the
end of this
■ Filter
![Page 15: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/15.jpg)
CPAP
![Page 16: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/16.jpg)
What does CPAP do
■ Increase FRC
■ Bigger lung = bigger surface area for gas exchange
– Recruit partially collapsed alveoli
■ Improve compliance
![Page 17: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/17.jpg)
CPAP effect on compliance
![Page 18: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/18.jpg)
Ventilation
0 Brain
0 Nerves
0 Rib cage
0 Respiratory muscles
0 Ventilators can replace the function of these parts of the respiratory system
![Page 19: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/19.jpg)
Positive pressure
![Page 20: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/20.jpg)
![Page 21: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/21.jpg)
![Page 22: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/22.jpg)
Plateau pressure measurements
![Page 23: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/23.jpg)
Plateau pressure
![Page 24: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/24.jpg)
Positive pressure and PEEP
0 PEEP
PEEP
= 10
![Page 25: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/25.jpg)
What do you order
■ RR - Respiratory rate = 12 – 24
■ Vt or Tidal volume = 4 – 8 ml /kg
■ PEEP – 5 – 24 ? Average on COVID = 10
■ This is a recipe that has been used to which I have some
reservations – treatment arm outcome was no different than
controls
![Page 26: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/26.jpg)
VILI
■ Volutrauma or baro – likely combination of both
– Physiology – think of upper and lower inflexion points
![Page 27: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/27.jpg)
Some terminology
■ How does the ventilator when the patient is inspiring = trigger
■ Tidal volume ?= you tell it how much to give or you provide a pressure and the Vt can vary (Pressure support of pressure control)
■ How fast is the tidal volume delivered = flow
■ How does machine know when to stop delivering the breath = cycle
![Page 28: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/28.jpg)
![Page 29: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/29.jpg)
![Page 30: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/30.jpg)
![Page 31: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/31.jpg)
Hypercarbia
Clinically elevations in the pCO2 are more likely to
be a consequence of decreases in the alveolar
ventilation than increased production
Alveolar ventilation (VA ) = Total minute ventilation
– dead space ventilation
Dead space = non perfused alveoli – larger airways
VE = frequency of respiration(breaths/minute) x
tidal volume (Vt).
Decreases in alveolar ventilation can occur either
from a decrease in the total minute ventilation or
an increase in the dead space ventilation or both.
![Page 32: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/32.jpg)
Alveolar ventilation
■ VA = f (Vt - Vd)
■ Effect of breathing pattern
– 12 x (600-150) = 5400ml/min
– 24 x (300 – 150) = 4200ml/min
■ Effect of machine added dead space
– 12 x (600 – (150anat + 100apparatus )) = 4200
ml/min
![Page 33: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/33.jpg)
Relation between minute ventilation and pCO2
pCO2
Alveolar
ventilation
At higher pCO2 values, smaller changes in alveolar
ventilation result in large increases in pCO2
![Page 34: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/34.jpg)
Prone positioning
![Page 35: Modes of Mechanical Ventilation - McGill University€¦ · MECHANICAL VENTILATION – KEEP IT SIMPLE S.Dial Rounds 2020. Ventilation Brain Nerves Rib cage Respiratory muscles Ventilators](https://reader033.vdocuments.site/reader033/viewer/2022060523/6052fbcfb25b8e7fe0571905/html5/thumbnails/35.jpg)
Proning – PROSEVA trial -ARDS
■ You turn the patient on
their stomach and leave
them for 12-16 hours of
the day
■ There are videos on how
to do it – NEJM
■ https://www.nejm.org/do
i/full/10.1056/NEJMoa1
214103