ASSISTED VENTILATION
-
Upload
emberlynn-aerts -
Category
Documents
-
view
33 -
download
0
description
Transcript of ASSISTED VENTILATION
ASSISTED VENTILATION
By:
Dr.SaifAssistant Professor Of Paediatrics
Allied Hospital Faisalabad.
Definition
“Movement of gas into and out of lungs by an external source connected to the patient”
History
Hipocrates (400 B.C) work ignored for next 1000 years.
Paracealsus (1493-1541) Bellow and oral tube.
Vide Chaussier and his successors (1879). Aerophore pulmonare.
Fell-O’Dwyer apparatus (1887)
Alexander Graham Bell’s Negative Pressure Ventilator(1889)
Five Ws of assisted ventilation
WHOWHEN WHATWHEREWHY
Types of ventilators
Negative pressure ventilators
e.g, Airshield “Isolette respirator”
• Advantages:
o Less oxygen toxicityo Less pulmonary infectiono Less chances of atelectasiso Less pulmonary air leakso Less airway trauma
• Disadvantages: o Patient inaccessible for
routine investigationso Hypothermiao Neck abrasionso o Not effect for V.L.B.W
Negative Pressure Ventilator
Positive pressure ventilators:
Classification (by cycling mode);
• Time cycled: o Electrical e.g; Sechrist, Bourns BP 200, o Healthdyne 100,Bear Cub, o Pneumatic e.g; Baby bird
• Volume cycled:o e.g.; Siemens,Bourns LS-104-150, Bonnett,Emerson
• Pressure cycled
• Flow cycled
• Mixed cycling
Positive Pressure Ventilator
High Frequency Ventilators: Delivers small gas volumes at high frequency.
Classification of positern press ventilatoron (by cyclic mod)
Volume cycledPressure cycledTime cycledMined cycled
Satisfactory ventilator
All models of ventilation, should be Simple, Reliable, Small, Inexpensive, Wide range of respiratory rate upto 150, FiO2 21 to 100%, Alarm system etc.
“IT IS NOT THE GUN BUT MAN BEHIND THE GUN”
1965 Lancet editorial: • The tedious argument about the virtues of
respirators not invented over those readily available can be ended now that it is abundantly clear that the success of such apparatus depends on the skill with which it is used.
Mode control mode
Control mode: Ventilator will take total control Assist mode Ventilator initiate inspiration when
pt generates sub base line pressure trigger level
Asst/cont. Mode: Vent is set at certain level and its
responds to all breathing efforts by the patient reaching trigger level. If patients rate falls below preset rate it will automatically enter control mode.
IMV: Control mode + unhandled
spontaneous ventilation by the pt. SIMV: CPAP: Maintain increased transpulomanary
pressure during expiratory phase of respiration.
Ventilation settings Flow Rate:• 7L/min (4-10L/min)• High flow rate when inspiratory time shortened • A minimum flow of at least two times the infant
calculated minute ventilation (tidal Volume * RR) e.g. 10 Kg 70 50/3.50L/min 1:E Ration 1:1: to 1:2
2. Oxygen Con (FiO2: 50-70%
3. Peak Inspiratory pressure (PIP) 20-25cmH2O range (5 to 10 cm H2O)
4. Respi ratory rate frequency (f): varies 2-150/min range
5. Positive end expiratory pressure (PEEP): 4-7 cm/H2O
6. Wave form range: taper(sin) to square
Mean air way pressure 5.0 to 80 cm H2O the mean of installations readings of press with in the air way
Bar graph patient pressure display
Breath status indicator
D/C power indicator
Battery power indicator
Visual Alarm indicator
Message display
Alarm setting indicator
Alarm Delay setting /display
Means R/R
Trigger/Sensor sensitivity setting display
Set respiratory display.