Modes of Ventilation Flashcards
Difference between BiPaP and CPAP
Indications for CPAP
patients without resp failure
*sleep apnea
Indications for Bipap
Patients with impending or existing respiratory failure
*bridge to mv
What does IPAP improve?
- improve tidal volume
- thus decreasing CO2
What does EPAP improve?
- improve FRC
- Helps recruit more alveoli thus increasing O2,may reduce work of breathing associated with autopeep
Indications for N/V
-
Restrictive disease
- Pregnancy
- Neuromuscular disease
- Obesity
-
Obstructive Disease
- COPD
N/V not indicated
- Asthma
- Pneumonia
N/V SETUP/ SETTINGS
CHART
I:E ratio
COPD
1:2 TO 1:3
I:E RATIO
OHS, NM & CWD
1:1
INSPIRATORY VOLUME
COPD
OHS, NM, & CWD
COPD: 0.8 - 1.2s
OHS, NM, & CWD: 1.2 - 1.5S
Four phases of the ventilatory cycle
- Inspiration
- Inspiration to expiration
- Expiration
- Expiration to inspiration
Trigger
FLOW VS PRESSURE
LIMIT
Determines the size of the breath
* normally associated with volume-controlled ventilation
CYCLE
Determines what actually ends the breath
PSV
FLOW IS CYCLE
VCV and PCV
TIME IS CYCLE
PCV
- less barotrauma
- esp. with pediatrics
Volume cycled; volume-controlled
- preset volume
- DOES NOT ELIMINATE THE WORK OF BREATHING
Assist- Control Ventilation
- if not breathing go to CMV
- if breathing too rapidly go to SIMV
What is this?
assisted breath
What does SIMV allow a patient to do?
Dr. Massie often put LMA with PS
if they are not breathing after the induction meds she puts her patient on SIMV OR PC
one they go above that pressure she changes them
- BETTER THAN CMV
How is the patient’s compliance tested?
most sensitive is when we bag the patient
if lung compliance is lower what happens to pressure?
compliance is lower = higher pressure
Change in Pressure/change in volume =
compliance
What is compliance?
measure of distensibility
how is compliance expressed?
change in volume for given change in pressure
Vt (Paw-Peep)
What is normal compliance?
What is compliance in ARDS?
70 - 100 ml/cm H20
<40-50 ml/cm H2O
What is FeO2?
what the patient is expiring and it should equilibrate
with your FiO2
* we are always trying to reach equilibrium
What is normal lung compliance?
5-7 ml/kg with IBW
If your patient is obese what will be your TV?
lowered end of 5-7 ml/kg
so ill use the 5 ml because of abnormal lung compliance (ARDS pulmonarycontusion)
what is the normal MV?
5-10 L/ M
MV= TV*RR
SENSITIVY SLIDE
also known as trigger and percent trigger
Inspiratory flow rate is..
what causes barotrauma?
- NOT GAS FLOW
- >75
Why do we add PEEP?
GOAL: To reach the best arterial oxygenation with the least decrease in cardiac output and maintenance of acceptable airway pressure
How do we assess PEEP?
we are looking for
OPTIMAL PEEP - point of maximal alveolar recruitment (MAR)
- Increase PEEP to point of lung inflation at which compliance decreases
- observe airway pressure with each increase in PEEP
- PIP should rise only by the amount of PEEP dialed in; when PIP rises more than PEEP, alveoli overdistended and point of MAR exceeded
What are SE of PEEP?
- Barotrauma
- Decrease in CO
- Incorrect filling pressures
- If PEEP applied subtract 1/2 of the PEEP over 5 from PCWP
How to increase MEAN ARTERIAL PRESSURE?
- Increase respiratory flow rate
- Increase peak inspiratory pressure
- Increase in inspiratory time
- Increase in PEEP
Pressure Support Ventilation
slide*
Pressure- Controlled/ Limited Ventilation
- If you have gradually increasing Peak Inspiratory Flow switch to Pressure Controlled to see how it will decrease it
- Dr. Massie use this on her LMA
- good for neonatal
- good for NMD with normal lungs
