Student Clinical Knowledge Evaluation 3 Flashcards
Mechanical Ventilation: Indications (4)
- IVF (VC < 10mL/kg, MIP > -20cmH2O, RSBI > 105,
VT < 5mL/kg, RR > 35, VE > 10L) - AVF (pH < 7.20, PACO2 > 55, Apnea
- Prophylactic (CHI, Smoke Abd/Thoracic surg)
- Severe Oxygenation Issues (P/F < 200, P(A-a)O2 on 100% O2 > 350, PaO2 < 60 on > 50%)
Mechanical Ventilation: Hazards/Complications/Precautions (3)
- Decreased CO, VR, and urine output, decreased gastrointestinal and liver perfusion and function
- Increased ICP
- Barotrauma from pressures
Tidal Volume Settings: Normal and ARDS
Normal: Vt 6 -8 ml/kg
ARDS: Vt 4 -8 ml/kg
Types of Ventilation/Presets and Varied
- Volume: Preset Volume & Rate, Pressures vary
- Pressure: Preset Pressure & Rate, Volumes vary
Ventilation Terms
1. Trigger
2. Cycle
3. Limit
- Trigger: Initiates the breath
- Cycle: Ends the inspiratory breath - can be pressure, volume, flow, time
- Limit: Stops the inspiration early - can be pressure, volume, flow, time
Vent Modes (4)
- CMV
- IMV
- CSV
- Dual Mode
CMV
Types: (3)
- CMV - Control or Assist
- VC - CMV
- PC - CMV, PCV
CMV - Control / Assist
1. How it works
2. Trigger’s
3. Other info
4. Hazards
- All breaths are mandatory and can be volume or pressure targeted
- a) Control Mode: Time Trigger
b) Assist Mode: Time, Flow, Pressure - a) Control Mode: All machine breaths. Pt. cannot trigger. Only used when Pt. cannot make an effort to breath
b) Assist Mode: Pt. can trigger the vent, but will get a set volume or pressure with every breath - a) CM Hazards: Cruel mode if Pt. is conscious
b) AM Hazards: Sometimes difficult to prevent Resp Alkalosis without the use of Resp depressant or muscle relaxer. IMV mode may help
VC - CMV
1. How it works
2. Trigger’s
3. Other info
4. Hazards
- Preset Volume and Rate with pressures varying
- Triggers - Time, Flow, Pressures
- None
- Need to monitor and adjust Pts. inspiratory flow by looking at the pressure-time curve for smooth and rapid peak
PC - CMV, PCV
1. How it works
2. Trigger’s
3. Other info
4. Hazards
- Preset Pressure and Rate with Volumes Varying
- Triggers - Time, Flow, Pressures
- a) Mode indicated when PIP > 40 CMH2O, Plat > 30 CMH2O on volume mode
b) Set the preset pressure by the plateau pressure on CMV or you take PIP - PEEP - None
IMV
Types: (2)
- IMV
- SIMV
IMV
1. How it works
2. Trigger’s
3. Other info
4. Hazards
- Pt. is able to breathe spontaneously between machine breaths getting their own spontaneous Vt.
- Triggers - Time, Flow, Pressure
- Can be PC or VC Mode - IMV modes can also use PS to assist with spontaneous breaths
- Lack of coordination between mandatory and spontaneous breaths causes breath stacking
SIMV
1. How it works
2. Trigger’s
3. Other info
4. Hazards
- This allows for spontaneous breaths and tries to synchronize with the patient whenever possible - preventing breath stacking
- Triggers - Time, Flow, Pressures
- Can be PC or VC Mode - IMV modes can also use PS to assist with spontaneous breaths
- None
CSV
Types: (3)
- CPAP
- PSV
- APRV
CPAP
1. How it works
2. Trigger’s
3. Other info
- All breaths are spontaneous at an elevated baseline pressure to recruit and distend alveoli
- Triggers - Flow or Pressures
- None
PSV
1. How it works
2. Trigger’s
3. Other info
- All breaths are spontaneous - Preset Pressure, Vt varies
- Trigger - Flow or Pressures
- Adjust to obtain Vt 5-7 ml/kg and RR < 28
APRV
1. How it works
2. Trigger’s
3. Other info
- Breaths are spontaneous - uses 2 levels of PEEP. Pt. breaths spontaneously at high PEEP to recruit alveoli and improve oxygenation. The high PEEP is released periodically to a low PEEP. Low PEEP is < 1.5 sec and allows for CO2 removal
- Triggers - Flow or Pressures
- Used in ARDS
a) HiPEEP - Set at previous Plat Pressure
b) LPEEP - Set at 0
c) HiPEEP - Set at Max 15 sec and Min 4 sec
d) TLow - Set between 0.5 - 1.0 sec
Dual Mode
Type: (1)
- PRVC
PRVC
1. How it works
2. Trigger’s
3. Other info
- Vt is used as feedback mechanism to control the preset pressure control level
- Triggers - Time, Flow, Pressures
- Pressure will increase or decrease by 3 CMH2O to maintain Vt. If Vt is low, the machine will increase until Vt is achieved. Highest pressure can go is within 5 of HPL
Vent Troubleshooting
Alarm Types: (7)
- High Pressure Limit
- Low Pressure Alarm
- Low PEEP
- Low Tidal Volume (Vt)
- FiO2
- Minute Volume Alarm
- Apnea Alarm
Vent Troubleshooting
High Pressure Limit (10)
Causes & How to Fix
- Coughing: AMBU/Auscultate
- Secretions: Suction
- Bronchospasms: Bronchodilator
- Water in Circuit: Drain Circuit
- Herniated ETT Tube: Deflate Cuff, Inflate
- Kinked Tubing: Unkink
- Pneumothorax: Chest Tube
- Blocked Exhalation Manifol: Unblock
- Mainstem Bronchial Intubation: Pull the tube back until 3-4 cm above Carina
- Pleural Effusion: Thoracentesis or Chest Tube
Vent Troubleshooting
Low Pressure Alarm (4)
Causes & How to Fix
- Loss of System Pressure: Power Failure, Gas Failure
- Loss of Circuit Pressure: Disconnect, Exhalation valve disconnect, ETT Cuff Volume Loose Circuit, Loose Humidifier
- Premature Termination: Excessive Peak Flow, Insufficient Inspiratory Time
- Inappropriate Vent Setting: Low pressure limit is set too high. Low Tidal Volume is set to high
Vent Troubleshooting
Low PEEP (1)
Causes & How to Fix
- Leaks, High Inspiratory Flows: Adjust Peak Flows, Look for Leaks
Vent Troubleshooting
Low Tidal Volume (Vt) (1)
Causes & How to Fix
- Leaks: Check for leaks or ETT cuffs