3.2a SIMV

Utilize the Data Recording Sheet that your laboratory instructor provides.

1. Setting Up the Circuit:
   • Assemble the ventilator circuit according to the simulator’s instructions. This typically involves connecting the ventilator to the artificial lung model (if used) or the syringe (simulating lung compliance) through tubing and valves.
   • Connect the manometer to the circuit to measure airway pressure.
2. Initial Settings:
   • Set the ventilator mode to SIMV.
   • Set the following initial parameters:
     • Tidal volume (VT): 500 mL
     • Respiratory rate (RR): 12 breaths/minute
     • PEEP (Positive End-Expiratory Pressure): 5 cmH2O
     • Pressure Support: 5-8 cmH2O
   • Turn on the ventilator and observe the simulated ventilation cycles.

Data Collection and Analysis:

1. Effect of Respiratory Rate:

• • Increase the respiratory rate on the ventilator to 16 breaths/minute while keeping all other settings constant.
  • Record the following data:
    • Peak inspiratory pressure (PIP)
    • Plateau pressure (Pplat)
    • Minute ventilation (Ve)
  • Repeat this step by decreasing the respiratory rate to 8 breaths/minute.

Question 1: How did the change in respiratory rate affect PIP, Pplat, and Ve? Explain why this happened.

2. Effect of Tidal Volume:

• • Set the respiratory rate back to 12 breaths/minute.
  • Increase the tidal volume to 700 mL while keeping all other settings constant.
  • Record the same data points as in Step 1 (PIP, Pplat, Ve).
  • Repeat this step by decreasing the tidal volume to 300 mL.

Question 2: How did the change in tidal volume affect PIP, Pplat, and Ve? Explain the relationship between tidal volume and airway pressures.

3. Effect of PEEP:

• • Set the tidal volume back to 500 mL and respiratory rate to 12 breaths/minute.
  • Increase the PEEP setting to 10 cmH2O while keeping all other settings constant.
  • Record the same data points as in Step 1 (PIP, Pplat, Ve).
  • Repeat this step by decreasing the PEEP to 0 cmH2O.

Question 3: How did the change in PEEP affect PIP, Pplat, and Ve? Explain the rationale behind using PEEP in ventilator management.

3.2b PS

Utilize the Data Recording Sheet that your laboratory instructor provides.

1. Setting Up the Circuit:
   • Assemble the ventilator circuit according to the simulator’s instructions. Connect the manometer to the circuit to measure airway pressure.
   • For an advanced setup, connect the flow simulator to represent patient inspiratory effort or breathe for the the vent by triggering an artificial lung.
2. Initial Settings:
   • Set the ventilator mode to PS.
   • Set the following initial parameters:
     • Pressure support (PS): 5 cmH2O
     • PEEP (Positive End-Expiratory Pressure): 5 cmH2O
     • Respiratory rate (RR): Backup rate set to 12 breaths/minute (ventilator will deliver breaths only if patient doesn’t initiate their own)
   • Turn on the ventilator and observe the simulated ventilation cycles.

Data Collection and Analysis:

1. Effect of Pressure Support:
   • Increase the pressure support level on the ventilator to 10 cmH2O while keeping all other settings constant.
   • Record the following data:
     • Peak inspiratory pressure (PIP)
     • Plateau pressure (Pplat)
     • Tidal volume (VT)
   • Repeat this step by decreasing the pressure support to 2 cmH2O.

Question 1: How did the change in pressure support affect PIP, Pplat, and VT? Explain the relationship between pressure support and lung inflation.

2. Effect of PEEP:

• Set the pressure support level back to 5 cmH2O.
• Increase the PEEP setting to 10 cmH2O while keeping all other settings constant.
• Record the same data points as in Step 1 (PIP, Pplat, VT).
• Repeat this step by decreasing the PEEP to 0 cmH2O.

Question 2: How did the change in PEEP affect PIP, Pplat, and VT? Explain how PEEP influences work of breathing in PS.

3. Simulating Patient Effort (Optional):

• If your simulator allows, connect the flow simulator to represent patient inspiratory effort.
• Observe the ventilator’s response to increased and decreased flow rates.

Question 3: How does patient effort (increased flow) affect ventilator cycling in PSV? Explain the concept of patient-ventilator synchrony.