Subject:	Laboratory XII Answers
Hi all,

	I've been asked by many to provide answers to Lab XII on initial ventilator settings.  Because this exercise requires you to place the ventilator on a test lung and obtain measured values, its not practical to generate an answer key since every situation would be different.  Use the following for parameters:

•	Mode: A/C
•	Tidal Volume: 10-12 mL/kg IBW
•	Respiratory Rate: 12-14 to allow for a Minute Volume of about 100 ml/kg or 3.5 x BSA for females or 4 x BSA for males
•	Peak Flow: VE x (I+E) or Vt/tI
•	Flow Pattern: Decelerating
•	FIO2: 100%
•	PEEP: 0 to 5 cm H2O
•	Sensitivity: If Pressure Triggering – 2 cm H2O; If Flow Triggering-3 L/Min sensitivity flow and 6 L/Min base flow if needed.
•	Alarm Settings: 
•	High Pressure: 10 to 15 cm H2O above PIP
•	Low Pressure (if available): 10 to 15 cm H2O below PIP
•	High Respiratory Rate: 10 to 15 breaths above measured rate
•	Low Tidal Volume: 10 to 20% below measured exhaled tidal volume
•	High Tidal Volume (if available): 10 to 20% above measured exhaled tidal volume
•	Low Minute Volume: 10 to 20% below measured exhaled minute volume
•	High Minute Volume: 10 to 20% above measured exhaled tidal volume
•	Low PEEP/CPAp (if available): 2 to 3 cm H2O below set PEEP
•	Apnea Settings: Set the same as in Volume-oriented ventilation.

	The answers to the blood-gas scenarios are as follows:

•	Question 1: Increase the respiratory rate to increase alveolar minute volume and decrease the PaCO2.  Assuming you started the patient on 100%, you probably should consider additional PEEP.
•	Question 2: Assuming he was started on 100%, we would need to increase the PEEP level.
•	Question 3: Decrease the set rate and/or consider the cause of the respiratory alkalosis (if she is triggering above the set rate, is it because of pain, anxiety, etc?).  Also consider terminating mechanical ventilation.
•	Question 4: Decrease the set rate and/or consider the cause of the respiratory alkalosis (as above).  Also consider terminating mechanical ventilation.

Rick Zahodnic MBA RRT-NPS RPFT AE-C
Clinical Coordinator
Respiratory Therapy Program
Macomb County Community College
(586) 286-2033