CRITICAL CARE: OXYGEN/MECHANICAL VENTILIATION

Question 1

MECHANICAL VENTILIATION

OVERALL PURPOSE: (3)

Answer 1

1. •Provides breathing support
2. •Humidified O2
3. •Positive pressure: Keeps alveoli open during inspiration and prevents alveolar collapse during expiration

Question 2

1. •FiO2 =
2. •Tidal volume =
3. •Rate =
4. •Inspiratory/expiratory ratio =
5. •Flow rate =
6. •Sensitivity =
7. •High pressure limit =
8. •Pressure support =
9. •Positive End-expiratory pressure =

Answer 2

1. •FiO2 = amount of oxygen delivered
2. •Tidal volume = volume of gas delivered (5-8ml/kg)
3. •Rate = minimal # of breaths per minute
4. •Inspiratory/expiratory ratio = 1:2 (may be reversed with non-compliant lungs0
5. •Flow rate = speed of the volume
6. •Sensitivity = the negative inspiratory pressure the patient must generate
7. •High pressure limit = vent will not exceed this limit…
8. •Pressure support = Positive pressure to decrease the patients work
9. •Positive End-expiratory pressure = positive pressure left in lungs

Question 3

1. Tidal vol usually set by ?
2. Rate increase in response to ? or ?
3. Babies I/E Ratio?
4. Kussmauls I/E Ratio?
5. Sensitivity: ?
6. Pressure support: ?
7. Positive End-expiratory pressure: ?

Answer 3

1. Tidal vol usually set by weight
2. Rate increase in response to alkalosis or acidosis
3. Babies 1:1 I/E ratio
4. Kussmauls 1:1
5. Sensitivity: how much are you sucking in before vent kicks in?
6. Pressure support: Positive pressure how much you are going to support the pt
7. Positive End-expiratory pressure: PEEP

Question 4

1. Tidal Vol Normal
2. Tidal Vol with mechanical vent

Answer 4

1. Tidal volume during normal spontaneous breathing equals 5 ml/kg. Employment of this volume during mechanical ventilation results in atelectasis which can be avoided by using intermittent sighs.
   
   • Large tidal volumes of 10-15 ml/kg may produce alveolar injury
   • Preferred tidal volume = 7-8 ml/kg on vent

Question 5

The major indication for mechanical ventilation is acute respiratory failure, of which there are two basic causes:

Answer 5

The major indication for mechanical ventilation is acute respiratory failure, of which there are two basic causes:

Ventilatory (Hypercapnic respiratory failure)

Reduced respiratory drive
Chest wall abnormalities
Respiratory muscle fatigue

Inefficient Gas Exchange (Hypoxic respiratory failure)

Intrapulmonary shunt
Ventilation-perfusion mismatch
Decreased FRC

Question 6

Goals of Mechanical Ventilation (6)

Answer 6

Goals of Mechanical Ventilation

1. Relieve respiratory distress
2. Decrease work of breathing
3. Improve pulmonary gas exchange
4. Reverse respiratory muscle fatigue
5. Permit lung healing
6. Avoid complications

Question 7

Controlled Mandatory Ventilation

Controlled mandatory ventilation delivers

1. a set__?__and
2. set ___?___
3. Used for clients with what status? (3)

Answer 7

Controlled mandatory ventilation delivers a set tidal volume and a set rate. It is used for clients who are chemically paralyzed and sedated or whose neurological status has deteriorated to the point that no drive to breathe exists

Question 9

Assist control ventilation

Assist control ventilation delivers a set __?__ at a set rate, but allows clients to take __?__breaths. When they take their own breaths, they receive the entire __?__, thus decreasing __?__. If the rate is set high enough, it is essentially the same as controlled mechanical ventilation.

Answer 9

Assist control ventilation delivers a set tidal volume at a set rate, but allows clients to take spontaneous breaths. When they take their own breaths, they receive the entire preset tidal volume, thus decreasing their work of breathing. If the rate is set high enough, it is essentially the same as controlled mechanical ventilation.