Mechanical Ventilator

Question 1

This mode allows patients with an intact respiratory drive to exercise inspiratory muscles between assisted breaths, making it useful both supporting and weaning intubated patients. (Harrison’s 19th edition, pp 1741)

Answer 1

(Harrison’s 19th edition, pp 1741)

Synchronized Intermittent Mandatory Ventilation (SIMV)

Question 2

Most widely used mode of ventilation. (Harrison’s 19th edition, pp 1741)

Answer 2

Assist-Control Ventilation (ACMV)

Question 3

Static pressure in the airway at the end of inspiration. (Harrison’s 19th edition, pp 1743)

Answer 3

Plateau pressure

Question 4

Protective ventilator strategy. (Harrison’s 19th edition, pp 1743)

Answer 4

Target tidal volume close to 6mL/kg of IBW
Prevent plateau pressure exceeding 30cmH2O
Use the lowest possible fraction of inspired oxygen (FIO2) to keep the O2 saturation >/= 90%
Adjust PEEP to maintain alveolar patency while preventing overdistention and closure/reopening

Question 5

Conditions as indication amenability to weaning. (Harrison’s 19th edition, pp 1743)

Answer 5

Lung injury is stable or resolving
Gas exchange is adequate with low PEEP/FIO2 (<8cmH2O) and FIO2 (<0.5)
Hemodynamic variables are stable (no longer receiving vasopressors)
Capable of initiating spontaneous breathing