Week 5: Self Study: Mechanical Ventilation

Question 1

what is mechanical ventilation?

Answer 1

• a device used to fully/partially assist pts who have lost ability to maintain gas exchange through pos pressure ventilation
• air is pushed or forced into pts lungs
• expiration occurs passively but may be supported through PEEP

Question 2

indications for mechanical ventilation

Answer 2

VOPS
- ventilation (ineffective) hypercapnia or hypoxemia
- obstruction: bypasses the obstruction
- protection: absence of cough or swallow reflex
- secretion: management of excessive secretions

Question 3

goals of mechanical therapy

Answer 3

• provide adequate oxygenation and ventilation
• reduce a pt’s work of breathing
• may improve cardiac function by decreasing pre load, after load, and metabolic demand

Question 4

pressure/volume relationship

Answer 4

• direct relationship -> as pressure increases, volume increases
• ventilators can be set to increase at either a preset volume or preset pressure
• in stiff lungs, a preset volume, can lead to large increase in pressure leading to barotrauma

Question 5

extubation criteria

Answer 5

• normal ABG
• medically improving
• awake and managing secretions
• cuff leak
• passed SBT (spontaneous breathing trial)
• often pts will approach settings of PS of 5 and PEEP of 5

Question 6

possible complications of mechanical ventilation

Answer 6

• barotrauma which can result in alveolar distention, inflammation and in severe cases pneumothorax
• infection (ventilator acquired pneumonia - keep head of bed raised by 30 deg)
• diaphragmatic and respiratory muscle atrophy
• trauma, wounds, and oxygen toxicity

Question 7

what may sound alarms?

Answer 7

• coughing, gagging, or excessive secretions
• tubing disconnection or failure to deliver a breath
• high or low resp rate

Question 8

high pressure limit

Answer 8

• secretions in endotracheal tube
• condensation in tubing
• kink in ventilation tubing
• pt coughing, gagging, or trying to talk
• increase pressure from bronchospasm or pneumothorax
• chest PT

Question 9

low pressure

Answer 9

• ventilator tubing is not connected
• displaced endotracheal tube or tracheostomy tube

Question 10

high resp rate

Answer 10

• pt is experiencing anxiety or pain
• secretions in endotracheal tube or airway
• hypoxia
• hypercapnia

Question 11

low exhaled volume

Answer 11

• ventilator tubing is not connected
• leak in the cuff or inadequate seal
• occurence of another alarm prevention a full delivery of a rbeaht
• during suction