Unit 2: Mechanical Ventilation

Question 1

When is Mechanical Ventilation Required?

Answer 1

when a patient cannot maintain adequate ventilation and/or perfusion

Question 2

Indications for Mechanical Ventilation

Answer 2

• acute respiratory failure
• heart failure
• exacerbation of COPD
• protection of the airway d/t cardiac arrest, drug overdose, or respiratory depression
• spinal cord or neurological trauma

Question 3

Goal of Mechanical Ventilation

Answer 3

• support the patient until the underlying pathophysiological process is corrected
• not a cure, but supportive care

Question 4

What happens once the underlying condition is corrected?

Answer 4

• mechanical ventilation may be D/C
• patients who cannot support their own ventilatory needs or who cannot maintain optimal oxygenation may require mechanical ventilation on a permanent basis

Question 5

Members of the Team for someone who is Mechanically Ventilated

Answer 5

when patient requires mechanical ventilation, interprofessional collaboration is required to meet the needs of the patient

• nurse
• primary healthcare provider
• respiratory therapist
• dietician
• physical therapist
• social worker

Question 6

What is the Nurses Role for someone who is mechanically ventilated?

Answer 6

• continuous monitoring and assessment
• preventing complications from mechanical ventilation
• monitoring the equipment for any problems
• provide emotional support to patient and family

Question 7

Mechanical Ventilator Settings

Answer 7

prescribed ventilator settings; adjusted on the basis of patients response
-nurse and respiratory therapist work collaboratively w/ healthcare provider in adjusting ventilator settings to meet the needs of the patient

Question 8

Typical Ventilator Settings Include?

Answer 8

• Fraction of inspired oxygen (FiO2)
• Breath rate (f)
• Tidal volume (Vt)
• Flow
• Positive-End Expiratory Pressure (PEEP)

Question 9

Ventilator Settings: Fraction of inspired oxygen (FiO2)

Answer 9

amount of oxygen the patient is receiving via the mechanical ventilator

• 21%-100%
• may be started at 100% if pt extremely hypoxic; decreased on basis of ABG results
• Goal: maintain a PaO2 above 60% mm Hg and SaO2 above 90-90% at the lowest possible oxygen setting

Question 10

Ventilator Settings: Rate (f)

Answer 10

number of respirations/breaths per minute the patient receives via ventilator

• 8-12 breaths/min
• may be gradually decreased in a pt who is breathing spontaneously until the patient is able to maintain adequate ventilation
• when respiratory rate on a mechanical ventilator is assessed, document numbers of both ventilator and spontaneous breaths

Question 11

Ventilator Settings: Tidal Volume (Vt)

Answer 11

amount of preset air that is delivered with each breath

• 8 to 10 mL/kg
• based on body weight
• adjustments made from ABG results
• large amounts of Vt may cause barotrauma (injury to the lungs caused by positive pressure) or increase the risk for ventilator-associated lung injury

Question 12

Ventilator Settings: Positive End-Expiratory Pressure (PEEP)

Answer 12

positive pressure applied at the end of expiration to help prevent alveolar collapse, assist patent alveoli, and redistribute fluid from the alveoli
-improves oxygenation, allowing the FiO2 levels to be lowered

Question 13

Ventilator Modes: Controlled Mechanical Ventilation (CMV)

Answer 13

• used in patients who are unable to sustain ventilation; weak respiratory muscles
• delivers preset rate and volume of breaths per minute by ventilator independent of the patients respiratory effort

Question 14

Ventilator Modes: Assist-Control Ventilation

Answer 14

• if the patient does not initiate a breath, the ventilator delivers a preset rate and volume
• if the patient does initiate a breath, the ventilator delivers the preset volume (assisted breath), allowing patient to control the rate of breaths

Question 15

Ventilator Mode: Intermittent Mandatory Ventilation

Answer 15

• combination of ventilator-assisted breaths and spontaneous breaths of the patient regardless of the patients effort
• for patients who can breathe spontaneously but at a volume and/or rate that does not meet adequate oxygenation

Question 16

Ventilator Modes: Synchronized Intermittent Mandatory Ventilation (SIMV)

Answer 16

used for patients who are being weaned

• if patient does not initiate a breath, the ventilator delivers a preset volume and rate
• some times used w/ pressure support ventilation

Question 17

Ventilator Modes: Airway Pressure-Release Ventilation

Answer 17

designed for spontaneously breathing patients who require a high level of pressure to effectively recruit alveoli
-used with CPAP that is interrupted by pressure release to a lower pressure

Question 18

Ventilator Modes: Pressure-Support Ventilation

Answer 18

independent mode or in conjunction with CPAP or SIMV.

• This mode gives a set positive pressure during spontaneous inspirations;
• pt breaths spontaneously w/ patient’s own volume, rate, and inspiratory time but has continuous positive pressure that is maintained during inspiration
• assists in reducing the workload of breathing and keeping the alveoli open
• when used for weaning, the pressure support helps the patient to overcome the dead space ETT

Question 19

Complications Associated with Mechanical Ventilation

Answer 19

• hypotension
• infection
• barotrauma
• aspiration
• ventilator-associated pneumonia (VAP)

Question 20

Ventilator Alarm Systems

Answer 20

• alarm indicates when there is a need for intervention
• nurse required to monitor
• nurse immediately assesses the patient and the ventilator to find out what is interfering w/ the ventilator and causing the alarm
• High-pressure alarm
• Low-pressure alarm

Question 21

Safety Alert: Ventilator Alarm

Answer 21

• alerts the nurse that something is wrong w/ the pressure, volume, or rate of air being delivered to the patient
• when alarm is activated, the nurse’s responsibility is to immediately check the patients ventilation and oxygenation; priority is patient first then ventilator
• if nurse cannot immediately identify the problem, nurse disconnects the patient from the ventilator and uses a manual resuscitation bag to ventilate the patient while calling for assistance
• failure to ensure adequate ventilation = injury to the pt (anoxic brain injury or death)

Question 22

Causes for the High-Pressure Alarm

Answer 22

> Mucous Plug or increased secretions
-suction PRN
Patient biting the ETT
-insert an oral airway to prevent biting
Pneumothorax
-assess for asymmetrical chest rise and decreased breath sounds over the pneumothorax site; contact health care provider immediately
Patient anxious and fighting the ventilator
-assess the patient, provide emotional support, reevaluate sedation/analgesic need
Kink in tubing
-assess tubing from ventilator to patient to ensure no kinking of the tube is present
Water collected in the ventilator tubing
-empty water from the ventilator tubing

Question 23

Causes for the Low-Pressure Alarm

Answer 23

> Cuff leak
-assess for cuff leak, check cuff pressure; call for respiratory and healthcare provider
Leak in the ventilator circuit
-assess all connections and tubing
Patient stops breathing in the pressure support modes or SIMV
-assess patient notify health care provider

Question 24

Nursing Interventions: Actions

Answer 24

• HOB elevation between 30 and 45 degrees unless contraindicated
• Clear airway secretions w/ suctioning, CPT, frequent position changes, and increasing activity
• Daily “sedation vacation” and readiness-to-wean assessment
• Peptic ulcer disease prophylaxis; meds that reduce gastric activity
• DVT prophylaxis
• Daily oral care w/ chlorhexidine

Question 25

Prevention of Ventilator-Assisted Pneumonia (VAP)

Answer 25

• assess readiness to extubate daily through combined spontaneous awakening trials (SATs; sedation interruption/minimization) and spontaneous breathing trials (SBTs)
• early exercise and mobility
• elevate HOB 30 to 45 degrees
• minimize pooling of secretions above the endotracheal tube cuff by using an endotracheal tube w/ subglottic suction capability in patients w/ anticipated intubation greater than 48 to 72 hours
• change ventilator circuits only if visibly soiled; do not change routinely
• perform oral care using chlorhexidine
• use ventilator bundles to reduce ventilator-associated events (VAE) and VAP

Question 26

Connection Check: The nurse is screening patients for their risk of developing VAP. The nurse considered which patient at greatest risk?
A. a patient who was extubated within 24 hours of being intubated
B. a patient intubated and placed on mechanical ventilation less than 72 hours ago
C. a patient w/ the HOB elevated 45 degrees
D. a patient who was placed on nasal cannula after being extubated

Answer 26

B. patient intubated and placed on mechanical ventilation less than 72 hours ago