N470: Mechanical ventilation

What are the two normal breath sounds?

1) bronchial

2) vesicular

breath sounds heard over the tracheobronchial tree

bronchial breathing

breath sounds heard over the lung tissue

vesicular breathing

adverse lung sounds resulting from small airways suddenly snapping open. Usually indicates fluid in the lungs

crackles

Small clicking, bubbling or rattling sounds in the lungs heard with inhalation. Believed to occur when air opens closed air spaces. can also be described as moist, dry, fine, and course

rales

lung sounds that resemble snoring. occurs when air is blocked, or air flow becomes rough through the large airways/ bronchioles

rhonchi

high-pitched lung sounds produced by narrow airways often heard with exhalation

wheezing

wheeze-like lung sounds produced by a narrow airway/trachea (life-threatening)

stridor

lack of lung sounds unilateral, bilateral, bases, or upper

absent lung sounds

Eupnea

normal breathing

intensive deep breathing

hyperpnea

type of breathing in which you consciously use your diaphragm to help you take deep breaths; common in COPD when accessory muscles become more rigid

diaphragmatic breathing

a mode of breathing that requires contraction of the intercostal muscles

costal breathing

a breathing exercise that helps you slow your breathing and inhale and exhale more air; slowly inhale through your nose, and gently exhale through pursed lips; makes it easier to do physical activities and reduce stress

pursed lip breathing

Early symptoms of hypoxia*

A- anxiety

T- tachycardia

R- restlessness

I- irritability

A- apprehensive

Late symptoms of hypoxia

1) cyanosis

2) cool clammy skin

3) use of accessory muscles with retractions,

4) hypotension

5) arrythmias

6) LOC

7) seizures

8) coma

Types of oxygen delivery devices

-nasal cannula

-high-flow nasal cannula

-simple face mask

-venturi mask

-non-rebreather

-CPAP/BiPAP

nasal cannula ideal L/min

4-6 L/min

nasal cannula liters and FiO2 range

1-2L= 24-28%

3-4L= 32-36%

5-6L= 40-44%

>6= no change in FiO2

High flow nasal cannula

delivers up to 60 L/min enabling 100% FiO2 and true positive pressure (6 cm water of PEEP); has special tubing with humidification and warming

Which oxygen delivery systems are titratable and which are not?

Titratable: nasal cannula, high flow nasal cannula, simple face mask, venturi mask

Not: nonrebreather

Which oxygen delivery device requires high flow to prevent CO2 rebreathing? 75% of inspired volume is from room air and it is for short term use

simple face mask

L/min range and FiO2 delivered with the simple face mask

8-12L/min and 35% FiO2

Which oxygen delivery device minimizes CO2 buildup, and is very accurately titrated with an adapter

venturi mask

Flow and FiO2 delivered with a venturi mask

4-10L/min and 24-50% FiO2

Which oxygen delivery device has one-way valves to prevent exhaled air from returning to the bag and is used for rapid desaturation?

Nonrebreather mask

Nonrebreather mask flow and FiO2

10-15 L/min (Max setting) and 95-100% FiO2

What are the types of non-invasive mechanical ventilation?

CPAP and BiPAP

What is the physiologically normal Cpap or PEEP?

5 cm H2O

What does Cpap stand for?

continuous positive airway pressure

What does Bipap stand for?

bilevel positive airway pressure

What is the consequence of low vs high Cpap/PEEP?

Low= alveolar collapse

High= increased thoracic pressure and potentially impeded venous return to heart

What disorders is Cpap used for?

moderate to severe sleep apnea

What disorders is Bipap used for? (3)

- CHF

- neuromuscular disease (ex: ALS)

- COPD

Provides continuous air pressure at a medically suggested level to treat various types of respiratory disease

Cpap

Provides different levels of pressure during inhalation and exhalation

Bipap

describe the two levels of Bipap

Cpap (to keep alveoli open) + pressure support during inspiration (to decrease work of breathing and increase inspiratory volume)

How long can a patient have an endotracheal tube (ETT)?

1-2 weeks max

Assessment for an ETT (6)

1) check marked points on tube at insertion (gums or teeth) to make sure it hasn't moved

2) inspect positioning and stabilization of tube (to prevent airway obstruction or tissue necrosis)

3) support clients head and tube when turning

4) reposition oral ETT to opposite side daily documenting tube depth each time

5) inspect and clean the mouth, observe for pressure areas

6) provide suction toothbrushing Q12H or swabbing Q2H and oropharyngeal sub-glottal suctioning Q6H (to prevent pulmonary infection)

ETT documentation

1) size of tube

2) position related to gums and lips

3) position related to which side of the mouth

4) assessed ETT cuff volume and pressure (done by RN or RT)

5) securing ETT (position, change date (done by RT or RN)

Methods to suctioning an ETT

- closed suction

- open suction with a sterile catheter kit

What is the leading cause of death in the ICU?

Ventilated associated pneumonia (VAP)

5 elements of the VAP prevention bundle*

1) age-appropriate oral care

2) proper airway suction technique

3) maintenance of safe ETT cuff pressures

4) application of aspiration precautions

5) HOB elevation (20-30 degrees)

Preparation for extubating

-FiO2 (don't deliver more than 60%)

-mode of ventilation

-weaning parameters

-protection of airway

-LOC

-ability to cough

Safety considerations for oxygen delivery (9)

1) no smoking

2) non-flammable gowns

3) remove anything that might ignite

4) remove friction-type or battery-operated toys

5) all electrical equipment should be properly grounded

6) remove volatile/flammable materials

7) locate fire extinguishers on unit

8) locate oxygen meter turn off lever

9) if using tank, place in approved carrier

The three modes for ventilators (3)*

1) assisted volume control (A/C)

2) synchronous intermittent mandatory ventilation (SIMV)

3) continuous positive airway pressure (CPAP) with pressure support

Most common settings for a ventilator

1) RR

2) TV (tidal volume)

3) FiO2 (fraction inspired oxygen)

4) PS (pressure support)

5) PEEP (positive end-expiratory pressure)

normal PEEP range

4-10 sometimes 15-20 cm H2O

parameters to monitor for TV on a vent

- 5-8 ml/kg

- low tidal vol ventilation protects from ventilator associated complications

parameters to monitor FiO2 on a vent

Should be kept below 0.5 or 50% to avoid oxygen toxicity, but up to 100% can be used in some circumstances

parameters to monitor RR on a vent

should be set to at least 1 breath very 5 sec or 12 respirations/min

parameters to monitor pressure support on a vent

should be between 5 (minimal support) and 30 (total support)

what is pressure support on a vent?

provides positive pressure during inhalation to decrease work of breathing

parameters to monitor Expiratory Tidal Volume on a vent

- ranges from 100-600 ml depending on size of patient

- only measured on spontaneous breaths!

- easier to measure than inspiratory but reflects how much air they are getting

- if this is too low, increase pressure support or RR

parameters to monitor PIP (peak inspired pressure) on a vent

- normal is 25-30 cm H20

What is PIP?

Peak inspiratory pressure, this is the pressure it takes to push air into the lungs

A controlled mode delivers a preset RR and TV, each additional breath will be delivered a preset TV

Assist volume control (A/C)

which type of ventilation is used for patients who require full ventilatory support?

Assist volume control (A/C)

Does A/C have pressure support? Why?*

A/C has NO pressure support- applied during inspiration, A/C has no spontaneous breathing

A type of mechanical ventilation that has a preset RR and TV in which the patient can trigger a breath and have spontaneous TV; ventilator breaths are synchronized with patient's respiratory effort

synchronous intermittent mandatory ventilation (SIMV)

which type of ventilation is used for patients that have some ability to breathe spontaneously but are not able to maintain an adequate minute ventilation

SIMV

which type of ventilation is used to help wean patients from mechanical ventilation?

SIMV

Does SIMV have pressure support? why?

SIMV does use pressure support during inspiration to assist breathing

A type of mechanical ventilation in which the RR and TV are a function of patient effort and the patient is breathing spontaneously with a positive pressure applied throughout the respiratory cycle

CPAP with pressure support

which type of ventilation is used for patients that are breathing spontaneously and need to improve oxygenation

CPAP with pressure support

Different types of alarms for a vent (4)

- high pressure (check for disconnect; if PIP is too high; vent will stop automatically)

- low pressure (check for disconnect; could be low PEEP)

- high RR

- low exhaled volume

The low pressure alarm on your patient's vent is triggered. You cannot find a disconnect in the system, your next action is to:

a) manually bag the patient until the cause is determined

b) suction the pt

c) reset the alarm limits

d) bypass the alarm

a) manually bag the patient until the cause is determined

which of the following about PIP is false?

a) PIP should not be monitored and documented along with vital signs on a vented patient

b) patients who have an increasing trend in PIP is potentially developing ARDs

c) increased PIP may be due to- kinks in tubing, patient fighting the vent, patient with pain or anxiety, decreased lung compliance, or increased lung secretions

d) increased PIP is directly related to increased risk of barotraumas

a) PIP should not be monitored and documented along with vital signs on a vented patient

Which clinical situation requires mechanical ventilation?

a) a patient in respiratory arrest

b) patients who have both respiratory and cardiac failure

c) patients with brain injuries

d) all of the above

d) all of the above

A patient is on CPAP, 40% FiO2, PEEP of 10, and pressure support of 15 has a respiratory rate of 40 and is diaphoretic. This patient is a perfect candidate for extubating.

True/false

false

Parameters that must be monitored on a vent

1) RR

2) TV (tidal volume)

3) FiO2 (fraction inspired oxygen)

4) PS (pressure support)

5) PEEP (positive end-expiratory pressure)

6) expiratory tidal volume

7) PIP (peak inspired pressure)

(vent settings + 2 more)

How often do you do suctioning for an ETT tube?

provide suction toothbrushing Q12H or swabbing Q2H and oropharyngeal sub-glottal suctioning Q6H