Lung expansion Flashcards
Lung expansion therapy encompasses a variety of respiratory care modalities designed to prevent or correct atelectasis
deep breathing/directed cough, incentive spirometry (IS),
continuous positive airway pressure (CPAP), positive
expiratory pressure (PEP), and intermittent positive
airway pressure breathing (IPPB)
The common purpose that all of these techniques share is to
improving pulmonary function by maximizing alveolar recruitment and optimizing airway clearance.
If all of the following therapies were to be compared,
the common factor they share is that they all are designed
to
increase functional residual capacity (FRC)
What are the two types of atelectasis
gas absorption and compression
can occur either when
there is a complete interruption of ventilation to a section
of the lung or when there is a significant shift in ventilation/
perfusion (V Q ).
Gas Absorption
When ventilation is compromised to a larger airway or bronchus,
lobar atelectasis
results when the forces within the chest wall and lung—specifically, the pleural pressure—are exceeded by the transmural pressure, which is what
distends and maintains the alveoli in an open state.2
Compression atelectasis
Compression atelectasis is primarily caused by
persistent use of small tidal volumes by the patient
Compression atelectasis results when
the patient does not periodically
take a deep breath and
expand the lungs fully
Atelectasis can occur in any patient who cannot or does
not
take deep breaths periodically and in patients who are
restricted to bed rest for any reason
It is the major
contributor to the onset of atelectasis.
It is the major contributor to the onset of atelectasis.
Diaphragmatic position and function
Anesthetized patient
there is a cephalad (toward the head) shift of the
diaphragm
Atelectasis is one of the most important determinants
of________after abdominal surgery and may account
for ____ of deaths within 6 days of surgery
hypoxemia,24%
It often provides the first clue in identifying atelectasis.
Patient medical history
When the
atelectasis involves a more significant portion of the lungs,
the patient’s. (signs)
increases proportionally. Fine, late-inspiratory crackles may be heard over the
affected lung region. Bronchial-type breath sounds. Diminished
breath sounds, Tachycardia
It is often used to confirm the presence of atelectasis.
Chest radiograph
The atelectatic region of the lung has
increased
Opacity
Direct signs of volume
loss on the chest film include
displacement of the interlobar fissures, crowding of the pulmonary vessels, and air bronchograms
Indirect signs includes
elevation of the diaphragm; shift of the trachea, heart, or mediastinum; pulmonary opacification; narrowing of the space between the ribs; and compensatory hyperexpansion of the surrounding lung
All modes of lung expansion therapy increase lung volume
by
increasing the transpulmonary pressure (PL) gradient.
gradient represents the difference between the alveolar pressure (Palv) and the pleural pressure (Ppl):
PL gradient
The purpose of IS is to guide the patient to take a sustained maximal inspiratory effort resulting in a decrease in ___________
Ppl and maintain the patency of airways at risk for closure
IS devices are designed to mimic _____ by encouraging patients to take slow, deep breaths.
natural sighing
The inspired volume goal is set on the basis of__________. The true benefit of IS is best achieved by _________.
predicted values or observation of initial performance, repeated use and proper technique
The basic maneuver of IS is a ________. An SMI is a slow, deep inhalation from the _________, followed by a ______second breath-hold.
sustained maximal inspiration (SMI), functional residual capacity (FRC) up to (ideally) the total lung capacity, 5- to 10
Indications for Incentive Spirometry
- Presence of pulmonary atelectasis
- Presence of conditions predisposing to atelectasis
- Upper abdominal surgery
- Thoracic surgery
- Surgery in patients with COPD
- Presence of a restrictive lung defect associated with quadriplegia or dysfunctional diaphragm
Contraindications for Incentive Spirometry
• Patient cannot be instructed or supervised to ensure
appropriate use of the device
• Patient cooperation is absent, or the patient is unable to understand or demonstrate proper use of the device
• Patients unable to deep breathe effectively (VC < 10 ml/
kg or IC < 13 predicted)
Hazards and Complications of Incentive Spirometry
- Hyperventilation and respiratory alkalosis
- Discomfort secondary to inadequate pain control
- Pulmonary barotrauma
- Exacerbation of bronchospasm
- Fatigue
_________ are the most frequently reported symptoms associated with respiratory alkalosis.
Dizziness and numbness around the mouth
_______ devices measure and visually indicate the volume achieved during an SMI. The most popular true volume-oriented IS devices employ a _____ that rises according to the inhaled volume
True volume-oriented, bellows
_______ devices measure and visually indicate the
degree of inspiratory flow
Flow-oriented
Successful IS requires effective ______.
patient teaching
Some patients in the early postoperative stage may need to rest for _______ between maneuvers.
30 seconds to 1 minute
healthy individuals average about sighs per hour, an IS regimen should probably aim to ensure a minimum of ______ SMI maneuvers each hour
6, 5 to 10
________ provides breathing support to patients with inadequate ability to ventilate.
Noninvasive ventilation (NIV)
_____ is a specialized form of NIV used for relatively short treatment periods (approximately __minutes per treatment). The intent of IPPB is not to provide full ventilatory support as with some other forms of NIV but to provide some ______ assisting the patient to deep breathe and stimulating cough.
IPPB, 15, machine-assisted deep breaths
Airways clearance with humidity therapy should be considered in conjunction with IPPB for optimizing results in patients with
______.
retained secretions
Normally, the esophagus does not open until a pressure of about ______ has been reached. _____ represents the greatest risk in patients receiving IPPB at high pressures.
20 to 25 cm H2O, Gastric distention
IPPB therapy best resulting position
semi-Fowlers position
The goal of IPPB therapy is to establish a breathing pattern consisting of about ____ per minute, with an expiratory time of at _______ than inspiration (inspiratory-to-expiratory [I:E] ratio of ≤1:3 to 1:4).
6 breaths, least three to four times longer
There are various ways of determining these volume goals. Most clinical centers strive to achieve an IPPB tidal volume of _________
10 to 15 ml/kg of body weight or at least 30%
of the patient’s predicted IC
PEP and EPAP create _______ only, whereas CPAP maintains a _______throughout both inspiration and expiration
expiratory positive pressure, positive airway pressure
____ elevates and maintains high alveolar and airway pressures throughout the full breathing cycle; this increases ______throughout both inspiration and expiration. Typically, a patient on CPAP breathes through a _______, with pressures maintained between __________. To maintain system pressure throughout the breathing cycle, CPAP requires a source of _____.
CPAP, PL gradient , pressurized circuit against a threshold resistor,5 cm H2O and 20 cm H2O, pressurized gas
The following factors involving PAP, EPAP, and CPAP therapy contribute to the beneficial effects:
(1) recruitment of collapsed alveoli via an increase in FRC,
(2) decreased work of breathing secondary to increased compliance or elimination of intrinsic positive end-expiratory pressure (PEEP),
(3) improved distribution of ventilation through collateral channels (e.g., Kohn pores),
(4) increase in the efficiency of secretion removal.
The corresponding increase in FRC may be lost within _____ after the end of the treatment. For this reason, it has been suggested that CPAP should be used on a continuous basis until the patient recovers.
10 minutes
CPAP by mask also has been used to treat _________. In such patients, CPAP reduces _________, which is helpful in reducing pulmonary vascular congestion. Lung compliance is improved, and the work of breathing is decreased.
cardiogenic pulmonary edema, venous return and cardiac filling pressures
Contraindication of CPAP
hemodynamically unstable, hypoventilation, nausea, facial trauma, untreated pneumothorax, and elevated intracranial pressure (ICP).
Most hazards and complications associated with CPAP are caused by either the ______
increased pressure or the apparatus.
The increased work of breathing caused by the apparatus can lead to ________
hypoventilation and hypercapnia.
The most common problem with PAP therapies is ______
system leaks.
As with IPPB by mask, this potential hazard can be eliminated by use of a _________, although this increases the risk of a leak
nasogastric tube at higher pressure requirements
For a patient having no difficulty with secretions, if the VC exceeds 15 ml/kg of lean body weight or the IC is greater than 33% of predicted, ______ is given.
IS
If either the VC or the IC is less than these threshold levels, IPPB is initiated, with the pressure gradually manipulated from the
initial setting to deliver at least ____
15 ml/kg
If excessive sputum production is a compounding factor, a trial of _____ therapy is substituted for IS. Based on patient response, _______ measures may be added to this regimen.
PEP, bronchodilator therapy and bronchial hygiene
