Ventilation: Noninvasive CPAP and BIPAP – CE

ALERT

Noninvasive positive pressure ventilation (NPPV) should be considered only for patients who are breathing spontaneously.

Leaks and resistance in interface devices may reduce or eliminate the machine’s ability to maintain the set pressure level.

Because of the risk of aspiration, do not restrain patients requiring a face mask on NPPV. The patient should be able to remove the mask in the event of vomiting.

OVERVIEW

NPPV is delivery of ventilatory support without the placement of an artificial airway (an endotracheal tube or tracheostomy); ventilatory support is provided through a nasal mask, nasal pillows, full-face mask, or helmet mask. NPPV is used to prevent airway obstruction during sleep; to maintain or improve ventilation, oxygenation, or both; and to provide respiratory muscle rest in patients in whom invasive mechanical ventilation is not possible, acceptable, or desired.^{undefined#ref2">2} Continuous positive airway pressure (CPAP) is the provision of continuous positive airway pressure throughout inspiration and expiration; bilevel positive airway pressure (BIPAP) is the administration of two levels of airway pressure, one during inspiration and another during expiration.

Modes of NPPV include CPAP and BIPAP:

• CPAP does not provide inspiratory support but maintains positive airway pressure at end-expiration. Collapsed alveoli are recruited, functional residual capacity is increased, ventilation perfusion match is improved, lung compliance is optimized, and the work of breathing is lessened.
• BIPAP provides two levels of pressure, an inspiratory positive airway pressure (IPAP), which may also be referred to as pressure support, and an expiratory positive airway pressure (EPAP). The use of regular intensive-care ventilators permits the addition of intermittent mandatory ventilation. BIPAP is commonly used with acute-care patients.

Indications for NPPV include:

• Obstructive sleep apnea (OSA)
• Acute exacerbation of chronic obstructive pulmonary disease
• Acute cardiogenic pulmonary edema
• Asthma
• Pneumonia
• Postextubation respiratory failure
• Thoracic trauma
• Palliative care and neuromuscular disorders

Absolute contraindications for NPPV include:

• Respiratory arrest, apnea
• Uncontrolled vomiting
• Absence of upper-airway reflexes
• Pneumothorax (untreated)
• Acute, copious upper gastrointestinal bleeding
• Recent gastric, laryngeal, or esophageal surgery
• Facial trauma or airway trauma
• Facial burns
• Total airway obstruction

Relative contraindications for NPPV include:

• Medically unstable—hypotension, cardiac arrhythmias, need for vasopressors
• Agitated or uncooperative
• Excessive secretions
• Impaired swallow reflex
• Cardiac ischemia

An interface is the device that connects the noninvasive ventilator to the patient’s airway.

• Nasal interfaces are the most commonly used in patients with chronic conditions such as OSA. Nasal interfaces include nasal masks (Figure 1) and nasal pillows (Figure 2). Nasal interfaces permit speech and feeding; however, these interfaces are also associated with greater resistance to gas flow and the potential for considerable leakage of gas from the mouth.
• Facial interfaces are the most common in critical care clinical practice and include oronasal masks (Figure 3) and full-face masks (Figure 4). These interfaces vary in size and the area of the face covered and are particularly useful for patients who are mouth breathers. An oronasal mask covers the mouth and nose, whereas a total face mask covers the mouth, nose, and eyes. These interfaces are associated with nasal congestion, skin breakdown, nasal and mouth dryness, and claustrophobia and are less useful in patients who are vomiting. Full- face masks may be better tolerated and induce fewer adverse reactions, but their superiority for outcomes such as mortality has not been demonstrated.

SUPPLIES

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EDUCATION

• Provide developmentally and culturally appropriate education based on the desire for knowledge, readiness to learn, and overall neurologic and psychosocial state.
• Explain the procedure and equipment to the patient and family, including how to remove the mask quickly in the event of vomiting.
• Provide details about the potential sensations associated with NPPV therapy (i.e., dyspnea, claustrophobia, lung inflation).
• Instruct the patient to report immediately any sudden increased difficulty in breathing and any nausea or vomiting.
• Explain to the patient and family that the patient will experience a dry mouth. Instruct the patient to drink fluids, if not contraindicated, and to keep the mouth moist to avoid dehydration from the continuous airflow.
• Teach the patient some relaxation and distraction techniques to facilitate cooperation with NPPV therapy.
• Establish a method of communication in conjunction with the patient and family before initiation of ventilation. Explain that the patient will be able to speak, but that this should be minimized for optimal therapy.
• Encourage questions and answer them as they arise.

ASSESSMENT AND PREPARATION

Assessment

1. Perform hand hygiene before patient contact. Don appropriate personal protective equipment (PPE) based on the patient’s need for isolation precautions or risk of exposure to bodily fluids.
2. Introduce yourself to the patient.
3. Verify the correct patient using two identifiers.
4. Review the patient’s medical history for conditions that predispose the patient to added difficulty with ventilation and oxygenation or for facial trauma, surgery, or malformation that precludes an effective mask seal.
5. Assess the patient’s level of consciousness, level of anxiety, and ability to tolerate the procedure.
6. Assess the patient’s ability to protect the airway with an active gag and cough reflex.
7. Assess the patient’s upper airway patency, including the nasal passages.
8. Assess the patient’s cardiovascular and pulmonary status, including work of breathing.
9. Assess the patient’s vital signs and oxygen saturation.
10. Assess the patient for signs and symptoms of inadequate oxygenation and ventilation, including the presence of visible secretions in the airway, inspiratory wheezes, expiratory crackles, diminished breath sounds, tachypnea, shallow respirations, tachycardia or bradycardia, hypertension or hypotension, and hypoxemia.
11. Assess the patient’s face for pressure points that would place the patient at high risk for pressure injuries.
12. Review the management of clinically appropriate settings for alarms per the organization’s practice.¹

Preparation

1. Review the practitioner’s order for NPPV with the respiratory therapist, including the device settings and the use of humidification and oxygen.
2. Check individual alarm signals for accurate settings, proper operation, and detectability.¹
3. Collaborate with the respiratory therapist regarding the appropriate type of interface, headgear, and NPPV device needed for the prescribed therapy.
4. If the patient is using an NPPV device from home, have the device checked by biomedical engineering per the organization’s practice.
5. Prepare the patient’s face for the interface device. Ensure that the patient’s skin is dry. Apply liquid skin barrier or a hydrocolloid dressing over bony prominences, such as the nose and cheekbones, depending on the type of interface used.

   Rationale: Inappropriate interfaces and headgear reduce the effectiveness of NPPV and may increase complications and decrease compliance. Headgear is needed to stabilize the interface.

6. Set up the suction apparatus.

PROCEDURE

1. Perform hand hygiene and don gloves. Don additional PPE based on the patient’s need for isolation precautions or risk of exposure to bodily fluids.
2. Verify the correct patient using two identifiers.
3. Explain the procedure and ensure that the patient agrees to treatment.
4. Position the patient in an upright position, with the head of the bed elevated 30 degrees.²
5. Assist the respiratory therapist with initiating NPPV as directed.
   1. Hold the interface device on the patient’s face or have the patient hold the interface device until the patient is comfortable with the sensation of NPPV.

      Avoid placing the mask too high over the eyes because doing so can create a leak in the system and can cause eye irritation.

   2. Apply NPPV therapy for short time periods before continuous application of the therapy to give the patient time to become accustomed to the interface device and the therapy.
   3. Set the initial settings at a low level of support. After the patient becomes comfortable with the initial settings, increase the support to the prescribed level as tolerated.
6. Assess the patient’s breathing pattern, including synchrony with the machine.

   Rationale: Assessing patterns of breathing and synchrony with the machine ensures delivery of a set pressure. Adequate support decreases a rapid and shallow breathing pattern and promotes a slower and deeper pattern.

   Report ventilatory asynchrony to the practitioner.

7. Monitor the patient’s work of breathing, oxygen saturation, and vital signs.
8. Monitor the fit of the interface and associated headgear.
   1. Check for leaks around the interface.
   2. Readjust the straps as needed.
   3. Consult with the respiratory therapist if a problem develops.
   4. If air is leaking from the patient’s mouth, use a chin strap with a nasal mask to prevent excessive leaks through the mouth.

      Rationale: An ill-fitting mask affects the delivery of adequate pressure.

9. Remain at the bedside upon initiation of the therapy to coach the patient on how to achieve ventilator synchrony and decrease the anxiety associated with NPPV.
   1. Reassure the patient as needed.
   2. Assess the patient’s response to therapy.
   3. Adjust the ventilator settings as necessary.
10. Set and activate NPPV device alarms, if present.
11. Reassess the patient at least every 30 minutes for tolerance and efficacy of NPPV for the first 1 to 2 hours.²
12. Discard supplies, remove PPE, and perform hand hygiene.
13. Document the procedure in the patient’s record.

MONITORING AND CARE

1. Monitor the patient for changes in oxygenation and ventilation, including vital signs, oxygen saturation, breath sounds, breathing pattern, and work of breathing.

   Reportable conditions: Visible secretions in the airway, inspiratory wheezes, expiratory crackles, diminished breath sounds, increased work of breathing, tachypnea, shallow respirations, tachycardia or bradycardia, hypertension or hypotension, cyanosis.

2. Check for and maintain the proper fit of the patient’s NPPV interface. Readjust the headgear straps as needed.

   Reportable conditions: An ill-fitting interface and leaks around the interface

3. Monitor the patient for gastric insufflations and decompress the stomach as needed.

   Rationale: NPPV can lead to increased gas flow to the stomach. Decompression of the stomach may be necessary.

   Reportable conditions: Gastric distention, nausea, vomiting

4. Suction the patient’s oral and nasal airways as needed.

   Rationale: Increased secretions may impede ventilation.

   Reportable conditions: Increased oral, nasal, or respiratory secretions

5. Frequently assess the patient’s skin in contact with the interface.
   1. Pay close attention to bony prominences of face and head.
   2. Keep the skin clean and dry under the interface.
   3. Use liquid skin barrier or a hydrocolloid dressing under the interface over areas in contact with the interface.
   4. If a pressure injury occurs, assess the appropriateness of the interface. Rotation of the interface device may be required to allow pressure injuries to heal.
   5. Remove the mask every 4 to 6 hours for a few minutes if the patient can tolerate it without increasing respiratory distress.²

      Rationale: Impaired skin integrity increases the risk of infection. The bridge of the nose and the cheeks are prone to skin breakdown.

      Reportable condition: Pressure injury related to interface

6. Assess, treat, and reassess pain.

EXPECTED OUTCOMES

• Improved oxygenation and ventilation
• Reduced work of breathing
• Patient–ventilator synchrony
• Absence of gastric distention
• Ability to clear secretions
• Maintenance of skin integrity
• Adequate pain and anxiety management
• Patient able to cooperate with therapy

UNEXPECTED OUTCOMES

• Aspiration
• Claustrophobia
• Decreased ability to cough and clear secretions
• Discomfort with the interface and related headgear
• Eye irritation
• Gastric insufflation and distention
• Hypercarbia
• Hyperinflation or air trapping
• Hypoxemia
• Inability to obtain adequate nutrition
• Increased or decreased blood pressure
• Increased or decreased heart rate
• Nasal congestion or dryness
• Patient–ventilator asynchrony
• Pneumothorax
• Pressure injuries
• Respiratory muscle fatigue
• Sinus or ear pain

DOCUMENTATION

• Patient’s tolerance of the procedure
• Education
• Type and size of interface
• Date and time therapy is initiated and stopped
• NPPV device settings
• Skin assessment
• Cardiovascular and respiratory assessment
• Vital signs
• Unexpected outcomes and related interventions
• Pain assessment and management

REFERENCES

1. Joint Commission, The. (2022). National Patient Safety Goals for the hospital program. Retrieved October 21, 2022, from https://www.jointcommission.org/-/media/tjc/documents/standards/national-patient-safety-goals/2022/npsg_chapter_hap_jan2022.pdf (Level D)
2. Williams, P.F. (2021). Chapter 50: Noninvasive ventilation. In R.M. Kacmarek, J.K. Stoller, A.J. Heuer (Eds.), Egan’s fundamentals of respiratory care (12th ed., pp. 1105-1127). St. Louis: Elsevier.

Adapted from Wiegand, D.L. (Ed.). (2017). AACN procedure manual for high acuity, progressive, and critical care (7th ed.). St. Louis: Elsevier.

AACN Levels of Evidence

• Level A - Meta-analysis of quantitative studies or metasynthesis of qualitative studies with results that consistently support a specific action, intervention, or treatment
• Level B - Well-designed, controlled studies, with results that consistently support a specific action, intervention, or treatment
• Level C - Qualitative studies, descriptive or correlational studies, integrative reviews, systematic reviews, or randomized controlled trials with inconsistent results
• Level D - Peer-reviewed professional organizational standards with clinical studies to support recommendations
• Level E - Multiple case reports, theory-based evidence from expert opinions, or peer-reviewed professional organizational standards without clinical studies to support recommendations
• Level M - Manufacturer’s recommendations only