Mechanical Ventilation (Neonatal) - CE/NCPD

The content in Clinical Skills is evidence based and intended to be a guide to clinical practice. Always follow your organization’s practice.

ALERT

Mechanical ventilation may contribute to an acute or a chronic respiratory tract injury, such as atelectrauma, volutrauma, barotrauma, oxygen toxicity, and a pulmonary or systemic inflammatory response to lung trauma.^{undefined#ref2">2}

OVERVIEW

Mechanical ventilation is respiratory support using mechanical assistance.³ The goals of mechanical ventilation are to facilitate adequate gas exchange and decrease the neonate’s work of breathing, while minimizing the risk of lung injury and optimizing comfort.⁴

Neonatal respiratory support is an ever-evolving field. The increased use of improved noninvasive respiratory modalities, which are generally accepted as the preferred modes of support, can reduce the need for invasive mechanical ventilation. Indications for mechanical ventilation are respiratory failure, pulmonary insufficiency, severe apnea and bradycardia, congenital cardiac disease, central nervous system disease, and surgery.

Neonates present unique challenges that complicate the use of mechanical ventilation, including noncompliant lungs; rapid, irregular respiratory rates; short inspiratory times; and limited muscle strength. In addition, the approach to respiratory support and treatment differs based on gestational age.⁴

In positive pressure ventilation, a breath is delivered until a specific pressure or volume is reached. There are four main categories of how pressure or volume of air is delivered:

• Pressure-cycled ventilation
  • Air is delivered to the patient until a preset pressure is achieved.
  • Inspiratory time ends when the preset pressure is delivered.
  • The volume required to deliver the preset pressure is variable with each breath.
• Time-cycled, pressure-limited, continuous flow ventilation
  • This type of ventilation is similar to pressure-cycled ventilation except that the predetermined pressure is delivered during a set inspiration time.
• Pressure support ventilation
  • The ventilator supports breaths initiated by the patient.
  • The ventilator delivers mechanical breaths to a preset volume.
  • Variable inspiratory time allows the patient to achieve synchrony with the ventilator.
  • In many cases, the ventilator is used as a weaning mode of ventilation.
• Volume-cycled ventilation
  • A preset volume is delivered to the patient.
  • Inspiratory time ends when the preset volume is delivered.
  • The pressure required to deliver the preset volume is variable with each breath.

Positive pressure ventilation measuring volume delivers more stable tidal volume (VT) (Table 1) and allows the ventilator to adjust to the patient’s lung compliance over time.⁵ Volume ventilation has the advantage of automatically reducing inflation pressure when lung compliance improves because the underlying pulmonary condition resolves. Volume ventilation as compared to pressure ventilation is associated with a significant reduction in the incidence of pneumothorax, hypocarbia, intraventricular hemorrhage, periventricular leukomalacia, and the duration of mechanical ventilation.³

There are two modes for how ventilation rates are determined: intermittent mandatory ventilation and patient-triggered ventilation. For patient-triggered ventilation, there are five options available.³

• Intermittent mandatory ventilation: Ventilator breaths are delivered at a predetermined rate and not synchronized with the patient’s breath.
• Patient-triggered ventilation: Ventilator breaths are delivered in response to a signal from the patient and synchronized with spontaneous breaths. The five types of patient-triggered ventilation are:
  • Synchronized intermittent mandatory ventilation
  • Assist control (AC) mode of ventilation
  • Pressure support ventilation
  • Volume-targeted ventilation
  • Neurally adjusted ventilatory assist

These various modes of mechanical ventilation are best classified based on how each breath is initiated, how the gas flow controls each breath, and how the breath ends (Table 2).

In addition to these modes of mechanical ventilation, there are high-frequency ventilation (HFV) modes, which use small VT at rapid rates. The most common forms of HFV used in the neonate are high-frequency oscillatory ventilation (HFOV) and high-frequency jet ventilation (HFJV).^2,3 The advantage of HFV modes over other modes of mechanical ventilation is the ability to deliver adequate volumes with decreased airway pressure.

Indications for the use of HFV include severe lung disease that is unresponsive to other forms of mechanical ventilation, pulmonary air leaks, and pulmonary hypoplasia. Both HFOV and HFJV deliver gentle ventilation and are very effective with disorders in which carbon dioxide elimination is the major problem. Severe atelectatic disorders (e.g., respiratory distress syndrome) and obstructive disorders (e.g., meconium aspiration syndrome) have been shown to respond to HFJV.^2,3 Determining the appropriate ventilator mode is based on the individual patient’s condition, disease process, and response to previous ventilatory support (Table 3).

Ensuring the proper placement of the endotracheal (ET) tube is essential during mechanical ventilation. Monitoring exhaled carbon dioxide levels helps determine if the ET tube is in the correct place. End-tidal and side-stream carbon dioxide monitors are available to assess the levels of exhaled carbon dioxide effectively. Failure to detect exhaled carbon dioxide in patients with adequate cardiac output strongly suggests esophageal intubation.

Because neonates have a limited volume of exhaled gas, in some cases several breaths must be passed through the sensor to detect carbon dioxide. Sometimes poor or absent pulmonary blood flow (e.g., during cardiac arrest) may result in failure to detect exhaled carbon dioxide despite correct tube placement in the trachea. Failure to detect carbon dioxide can lead to the conclusion that the tube is incorrectly placed and thus results in unnecessary extubation and reintubation in these critically ill neonates.¹

The use of an uncuffed ET tube is preferred in neonates to prevent airway necrosis; however, this type of ET tube is less secure, and unplanned extubations can occur with minimal tube movement. Signs of extubation include sudden deterioration in clinical status, abdominal distention, crying, decreased chest wall movement, breath sounds in the abdomen, agitation, cyanosis, and bradycardia.

SUPPLIES

See Supplies tab at the top of the page.

FAMILY EDUCATION

• Provide developmentally and culturally appropriate education based on the desire for knowledge, readiness to learn, and overall neurologic and psychosocial state.
• Explain the purpose for and complications of mechanical ventilation.
• Provide the family with descriptions and explanations of the equipment and alarms.
• Discuss the need for suctioning and explain the procedure to the family.
• Discuss methods the family may use to interact with and calm the neonate.
• 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 the risk of exposure to bodily fluids.
2. Introduce yourself to the family.
3. Verify the correct patient using two identifiers.
4. Ensure that a manual ventilation bag (MVB), mask, and suction are immediately available and connected at the patient’s bedside.

   Rationale: Emergency equipment is necessary for sudden changes in the patient’s condition or in the event of ventilator failure.³

5. Assess the family’s understanding of the reasons for and the risks and benefits of the procedure.

Preparation

1. Inspect the ventilator equipment and settings.
   1. Parameters to review when using conventional ventilation include fraction of inspired oxygen (FIO₂), ventilator rate, positive inspiratory pressure (PIP), positive end-expiratory pressure (PEEP), VT, inspiration-to-expiration ratio (I:E ratio), flow rate, and mean airway pressure (MAP).
   2. Parameters to review when using HFV include FIO₂, amplitude, frequency, and MAP.
2. Assess the ventilator alarm status.

PROCEDURE

1. Perform hand hygiene and don gloves. Don additional PPE based on the patient’s need for isolation precautions or the risk of exposure to bodily fluids.
2. Verify the correct patient using two identifiers.
3. Explain the procedure to the family and ensure that they agree to treatment.
4. Administer the prescribed sedatives and pain medications and reassess the patient’s pain status regularly.

   Rationale: Early identification of the patient’s comfort level allows immediate attention to problems. Sedation may be necessary to achieve ventilator synchrony but should be used with caution.⁷

5. Assess the patient’s vital signs and cardiopulmonary stability, including spontaneous respiratory rate, chest expansion (in conventional ventilation) or vibration (in HFV), and response to mechanical ventilator cycling.
6. Auscultate the patient’s breath sounds, including upper and lower lung fields and differences in left and right lung fields. Include the equality of aeration and the presence of crackles or other abnormal lung sounds.
7. Assess chest wall vibration when using HFV.

   Rationale: Chest wall vibration is an indicator of lung compliance, airway patency, and effectiveness of ventilator settings. An increase in chest wall vibration accompanied by an increase in partial pressure of arterial oxygen (PaO₂) and a decrease in arterial partial pressure of carbon dioxide (PaCO₂) is an indication to consider weaning the ventilator settings. A sudden decrease in chest wall vibration may indicate a plugged or displaced ET tube or a pneumothorax. Unless ventilation is stopped, assessing the patient’s breath sounds during HFV is impossible.³

8. Assess ET tube stability and centimeter marking at the gumline once per shift and as needed.
9. Assess the patient for signs of ventilatory failure, including increased PaCO₂, decreased arterial oxygen saturation (SaO₂), increased work of breathing, tachypnea, and increased retractions.
10. Assess the patient for signs of hypoxemia, including decreased SaO₂, pale or cyanotic color, tachycardia or bradycardia, tachypnea, agitation, increased work of breathing, increased retractions, and acidosis.
11. Assess radiographic findings, blood gas analysis, and the patient’s clinical status for indications that weaning from the ventilator can be initiated.
12. Ensure that the head of the bed is slightly elevated, unless contraindicated.

    Rationale: Elevating the head of the bed reduces the incidence of aspiration and is a recommended practice in the prevention of ventilator-associated pneumonia.⁶

13. Assess the need for suctioning. Signs that may indicate a need for suctioning include:
    1. Visible secretions in the ET tube
    2. Coarse or decreased breath sounds
    3. Changes in vital signs
    4. Decreased oxygen saturation
    5. Increased partial pressure of transcutaneous carbon dioxide (PtCCO₂) readings
    6. Decreased chest wall movement
    7. Decreased chest wall vibration for patients on HFV
14. Suction as needed.

    Suctioning is not a benign procedure. Suction only as needed to maintain airway patency and remove secretions. Carefully assess the patient’s conditions that require ET tube suctioning.

    1. Suction the ET tube using the shallow or measured technique, preferably with a closed, inline suction device.
    2. Notice and document the characteristics of secretions.
15. Respond immediately to ventilator alarms and watch for changes and fluctuations in prescribed settings, which may indicate water in the tubing or the need for suctioning.

    Rationale: An alarm may be associated with the need for suctioning or the need to drain water from the tubing, or it may indicate that the ventilator tubing has been disconnected.

    Report to the practitioner any inappropriate sounding of alarms.

16. Adjust ventilator settings (as ordered) in collaboration with the practitioner and respiratory therapist on the basis of treatment strategies and the patient’s response. Wean the patient from the ventilator as soon as possible to minimize lung injury.

    Rationale: Changes in lung compliance may occur, resulting in the need for more or less ventilator support.³

17. Discard supplies, remove PPE, and perform hand hygiene.
18. Document the procedure in the patient’s record.

MONITORING AND CARE

1. Review the ventilator settings at the beginning of each shift and with every vital sign assessment.
2. At the beginning of each shift, confirm that all alarms are activated.
3. Auscultate breath sounds and monitor chest excursion, spontaneous effort, air entry, and the patient’s color as the condition warrants. Monitor chest vibrations when the patient is undergoing HFV.
4. Suction as indicated, preferably using a closed, inline suctioning method.

   Rationale: Closed, inline suctioning devices allow suctioning while ventilation continues, which minimizes the fluctuations in oxygenation, changes in cerebral blood flow, and other hemodynamic changes. Closed, inline suctioning also decreases the risk of infection by decreasing the potential for contamination of the ET tube and suction catheter.

5. Monitor signs of changes in oxygenation and ventilation, including lung sounds and aeration of lung segments, vital signs, oxygen saturation, PtCCO₂ and partial pressure of transcutaneous oxygen (PtCO₂) as appropriate, arterial or capillary blood gases, cyanosis, work of breathing, adequacy of chest excursion, and chest radiography findings.
6. Monitor and document SaO₂ values as needed or more frequently if warranted.
7. Monitor and document PtCCO₂ and PtCO₂ values (when applicable) as ordered or as the patient’s condition warrants.
8. Monitor and document site changes and correlate values with blood gases as indicated. Change the site and calibrate the electrode based on the manufacturer’s calibration directions and the organization’s practice, and as the patient’s condition warrants.
9. Monitor blood gases as indicated, typically after initiation of assisted ventilation, after significant changes in ventilation settings, and with changes in the patient’s condition.
10. Monitor gastric insufflations and remove air from the stomach as indicated.
11. Provide oral care as needed when performing hands-on care.
12. Monitor for signs of unplanned extubation, including the sudden deterioration in clinical status, decreased oxygen saturation or PtCO₂ readings, abdominal distention, crying, decreased chest wall movement, breath sounds in the abdomen, agitation, cyanosis, or bradycardia.
13. Assess, treat, and reassess pain.

EXPECTED OUTCOMES

• Adequate oxygenation and ventilation
• Oxygenation and ventilation without lung injury
• Hemodynamic stability
• Proper placement of ET tube
• Absence of infection
• Mobilization and removal of secretions
• Discontinuation of mechanical ventilation as soon as patient is physiologically ready
• Adequate management of pain and agitation for patient

UNEXPECTED OUTCOMES

• Inadequate ventilation or oxygenation (e.g., hypoxemia, hypercarbia, acidosis, alkalosis)
• Lung overinflation
• Air-leak syndrome
• Acute lung injury: barotrauma, volutrauma, or progression of lung disease
• Atelectasis
• Hemodynamic instability
• Unplanned extubation or malposition of ET tube
• Ventilator-associated pneumonia
• ET tube obstruction
• Inadequately managed pain and agitation due to presence of ET tube or hypoxemia

DOCUMENTATION

• Cardiopulmonary assessment, including vital signs, lung sounds, work of breathing, chest excursion and symmetry if the patient is on conventional ventilation, chest vibration if the patient is on HFV, capillary or arterial blood gases, pulse oximetry, and PtCCO₂ and PtCO₂
• Date, time, and response to the initiation of ventilator assistance
• Conventional ventilator settings, if appropriate, including FIO₂, mode, VT, intermittent mandatory ventilation, PIP, ventilator rate, and PEEP
• HFV settings, if appropriate, including FIO₂, amplitude, frequency, and MAP
• Timing of suctioning, characteristics of ET tube secretions, patient’s response to suctioning, and assessment of breath sounds after suctioning
• Additional interventions and patient’s response
• Comfort assessment
• Education
• Unexpected outcomes and related interventions

REFERENCES

1. Aziz, K. and others. (2020). Part 5: Neonatal resuscitation: 2020 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation, 142(16 Suppl. 2), S524-S550. doi:10.1161/CIR.0000000000000902 Retrieved June 25, 2024, from https://www.ahajournals.org/doi/10.1161/CIR.0000000000000902
2. Carpi, M.F. (2017). High-frequency jet ventilation in preterm infants: Is there still room for it? Respiratory Care, 62(7), 997-998. doi:10.4187/respcare.05647
3. Fraser, D., Diehl-Jones, W. (2021). Chapter 26: Assisted ventilation. In M.T. Verklan, M. Walden, S. Forest (Eds.), Core curriculum for neonatal intensive care nursing (6th ed., pp. 425-445). St. Louis: Elsevier.
4. Gardner, S.L., Enzman-Hines, M., Nyp, M. (2021). Chapter 23: Respiratory diseases. In S.L. Gardner and others (Eds.) Merenstein & Gardner's handbook of neonatal intensive care: An interprofessional approach (9th ed., pp. 729-835). St. Louis: Elsevier.
5. Kacmarek, R.M. (2021). Chapter 53: Discontinuing ventilatory support. In R.M. Kacmarek, J.K. Stoller, A.J. Heuer (Eds.), Egan’s fundamentals of respiratory care (12th ed., pp. 1184-1211). St. Louis: Elsevier.
6. Smith, J.R., Donze, A. (2021). Chapter 18: Patient safety. In M.T. Verklan, M. Walden, S. Forest (Eds.), Core curriculum for neonatal intensive care nursing (6th ed., pp. 301-328). St. Louis: Elsevier.
7. Zimmerman, K.O. and others. (2017). Sedation, analgesia, and paralysis during mechanical ventilation of premature infants. The Journal of Pediatrics, 180, 99-104. doi:10.1016/j.jpeds.2016.07.001

Clinical Review: Justin J. Milici, MSN, RN, CEN, CPEN, CPN, TCRN, CCRN, FAEN

Published: August 2024