Noninvasive Ventilation

Noninvasive ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing (NIV) is an advanced respiratory support that does not require an artificial, invasive airway Airway ABCDE Assessment. This technique is commonly used during acute respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure. The most common forms of NIV are noninvasive positive pressure ventilation Positive pressure ventilation Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator. Flail Chest (NIPPV) and high-flow nasal cannula Nasal Cannula Respiratory Failure (HFNC). In acute respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure, NIV is frequently used to prevent intubation Intubation Peritonsillar Abscess for invasive mechanical ventilation Invasive mechanical ventilation Invasive mechanical ventilation (IMV) is an advanced airway modality used for individuals with immediate or impending respiratory failure and/or in preparation for surgery. The IMV technique involves positive pressure ventilation delivered to the lungs through an endotracheal tube via a ventilator. Invasive Mechanical Ventilation, if there are no contraindications. There are more established contraindications to NIPPV in comparison to HFNC, but NIPPV has demonstrated clear mortality Mortality All deaths reported in a given population. Measures of Health Status benefit in chronic obstructive pulmonary disease Pulmonary disease Diseases involving the respiratory system. Blastomyces/Blastomycosis and congestive heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) exacerbations.

Last updated: 14 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Indications

Definition

Noninvasive ventilation Ventilation The total volume of gas inspired or expired per unit of time, usually measured in liters per minute. Ventilation: Mechanics of Breathing (NIV) is respiratory support that does not require an artificial, invasive airway Airway ABCDE Assessment (such as an endotracheal tube).

Types

  • Noninvasive positive pressure ventilation Positive pressure ventilation Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator. Flail Chest (NIPPV): 
    • Can be provided with: 
    • Typically applied with a sealed face mask that covers both the nose Nose The nose is the human body’s primary organ of smell and functions as part of the upper respiratory system. The nose may be best known for inhaling oxygen and exhaling carbon dioxide, but it also contributes to other important functions, such as tasting. The anatomy of the nose can be divided into the external nose and the nasal cavity. Nose and Nasal Cavity: Anatomy and the mouth. 
    • Can also be used in the form of a helmet
    • Positive airway Airway ABCDE Assessment pressure allows alveolar recruitment Recruitment Skeletal Muscle Contraction to participate in oxygenation. 
  • High-flow nasal cannula Nasal Cannula Respiratory Failure (HFNC):
    • Another form of NIV that uses high concentrations of oxygen, which may be delivered at up to 60 L/min via large-bore nasal cannula Nasal Cannula Respiratory Failure
    • At higher flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure rates, HFNC generates positive end-expiratory pressure Positive end-expiratory pressure Pressure remaining in the distal airways of the patient at the end of expiration Invasive Mechanical Ventilation ( PEEP PEEP Pressure remaining in the distal airways of the patient at the end of expiration Invasive Mechanical Ventilation) above the physiologic level.

Indications

The most common indication for use is acute respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure:

Common conditions that may be suitable for NIV:

  • Acute hypoxic respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure
    • Infection/ pneumonia Pneumonia Pneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy. Pneumonia
    • Asthma Asthma Asthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma exacerbation
    • Pulmonary embolism Pulmonary Embolism Pulmonary embolism (PE) is a potentially fatal condition that occurs as a result of intraluminal obstruction of the main pulmonary artery or its branches. The causative factors include thrombi, air, amniotic fluid, and fat. In PE, gas exchange is impaired due to the decreased return of deoxygenated blood to the lungs. Pulmonary Embolism
    • Atelectasis Atelectasis Atelectasis is the partial or complete collapse of a part of the lung. Atelectasis is almost always a secondary phenomenon from conditions causing bronchial obstruction, external compression, surfactant deficiency, or scarring. Atelectasis
    • Posttrauma
  • Acute hypercapnic respiratory failure Hypercapnic Respiratory Failure Respiratory Failure +/– acute hypoxic respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure:
    • Asthma Asthma Asthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma or chronic obstructive pulmonary disease Pulmonary disease Diseases involving the respiratory system. Blastomyces/Blastomycosis ( COPD COPD Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD)) exacerbation
    • Congestive heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR) ( CHF CHF Congestive heart failure refers to the inability of the heart to supply the body with normal cardiac output to meet metabolic needs. Echocardiography can confirm the diagnosis and give information about the ejection fraction. Congestive Heart Failure) exacerbation/ pulmonary edema Pulmonary edema Pulmonary edema is a condition caused by excess fluid within the lung parenchyma and alveoli as a consequence of a disease process. Based on etiology, pulmonary edema is classified as cardiogenic or noncardiogenic. Patients may present with progressive dyspnea, orthopnea, cough, or respiratory failure. Pulmonary Edema
    • Hypoventilation from sedation
    • Progressive obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity hypoventilation syndrome
    • Progressive neuromuscular disorder
  • Note: Studies have shown a mortality Mortality All deaths reported in a given population. Measures of Health Status benefit of NIPPV in COPD COPD Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by progressive, largely irreversible airflow obstruction. The condition usually presents in middle-aged or elderly persons with a history of cigarette smoking. Signs and symptoms include prolonged expiration, wheezing, diminished breath sounds, progressive dyspnea, and chronic cough. Chronic Obstructive Pulmonary Disease (COPD) and CHF CHF Congestive heart failure refers to the inability of the heart to supply the body with normal cardiac output to meet metabolic needs. Echocardiography can confirm the diagnosis and give information about the ejection fraction. Congestive Heart Failure exacerbations.

Contraindications

While NIV may reduce the need for invasive mechanical ventilation Invasive mechanical ventilation Invasive mechanical ventilation (IMV) is an advanced airway modality used for individuals with immediate or impending respiratory failure and/or in preparation for surgery. The IMV technique involves positive pressure ventilation delivered to the lungs through an endotracheal tube via a ventilator. Invasive Mechanical Ventilation and its associated complications, careful consideration for patient selection Selection Lymphocyte activation by a specific antigen thus triggering clonal expansion of lymphocytes already capable of mounting an immune response to the antigen. B cells: Types and Functions is essential to prevent harm. 

Common contraindications for NIPPV include:

Contraindications for HFNC:

  • There are no clear absolute contraindications at this time, as few studies are available.
  • Potential contraindications include:

Noninvasive Positive Pressure Ventilation

Basic settings controlled by the operator

Background physiology

High-Flow Nasal Cannula

Basic settings controlled by the operator

There are 2 parameters that affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment oxygenation:

  • Flow rate Flow rate maximum flow the ventilator will deliver a set tidal volume in liters per minute Invasive Mechanical Ventilation (generally optimized first to avoid FiO2 levels > 60%, when possible)
  • FiO2

Background physiology

  • HFNC delivers heated and humidified oxygen for the following physiologic effects:
    • Washes out CO2 from the anatomical dead space Dead space That part of the respiratory tract or the air within the respiratory tract that does not exchange oxygen and carbon dioxide with pulmonary capillary blood. Ventilation: Mechanics of Breathing
    • Can generate a moderate level of PEEP PEEP Pressure remaining in the distal airways of the patient at the end of expiration Invasive Mechanical Ventilation → ↑ recruitment Recruitment Skeletal Muscle Contraction of collapsed alveoli Alveoli Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place. Acute Respiratory Distress Syndrome (ARDS) 
    • Improved comfort (improves compliance Compliance Distensibility measure of a chamber such as the lungs (lung compliance) or bladder. Compliance is expressed as a change in volume per unit change in pressure. Veins: Histology) through: 
      • Humidification and warming of oxygen 
      • No mask
    • May have fewer hemodynamic effects than NIPPV
    • Can ↓ work of breathing Work of breathing Respiratory muscle contraction during inhalation. The work is accomplished in three phases: lung compliance work, that required to expand the lungs against its elastic forces; tissue resistance work, that required to overcome the viscosity of the lung and chest wall structures; and airway resistance work, that required to overcome airway resistance during the movement of air into the lungs. Work of breathing does not refer to expiration, which is entirely a passive process caused by elastic recoil of the lung and chest cage. Pulmonary Examination
  • Best used in acute hypoxic respiratory failure Respiratory failure Respiratory failure is a syndrome that develops when the respiratory system is unable to maintain oxygenation and/or ventilation. Respiratory failure may be acute or chronic and is classified as hypoxemic, hypercapnic, or a combination of the two. Respiratory Failure:

Complications

The most feared complication for NIV is delaying a potentially lifesaving intervention because of poor patient selection Selection Lymphocyte activation by a specific antigen thus triggering clonal expansion of lymphocytes already capable of mounting an immune response to the antigen. B cells: Types and Functions

Major complications for noninvasive positive pressure ventilation Positive pressure ventilation Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator. Flail Chest

Major complication for high-flow nasal cannula Nasal Cannula Respiratory Failure

Weaning

Timing

There are no set guidelines on how to specifically wean, but can be considered when on minimal NIV settings:

  • Minimal BiPap settings are considered: 
    • IPAP, ≤ 10 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg 
    • PEEP PEEP Pressure remaining in the distal airways of the patient at the end of expiration Invasive Mechanical Ventilation, 5 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg
    • FiO2, ≤ 40%, with good oxygen saturations
    • Settings can be variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables and depend on comorbidities Comorbidities The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival. St. Louis Encephalitis Virus.
  • Minimal HFNC settings are considered: 
    • Flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure, ≤ 20 L/min 
    • FiO2, ≤ 40%

Considerations before weaning Weaning Techniques for effecting the transition of the respiratory-failure patient from mechanical ventilation to spontaneous ventilation, while meeting the criteria that tidal volume be above a given threshold (greater than 5 ml/kg), respiratory frequency be below a given count (less than 30 breaths/min), and oxygen partial pressure be above a given threshold (pao2 greater than 50mm hg). Weaning studies focus on finding methods to monitor and predict the outcome of mechanical ventilator weaning as well as finding ventilatory support techniques which will facilitate successful weaning. Present methods include intermittent mandatory ventilation, intermittent positive pressure ventilation, and mandatory minute volume ventilation. Invasive Mechanical Ventilation

  • Was the underlying reason for use addressed, and is it resolving?
  • Has severe tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination resolved?
  • Is the individual on minimal NIV settings?
  • Is the SpO2 > 88%–92% or the PaO2 > 55‒60 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg?
  • Has the individual’s mental status improved?

Weaning Weaning Techniques for effecting the transition of the respiratory-failure patient from mechanical ventilation to spontaneous ventilation, while meeting the criteria that tidal volume be above a given threshold (greater than 5 ml/kg), respiratory frequency be below a given count (less than 30 breaths/min), and oxygen partial pressure be above a given threshold (pao2 greater than 50mm hg). Weaning studies focus on finding methods to monitor and predict the outcome of mechanical ventilator weaning as well as finding ventilatory support techniques which will facilitate successful weaning. Present methods include intermittent mandatory ventilation, intermittent positive pressure ventilation, and mandatory minute volume ventilation. Invasive Mechanical Ventilation trial

Once weaned to minimal settings, a weaning Weaning Techniques for effecting the transition of the respiratory-failure patient from mechanical ventilation to spontaneous ventilation, while meeting the criteria that tidal volume be above a given threshold (greater than 5 ml/kg), respiratory frequency be below a given count (less than 30 breaths/min), and oxygen partial pressure be above a given threshold (pao2 greater than 50mm hg). Weaning studies focus on finding methods to monitor and predict the outcome of mechanical ventilator weaning as well as finding ventilatory support techniques which will facilitate successful weaning. Present methods include intermittent mandatory ventilation, intermittent positive pressure ventilation, and mandatory minute volume ventilation. Invasive Mechanical Ventilation trial can be attempted:

  • Remove individual from NIV and use nasal cannula Nasal Cannula Respiratory Failure and closely monitor for deterioration.
  • Individuals may be trailed off for about an hour → reassess respiratory status frequently thereafter

References

  1. Luecke, T., Pelosi, P. (2005). Clinical review: positive end-expiratory pressure and cardiac output. Critical Care 9:607. https://doi.org/10.1186/cc3877
  2. Nickson, C. (2019, September 14). Non-invasive ventilation (NIV). Life in the Fast Lane. https://litfl.com/non-invasive-ventilation-niv/
  3. Nishimura, M. (2015). High-flow nasal cannula oxygen therapy in adults. J Intens Care 3(1):15. https://doi.org/10.1186/s40560-015-0084-5
  4. Hackett, A.J. (2018). Non-Invasive ventilation in Critical CARE: Positive pressure ventilation AND High-flow oxygen therapy. PulmCCM. Retrieved December 12, 2021, from https://pulmccm.org/critical-care-review/non-invasive-ventilation-in-critical-care-positive-pressure-ventilation-and-high-flow-oxygen-therapy/
  5. Soo Hoo, G.W. (2020). Noninvasive ventilation. Medscape. Retrieved December 12, 2021, from https://emedicine.medscape.com/article/304235-overview#a1
  6. Hyzy, R.C. (2021). Heated and humidified high-flow nasal oxygen in adults: practical considerations and potential applications. UpToDate. Retrieved December 12, 2021, from https://www.uptodate.com/contents/heated-and-humidified-high-flow-nasal-oxygen-in-adults-practical-considerations-and-potential-applications#H1033389248
  7. Hyzy, R.C., McSparron, J.I. (2021). Noninvasive ventilation in adults with acute respiratory failure: benefits and contraindications. UpToDate. Retrieved December 12, 2021, from https://www.uptodate.com/contents/noninvasive-ventilation-in-adults-with-acute-respiratory-failure-benefits-and-contraindications
  8. Pinto, V.L., Sharma, S. (2021). Continuous positive airway pressure. StatPearls. Retrieved December 12, 2021, from https://www.ncbi.nlm.nih.gov/books/NBK482178/

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