Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Patient selection and alternative modes of ventilatory support

INTRODUCTION — Noninvasive ventilation (NIV) refers to ventilation without an invasive device (eg, tracheostomy or endotracheal tube). The noninvasive device connects the patient's airway to the ventilator. In contrast with invasive ventilation, NIV uses an open breathing circuit, is inherently leaky, and depends upon patient cooperation to achieve ventilatory assistance. Patients with chronic respiratory failure due to respiratory muscle weakness from underlying neuromuscular or chest wall diseases frequently require positive pressure NIV. Alternative modes of ventilatory support are also available but are limited in their application.

This topic discusses patient selection for positive pressure NIV and alternative modes of ventilatory support in patients with chronic respiratory failure due to neuromuscular and chest wall diseases (table 1). The initial application of and adaptation to NIV in patients with chronic respiratory failure due to neuromuscular and chest wall disease and the application of positive pressure NIV in patients with acute respiratory failure are described separately.

●(See "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Practical aspects of initiation".)

●(See "Noninvasive ventilation in adults with acute respiratory failure: Benefits and contraindications".)

●(See "Noninvasive ventilation in adults with acute respiratory failure: Practical aspects of initiation".)

●(See "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Adaptation and follow-up after initiation".)

POSITIVE PRESSURE NONINVASIVE VENTILATION — In patients with chronic respiratory failure from respiratory muscle weakness due to neuromuscular and chest wall disorders, positive pressure NIV is the preferred mode of ventilation. Positive pressure NIV has largely supplanted negative pressure NIV and other modes of ventilation due to its portability and ease of use (table 1). (See 'Other options' below.)

The potential benefits of chronic NIV support include improvements in daytime gas exchange, sleep, quality of life, and in some cases, survival. Data that support the efficacy of NIV in this population are discussed separately. (See "Respiratory muscle weakness due to neuromuscular disease: Management".)

Patient selection

Indications — A number of neuromuscular and chest wall diseases may lead to chronic respiratory failure (table 2). Despite the diversity of the mechanisms associated with chronic respiratory failure in these conditions, the indications for and application of NIV are generally similar. In this population, subjective clinical findings and objective physiologic tests are used to determine when NIV is indicated (table 3) [1,2].

●Symptomatic chronic respiratory failure with evidence of nocturnal and/or daytime hypoventilation is the most common indication for chronic ventilatory assistance. (See "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Symptomatic chronic respiratory failure'.)

●In patients with progressive neuromuscular disorders (eg, amyotrophic lateral sclerosis), early physiologic evidence of respiratory muscle weakness often prompts assessment for initiation of NIV. (See "Symptom-based management of amyotrophic lateral sclerosis", section on 'Respiratory function management'.)

●In patients with neuromuscular and chest wall disease, symptoms suggestive of sleep-disordered breathing (such as obstructive sleep apnea) may prompt evaluation for nocturnal NIV in the sleep laboratory with polysomnography [3]. However, polysomnography is not necessary in the absence of symptoms suggestive of an underlying sleep disorder. (See "Evaluation of sleep-disordered breathing in adult patients with neuromuscular and chest wall disorders" and "Clinical presentation and diagnosis of obstructive sleep apnea in adults", section on 'Diagnostic evaluation'.)

Contraindications — Most contraindications for chronic NIV use are relative but include severe facial deformities that limit the application of an NIV interface (although custom-built masks may be available) and inability to protect the upper airway (eg, significant upper airway/bulbar dysfunction, poor mental status, severely weakened cough, and inability to clear secretions) (table 4).

Patient preferences — In all patients in whom chronic NIV is being considered, we thoroughly discuss the advantages and disadvantages of NIV and its efficacy in terms of improved survival and quality of life.

Importantly, among the etiologies, chronic respiratory failure may have variable degrees of reversibility, a feature that requires clarity when discussing the pros and cons of NIV and duration of NIV use with patients and their caregivers. This includes diseases that are:

●Completely or partially reversible with or without treatment (eg, Guillain-Barré syndrome, myasthenia gravis)

●Relapsing and remitting (eg, multiple sclerosis)

●Relentlessly progressive (eg, amyotrophic lateral sclerosis)

As examples:

●For patients with progressive neuromuscular disease (eg, amyotrophic lateral sclerosis), it should be made clear that NIV is not a cure, but rather, is a palliative therapy that delays the need for invasive mechanical ventilation (ie, a tracheostomy). (See "Symptom-based management of amyotrophic lateral sclerosis", section on 'Noninvasive positive pressure ventilation'.)

●In contrast, for patients with stable neuromuscular disorders, many patients may remain on NIV lifelong and have an acceptable quality of life (eg, spinal cord trauma). (See "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Adaptation and follow-up after initiation" and "Respiratory muscle weakness due to neuromuscular disease: Management".)

Discussing other options at this point is also reasonable, although it should be made clear that NIV is the preferred method of supporting chronic respiratory failure in patients with neuromuscular or chest wall disorders. Other options include the following:

●Invasive mechanical ventilation with tracheostomy. (See 'Tracheostomy with positive pressure ventilation' below and "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Tracheostomy'.)

●Potential eligibility for diaphragmatic pacing. (See "Pacing the diaphragm: Patient selection, evaluation, implantation, and complications", section on 'Selection of potential candidates'.)

●Continued conservative medical and supportive therapy without NIV support. (See 'Others (declining or rare use)' below and 'Adjunctive therapy (cough supplementation, nutrition)' below and "Assessment and management of dyspnea in palliative care".)

In most cases, patients choose positive pressure NIV since it enables them to maintain a good quality of life for prolonged periods. This includes travel, talking, and eating (which are more challenging with tracheostomy). NIV carries less risk and is less labor intensive than tracheostomy. In addition, NIV as a ventilatory mode is likely as efficacious as tracheostomy and devices are more portable than tracheostomy. In addition, NIV avoids all the complications of tracheostomy (bleeding, tracheal stenosis, recurrent lung infection, tracheomalacia). (See "Tracheostomy in adults: Techniques and intraoperative complications", section on 'Intraoperative complications' and "Tracheostomy: Postoperative care, maintenance, and complications in adults", section on 'Complications'.)

The need for adequate caregiver support and training is important when NIV is being considered since support is needed for success. It is also important to emphasize that chronic NIV use may have a psychological impact on caregivers [4,5]. As patients survive longer with NIV, caregiver stress appears to increase due to a greater burden of progressive illness that may also include additional comorbidities such as aspiration and parenteral tube feeding.

Initiation and adaptation — NIV initiation involves selecting an appropriate interface (ie, a mask or other device that directs airflow into the upper airway (picture 1 and picture 2)) and ventilator device (typically a positive pressure ventilator (picture 3)). The patient then undergoes an initial trial, the purpose of which is to perform initial titration of NIV settings and allow the patient to become comfortable with NIV. Further details regarding the practical aspects of application are provided separately. (See "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Practical aspects of initiation".)

Following the initial trial, patients undergo further adaptation and titration for optimization of settings in the subsequent few weeks. Efforts should be made to encourage compliance and address reasons for nonadherence. These issues and the role of telemonitoring are discussed separately. (See "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Adaptation and follow-up after initiation" and "Assessing and managing nonadherence with continuous positive airway pressure (CPAP) for adults with obstructive sleep apnea", section on 'Electronic resources (telehealth, telemonitoring, active patient engagement)'.)

The level of support needed is influenced by the underlying indication and disease reversibility.

Chronic long-term use — Following adaptation, some patients are maintained on nocturnal NIV, while others require full-time or near full-time ventilation during the day and night (ie, continuous noninvasive ventilatory support [CNVS]). The rate of progression and nature of the circumstances underlying neuromuscular disease determine whether and how rapidly patients transition from nocturnal NIV to CNVS. Aspects of the chronic care of patients on CNVS, including supportive measures and transitioning between invasive and noninvasive ventilation, are described separately. (See "Noninvasive ventilatory support and mechanical insufflation-exsufflation for patients with respiratory muscle dysfunction".)

Weaning — For patients with reversible disease (eg, Guillain-Barré syndrome, myasthenia gravis crisis), settings may be lowered on an as-tolerated basis by slowly reducing the level and duration of support. This process generally takes weeks to months, and nocturnal support is typically weaned last.

There is no set protocol for weaning NIV, but we generally use symptoms and occasionally measure serum bicarbonate and, rarely, arterial blood gas analysis to ensure normal ventilation before discontinuation. Spirometry is not typically used.

OTHER OPTIONS — Other modes of ventilatory support are limited in their application. These include tracheostomy and diaphragmatic pacing. (See 'Tracheostomy with positive pressure ventilation' below and 'Diaphragm pacers' below.)

While negative pressure ventilation, abdominal respirators, and glossopharyngeal breathing (GPB) were used more widely in the past, they have been replaced by positive pressure NIV. (See 'Others (declining or rare use)' below.)

Other than tracheostomy and negative pressure ventilators, most of these options are targeted at reducing time spent on or delaying the need for mechanical ventilation.

Tracheostomy with positive pressure ventilation — Tracheostomy with positive pressure ventilation is best suited to patients who have an inability to tolerate NIV or patients with contraindications to NIV (eg, poor bulbar function from advanced bulbar amyotrophic lateral sclerosis, poor mental status, inability to clear secretions) (table 4). (See 'Contraindications' above.)

Some patients may require full ventilation via tracheostomy during sleep only with minimal or no support while awake, while others may require mechanical ventilation both during sleep and while awake.

Indications for tracheostomy are provided separately. (See "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Tracheostomy' and "Tracheostomy: Rationale, indications, and contraindications".)

Diaphragm pacers — Diaphragmatic pacing is used in a select group of patients. It is typically limited to those with bilateral diaphragmatic paralysis who have intact phrenic nerve function (eg, patients with high-level cervical cord injury or central hypoventilation). Patients with denervated diaphragms cannot be paced.

The selection of suitable candidates, evaluation, implantation, and complications of diaphragmatic pacing are discussed separately. (See "Pacing the diaphragm: Patient selection, evaluation, implantation, and complications".)

Others (declining or rare use)

Negative pressure ventilators — Negative pressure ventilators are rarely, if ever, used since they are less portable, harder to apply, less effective than NIV, and can worsen obstructive sleep apnea [6]. They are primarily of historical interest.

Negative pressure ventilators like the iron lung (picture 4), which was used in the past for polio patients, or the chest cuirass (picture 5) work by producing an intermittent negative pressure around the thorax and abdomen. The negative pressure is transmitted across the chest wall and diaphragm, thereby assisting inhalation and lung inflation. When the perithoracic pressure returns to atmospheric (or positive in some devices), passive elastic recoil then deflates the lungs.

Abdominal respirators — Intermittent abdominal pressure ventilation (IABPV; also known as "abdominal respirator") was commonly used in the past for patients with bilateral diaphragmatic paralysis. IABPV is limited in its efficacy, especially in patients with acute illness or abnormal body habitus, and is not as effective as NIV.

Abdominal respirators use motion of the abdominal viscera to augment diaphragm excursion. Examples include the intermittent abdominal pressure ventilator ("pneumobelt") (picture 6) and the rocking bed (picture 7) [7,8]. The pneumobelt has an inflatable bladder that intermittently places pressure on the abdomen to assist exhalation; during bladder deflation, the diaphragm moves down to the resting position to assist inspiration. It is maximally effective in the seated position. The rocking bed uses position to augment respiration.

Glossopharyngeal breathing — Although GPB can be used as a way to supplement ventilation (eg, while off mechanical ventilation), it is more commonly used as an expiratory adjunct for augmenting cough strength. Further details on GPB are provided separately [9]. (See "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Lung volume recruitment (assisted inflation maneuvers)'.)

ADJUNCTIVE THERAPY (COUGH SUPPLEMENTATION, NUTRITION) — Patients receiving NIV often need assistance with coughing and secretion clearance. This includes glossopharyngeal breathing (ie, lung volume recruitment maneuver), manually assisted coughing, mechanical insufflation-exsufflation, and secretion mobilization techniques. Further details are provided separately. (See "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Respiratory adjunctive therapy'.)

Other supportive care including nutrition and physical therapy in the care of patients chronically ventilated noninvasively are provided separately. (See "Noninvasive ventilatory support and mechanical insufflation-exsufflation for patients with respiratory muscle dysfunction", section on 'Types of expiratory aids for cough assistance' and "Noninvasive ventilatory support and mechanical insufflation-exsufflation for patients with respiratory muscle dysfunction", section on 'Other considerations'.)

SUMMARY AND RECOMMENDATIONS

●Patient selection – Positive pressure noninvasive ventilation (NIV) is the preferred method of ventilatory support (table 1) in patients with chronic respiratory failure due to respiratory muscle weakness from neuromuscular and chest wall disease (table 2). Subjective clinical findings, objective physiologic tests, and knowledge of the patients preferences are used to determine when NIV is indicated (table 3). (See 'Patient selection' above.)

•Indications – In this population, symptomatic chronic respiratory failure with evidence of nocturnal and/or daytime hypoventilation is the most common indication for chronic ventilatory assistance. Others include early evidence of respiratory muscle weakness in those with progressive disease and symptoms suggesting the concomitant presence of sleep-disordered breathing. (See 'Indications' above and "Respiratory muscle weakness due to neuromuscular disease: Management" and "Symptom-based management of amyotrophic lateral sclerosis", section on 'Respiratory function management' and "Evaluation of sleep-disordered breathing in adult patients with neuromuscular and chest wall disorders".)

•Contraindications – Contraindications include severe facial deformities that limit the application of an NIV interface (although custom-built masks may be available) and inability to protect the upper airway (eg, significant upper airway/bulbar dysfunction, poor mental status, severely weakened cough, inability to clear secretions) (table 4). (See 'Contraindications' above.)

•Initiation – NIV is initiated using an interface (ie, a mask (picture 1) or other device that directs airflow into the upper airway) and a positive pressure ventilator (picture 3). Patients undergo an initial trial, followed by a few weeks of adaptation for acceptance and optimal titration of NIV settings. (See 'Initiation and adaptation' above and "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Practical aspects of initiation" and "Noninvasive ventilation in adults with chronic respiratory failure from neuromuscular and chest wall diseases: Adaptation and follow-up after initiation" and "Noninvasive ventilatory support and mechanical insufflation-exsufflation for patients with respiratory muscle dysfunction".)

•Level of support – The level of support needed is influenced by the underlying indication and disease reversibility. Some patients require nocturnal NIV only, while others need continuous or reducing support. (See 'Chronic long-term use' above and 'Weaning' above.)

●Other options – Other options for ventilatory support are limited in their applicability and have mostly been replaced by positive pressure NIV. These include the following:

•Tracheostomy with positive pressure ventilation – Tracheostomy with positive pressure ventilation is best suited to patients who have an inability to tolerate NIV or patients with contraindications to NIV (eg, patients with poor bulbar function or with poor mental status). (See 'Tracheostomy with positive pressure ventilation' above and "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Tracheostomy' and "Tracheostomy: Rationale, indications, and contraindications".)

•Diaphragmatic pacing – Diaphragmatic pacing may be used in patients with bilateral diaphragmatic paralysis who have intact phrenic nerve function (eg, patients with high-level cervical cord injury or central hypoventilation). (See 'Diaphragm pacers' above and "Pacing the diaphragm: Patient selection, evaluation, implantation, and complications".)

•Others – Others such as negative pressure ventilation and intermittent abdominal pressure ventilation are either of historical interest or rarely used. (See 'Others (declining or rare use)' above.)

●Adjunctive therapy – Patients receiving NIV often need assistance with coughing and secretion clearance. Aids include glossopharyngeal breathing, manually assisted coughing, and cough insufflation-exsufflation. Further details are provided separately. (See "Respiratory muscle weakness due to neuromuscular disease: Management", section on 'Respiratory adjunctive therapy'.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Dr. Robert Basner, who contributed to earlier versions of this topic review.