This second edition provides a substantial overview of the new aspects of noninvasive ventilation that have arisen over the past two decades and includes pathophysiological indications, technology and monitoring. It is intended as an aid for medical teams that are confronted daily with acute and chronic respiratory failure. This book highlights the importance of pressure-support ventilation and sleep investigation in respiratory medicine.
- European Respiratory Monograph
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- Page 3AbstractCorrespondence: D. Georgopoulos, Dept of Intensive Care, University Hospital of Heraklion, University of Crete, Heraklion, Crete 71110, 30 2810392636, Greece. E-mail: email@example.com
Noninvasive mechanical ventilation (NIMV) exerts multiple effects on respiratory (functional residual capacity increase, elastic workload decrease due to dynamic hyperinflation and decrease of inspiratory muscle workload) and cardiovascular systems (left ventricle afterload decrease, venous return and right ventricle preload decrease and O2 consumption decrease). The relative importance of these effects depends on the underlying pathophysiology. Chronic obstructive pulmonary disease and acute cardiogenic pulmonary oedema are two of the most common NIMV indications and are used in the present chapter as an example of rational physiological application of NIMV.
For optimal performance of NIMV, attention must be paid to patient–ventilator interaction during NIMV, by tailoring mode (assist volume control, pressure-support ventilation or proportional assist ventilation) and trigger and cycling-off parameters to the specific patient needs.
In conclusion, when NIMV is rationally applied to carefully chosen patients with the appropriate indication, it has physiological effects similar to those of invasive mechanical ventilation, with fewer complications.
- Page 24AbstractCorrespondence: N. Ambrosino, U.O. Pneumologia, Dipartimento Cardio-Toracico, Azienda Ospedaliero-Universitaria Pisana, Via Paradisa 2, Cisanello, 56124 Pisa39 050996779, Italy. E-mail: firstname.lastname@example.org
Noninvasive positive pressure ventilation (NPPV) and intermittent negative pressure ventilation (INPV) are techniques for delivering mechanical ventilation avoiding the complications of endotracheal intubation (ETI). We review the evidence supporting the use of noninvasive ventilation in acute respiratory failure (ARF) due to chronic obstructive pulmonary disease (COPD).
Strong evidence supports the use of NPPV for ARF to prevent ETI in patients with acute exacerbations of COPD. There is increasing evidence that in ARF due to COPD, INPV is as effective as NPPV and invasive mechanical ventilation and that a combination strategy of INPV and NPPV reduces the need for ETI. Noninvasive ventilation should be applied under close clinical and physiological monitoring for signs of treatment failure, and ETI should be promptly available in such cases. A trained team, careful patient selection and optimal choice of devices can optimise outcome.
Noninvasive mechanical ventilation is increasingly used in the management of ARF due to acute exacerbation of COPD. With limited INPV facilities and expertise in most countries, it seems that NPPV will remain the most widely applied noninvasive ventilatory method, with INPV continuing as a viable option in some centres.
- Page 37AbstractCorrespondence: J.C. Winck, Serviço de Pneumologia, Faculdade de Medicina do Porto, Alameda Prof Hernâni Monteiro, 4200-319 Porto, 351 225512215, Portugal. E-mail: email@example.com
Although noninvasive ventilation (NIV) has an established role for stable patients with restrictive disorders and chronic respiratory failure, evidence from randomised clinical trials in the acute setting is lacking. However, based on the published studies, NIV associated with cough assistance is very effective in neuromuscular diseases (NMDs) with acute respiratory failure (ARF), especially those without significant bulbar dysfunction.
With evidence emerging for myasthenia gravis and Guillain–Barré syndrome, patients with ARF and pre-existing NMD (most already trained in NIV) are the best candidates for a noninvasive respiratory aids protocol.
Secretion-clearance techniques are critically important in managing NMD patients and they may be the weak link in the management of ARF!
Continuous volume cycled ventilation (through a nasal or oral interface) associated with high intensity mechanical in-exsufflation may be very effective in the hands of experienced staff with the proper protocols.
- Page 47AbstractCorrespondence: A. Cuvelier, Service de Pneumologie et Soins Intensifs Respiratoires, Hôpital de Bois-Guillaume, CHU de Rouen, 76031 Rouen, 33 232889094, France. E-mail: firstname.lastname@example.org
Acute hypercapnic respiratory failure in obese patients is an increasing cause of hospitalisation in intensive care units. Despite a few publications on this topic, noninvasive ventilation (NIV) has become the main modality of ventilatory assistance for these patients. NIV specificities are: efficacy of the bilevel mode, mandatory back-up frequency, additional oxygen therapy required, positive inspiratory pressures elevated in patients having obesity–hypoventilation syndrome (OHS) or associated COPD and obstructive sleep apneas (OSAS), positive expiratory pressure elevated in case of OSAS. Flow-preset mode should be tested in case of failure with bilevel mode. In patients with COPD or OHS, an associated nocturnal alveolar hypoventilation at stable state justifies to institute domiciliary NIV. The ventilatory settings will be set according to arterial blood gases and polysomnography a few months after discharge from AHRF.
- Page 60AbstractCorrespondence: M. Ferrer, Servei de Pneumologia, Hospital Clínic, Villarroel 170, 08036 Barcelona, Spain34 932275549. E-mail: email@example.com
The randomised clinical trials of the literature suggest that patients with severe acute hypoxaemic respiratory failure have, in general, a lower likelihood of needing tracheal intubation when noninvasive ventilation, as a support for respiratory failure, is added to the standard medical treatment. However, the effects of noninvasive ventilation on mortality are less evident and the heterogeneity of the different published studies suggests that the efficacy may be different among different populations. Therefore, the results of the literature do not support the routine use of noninvasive ventilation in all patients with severe acute hypoxaemic respiratory failure.
- Page 72AbstractCorrespondence: M.W. Elliott, Dept of Respiratory Medicine, St James's University Hospital, Beckett Street, Leeds, LS9 7TF44 1132066042, UK. E-mail: firstname.lastname@example.org
This chapter reviews the use of positive pressure ventilation (continuous positive airway pressure and bilevel) for patients with acute cardiogenic pulmonary oedema. The incidence at presentation to hospital, its pathophysiology and the physiological basis for the use of positive pressure ventilation is first discussed. Recent meta-analyses are presented, followed by the results of two recent clinical trials, the results of which conflict with the meta-analyses. Possible reasons for this discrepancy are explored.
- Page 94AbstractCorrespondence: G. Hilbert, Département de Réanimation Médicale, Hôpital Pellegrin, F 33076 Bordeaux, France33 556796122. E-mail: email@example.com
Mechanical ventilation is an independent prognostic factor of mortality in immunocompromised patients; thus, to avoid intubation must remain a major objective in this pathology. After several studies showing the feasibility, two prospective randomised and controlled studies demonstrated that noninvasive ventilation (NIV) made it possible to improve the outcome in selected immunocompromised patients admitted in intensive care unit.
Acute respiratory failure (ARF) in immunocompromised patients is a recognised indication of NIV and, according to recent international recommendations (of level I), should be used whenever possible in this indication to reduce the risk of nosocomial pneumonia. Above all, NIV makes it possible to reduce the mortality of the patients of onco-haematology with ARF. The prognosis is still improved when a diagnosis of pneumonitis can be retained and the bronchoscopy can be carried out directly under NIV among the more hypoxaemic patients.
Undoubtedly, ARF in immunocompromised patients belongs to the indications of NIV which require experiment and a good control of the technique justifying, in this indication, the practice of NIV in intensive care units.
- Page 110AbstractCorrespondence: O. Norregaard, Danish Respiratory Centre West, Arhus University Hospital, Norrebrogade 44, Arhus, 8000, 45 89492900, Denmark. E-mail: firstname.lastname@example.org
After some years with increasing use of long-term noninvasive ventilation (NIV) of children with chronic diseases, NIV has, within the very last few years, been emerging as an option for treating children and infants with acute respiratory failure. The prevalent modality is positive pressure ventilation and continuous positive airway pressure, although negative pressure ventilation has been practised. The techniques appear feasible, safe and effective to varying degrees. Data are still very scarce and much research is needed to identify indications, contraindications, best techniques, best modalities, best interfaces and best scenarios. Investigations with long-term follow-up are strongly needed.
- Page 133AbstractCorrespondence: F. Thys, Service des Urgences, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Avenue Hippocrate 10, B-1200 Brussels, Belgium32 27641620. E-mail: email@example.com
An early start of efficient management is vital when treating acute respiratory failure. Noninvasive ventilation (NIV) has its role in this context, for specific indications. Currently, NIV has not yet been established in pre-hospital emergency medicine. Training and experience of operators are the current limiting factors of this approach. Technical ventilation equipment constraints are reduced with the arrival of new ventilators, as they are more ergonomic and efficient and have a better operational autonomy. Recognising the pathophysiology of acute respiratory insufficiency, treatment with NIV seems superior in comparison to treatment with oxygen and medication only for specific indications. The advantages of NIV may lead to reduced morbidity and mortality, as long as attention is paid to possible contraindications.
In the present chapter, the authors propose a summary of the currently available studies and confront it with their expertise, helping to clear up this question.
- Page 143AbstractCorrespondence: C. Girault, Service de Réanimation Médicale, Hôpital Charles Nicolle, Centre Hospitalier Universitaire-Hôpitaux de Rouen, 1 rue de Germont, 76031 Rouen, France33 232888314. E-mail: Christophe.Girault@chu-rouen.fr
The clinical efficacy of noninvasive ventilation (NIV) in the initial management of acute respiratory failure (ARF) led to it being recently proposed as a noninvasive ventilatory strategy following intubation. In this condition, three different indications should be distinguished with potentially different results: NIV application for difficult weaning/extubation from endotracheal mechanical ventilation (ETMV) to reduce the duration of intubation (weaning/extubation strategy); NIV application for post-extubation ARF ("post-extubation NIV"), either to prevent ARF occurrence in patients at risk ("preventative strategy") or to avoid reintubation when this complication occurs ("curative strategy"). Current data show a clinical benefit of NIV, in terms of medical patients’ morbi-mortality, for the preventive as well as the weaning/extubation strategies, mainly in cases of underlying chronic obstructive pulmonary disease. In contrast, the more controversial results observed with NIV for treating post-extubation ARF should lead the clinician to be cautious in this indication. In all cases, NIV applied for weaning from ETMV and post-extubation ARF can only be considered with an experienced team and should not unnecessarily delay the re-intubation time.
- Page 154AbstractCorrespondence: L. Brochard, Réanimation Médicale, Centre Hospitalier Albert Chenevier Henri Mondor, 51 Av. du Maréchal de Lattre de Tassigny, 94010 Créteil Cedex, France33 142079943. E-mail: Laurent.firstname.lastname@example.org
Continuous positive airway pressure (CPAP) is a technique of artificial ventilatory support widely used in the intensive care unit (ICU). CPAP raises intrathoracic pressure, decreases arteriovenous shunting and improves oxygenation and dyspnoea. An advantage of CPAP over modes of mechanical ventilatory assistance is that CPAP does not require patient–ventilator synchronisation. However, pressure support is the most frequently used ventilatory mode during noninvasive ventilation (NIV). A specific problem during noninvasive pressure support ventilation (NPSV) is the presence of leaks around the mask, which lead to discomfort and patient–ventilator asynchrony. An optimal adjustment of ventilatory settings may improve comfort, work of breathing and patient–ventilator interaction, promoting the success of NIV. Other modes of ventilation, developed in order to improve the patient–ventilator interaction can be used during NIV. The proportional assist ventilation is a partial ventilatory assistance based in matching the ventilatory support with neural output of the respiratory centre. No significant systematic superiority over NPSV was found when the two modes of assistance were compared. The neurally adjusted ventilatory assist (NAVA) mode uses the electrical activity of the diaphragm (EAdi). The ventilator is triggered, limited and cycled off directly by EAdi. Neural triggering and cycling off guarantee an optimal patient–ventilator interaction at both the onset and the end of inspiration. The NAVA mode can unload the respiratory muscles; however, only studies on animals and healthy subjects have been carried out. NPSV can be delivered using both ICU ventilators and ventilators specifically dedicated to NIV. Recently, many manufacturers have developed a “mode” specifically designed for NIV. This mode detects leaks and automatically adjusts both the inspiratory and expiratory trigger. These new capabilities may improve patient–ventilator synchrony and NIV tolerance but results are still heterogenous.
- Page 173AbstractCorrespondence: S.M. Maggiore, Dept of Anaesthesiology and Intensive Care, Università Cattolica del Sacro Cuore, Policlinico A. Gemelli, Largo Agostino Gemelli, 8, 00168 Rome39 063013450, Italy. E-mail: email@example.com
Noninvasive ventilation (NIV) reduces the work of breathing, improves gas exchange and may improve clinical outcome in patients with acute respiratory failure (ARF) of various origin. Failure of NIV occurs, however, in ∼20–30% of patients with hypercapnic ARF and in an even higher percentage of patients with hypoxaemic ARF. NIV failure may be due to clinical or technical factors such as the ventilatory mode and settings. Poor adaptation to the interface may also be responsible for some cases of NIV failure. It is therefore important to take into account these technical aspects in order to increase the efficacy of NIV.
Both home and intensive care unit ventilators have been used to delivered NIV but the latter are preferred in the most severe critically ill patients. Three main types of interfaces are currently available in acute situation: facial, nasal and the helmet. The facial mask is generally considered the first choice in terms of efficacy. The helmet is an acceptable alternative to deliver continuous positive airway pressure in selected patients with hypoxaemic ARF. The most rational approach is, however, to adapt the type and the size of the interface on an individual basis. Humidification of inspired gas, often considered of minor relevance, is important to improve patient's comfort. In spite of a theoretical superiority of heated humidifiers over heat and moisture exchangers, particularly in patients with hypercapnic ARF, no study has yet confirmed it to date. Finally, adequate patient selection, preparation and monitoring are crucial in making NIV successful.
- Page 189AbstractCorrespondence: M.W. Elliott , Dept of Respiratory Medicine, St James's University Hospital, Beckett Street, Leeds, LS9 7TF44 113 206 6042, UK. E-mail: firstname.lastname@example.org
This chapter reviews the evidence base for the use of noninvasive ventilation (NIV) in a variety of locations. Ultimately individual circumstances, different between different countries and indeed within an individual country, will determine the best location for an NIV service. Staff training and expertise, however, are key. The need to have a mechanism for monitoring progress and a clear plan, from the outset, of what to do in case of deterioration is stressed. Although the main focus is upon patients with chronic obstructive pulmonary disease, other conditions are touched on.
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- Page 203AbstractCorrespondence: J-F. Muir, Service de Pneumologie et Unité de Soins Intensifs Respiratoires (Hôpital de Bois-Guillaume), CHU de Rouen 76031 Rouen, France, 33 232889000. E-mail: Jean-Francois.Muir@chu-rouen.fr
The key role of noninvasive positive pressure ventilation (NPPV) is well documented in chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure (ARF) since it may avoid endotracheal intubation in >50% of cases when used as the initial treatment. However, there is currently only minimal data to assess usefulness of NPPV in COPD patients on a long-term basis. Even if such studies are difficult to manage, there is clearly a need for prospective studies comparing long-term oxygen therapy and NPPV in the most severe COPD in a large amount of patients and on a real long-term basis of several years. Two randomised, prospective studies are being completed in Europe and the first preliminary results show that NPPV is associated with a reduction of hospitalisation for CRF decompensation.
The main beneficial effect of long-term mechanical ventilation in COPD patients with chronic respiratory failure implies a correction of nocturnal hypoventilation that could persist beyond the ventilation period because of a temporary improvement in CO2 sensitivity that is often blunted in these patients.
The literature suggests considering NPPV for severe COPD patients who present with chronic hypoxia and hypercapnia and develop an unstable respiratory condition. Instability may be appreciated on a clinical basis and confirmed by a progressive worsening of arterial blood gas tensions, leading to frequent cardiorespiratory decompensations with ominous ARF episodes. NPPV should also be considered after an ARF episode successfully treated by noninvasive ventilation but with the impossibility to wean the patient from the ventilator.
Thus, NPPV could be proposed as a preventative treatment in severe COPD patients with unstable respiratory condition associated with fluctuating hypercapnia before, during and after an ARF episode, avoiding the need for a tracheotomy. Adjunction of NPPV to exercise rehabilitation is under evaluation.
- Page 224Abstract
Noninvasive ventilation (NIV) in neuromuscular conditions, associated with respiratory insufficiency, can rapidly improve physiological indices and increase survival. Even in individuals with severe/progressive disorders, NIV may reduce symptom burden and improve quality of life. A combined NIV/cough assist approach may decrease the need for tracheostomy by facilitating sputum clearance, especially at the time of chest infections.
- Page 240AbstractCorrespondence: M. Dreher, Dept of Pneumology, University Hospital Freiburg, Killianstrasse 5, D-79106 Freiburg, Germany49 7612703704. E-mail: email@example.com
Kyphoscoliosis with different aetiologies and post-tuberculosis syndrome are the most common conditions causing restrictive thoracic disorders that predispose patients to the risk of developing chronic hypercapnic respiratory failure. Noninvasive positive pressure ventilation using face masks has become the standard means of treating chronic hypercapnic respiratory failure that arises from restrictive thoracic disorders. Thereby, noninvasive positive pressure ventilation has been shown to improve physiological parameters, most importantly blood gases, and also pulmonary haemodynamics and sleep architecture. In addition, noninvasive positive pressure ventilation is also strongly suggested to improve important outcome parameters such as long-term survival, health-related quality of life, hospitalisation and exercise ability. Therefore, patients with chronic hypercapnic respiratory failure due to restrictive thoracic disorders should be regularly offered long-term noninvasive positive pressure ventilation.
- Page 251AbstractCorrespondence: J-P. Janssens, Centre antituberculeux, Hôpital cantonal, 1211 Geneva 14, Switzerland41 223729929. E-mail: Jean-Paul.Janssens@hcuge.ch
Morbid obesity is associated with an increase in work of breathing and oxygen cost of breathing, a decrease in compliance of the respiratory system, lung volumes, ventilatory drive and respiratory muscle dysfunction. These changes, frequently associated with obstructive apnoea/hypopnoea syndrome, increase the risk of chronic hypercapnic respiratory failure and lead to obesity-hypoventilation syndrome. Untreated obesity-hypoventilation is associated with an increased use of healthcare resources and with a high morbidity and mortality. Although some patients may respond to nocturnal nasal continuous positive airway pressure alone, and correct their daytime hypercapnia, patients with higher body mass index and arterial carbon dioxide tension values will most often require noninvasive positive pressure ventilation. Bilevel positive pressure ventilation is the most frequently chosen option, with high survival rates and a decrease in subsequent hospitalisations for cardiopulmonary failure.
- Page 265AbstractCorrespondence: N. Ambrosino, Pulmonary Unit, Cardio-Thoracic Dept, Azienda Ospedaliero- Universitaria Pisana, Via Paradisa 2, Cisanello, 57124, Pisa39 050996779, Italy. E-mail: firstname.lastname@example.org
Dyspnoea is the most common symptom of patients with chronic obstructive pulmonary disease (COPD). Exercise training can improve dyspnoea and exercise tolerance in these patients in whom higher intensity levels may be prevented by extreme breathlessness and/or peripheral muscle fatigue. As mechanical loading and inspiratory muscle dysfunction contribute to dyspnoea in COPD, assisted ventilation should provide a symptomatic benefit by unloading and assisting such overburdened ventilatory muscles.
Continuous positive airway pressure and different modalities of noninvasive positive pressure ventilation (NPPV) applied during exercise resulted in improvement of dyspnoea and exercise tolerance. Inspiratory muscle unloading and reduction in intrinsic positive end-expiratory pressure have been considered among mechanisms underlying these effects in COPD patients. Nevertheless, the role of NPPV in pulmonary rehabilitation, if any, is still controversial. The addition of nocturnal domiciliary NPPV during a day-time exercise programme in patients with severe COPD resulted in an improvement in exercise tolerance and quality of life.
- Page 272AbstractCorrespondence: B. Fauroux, AP-HP, Hopital Armand Trousseau, Paediatric Pulmonary Dept, Research Unit INSERM UMR S-893 Equipe 12, Université Pierre et Marie Curie-Paris 6, 28 Avenue du Docteur Arnold Netter, Paris, F-75012 France33 144736174. E-mail: email@example.com
Domiciliary noninvasive positive pressure ventilation (NPPV) is increasingly used in children. Three categories of respiratory system dysfunction can justify long term NPPV: an increase in respiratory load (due to intrinsic cardiopulmonary disorders or skeletal deformities); respiratory muscle weakness (due to neuromuscular diseases or spinal cord injury); or failure of neurologic control of ventilation (such as the central hypoventilation syndrome). In these different diseases, the role of NPPV will be to respectively unload the respiratory muscles, to replace the respiratory muscles or to replace central drive, in order to correct alveolar hypoventilation. The benefit of NPPV on nocturnal and daytime gas exchange has been demonstrated in children. Other effects, such as an improvement of lung function, respiratory muscle performance or respiratory mechanics, are less well documented. The effect of NPPV on lung growth is an important point that needs to be investigated. The type of equipment and the specific ventilator settings that should be chosen remain a matter of debate and evolve more rapidly with industry capability than with clear indications available from scientific trials. The major advantage of NPPV is that it can be applied at home, combining greater potential for psychosocial development and family function, at a lesser cost. The use of home NPPV requires appropriate diagnostic procedures, appropriate titration of the ventilator, co-operative and educated families and a careful, well-organised follow up. NPPV represents a challenge for the future whose objective is to improve the well-being of a child with chronic respiratory insufficiency and his or her family.
- Page 287AbstractCorrespondence: S. Nava, Respiratory Intensive Care Unit, Fondazione Salvatore Maugeri, Via Maugeri n.10, 27100 Pavia, Italy39 0382592075. E-mail: firstname.lastname@example.org
As pulmonary physicians, especially those dealing with mechanical ventilation, we are facing the problem of withholding and withdrawing life support in terminally ill patients affected by acute or chronic respiratory disorders every day.
The overall incidence of these practices in Europe is only partially known and, even more importantly, it has been shown that there are important differences between countries or regions, reflecting the absence of a common strategy even within the European Community.
The “shared decision” taken together by physicians, nurses and the patient's family may be the best approach to these decisions. There is good evidence that noninvasive ventilation (NIV) may be used in terminally ill patients with different objectives, such as: 1) life support with no preset limitations on life-sustaining treatment; 2) life support when the patients decided to forego intubation (DNI); and 3) a "pure" palliative measure. Up to 30% of end-stage chronic respiratory patients are receiving NIV in the last days of life, solely to relieve dyspnoea, and this "ceiling" practice has also been applied to end-stage cancer patients. About 50% of DNI patients with acute respiratory failure may also be successfully treated and discharged from the hospital, mainly if affected by chronic obstructive pulmonary disease or chronic heart failure. The success of NIV is strictly dependent on the experience of the staff involved, and the patients should be allowed to withdraw from the treatment in every instance.
- Page 307AbstractCorrespondence: P. Jolliet, Service des soins intensifs, Hôpital Cantonal Universitaire, 1211 Geneva 14, Switzerland41 223729105. E-mail: email@example.com
The increasing number of patients receiving long-term home ventilation over the years has fuelled demand for the development of reliable, compact, powerful and quiet home ventilators. Manufacturers have been quick to respond and there is now an abundant offer of such machines on the market. However, this large range can sometimes make choosing the appropriate device difficult for physicians. Bench testing can provide valuable data to assist in that decision and several such studies have been published in recent years. However, the clinical relevance of these tests must also be determined through pathophysiological and clinical studies. The combined data stemming from these two complementary approaches should help clinicians in making the right decision when choosing a ventilator for an individual patient in need of chronic home ventilation.
- Page 319AbstractCorrespondence: J.H. Storre, Abteilung Pneumologie der Medizinischen Klinik, Klinikum der Albert-Ludwigs-Universität, Killianstrasse 5, D-79106 Freiburg in Breisgau49 7612703704, Germany. E-mail: Jan.Storre@uniklinik-freiburg.de, B. Schönhofer, Abteilung für Pneumologie und Internistische Intensivmedizin, Krankenhaus Oststadt-Heidehaus, Klinikum Region Hanover, Podbielskistraße 380, D-30659 Hanover, Germany, 49 5113779. E-mail: Bernd.Schoenhofer@t-online.de
Negative pressure ventilation (NPV) was the first reported form of noninvasive ventilation (NIV) to be widely applied to chronic respiratory failure (CRF). However, during the past decades, NPV has gradually lost its former impact and, apart from in a few centres, has been almost completely replaced by positive pressure ventilation (PPV) modes.
The existing plethora of terminology describing NIV modes can sometimes be confusing, especially with respect to ventilators. Pressure-targeted ventilation (PTV) and volume-targeted ventilation (VTV) are the main modes of NIV; Both types can be used in an assisted or controlled setting.
PTV has surpassed VTV in recent years as the treatment option for CRF. Both modes have been successfully applied to NIV in CRF. However, PTV has become the preferred mode due to the higher comfort level for the patient, as well as the lower costs and the compensation it provides for mild-to-moderate mask or mouth leaks. Recently, hybrid modes of PTV and VTV were introduced.
The choice of ventilator and its setting should address different pathophysiological aspects of the underlying disease, of which is variable amongst CRF patients; in patients with COPD, the expiration time should be set at a higher level to avoid air trapping, while higher pressures may be useful to achieve a sufficient tidal volume. Furthermore, the addition of an positive end-expiratory pressure (PEEP) may be helpful to offset intrinsic PEEP in these patients. Various studies have shown that a controlled mode of ventilation is useful and well tolerated by all patients, irrespective of the underlying disease. When a controlled mode of ventilation is favoured, an assist-controlled mode is suggested to increase the patients' subjective tolerance. However, an individualised approach to each patient is beneficial and further studies investigating ventilator settings are needed to continually improve recommendations.
The interface between patient and ventilator is crucial for the success of NIV. In various studies, different interfaces have been used with success. However, despite its high clinical impact, the choice of different interfaces has received little scientific attention. A variety of masks are now available, and manufacturers continue to improve mask design. The majority of interfaces is represented by commercial or custom-made nasal masks and oronasal masks. In special indications, nasal pillows or mouthpieces are used. It is suggested that nasal masks should be used prior to oronasal masks in CRF, since there are fewer limitations and communication with the patients is more convenient. In contrast, if patients are mouth breathers, an oronasal mask is favoured. In patients using nasal masks, leaks can occur through an open mouth, especially during night; these leaks can lead to NIV insufficiency, where both the quality of ventilation and sleep may be reduced. In this case, changing the interface to an oronasal mask should be considered. In general, mechanical ventilation can lead to dryness of the upper airway. Therefore, nasal resistance may be an important reason for reduced compliance, which may be compensated by additional humidification.
- Page 338AbstractCorrespondence: P. Navalesi, SCDU Anestesia, Terapia Intensiva e Rianimazione Generate, Azienda Ospedaliero-Universitaria ‘Maggiore della Caritàrsquo;, Corso Mazzini 18, 28100 Novara, Italy, 39 3213733406. E-mail: firstname.lastname@example.org
The choice of the interface is crucial for the success of noninvasive ventilation (NIV) in both the acute and chronic setting. Type (oral, nasal, oro-nasal), size, design, material and securing system of the interface may affect the patient's comfort with respect to many aspects, such as air-leaks, claustrophobia, skin erythema, eye irritation and skin breakdown. Although the continuous development of new products has increased the availability of interfaces and the chance to meet different requirements, in patients necessitating several daily hours of NIV, the rotational use of different interfaces remains an excellent strategy to decrease the risk of skin breakdown.
While the importance of heating and humidification for long-term invasive mechanical ventilation is well known, it is less recognised for the patient receiving long term NIV. Recent work, however, suggests that, in the presence of airleaks, cold dry air increases nasal resistance, causes nasal symptoms and reduces the patient's compliance to NIV, and that heated humidification has the potential to reduce these adverse effects.
- Page 350AbstractCorrespondence: J-L. Pépin, Pôle Rééducation et Physiologie, CHU de Grenoble, BP 217 X, 38043, Grenoble, France, 33 476765586. E-mail: JPepin@chu-grenoble.fr
The present chapter first reiterates the different mechanisms underlying ventilatory changes occurring during sleep and the capability of noninvasive ventilation (NIV) in correcting abnormal respiratory events and improving sleep quality in different diseases. In order to ensure long-term NIV efficiency, appropriate strategies for monitoring ventilation and sleep, during NIV treatment, are proposed. Different tools, allowing monitoring of chronic respiratory failure patients treated using long-term home NIV, and their respective interests and limitations are successively reviewed. Tools only aiming to recognise the consequences of residual events, such as oxygen desaturations or increases in nocturnal transcutaneous carbon dioxide tension are distinguished compared with more complex strategies, such as respiratory polygraphy and polysomnography. Finally, specific software, designed by ventilator manufacturers for at-home monitoring, and the use of flow signals included in NIV devices, are remarked upon. These data may provide useful information for clinicians.
- Page 367AbstractCorrespondence: J. Escarrabill, Institut d’Estudis de la Salut, C/ Roc Boronat, 81-95 1st floor, 08005 Barcelona34 932607576, Spain. E-mail: email@example.com
In patients with complex needs, such as patients with noninvasive ventilation (NIV), the coordination of the caregivers and the planning of the process of discharge are especially important. The care team must make sure that the patient (and the caregiver) is fully informed, that they retain control over the decisions, that they participate in the care programme and that individual values are respected in the process of care.
The adaptation to the ventilation is a process that can take several days and it requires the collaboration of the patient and the caregiver. The discharge plan is defined as designing a customised plan for each patient that takes place before leaving the hospital (or before starting independent treatment at home). The discharge plan must contemplate the simplest option that obtains the maximum benefits. The figure of the nurse case manager plays a vital role in implementing the plan of care for patients with NIV.
- Page 377AbstractCorrespondence: E.M. Clini, Dept of Oncology, Haematology and Pneumology, University of Modena, Ospedale Villa Pineta, Via Gaiato 127, 41026, Pavullo n/F (MO)39 053642039, Italy. E-mail: firstname.lastname@example.org
The expansion of home mechanical ventilation (HMV) in the last 15 yrs was stimulated by the introduction of noninvasive mask ventilation and the recognition that more patient groups could benefit.
In the management of healthcare resources, cost-analysis currently represents a method for evaluation of the expenditure due to the effects on health of a new (or specific) intervention and for assessing it in the economic perspective. Disability-adjusted life-yrs, healthy-yr equivalents and quality-adjusted life-yrs are all time-based measures of health that include the impact of interventions on years of life lost due to premature mortality and years of life lived with a nonfatal health outcome, weighted by the severity of that outcome.
Although the effectiveness of noninvasive HMV has been addressed, the impact of this treatment on the overall costs has not been clearly reported or demonstrated and very few data based on a true economic analysis in patients under noninvasive HMV have been published. Direct and (partially) indirect cost calculations have been observed and reported, especially in chronic obstructive pulmonary disease patients under noninvasive HMV. The most recent data underline the large impact of noninvasive HMV on both patient outcome (reduction of recurrent admissions and increase in quality of life) and family burden (unemployment, financial and social issues), thus prompting further studies with appropriate cost-effectiveness and/or cost-utility analysis.
- Page 392AbstractCorrespondence: J.A. Wedzicha, Academic Unit of Respiratory Medicine, Royal Free and University College Medical School, Rowland Hill Street, London, NW3 2PF, UK44 2074726141. E-mail: email@example.com
There has been a dramatic rise in the use of home mechanical ventilation (HMV) in Europe over the last two decades driven by the widening indications for HMV and increasing prevalence of chronic respiratory failure. The implementation of HMV differs widely among European countries and it would be desirable to standardise provision in order to provide equitable patient outcomes.
- Page 400Abstract
Noninvasive ventilation using intermittent positive pressure (NIPPV) which appeared in the 1980s for long-term home ventilation is now routinely used both at home and in hospital for chronic and acute respiratory failure. New indications for NIPPV have been validated but many remain to be better known with forthcoming studies. In the long term, the role in chronic obstructive pulmonary disease, in obesity-hypoventilation syndrome and in periodic breathing due to severe cardiac insufficiency, will be clarified. In acute situations, the place to apply NIPPV according to the severity is an important issue for hospital organisations. Clinical indications will be established and/or clarified, such as pneumonia occurring on normal lung, severe asthma, immune compromised patients, weaning from invasive ventilation and NIPPV as the ceiling to offer ventilatory assistance. Technical progress will also continue to appear concerning the ventilators both for chronic and acute using. New ventilators will provide a better synchronisation between patient and ventilator and would confirm the predominant use of high speed turbine as the pressure and flow generator.