Pediatric Pulmonology 49:1043–1044 (2014)
Letter to the Editor
Noninvasive mechanical ventilation and mechanical in-exsufflator: A definitive solid combination? Some key methodology considerations
To the Editor:
Among the pediatric patients with neuromuscular conditions who develop acute hypoxemic respiratory failure (AHRF), management of airway secretions may influence hospital outcomes. In particular the patients who require invasive mechanical ventilation (IMV) are at risk of developing ventilator-associated pneumonia.1 However, in certain cases application of noninvasive ventilation (NIV) as a first line strategy to avoid IMV can be accommodated. Application of NIV in the management of pediatric patients with neuromuscular conditions who have AHRF has not gained widespread interest due to conflicting reports of high rates of NIV failure. One of the reasons for failure could be the presence of excessive secretions. In this situation, the mechanical in-exsufflator (MI-E) is recommended to control airway secretion, augment reflex cough capacity and prevent NIV failure.2 However, the description of uses and success of such devices in conjunction with NIV is limited. In an original study, Chen et al. analyzed the use of combined NIV and MI-E in the treatment of AHRF among pediatric patients with neuromuscular conditions.3 We would like to comment and applaud efforts of the authors in describing their experience. We would like to comment regarding methodological issues that may TABLE 1— Key Methodology During NIV and MI-E Session2,3 (1) Assessment of effective management of airway bronchial secretions (2) Use of proper determination of MI-E parameters combined with NIV setting selected evaluation of breathing pattern (3) Control oxygenation: (a) MI-E application requires NIV mask disconnection, resulting in loss of positive pressure, alveolar collapse and desaturation (b) MI-E devices do not have entrained oxygen and rapid desaturation episode will require immediate reconnection to NIV (4) Control of ventilation. Additionally, application of measurements such as transcutaneous carbon dioxide tension (PtcCO2), and independently assessed auscultation score could be a recommendations in severe patients
ß 2014 Wiley Periodicals, Inc.
influence the use of this combination NIV and MI-E. These remarks are relevant for achieving effective airways clearance (Table 1).4 First, the population enrolled in their study needs clarification. The sample size in this study is relatively small with a wide range of ages of participants and with heterogeneous neuromuscular diseases. It is not clear how many patients had bulbar involvement and how effective their capacity is to handle secretions. Second, It is unclear whether pulmonary function tests were performed before during or after the application of NIV and NI-E because measurements such as maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced expiratory flow (FEF) 25–75, and the Peak Expiratory flow rate (PEFR) are essential to determining the effectiveness of the response during NIV and MI-E application.5 Second, it is unclear whether these patients were sedated. We know that sedation may influence breathing pattern, respiratory muscle fatigue or effective cough reflex. In particular, sedation with chloral hydrate has the drawback, like benzodiazepines, that there is no antidote for excessive dosing. Third, it is unclear how MI-E was applied in practical terms. Was it applied cyclically or continuously? How was the temporary period of acute oxygen desaturation and alveolar collapse managed during the application and withdrawal of therapy? Finally, information is lacking regarding the training of the healthcare providers during application of this combination. It will be useful to know the uptake, adherence, compliance, feasibility and family acceptance of this technique in their unit to help guide other units contemplating such practice.2,3
Conflict of interest: None.
Correspondence to: Antonio M. Esquinas, MD, PhD, FCCP, International Fellow AARC, Avenida Marques de Los Velez s/n, Murcia 30.008, Spain. E-mail: [email protected] Received 23 September 2013; Revised 19 January 2014; Accepted 27 January 2014. DOI 10.1002/ppul.23024 Published online 9 March 2014 in Wiley Online Library (wileyonlinelibrary.com).
1044
Esquinas and Shah
We consider that the combined use of NIV and MI-E in pediatric patients with neuromuscular conditions who develop AHRF has an important role to play. Clarification or information about the above issues will benefit the discussion among patients, families and the scientific community to permit the best design of future randomized controlled trials that are needed to assess the safety and efficacy of NIV and MI-E in AHRF. —ANTONIO M. ESQUINAS,
MD, PhD, FCCP, INTERNATIONAL FELLOW AARC
Intensive Care Unit Hospital Morales Meseguer Murcia, Spain —PRAKESH S. SHAH, MSc, MBBS, MD, DCH, MRCP, FRCPC Departments of Paediatrics and HPME University of Toronto, Mount Sinai Hospital Toronto, ON, Canada
Pediatric Pulmonology
REFERENCES 1. Panitch HB. Airway clearance in children with neuromuscular weakness. Curr Opin Pediatr 2006;3:277–281. 2. Chatwin M, Simonds AK. The addition of mechanical insufflation/ exsufflation shortens airway-clearance sessions in neuromuscular patients with chest infection. Respir Care 2009;11:1473– 1479. 3. Chen TH, Hsu JH, Wu JR, Dai ZK, Chen IC, Liang WC, Yang SN, Jong YJ. Combined noninvasive ventilation and mechanical inexsufflator in the treatment of pediatric acute neuromuscular respiratory failure. Pediatr Pulmonol 2013. doi: 10.1002/ ppul.22827 4. Homnick DN. Mechanical insufflation-exsufflation for airway mucus clearance. Respir Care 2007;10:1296–1305. 5. Senent C, Golmard JL, Salachas F, Chiner E, Morelot-Panzini C, Meninger V, Lamouroux C, Similowski T, GonzalezBermejo J. A comparison of assisted cough techniques in stable patients with severe respiratory insufficiency due to amyotrophic lateral sclerosis. Amyotroph Lateral Scler 2011;1: 26–32.
Letter to the Editor
Noninvasive mechanical ventilation and mechanical in-exsufflator: A definitive solid combination? Some key methodology considerations
To the Editor:
Among the pediatric patients with neuromuscular conditions who develop acute hypoxemic respiratory failure (AHRF), management of airway secretions may influence hospital outcomes. In particular the patients who require invasive mechanical ventilation (IMV) are at risk of developing ventilator-associated pneumonia.1 However, in certain cases application of noninvasive ventilation (NIV) as a first line strategy to avoid IMV can be accommodated. Application of NIV in the management of pediatric patients with neuromuscular conditions who have AHRF has not gained widespread interest due to conflicting reports of high rates of NIV failure. One of the reasons for failure could be the presence of excessive secretions. In this situation, the mechanical in-exsufflator (MI-E) is recommended to control airway secretion, augment reflex cough capacity and prevent NIV failure.2 However, the description of uses and success of such devices in conjunction with NIV is limited. In an original study, Chen et al. analyzed the use of combined NIV and MI-E in the treatment of AHRF among pediatric patients with neuromuscular conditions.3 We would like to comment and applaud efforts of the authors in describing their experience. We would like to comment regarding methodological issues that may TABLE 1— Key Methodology During NIV and MI-E Session2,3 (1) Assessment of effective management of airway bronchial secretions (2) Use of proper determination of MI-E parameters combined with NIV setting selected evaluation of breathing pattern (3) Control oxygenation: (a) MI-E application requires NIV mask disconnection, resulting in loss of positive pressure, alveolar collapse and desaturation (b) MI-E devices do not have entrained oxygen and rapid desaturation episode will require immediate reconnection to NIV (4) Control of ventilation. Additionally, application of measurements such as transcutaneous carbon dioxide tension (PtcCO2), and independently assessed auscultation score could be a recommendations in severe patients
ß 2014 Wiley Periodicals, Inc.
influence the use of this combination NIV and MI-E. These remarks are relevant for achieving effective airways clearance (Table 1).4 First, the population enrolled in their study needs clarification. The sample size in this study is relatively small with a wide range of ages of participants and with heterogeneous neuromuscular diseases. It is not clear how many patients had bulbar involvement and how effective their capacity is to handle secretions. Second, It is unclear whether pulmonary function tests were performed before during or after the application of NIV and NI-E because measurements such as maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), forced expiratory flow (FEF) 25–75, and the Peak Expiratory flow rate (PEFR) are essential to determining the effectiveness of the response during NIV and MI-E application.5 Second, it is unclear whether these patients were sedated. We know that sedation may influence breathing pattern, respiratory muscle fatigue or effective cough reflex. In particular, sedation with chloral hydrate has the drawback, like benzodiazepines, that there is no antidote for excessive dosing. Third, it is unclear how MI-E was applied in practical terms. Was it applied cyclically or continuously? How was the temporary period of acute oxygen desaturation and alveolar collapse managed during the application and withdrawal of therapy? Finally, information is lacking regarding the training of the healthcare providers during application of this combination. It will be useful to know the uptake, adherence, compliance, feasibility and family acceptance of this technique in their unit to help guide other units contemplating such practice.2,3
Conflict of interest: None.
Correspondence to: Antonio M. Esquinas, MD, PhD, FCCP, International Fellow AARC, Avenida Marques de Los Velez s/n, Murcia 30.008, Spain. E-mail: [email protected] Received 23 September 2013; Revised 19 January 2014; Accepted 27 January 2014. DOI 10.1002/ppul.23024 Published online 9 March 2014 in Wiley Online Library (wileyonlinelibrary.com).
1044
Esquinas and Shah
We consider that the combined use of NIV and MI-E in pediatric patients with neuromuscular conditions who develop AHRF has an important role to play. Clarification or information about the above issues will benefit the discussion among patients, families and the scientific community to permit the best design of future randomized controlled trials that are needed to assess the safety and efficacy of NIV and MI-E in AHRF. —ANTONIO M. ESQUINAS,
MD, PhD, FCCP, INTERNATIONAL FELLOW AARC
Intensive Care Unit Hospital Morales Meseguer Murcia, Spain —PRAKESH S. SHAH, MSc, MBBS, MD, DCH, MRCP, FRCPC Departments of Paediatrics and HPME University of Toronto, Mount Sinai Hospital Toronto, ON, Canada
Pediatric Pulmonology
REFERENCES 1. Panitch HB. Airway clearance in children with neuromuscular weakness. Curr Opin Pediatr 2006;3:277–281. 2. Chatwin M, Simonds AK. The addition of mechanical insufflation/ exsufflation shortens airway-clearance sessions in neuromuscular patients with chest infection. Respir Care 2009;11:1473– 1479. 3. Chen TH, Hsu JH, Wu JR, Dai ZK, Chen IC, Liang WC, Yang SN, Jong YJ. Combined noninvasive ventilation and mechanical inexsufflator in the treatment of pediatric acute neuromuscular respiratory failure. Pediatr Pulmonol 2013. doi: 10.1002/ ppul.22827 4. Homnick DN. Mechanical insufflation-exsufflation for airway mucus clearance. Respir Care 2007;10:1296–1305. 5. Senent C, Golmard JL, Salachas F, Chiner E, Morelot-Panzini C, Meninger V, Lamouroux C, Similowski T, GonzalezBermejo J. A comparison of assisted cough techniques in stable patients with severe respiratory insufficiency due to amyotrophic lateral sclerosis. Amyotroph Lateral Scler 2011;1: 26–32.
