| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Guest Access | Sign In via User Name/Password
|
|
|
|||||||
Guest Access | Sign In via User Name/Password |
|||||||||
University of Medicine and Dentistry of New Jersey New Jersey Medical School Newark, NJ
Correspondence to: John Robert Bach, MD, FCCP, UMDNJ-New Jersey Medical School, Physical Medicine and Rehabilitation, University Hospital, B-403, 150 Bergen St, Newark, NJ 07871; e-mail: bachjr{at}umdnj.edu
To the Editor:
Limiting amyotrophic lateral sclerosis patients to using low-span bilevel positive airway pressure to treat "sleep-disordered breathing" invariably results in respiratory failure and death or tracheotomy.1 On the other hand, portable volume ventilators can initially rest inspiratory muscles and eventually be used for continuous ventilatory support via 15-mm mouthpieces and nasal or oral interfaces (NIV).2 The advantages of using volume modes rather than pressure modes is that they permit independent "air stacking" to mobilize lung and chest wall tissues to maintain lung compliance and facilitate coughing.3 They can also eliminate any need for tracheostomy, provided that bulbar-innervated muscle dysfunction does not result in aspiration that causes continuous oxyhemoglobin desaturation < 95%.2 The key is in the objective assessment of bulbar-innervated muscle function, something with which Ahuja et al1 are apparently unfamiliar.3 We have decannulated amyotrophic lateral sclerosis patients with no autonomous ability to breathe but with some bulbar-innervated muscle function for up to 10 years before loss of the latter necessitated tracheotomy.4 The recommendation made by Ahuja et al1 for resorting to tracheotomy when the need for NIV exceeds 20 h a day is debatable and certainly not desired by patients.5 "Failure of nasal ventilation... to stabilize gas exchange" is most often a failure of clinicians to use assist/control modes with adequate delivered volumes to continuously maintain normal lung ventilation and use mechanically assisted coughing to clear the airways.4 Beginning low-span bilevel positive airway pressure, when it would only need to be changed to NIV to prevent ventilatory failure, confuses patients and insurance companies and should be discouraged.
Footnotes
The author has reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
The author has reported to the ACCP that no significant conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
References
T. N. Medical College and B. Y. L. Nair Hospital Mumbai, India
Correspondence to: Jyotsna M. Joshi, MD, Professor and Head, Department of Respiratory Medicine, T. N. Medical College and B. Y. L. Nair Hospital, Mumbai 400008, India; e-mail: drjoshijm{at}email.com
To the Editor:
We acknowledge the comments by Dr. Bach regarding our recent article in CHEST (June 2006).1 Although respiratory problems are the main cause of death in patients with amyotrophic lateral sclerosis (ALS), many patients do not receive appropriate and timely management of their respiratory problems.2 The purpose of discussing our case was to highlight sleep-disordered breathing as an important presentation in patients with the bulbar form of ALS.
In patients with ALS, pressure-limited ventilation may be better tolerated than volume-limited ventilation.3 Bach4 has preferred the use of volume-limited ventilation because the air stacking necessary for using some of the expiratory aids cannot be accomplished with pressure-limited devices. Bulbar symptoms are usually associated with intolerance of noninvasive positive-pressure ventilation (NIPPV). However, as in our case, approximately 30% of patients with bulbar symptoms are able to tolerate NIPPV; tolerance of the device in this group of patients confers a survival advantage.3 In a recent study, Lechtzin et al5 suggested that patients with ALS have diaphragmatic weakness and reduced lung compliance, and that some of the beneficial effects of NIPPV therapy may be the result of its effects on lung compliance and the work of breathing.
Management decisions regarding the treatment of ALS patients are often made by emergency/critical care department doctors, and sometimes the patient’s opinion is ignored.2 The statement that "Beginning low span bi-level PAP [positive airway pressure], when it would only need to be changed to NIV [noninvasive ventilation] to prevent ventilatory failure confuses patients and insurance companies," implies that NIV is volume-limited ventilation and that treatment decisions in progressive neuromuscular disease are straightforward. However, NIV can be delivered by a volume ventilator or a bilevel pressure ventilator,6 and in recent years medical decision making has become more complex with conflicts arising frequently between the health-care expenditures system and the patient’s autonomy.7
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
