MD Conference Express ATS 2013 - (Page 8)

FEATURE Nocturnal Noninvasive Ventilation Improves Outcomes in Multiple Disorders Written by Emma Hitt, PhD 8 July 2013 demonstrated a significant trend in decreased mortality with nNIV treatment [McEvoy RD et al. Thorax 2009]. In addition, Prof. Nava highlighted a meta-analysis that analyzed other parameters such as sleep efficiency, CO2 partial pressure, forced expiratory volume and forced vital capacity (FVC) reported no significant difference in mortality with nNIV treatment, as compared with long-term oxygen therapy [Wijkstra PJ et al. Chest 2003]. Prof. Nava suggested that one reason that few COPD patients respond to nNIV may be setting related. The three largest trials reported in the literature that demonstrated no benefit with nNIV treatment used an inspiratory PAP (IPAP) and expiratory PAP (EPAP) of 12 cm H2O and 4 cm H2O [Casanova C et al. Chest 2000], and 14 cm H2O and 2 cm H2O [Clini E et al. Eur Respir J 2002]; whereas a study that demonstrated nNIV benefit used an IPAP and EPAP of 13 cm H2O and 5 cm H2O [Mc Evoy RD et al. Thorax 2009]. Prof. Nava highlighted a study that used more aggressive pressures with an IPAP of 31 mm Hg that resulted in a significantly lower partial pressure of CO2 during spontaneous breathing after the discontinuation of nNIV (Figure 1) [Windisch W et al. Respir Physiol Neurobiol 2006]. This approach however may harm the cardiovascular system, since when compared with lower levels of IPAP, the “German approach” resulted in a significant reduction in cardiac output [Lukácsovits J et al. Eur Respir J 2012]. Figure 1. Aggressive IPAP in nNIV Decreases CO2 Partial Pressure in Patients With COPD PaCO2 During Spontaneous Breathing (mm Hg) Nocturnal noninvasive ventilation (nNIV) is used for treatment of multiple pathologies such as neuromuscular disorders, sleep apneas, restrictive thoracic disorders, chronic obstructive pulmonary disease (COPD), and obesity-hypoventilation syndrome with the goals of increasing gas exchange, decreasing respiratory muscle fatigue, decreasing stress, and increasing comfort and sleep. Sairam Parthasarthy, MD, University of Arizona, Tucson, Arizona, USA, presented on the basics of nNIV and highlighted areas of emerging research and new challenges in the field. Positive airway pressure (PAP) results in greater thoracic and lung volume, which leads to increased cardiac output, reduced venous return, and reducing afterload [AntonescuTurcu A, Parthasarthy S. Respir Care 2010]. Despite such favorable physiological effects, continuous PAP (CPAP) therapy resulted in a similar rate of transplantation-free survival, as compared with a control group [Bradley TD et al. N Engl J Med 2005]. Dr. Parthasarthy said that such a finding may be due to residual central sleep apnea despite CPAP therapy and that a different method of respiratory support, called adaptive servo-ventilation (ASV) can significantly reduce central sleep apnea when compared with control populations in patients with heart failure [Teschler H et al. Am J Resp Crit Care Med 2001; Morgenthaler TI et al. Sleep 2007; Arzt M et al. Chest 2008; Javaheri S et al. Sleep 2011]. Such amelioration of central sleep apnea was observed across various manufacturers of these devices and across a variety settings. Dr. Parthasarthy also addressed the question of how to determine the target tidal volume in patients with nocturnal hypoventilation and challenges that may prevent achieving the target. For example, an air leak tracing during polysomnography can indicate the degree of air-leak present during NIV titration, and that such an air-leak can reduce patient adherence due to diminished performance of the system [Valentin A et al. Sleep 2011]. Stefano Nava, MD, Bologna University Hospital Authority St. Orsola-Malpighi Polyclinic, Bologna, Italy, discussed the controversial issue of nNIV use in patients with COPD and overlap syndrome (COPD and sleep apnea). Prof. Nava pointed out that, at the present time, the longterm use of nNIV is not recommended in COPD patients for the treatment of chronic respiratory failure due to several evidence-based factors. A recent study demonstrated that chronic nNIV did not improve mortality in patients with COPD [Shi JX et al. Chin Med J (Engl) 2013] and another study nNIV 60 Controls 58 p=0.26 56 54 nNIV (assPCV) Mean IPAP 31±7 mbar Mean bf 21±2 /min 52 50 p<0.001 48 46 Baseline 0 0.5 1 3 Time After Cessation (Hours) 7 11 15 nNIV=nocturnal noninvasive ventilation; IPAP=inspiratory positive airway pressure. Reproduced from Windisch W et al. Nocturnal non-invasive positive pressure ventilation: Physiological effects on spontaneous breathing. Respir Physiol Neurobiol 2006;150(2-3):251260. With permission from Elsevier. Finally, Prof. Nava pointed out that patients with overlap syndrome appear to respond well to nNIV. Several www.mdconferencexpress.com http://www.mdconferencexpress.com

Table of Contents for the Digital Edition of MD Conference Express ATS 2013

MD Conference Express ATS 2013
Contents
Prevention and Early Treatment of Acute Lung Injury
Nocturnal Noninvasive Ventilation Improves Outcomes in Multiple Disorders
Hospital Readmissions: Challenges and Opportunities
EBUS-TBNA: Accurate and Safe for Detecting Sarcoidosis
Data Link Obstructive Sleep Apnea and Type 2 Diabetes
Statin Use Improves Respiratory-Related Mortality in Patients With COPD
Addition of Spironolactone to Ambrisentan May Be a Novel Treatment Strategy to Improve Outcome in Patients With PAH
Haloperidol Does Not Prevent Delirium in Ventilated ICU Patients
Beraprost Plus Sildenafil Effective in Pulmonary Arterial Hypertension
Dupilumab Is Safe and Effective for Controlling Asthma Attacks
Once-Daily QVA149 Improves Breathlessness in COPD Patients
CPAP in CVD and OSA Does Not Significantly Improve Cardiovascular Biomarkers
CPAP Reduces BP in Patients With Resistant Hypertension and Obstructive Sleep Apnea
Effects of Obesity on COPD
Pulmonary Embolism
Ventilator-Associated Pneumonia
Lung Cancer Screening
Idiopathic Pulmonary Fibrosis
Non-Small-Cell Lung Cancer

MD Conference Express ATS 2013

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