The study protocol was approved by Giannina Gaslini Institute Ethics Committee in accordance with Italian legislation and according to the principles of the Helsinki Declaration. Nocturnal evaluation was performed during the evening of the scheduled hospital admission. Patients with acute upper or lower airway infections were excluded. As per British Thoracic Society guidelines, 1 this threshold is considered an indicator to commence nocturnal respiratory assessment in NMD. All of the patients had genetically confirmed paediatric-onset NMD and a concomitant restrictive respiratory deficiency, defined as a forced vital capacity (FVC) below 60% of the predicted value. Gaslini Pediatric Institute, Genova over a 6-year period from 2009 to 2014. We performed a retrospective study of 46 consecutive inpatients with NMD who were referred to the Neuromuscular Unit at G. The main aim of this study was to assess whether the current indicators of impairment of gas exchange, namely nocturnal hypoxemia, daytime PaCO 2, and clinical symptoms, may underestimate the presence of NH in paediatric-onset NMD. 13 – 15 If this is the case, this finding could further expand the indications for NIV support. Few studies have specifically evaluated whether nocturnal hypercapnia is present in clinically asymptomatic patients with NMD. 8, 9 Despite published guidelines, there is still debate regarding the correct timing to start NIV 10 – 12. 1, 3, 7 Prompt use of NIV is effective in reducing nocturnal hypoventilation and its progression towards daytime hypercapnia. 6 Early recognition of NH is crucial because, if undiagnosed and thus untreated by non-invasive ventilation (NIV), NH can progress to daytime hypercapnia (partial carbon dioxide pressure > 45 mmHg in blood gases 1 – 3) or clinical symptoms related to hypoventilation.
5 Because clinical symptoms of NH can be insidious and not always present, daytime clinical assessments can be unreliable in early detection of respiratory failure. 3, 4 In patients with NMD, a correlation between a reduction in VC and progression of sleep-disordered breathing has been shown. Various definitions of NH have been proposed, but which definition best relates to prognosis remains unclear. 1, 2 The first manifestation of chronic respiratory insufficiency in neuromuscular disorders (NMD) is nocturnal hypoventilation (NH) occurring in rapid eye movement sleep. This deficiency is characterized by a reduction in vital capacity (VC), total lung capacity, and functional residual capacity with a variable course among different disorders. Neuromuscular weakness often leads to a chronic restrictive respiratory deficiency.
0 kommentar(er)
