title: Parasternal intercostal electromyography: a novel tool to assess respiratory load in children.
abstract: Parasternal intercostal muscle electromyography (EMGpara) represents a novel tool to assess respiratory load when volitional techniques are not possible. This study examined the application of EMGpara in healthy, wheezy, and critically ill children.
  
  
  
  Surface EMGpara was measured during tidal breathing in 92 healthy children, 20 wheezy preschool children (with measurements repeated following bronchodilator), and 25 mechanically ventilated children during supported ventilation and on continuous positive airways pressure.
  
  
  
  EMGpara was related to age, height, and weight in the healthy group (r = -0.623, -0.625, -0.641 respectively, all P < 0.0001). An age-based equation for predicted EMGpara was developed and patient data expressed as z-scores. EMGpara was higher in wheezy children prebronchodilator than healthy controls (median interquartile range (IQR) z-score 0.53 (0.07-1.94), P = 0.0073), falling to levels not different to healthy children postbronchodilator (-0.08 (-0.50-1.00)). In the critically ill children, EMGpara was higher (P < 0.0001) than in healthy subjects during both mechanical ventilation (median (IQR) z-score 1.14 (0.33-1.93)) and continuous positive airways pressure (1.88 (0.91-3.03)).
  
  
  
  EMGpara is feasible in children and infants both healthy and diseased, is raised in those with elevated respiratory load, and is responsive to clinical interventions. EMGpara represents a potential method to assess respiratory status in patients conventionally challenging to assess.
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.
authors.forename: Victoria
authors.initials: V
authors.lastname: MacBean
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.
authors.forename: Caroline J
authors.initials: CJ
authors.lastname: Jolley
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Sutton
authors.affiliation: Paediatric Intensive Care Unit, King's College Hospital NHS Foundation Trust, London, UK.
authors.forename: Akash
authors.initials: A
authors.lastname: Deep
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.|National Institute for Health Research (NIHR) Biomedical Research Centre based at Guy's and St Thomas' NHS Foundation Trust and King's College London, London, UK.
authors.forename: Anne
authors.initials: A
authors.lastname: Greenough
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.
authors.forename: John
authors.initials: J
authors.lastname: Moxham
authors.affiliation: Department of Respiratory Medicine, Division of Asthma Allergy and Lung Biology, King's College London, London, UK.
authors.forename: Gerrard F
authors.initials: GF
authors.lastname: Rafferty
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016638:Critical Illness; D004576:Electromyography / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D015278:Intensive Care Units, Pediatric; D008297:Male; D015272:Pulmonary Medicine / Q000295:instrumentation* / Q000379:methods; D012119:Respiration; D012121:Respiration, Artificial / Q000009:adverse effects; D012135:Respiratory Sounds