Paediatric Airway Emergencies DR. D. Mannion. Chairman Dept of Anaesthesia & Critical Care OLCH Crumlin 9/21/2018 IARNA 2010

Objectives Why are children different? Anatomy Physiology Routine management of paediatric airway Common problems Management of difficult airway. Anticipated Unanticipated 9/21/2018 IARNA 2010

ANATOMY Supra Glottic Narrow nares Large tongue Epiglottis large and floppy Larynx more anterior Larynx more cephalad C3 – C4 Sub Glottic Narrow cricoid ring Trachea 2-5 cm short Bronchi more horizontal Small cricothyroid membrane Mobile compliant trachea 9/21/2018 IARNA 2010

PHYSIOLOGY Lung volume smaller in proportion Metabolic rate is twice an adults Greater VO2 6ml/kg v 3 ml/kg in adult Vent requirement per unit lung is greater Airway resistance is greater due to small airways High respiratory rates 9/21/2018 IARNA 2010

Physiology – practical implications Great for inhalational inductions Great for maintaining inhalational anaesthesia BUT If airway obstructed they rapidly desaturate. 9/21/2018 IARNA 2010

Also Neonates obligate nasal breathers until 2-5 months of age. Tonsils and adenoids appear at 2 years and reach max size at 4 – 7 years. Snoring, sleep apnoea and upper airway obstruction when unconscious. 9/21/2018 IARNA 2010

COMMON DIFICULTIES Position Mask Neutral position – small role under shoulders Over extended neck worsens obstruction Mask Shouldn’t occlude nostrils, pressure on eyes Chin Lift Pressure on submental tissues occludes airway as tongue is pushed up into palate. Jaw thrust – most effective manouvere 9/21/2018 IARNA 2010

LARYNGOSCOPY Straight blade picks up epiglottis Mobile larynx means cricoid pressure can considerably improve the view. Vocal cords angled – anterior commisure may hitch tracheal tube – rotate it. Most ET tubes are marked with black line to indicate how far to insert. 9/21/2018 IARNA 2010

Microlaryngoscopy Inhalational technique IV anaesthesia technique 9/21/2018 IARNA 2010

Common problems Laryngospasm UAO Laryngeal obstruction Foreign body Epiglottitis/Papillomatosis/Vocal cord palsy Foreign body Sub glottic oedema/ Tracheomalacia Mediastinal mass Difficult intubation 9/21/2018 IARNA 2010

Upper airway obstruction Laryngomalacia – commonest congenital stridor 9/21/2018 IARNA 2010

Laryngomalacia Presents 2 weeks Stridor feeding difficulties Gone by 18 – 24 months 9/21/2018 IARNA 2010

Laryngospasm BCH experience 210 cases over 6 years Inadequate depth of anaesthesia usual factor Commonest < 6 years and < 1 yr Experience of anaesthetist influenced occurence 9/21/2018 IARNA 2010

Laryngospasm - treatment CPAP & O2 successful in third of cases Deepen anaesthesia - Propofol – over 70% of cases. Muscle relaxant 9/21/2018 IARNA 2010

Laryngospasm - prevention Adequate depth of anaesthesia ALWAYS HAVE IV BEFORE LARYNGOSCOPY Spray cords with local if working on airway Remove LMA early and ET either anaesthetised or awake. 9/21/2018 IARNA 2010

Laryngeal obstruction Epiglottitis Papillomatosis Haemangioma Laryngeal web Vocal cord palsy 9/21/2018 IARNA 2010

Papillomatosis HPV 6 & 11 Repeated microdebriement Cidofovir ?? Don’t intubate. Discard circuit after single use. 9/21/2018 IARNA 2010

Haemangiomas Laser Tracheostomy Steroids B Blockers Propranolol Acetbutalol 9/21/2018 IARNA 2010

Vocal cord paralysis Idiopathic, neurological, iatrogenic, birth trauma. Stridor, feeding difficulties 70% resolve. 9/21/2018 IARNA 2010

Foreign Body 9/21/2018 IARNA 2010

FB – post removal 9/21/2018 IARNA 2010

Laryngeal Cleft 9/21/2018 IARNA 2010

Laryngeal Cleft – Grade 1 9/21/2018 IARNA 2010

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Difficult airway Difficult intubation Cant ventilate 0.08% healthy & 0.42% all children Anaesthesiology 2007;107:A1637 0.095% < 16 yrs & 0.24% < 1 yr Paediatr Anaesth 2004. Cant ventilate <0.02% difficult but never impossible. Anaesthesiology 2007;107:A1637 Adults 0.15% difficult to ventilate Anaesthesiology 2009 110:891 9/21/2018 IARNA 2010

Diff ventilation More common in less experienced hands Anatomical Functional Laryngospasm Light anaesthesia Inflated stomach Bronchospasm. 9/21/2018 IARNA 2010

Difficult intubation/ventilation Anticipate Have a plan A, plan B and C if necessary. Maintain oxygenation Tracheostomy DON’T PANIC!!! GET HELP 9/21/2018 IARNA 2010

ANTICIPATE Congenital Structural Inflammatory Neoplastic Cranio-facial abn – Pierre-Robin etc. Laryngotracheal – web, stenosis, malacia Structural foreign body, stenosis, burns, oedema, vascular. Inflammatory Croup, epiglottitis, papillomatosis, abscess Neoplastic Cystic hygroma, tumours. 9/21/2018 IARNA 2010

Assess – History Snoring Apnoea Stridor Blue Hoarse Inspiration (extrathoracic e.g laryngomalacia) Expiration (intrathoracic) Blue Hoarse Daytime somnolence? Previous anaesthetic? Preferred position sitting? 9/21/2018 IARNA 2010

Assess - physical Failure to thrive – sleep disordered breathing Caucasian v African children - UAO Dyspnoea Chest retractions Drooling saliva Weak cry Dysmorphic facies 9/21/2018 IARNA 2010

Additional Lung function tests – spirometry FEV1 Radiology AP & lateral of neck and thoracic inlet CT & MRI Awake Endoscopy Anatomy + dynamic views Sleep studies 9/21/2018 IARNA 2010

Anaesthesia Inhalational induction – technique of choice IV – occ used but in small doses so spontaneous respiration is maintained Always secure IV access before attempting intubation. Neuromuscular blockers best avoided Time !!! 9/21/2018 IARNA 2010

Difficult intubation Is airway secure? i.e oxygenation & ventilation Is position correct? Is roll present? Is it too big? Use cricoid pressure How long do I attempt it? – assistant role! How many attempts – avoid trauma Do I need to intubate? – wake up or tracheostomy? 9/21/2018 IARNA 2010

Laryngeal mask airway Definitive airway May be used to ventilate child As conduit for fibreoptic intubation Temporary airway until surgical airway secured 9/21/2018 IARNA 2010

Alternative laryngoscopes Mc Coy Macintosh Seward Paediatric video laryngoscope Storz & Glidescope May assist in intubation Some reports of benefit Early in their use 9/21/2018 IARNA 2010

Fibreoptic intubation Child must be anaesthetised, oxygenated and stable to allow time for intubation. ET in nostril or special mask. Topical anaesthesia 4% lidocaine Oral, via nasal ET tube, or via LMA. Try to maintain skills. 9/21/2018 IARNA 2010

Fibreoptic intubation oral, nasal. Load tube onto scope Nasoendoscopes 2.2 – 2.5 mm no suction should take any size tube. Bronchoscopes 2.8 – 4 mm. Can take size 3.5 ET tube. Have suction May use suction port to deliver local 9/21/2018 IARNA 2010

OLCHC Plan Inhalational induction & IV access Anaesthetic intubation Intubate with MLB setup (Parsons) Rigid bronchoscope & bougie Maintain airway with mask or LMA Tracheostomy 9/21/2018 IARNA 2010

Tracheostomy – when ? Cant intubate Can intubate but with much difficulty Extubation may cause problem 9/21/2018 IARNA 2010

Cant intubate, cant ventilate Very rare Needs structured protocol to manage 9/21/2018 IARNA 2010

Cricothyroidotomy complications Pneumothorax Surgical emphysema Vascular injury Haemorrhage Haematoma False passage Aspiration Pulmonary barotrauma Subglottic oedema Subglottic stenosis Oesophageal perforation Infection 9/21/2018 IARNA 2010

Cricothyroidotomy APLS/Books percutaneous needle or surgical cricothyroidotomy In practice – trachea may be only mm in diameter therefore cricothyroidotomy very difficult 9/21/2018 IARNA 2010

Principles for paediatric diff intubation Maintain oxygenation & ventilation Multiple and prolonged attempts at intubation cause morbidity – therefore limit to 4. Blind techniques have a high failure rate and cause trauma. Awaken patient and postpone surgery? 9/21/2018 IARNA 2010

Principles for paediatric cant intubate cant ventilate scenario Use 2 person technique to ventilate LMA – frequently rescues situation If above fail – proceed to surgical airway. 9/21/2018 IARNA 2010