Predicting the Pediatric Difficult Airway Kuwait 2014 Maria Matuszczak M.D. Division Chief Pediatric Anesthesia Department of Anesthesiology UT Houston to Disclose Objectives • Incidence of pediatric difficult airway • Anatomical and physiological differences of the pediatric airway • Indicators of a pediatric difficult airway • Embryology of the airway • Evaluating the difficult pediatric airway Ultimate Goal of Predicting the Difficult Airway Oxygenation Ventilation Predicting the difficult laryngoscopic intubation: are we on the right track? Editorial ; M. Murphy et al. CAN J ANESTH 2005,52:3;231-35 Airway and respiratory complications most common causes of anesthesia related morbidity Frequently occur in healthy children Failure to perform an adequate evaluation of the airway can lead to catastrophic outcome An update on pediatric anesthesia liability: closed claim analysis. N.Jimenez et al. Anesth Analg 2007;104(1):147-53 Laryngospasm, failure to ventilate, failure to intubate Anesthesia-related Cardiac Arrest in Children Initial Findings of the Pediatric Perioperative Cardiac Arrest (POCA)Registry Jeffrey P. Morray, M.D., Anesthesiology 2000,93:6-14 (20% of cardiac arrest du to respiratory events in healthy children) 20% Perioperative cardiac arrest and its mortality in children. A 9-year survey in a Brazilian tertiary teaching hospital Leandro Gobbo Braz M.D.,Pediatr Anesth 2006,16:860-66 (71.5% of cardiac arrest du to respiratory events) 71.5% Paediatric perioperative cardiac arrest and its mortality: database of a 60-month period from a tertiary care paediatric center Neerja Bharti,M.D., Eur J Anaesth 2009,96(5):490-5 (56% of cardiac arrest du to respiratory events) 56% Cardiac arrest in anesthetized children: recent advances and challenges for the future Jeffrey P. Morray, M.D., Pediatr Anesth 2011,21:722-29 (decrease of cardiac arrest, but not for <1 year of age, risk /age) Critical incidents and mortality reporting in pediatric anesthesia: the Australian experience Review of critical events Phiilip Ragg MD, Pediatr Anesth 2011,21:754-57 (WebAIRS: Respiratory and Airway critical events 21% , top of a 9 category list) Major Complications of airway management in the UK, NAP4 T.M.Cook et al. Br J Anaesth 2011, 106(5) 617-31 and 632-42 ( ten events in children < 10-yr, 5 infants, 3 deaths) Pediatric difficult airway registry Predicting the difficult laryngoscopic intubation: are we on the right track? Editorial ; M. Murphy et al. CAN J ANESTH 2005,52:3;231-35 1. 2. 3. 4. 1. 2. 3. 4. able to oxygenate via bag mask ventilation able to ventilate via SGD able to intubate able to secure a surgical airway Different Assessment in Different Situations Planned surgery Emergency department Code on the floor Antenatal The pediatric patient Most often not cooperative for evaluation “Awake” fiberoptic intubation ??? Deep sedation or GA often needed to proceed Evaluation of laryngoscopic views and related influencing factors in a pediatric population Asadollah Mirghassemi, M.D. Pediatr Anesth 2011; 21: 663-667 • • • • • • • Cross-sectional study, Iran 511 consecutive pediatric patients requiring ETT No known airway abnormality Age 0.5-13 years old, mean age 18 month Distance nose to upper lip, lower lip to mentum, ear tragus to mouth horizontal length of mandible thyromental distance, were measured Cormack& Lehane classification Results: difficult laryngoscopy, 16.4% in neonates 2.6% in >1 months - <5 years of age 0% in > 5 years of age distance lower lip to mentum, and ear tragus to mouth were associated with difficult intubation, but no cut off COPUR way score • C = Chin. • O = Oral opening. • P = Previous Intubations, Past History. • U = Uvula (Mallampati Score). • R = Range. Modifiers: mucpolysaccaridoses, morbid obesity, ―buck teeth‖, large tongue Anatomic differences between pediatric and adult airways Large head and prominent occiput Hypertrophied lymphoid tissue Long epiglottis The pediatric airway W.L. McNiece, S.F. Dierdorf, Semin Ped Surg 2004;13(3): 152-65 Nose breather Small nasal passage Large tongue Larynx more anterior, cephalad, located at C2-3 instead of C4-5 Small and short trachea Pediatric airway is highly compliant Cartilaginous support less developed Increased susceptibility to dynamic airway collapse Laryngeal structures more pliable, less rigid By the age of 8, airway similar to adult airway Respiratory physiologic differences between children and adults • • • • • respiratory rate chest wall compliance lung elastic recoil ( lung compliance) functional residual capacity rate of oxygen consumption Findings that predict the presence of a difficult airway in children Limited mouth opening, small mouth Large tongue, lingual tonsils Prominent central incisor, Mandibular hypoplasia Findings that predict the presence of a difficult airway in children Laryngeal edema (infection, inhalation injury) Hemangioma of the lip Facial or hemi-facial anomalies Malformation of the ear Findings that predict the presence of a difficult airway in children Mandibular, mid-face, and facial trauma Cervical spine immobility (immobilization, trauma, congenital malformation) Short neck, obesity, Obstructive sleep apnea Findings that predict the presence of a difficult airway in children Congenital hydrocephalus Abscess, Tracheal stenosis Tumor/ Foreign body Metabolic and Dysmorphic Syndromes Impressive list of syndromes associated with difficult airway: 4p-, 5p- ( cri du chat), 9p-, 11q-, 13q-syndrome, Achondro-gensis, -plasia, Apert, Arnold-Chiari, Arthrogryposis, Beckwith-Wiedemann, c-Syndrome, Carpenter, CHARGE, Cockayne, Cornelia de Lange, Crouzon, DiGeorge, Down, Dutch-Kentucky, Dwarfism, Epidermolysis Bullosa, Fabry Disease, Farber Disease, Fibrodysplasia Ossificans Progressiva, Fraser Syndrome, FreemanSheldon, FrontometaphysealDysplasia, Fryns, Goldenhar, Goltz, Gorham, Hajdu-Cheney, Hallermann-Streiff, Holoprosencephaly Sequence, Hunter (Mucopolysaccharidosis II), Hurler (MucopolysaccharidosisIH), Hurler-Scheie (Mucopolysaccharidosis I H/S), I-Cell Disease, Ichthyosis, Johanson-Blizzard, Juvenile Hyaline Fibromatosis, Kippel-Feil Sequence, Kniest, Larsen, Lipoid Proteinosis,Maroteaux-Lamy, Marshall-Smith, Meckel-Gruber, MelkerssonRosenthal, Menkes-Kinky-Hair, Metaphyseal Chondrodysplasia Jansen, Moebius, Morquio, Nager, Nemaline Rod Myopathy, Neurofibromatosis, Noonan, Opitz, Osteogenesis Imperfecta, Pfeiffer, Pierre-Robin, Pompe Disease, Popliteal Pterygium, Potter, Proteus, ……………………… Just to name some of them Difficult intubation in paediatrics. F. Frei et al. Paediatr Anaesth 1996;6:251-63 Nager Treacher Collins Embryology of the pediatric airway Branchial Arches 1. future mandible, middle ear bones, malleus, incus 2. stapes, styloid process and ligament, portion of hyoid bone 3. and 4. inferior portion of hyoid and thyroid cartilage Branchial Pouches 1. Auditory tube and middle ear cavity 2. Part of tonsillar fossa, lymphoid tissue 3. and 4. parathyroid and thymus Branchial Clefts 1. External ear Anatomy and assessment of the pediatric airway. L. Adewale , Pediatr Anesth 2009; 19(s.1):1-8 1. able to oxygenate via bag mask ventilation 2. able to ventilate via SGD 3. able to intubate 4. able to secure a surgical airway Predicting the difficult laryngoscopic intubation: are we on the right track? M. Murphy et al. CAN J ANESTH 2005,52:3;231-35 able to oxygenate via bag mask ventilation • • • • • • • Medical history ! Obesity/ OSA/day time fatigue, Noisy breathing/stridor/phonation/feeding Upper airway infection/cough/fever Auscultation Normal facies, lateral view Tumor, abscess, trauma able to ventilate via SGD • • • • • Medical history Mouth opening Normal facies Neck mobility teeth able to intubate • • • • • • • • • Medical history Obesity Noisy breathing Stridor Mouth opening Teeth Neck mobility Normal facies, especially lateral view Thyreo-mental distance in older children Ischemic subglottic damage following a short-time intubation. Marta Joao Silvaa et al. European Journal of Emergency Medicine 2008, Vol 15 ( 6) able to secure a surgical airway • • • • Neck anatomy/mobility Palpate cricoid membrane in older children Have ENT/surgeon available Have ultrasound available Difficult Airway Evaluation ASA difficult airway algorithm Imaging of the Airway and other exams CT MRI US Lung function tests ABG Sleep studies Endoscopy Anesthetic management of lingual thyroglossal duct cyst in an infant with stridor. H.V.Lauro et al. Abstract presented at IARS meeting , Vancouver 2011 Use of Sonography for Airway Assessment An Observational Study Mandeep Singh,M.D., J Ultrasound Med 2010;29:79-85 Prediction of Pediatric Endotracheal Tube Size by Ultrasonography M. Shibasakiet al.,Anesthesiology 2010; 113(4) ; 819-24 Assessment in the emergency situation Need to be fast No time to come back another day Assessment in the emergency situation Respiratory distress is 4th most common chief complaint in children presenting to the emergency department. Peak age of respiratory distress is under 2years of age, an age at which the airway is significantly different from the adult. Assessment in the emergency situation • • • • • • • • Appearance of child Work of breathing Agitation Noisy breathing/stridor/voice/cry Body position Normal facies Neck mobility Drooling Predicting the fetal difficult airway Antenatally diagnosed congenital airway obstruction Important information from Fetal MRI Exit procedure with multidisciplinary management If undiagnosed: potential for fatal outcome Four Cases of Congenital Airway Obstruction: Optimizing Perinatal management H.McDevitt, M.D., Acta Paediatr. 2007;96(10):1542-5 Conclusion Optimal outcomes with pediatric airway management require a thorough understanding of the physiologic, and anatomic differences between children and adults. Additionally difficult airway recognition, good preparation, and familiarity with back-up plans for airway management are essential. Questions maria.matuszczak@uth.tmc.edu