Pediatric Airway Emergencies
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Pediatric Airway Emergencies Elliot Melendez, MD Pediatric Emergency Medicine and Critical Care Children’s Hospital, Boston Disclosures No financial disclosures No conflict of interest Outline Discussion of stridor Challenges of pediatric airway Rapid assessment for difficult airway Critical airway management strategies Highest Acuity Patients Precipitating Conditions Respiratory Circulatory Resp. Distress Shock Respiratory failure Cardiopulmonary Failure Cardiac Arrest Sudden Cardiac Highest Acuity Patients Precipitating Conditions Respiratory Circulatory Resp. Distress Shock Respiratory failure Cardiopulmonary Failure Cardiac Arrest Sudden Cardiac Highest Acuity Patients Precipitating Conditions Respiratory Circulatory Resp. Distress Shock Respiratory failure Cardiopulmonary Failure Cardiac Arrest Sudden Cardiac Survival Data Highest Acuity Patients Precipitating Conditions Respiratory Resp. Distress Circulatory Survival rates for resuscitation from: Sudden Cardiac Resp arrest: 43 – 82% Cardiac arrest 4 – 14 % Shock Respiratory failure Cardiopulmonary Failure Cardiac Arrest Early recognition and treatment of respiratory compromise can improve outcome. Case 6 month boy p/w fever and cough x 5 days Cough is described as barky, and non-productive Normal behavior, not irritable, decreased po’s Case VS: T 40.3, HR 150, RR 44, SaO2 95% on RA Chest: coarse breath sounds, but no wheezing. Inspiratory stridor at rest without increased work of breathing Remainder of exam unremarkable Case Decadron IM and racemic epinephrine neb were given with minimal improvement. While in ED, biphasic stridor at rest with severe retractions, becomes toxic appearing. Some mild improvement to repeat racemic epinephrine nebs Admitted to floor for observation Case Croup 6 mo to 6 years URI sxs Stridor +/- fever Could there be an alternative diagnosis? Stridor is the hallmark symptom associated with upper airway disease Rapid Assessment How Bad is it? If distress is severe Ie. stridor at rest, cyanosis, severe retractions, toxic appearing quickly examine and intervene If stridor is mild: Then obtain a more complete and accurate history develop a plan based on the differential diagnosis Stridor Croup Clinical diagnosis Routine radiographs of neck or chest not indicated Dexamethasone therapy of choice for airway edema If no stridor at rest, can send home Who do you need to work-up? Croup When stridor is atypical for croup: Fixed stridor or isolated exhalatory stridor. Poor/No response to inhaled racemic epinephrine and/or steroids Extremes of age Greater than age 6, less than 6 month Toxic appearing Persistently high fever. No viral prodrome, sudden onset Work-up Atypical Stridor Not all atypical stridor needs a work-up Admit and observe Physical Exam maneuvers Lateral and AP Neck CXR ENT consult Physical Exam Maneuvers Lay the infant Pass nasal catheter Laryngomalacia worse with laying flat to determine the patency Place in sniffing position and/or jaw thrust If the stridor lessens, obstruction may be at the level of the larynx or higher Atypical Stridor Heavy drooling High fever Refusing to move neck Retropharyngeal Abscess Typical presents 6-36 months Look at prevertebral space Complications include: Mediastinitis, pericarditis, airway obstruction Tip: Retropharyngeal swelling For C1-2 For C3-7 should be < ½ width of vertebral body should be < width of vertebral body False positives and negatives: False (+): Flexion, crying, +/expiration False (-): Parapharyngeal collection Radiographs in Atypical Stridor Other Findings Steeple’s sign Thumb sign Radio-opaque foreign bodies Mediastinal masses Congenital anomalies Steepling Analogies: Wine Bottles Bordeaux Burgundy Steepling Analogies: NYC Buildings Empire State Building Chrysler Building Steepling Analogies: NYC Buildings Empire State Building Chrysler Building Radiographs in Stridor Other Findings Steeple’s sign Thumb sign Epiglottitis Radio-opaque foreign bodies Mediastinal masses Congenital anomalies Radiographs in Stridor Other Findings Steeple’s sign Thumb sign Radio-opaque foreign bodies Mediastinal masses Congenital anomalies Radiographs in Stridor Other Findings Steeple’s sign Thumb sign Radio-opaque foreign bodies Mediastinal masses Congenital anomalies Radiographs in Stridor Other Findings Steeple’s sign Thumb sign Radio-opaque foreign bodies Mediastinal masses Congenital anomalies Radiographs in Stridor Other Findings • Steeple’s sign • Thumb sign • Radio-opaque foreign bodies • Mediastinal masses • Congenital anomalies Right Sided Aortic Arch Aberrant left subclavian artery gives rise to ductus arterious and compresses trachea Surgery involves clipping of ligamentous arterious Case Worsened distress in AM Taken to the OR and DL performed. Pus seen in trachea, intubated Culture grew Staph Aureus Started on Unasyn (pre-MRSA) and improved Bacterial Tracheitis Pathology H. influenzae B was most common prior to 1992 or in unimmunized immigrants Staph Aureus most common, usually superinfection. Other: GAS, pneumococcus, mycoplasma AP neck x-ray: may show “thumb print” sign subtle Patient Has Resp Compromise You decide airway needs to be secured….. Preparation? Equipment - SOAP ME Personnel Prepare Equipment S: Suction O: Oxygen and how to deliver Appropriate ETT, oral/nasal airway, stylets, laryngoscopes P: Pharmacology Nasal cannula, oxygen flow, masks and appropriate bag A: Airway Catheters (6 - 16 french) and Yankauer tips (two sizes) RSI meds ME: Monitoring equipment EtCO2 detector, stethescope, monitors Artificial Airway Oral Tip of mouth to corner of mandible Artificial Airway Nasal Nostril to tragus Appropriate Size is Key Correct size Incorrect size (Atlas of Airway Management, 2007) Endotracheal Tubes Age Size (Inner Diameter, mm) Premature 2.5 Term to 3 mo 3.0 3 to 7 mo 3.5 7 to 15 mo 4.0 15 to 24 mo 4.5 2 to 15 yr Internal diameter = [16 + age (yr)]/4 (round to the nearest 0.5 mm) (maximum 8.0) Depth = ETT x 3 (lip) Cuffed vs. Uncuffed? Prospective observational studies No difference in the incidence of post-extubation stridor between 95 children intubated with uncuffed and 93 with cuffed ET tubes Deakers, TW, Reynolds, G, Stretton, M, et al. Cuffed endotracheal tubes in pediatric intensive care. J Pediatr 1994;125:57. No difference in use racemic epi for postextubation subglottic edema between 387 children intubated with uncuffed and 210 with cuffed ET tubes Newth, CJ, Rachman, B, Patel, N, Hammer, J. The use of cuffed versus uncuffed endotracheal tubes in pediatric intensive care. J Pediatr 2004; 144:333. Cuffed vs. Uncuffed? Khine HH, et al - Anesthesiology 1997 Full-term newborns through 8 yr (n = 488) Cuffed tube sized by a new formula = (age/4) + 3 Uncuffed tube modified Cole's formula = (age/4) + 4 Conclusion Formula for cuffed tube selection is appropriate Advantages of cuffed endotracheal tubes Avoidance of repeated laryngoscopy Cuffed tubes may be used routinely during controlled ventilation in full-term newborns & children for anesthesia Cuffed vs. Uncuffed? Cuffed ET tubes may be placed by experienced intubators Except neonatal Size should be 0.5 – 1 mm smaller Cuffed ET tube preferred for those with: Severe lung disease High ventilator pressures Bronchospasm or chronic lung disease Preferred by critical care physicians Equipment: Blade and Tube Size Age Blade/Size Infant Miller 1 2 years old Miller 2 12 years old Miller/Mac 3 “Switch to a 2 at 2” Prepare Personnel Respiratory therapy, nurses, pharmacy Assignment of roles Watch monitor Administer meds Sellick maneuver, Pull lip Pass ETT, aAttaching EtCO2 PREPARATION What are the particular issues in pediatrics which can effect airway management? Pediatric Airway Issues Airway management has it challenges…. Anatomic Physiologic Relatively less experience One size does not fit all Anatomy Occiput Relatively larger occiput causes passive flexion of c-spine. Interferes with attempts to align the oral, pharyngeal, and tracheal axes for visualization Anatomy Alignment Oral axis Pharyngeal axis Laryngeal axis Anatomy Marx: Rosen's Emergency Medicine: Concepts and Clinical Practice, 6th ed., Copyright © 2006 Mosby, Inc. Anatomy Position of larynx In infants and children is more anterior and superior than adults More acute angle between the epiglottis and the glottic opening Anatomy Tongue Large compared to the size of the oral cavity Epiglottis Relatively large and floppy in infants Epiglottis covers more of the glottic aperture Physiologic: Edema Effects Poiseuille’s law Physiologic Considerations More rapid cardiopulmonary decline Increased risk of upper airway obstruction Prone to bradycardia Laryngeal stimulation and hypoxia Higher oxygen consumption Lower functional residual capacity Less oxygen reserve Physiologic differences: Clinical evidence (Patel et al., Can J Anaesth, 1994) Relatively Less Experience Adult Emergency Department Levitan, Acad Emerg Med, 2001 50,000 patients per year 500 airways/year Pediatric Emergency Department Children’s Hospital, Boston data 50,000 patients per year 50 airways/year Evaluating for the Difficult Airway Case 11 mo brought to ED after dad was feeding child with edamame Case Mother heard coughing and gagging on child monitor EMS called Evaluation and Management Evaluation Sudden onset Inspiratory stridor at rest No fever Clear lungs High suspicion for airway F.B. Management LEAVE HIM ALONE! No IV placement Remained in mother’s lap ENT called stat Recognition of Difficult Airway Suspected/Known Craniofacial anomolies Croup/Epiglottis Vascular malformations Foreign body Mediastinal mass Cervical/Thoracic abnormalities Facial/Oral Trauma Recognition of Difficult Airway Predictors - LEMON Look Evaluate 3-3-2 Short neck, large tongue, micrognathia 3 finger breadths of mouth opening 3 finger breadths submental to hyoid 2 finger breadths hyoid to thyroid Mallampati Obstruction Neck mobility Predict 100% success in Adults Not validated in pediatrics Predictors - LEMON Look Evaluate 3-3-2 Short neck, large tongue, micrognathia 3 finger breadths of mouth opening 2 finger breadths submental to hyoid (potential displacement area) 2 finger breadths hyoid to thyroid Mallampati Obstruction Neck mobility Historical Factors Small jaws Large tongues Congenital myopathies Pierre-Robin sequence, Crouzon Beckwith-Weiderman syndrome Infiltrative d/o’s – mucopolysaccharidosis Trisomy 21 Risk of malignant hyperthermia Duchene’s MD 25% Noonan’s syndrome >50% Historical Factors Small jaws Large tongues Congenital myopathies Pierre-Robin sequence, Crouzon Beckwith-Weiderman syndrome Infiltrative d/o’s – mucopolysaccharidosis Trisomy 21 Risk of malignant hyperthermia Duchene’s MD 25% Noonan’s syndrome >50% Historical Factors Small jaws Large tongues Congenital myopathies Pierre-Robin sequence, Crouzon Beckwith-Weiderman syndrome Infiltrative d/o’s – mucopolysaccharidosis Trisomy 21 Risk of malignant hyperthermia Duchene’s MD 25% Noonan’s syndrome >50% Known/Suspect Difficult Airway Management Easy! Call for help The difficult pediatric airway is best NOT managed by heroic or uncommonly used techniques Carefully assess and plan Children with chronic/congenital issues has typically been intubated in past check anesthesia records if time permits Anticipate difficulties and prepare suitable back-up plan Call ahead, or know how to reach quickly, the anesthesiologists and surgeon on-call Case Scenario Called to transport full term newborn with respiratory distress Intubated at OSH with 3.0 uncuffed ETT On team arrival, poor chest movement on high vent settings and audible air leak Decision to change ETT to 3.5 uncuffed Clinical Decision Making Options: Sedate, muscle relax Increase vent settings Direct laryngoscopy for tube position Reintubate with larger tube, and/or cuffed tube Goals of Larynoscopy What we want to see is this Goals of Laryngoscopy The problem is… …but we are here. Cords are here… Goals of Laryngoscopy The problem is… The aim is… To “see around the corner” • The goal of DL… • To get rid of the corner • To create straight line of sight Goal: Visualizing the Cords Aligning the 3 Axes Oral axis Pharyngeal axis Pharyngeal Oral Tracheal axis Tracheal Goal: Visualizing the Cords Aligning the 3 Axes Oral axis Pharyngeal axis Tracheal axis Case Course Under DL, visualized ETT through vocal cords, and removed. 3.5 uncuffed ETT passed easily through vocal cords Bag-ETT performed with no chest rise, and immediate desaturation Recurs x4 In between, easy bag-mask with chest rise Unrecognized Difficult Airway Management Are you able to mask ventilate and oxygenate? Difficult Intubation Interventions Upgrade intubator Bag mask until advanced airway interventions can be instituted Alternative modes Difficult Airway Difficult Mask Ventilation: inability to maintain SpO2 > 90% using 100% oxygen and BMV High risk Not only loss of airway, but risk of loss of vital signs Difficult Mask Difficult Mask after failed intubation Move quickly to alternative Immediate best intubator Immediate to alternative modes Fiberoptic, surgical airways time consumption Rarely done Technically difficult in peds Alternative: Laryngeal Mask Airway 1981 - Dr. Archie Brain Royal London Hospital Initially developed as a rescue tool Laryngeal Mask Airway LMA Size Patient Size 1 Neonate / Infants < 5 kg 1½ Infants 5-10 kg 2 Infants / Children 10-20 kg 2½ Children 20-30 kg 3 Children/Small adults 30-50 kg 4 Adults 50-70 kg 5 Large adult >70 kg LMA: Insertion Figure 42-10 Insertion of the laryngeal mask airway (LMA). A, The tip of the cuff is pressed upward against the hard palate by the index finger while the middle finger opens the mouth. B, The LMA is pressed backward in a smooth movement. Notice that the nondominant hand is used to extend the head. C, The LMA is advanced until definite resistance is felt. D, Before the index finger is removed, the nondominant hand presses down on the LMA to prevent dislodgment during removal of the index finger. The cuff is subsequently inflated, and outward movement of the tube is often observed during this inflation. (Courtesy of LMA North America, Inc., San Diego, CA.) Mgmt of the Critical Airway Can’t ventilate Can’t intubate LMA contraindication (massive orofacial trauma) or not working Cricothyrotomy < 5 years old 5 to 10 years old Needle cricothyrotomy and bag ventilation Needle cricothyrotomy and bag ventilation If oxygen saturation is inadequate: transtracheal jet ventilation regulated to low PSI > 10 years Operator preference Needle cricothyrotomy with TTJV or Surgical cricothyrotomy Percutaneous Transtracheal Ventilation Beneficial for children who cannot be “ventilated” by other route Experience level with this procedure is minimal Percutaneous Transtracheal Ventilation 3-5cc syringe: 1-2cc saline OR 12- or 14-gauge IV Summary Pediatric airway emergencies are common Stridor is the hallmark of an upper airway obstruction, thus emergency Potential for difficult airway is high in pediatrics Identify resources, anticipate problems Familarize yourself with alternative techniques Thank You!!! Questions??
