Pediatric Airway Management

Pediatric Airway Management Margaret Winkler, MD Pediatric Critical Care University of Alabama at Birmingham The Pediatric Airway      Introduction Anatomy / Physiology Positioning Adjuncts Intubation Introduction Almost all pediatric “codes” are of respiratory origin Internal Data. B.C. Children’s Hospital, Vancouver. 1989. Pediatric Cardiopulmonary Arrests 10% 10% 1° Respiratory Shock 80% 1° Cardiac Age distribution of arrests 40 35 30 # Arrests 25 20 15 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Age (years) Arrive in ER in cardiac arrest (N = 80) Admit PICU (N=43) 54 % Mod Deficit (N=3) PVS at 12 mos (N=2) Dead at 12 mos (N=1) Died in ER (N=37) 46% Died in ICU (N=37) 46% Schindler M, et al. Outcome of out-of-hospital cardiac or respiratory arrest in children. N Engl J Med 1996;335:1473-1479. Anatomy Children are very different than adults !!! Anatomy : Nose • • Nose is responsible for 50% of total airway resistance at all ages Infant: blockage of nose = respiratory distress Anatomy : Tongue • • • Large Loss of tone with sleep, sedation, CNS dysfunction Frequent cause of upper airway obstruction Anatomy : Larynx • High position • Infant : C 1 • 6 months: C 3 • Adult: C 5-6 • Anterior position Children are different Anatomy : Larynx Narrowest point = cricoid cartilage in the child Anatomy : Epiglottis • • • Relatively large size in children Omega shaped Floppy – not much cartilage Physiology: Resistance Peripheral airways contribute to total airways resistance: Adult Child 20% 50% Physiology: Effect of Edema Poiseuille’s law R= 8nl  r4 If radius is halved, resistance increases 16fold Airway positioning for children <2yrs Airway Positioning “Sniffing Position” In the child older than 2 years Towel is placed under the head Airway adjuncts • • Nasal airway Oral airway Nasopharyngeal Airway Length: Nostril to Tragus Contraindications:  Basilar skull fracture  CSF leak  Coagulopathy Endotracheal tube as nasal airway A regular ETT can be cut and used as a nasal airway Adjuncts: Oral Airway Wrong size: Too Long Adjuncts: Oral Airway Wrong size: Too Short Adjuncts: Oral Airway Correct size Oral Airways Signs of Respiratory Distress • • • • • • • • Tachypnea Tachycardia Grunting Stridor Head bobbing Flaring Inability to lie down Agitation • • • • • • • • Retractions Access muscles Wheezing Sweating Prolonged expiration Pulsus paradoxus Apnea Cyanosis Impending Respiratory Failure • • • • • • Reduced air entry Severe work Cyanosis despite O2 Irregular breathing / apnea Altered Consciousness Diaphoresis Respiratory Failure • • Hypoxic respiratory failure Hypercarbic respiratory failure Hypoxemia Mechanism • • • • • Distinguishing Attribute •Low Inadequate inspiratory partial pressure of oxygen Global alveolar hypoventilation Right to left shunt V/Q mismatch Incomplete diffusion equilibrium barometric pressure or FIO2 •High PaCO2 •Little change with extra oxygen •Good response to O2 •Good response to O2 Incomplete diffusion equilibrium • • • • Thickened alveolocapillary membrane (true diffusion block) Abnormally low oxygenation of mixed venous blood Lung damage or destruction, resulting in reduced alveolar capillary volume Increased CO with reduced alveolar capillary transit time Intubation: Indications • • • • • • Failure to oxygenate Failure to remove CO2 Increased WOB Neuromuscular weakness CNS failure Cardiovascular failure Intubation • Larynx cephalad and anterior in children – Practitioner may need to be lower than patient and look up Cephalad and anterior Laryngoscope Blades Macintosh Miller Intubation Technique Better in younger children with a floppy epiglottis Straight Laryngoscope Blade – used to pick up the epiglottis Intubation Technique Better in older children who have a stiff epiglottis Curved Laryngoscope Blade – placed in the vallecula Intubation Age Newborn 3 mos 1 yr 2 yrs kg 3.5 6.0 10 12 ETT 3.5 3.5 4.0 4.5 Length (lip) 9 10 11 12 Children > 2 years: ETT size: Age/4 + 4 ETT depth (lip): Age/2 + 12 Technique: Intubation How far does it go in ? Deterioration after Intubation • • • • Displaced tube Obstructed tube Pneumothorax Equipment