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Hamilton CME
Paediatric Respiratory Emergencies
Spring 2008
Paediatrics
Stages of development: Newborn / Neonate:Birth to 29 days Infancy: 1 month to 1 year Toddler: 1 – 3 years Pre-school: 3 - 5 years School child: 5 - 15 years Adolescent: 15 - 19 years
Respiratory System:
The respiratory system matures as the child gets older.
Newborns are usually nose breathers. This facilitates breathing while suckling.
Age: Range of normal / min. Rapid / min.
Newborn: 30-50 >60
Infancy: 20-30 >50
Toddler: 20-30 >40
Children: 15-20 >30
Given a Competent Primary Survey
Hands off approach. When examining a child, perform the most critical
assessment you need to do before the child starts to cry.
Take some history, visualize the child and decide which assessment you need to do first to confirm or rule out your suspicion.
Listen to MOM! ( ‘my baby doesn’t quite seem right’ )– A good mother will often make a better diagnosis
than a poor Doctor ( or Paramedic ).
Respiratory System
Infection:– Can cause a relative arterial hypoxemia.– Predisposed to disease because of size
& structure.– Small airways, poor muscle
development, can’t clear mucous well during infections.
Respiratory System
Respiratory Distress:Lower airway: – short trachea, bifurcation at 45o.– Airways close more easily.– Incomplete lung development until 8 years old.
Chest wall: – Muscles tire more easily.– Highly compliant, makes rib cage inefficient in producing an
increase in lung volume & allows for distortion under stress - retractions.
– Large stomach & liver encroach on respiratory effort.
Pneumonia
Introduction– Pneumonia is defined pathologically as an
inflammation of lower tract lung tissue. (1)
Pneumonia
Pneumonia
Pathophysiology– Defense mechanisms
• Macrophages• Antibodies• Lymphatic drainage
Pneumonia
Pathophysiology anatomic defenses may be d/t preceding
viral infection of upper respiratory tract.
Pneumonia
Pathophysiology– Acute inflammatory response
• Exudative fluid• Fibrin deposition• Leukocytes• Macrophages
Pneumonia
Clinical Features– Fever can increase an infant's respiratory
rate by 10 breaths/min for each degree centigrade of elevation. (1)
Pneumonia
Clinical Features– Adventitious breath sounds WOB– Grunting respirations– Abdominal distention
Signs of Respiratory Trouble:
Facial Signs Colour ( lips and circumoral ) Nasal flaring Neck Tracheal tugging Supraclavicular Retractions Chest Lower Sternal Retraction Intercostal and/or subcostal indrawing
Pneumonia
Typical– Acute onset– High-grade fever– Pleuritic chest pain– Productive cough– Bacterial pathogen
Atypical– Gradual onset– Low-grade fever– Non-productive cough– Viral pathogen
Pneumonia
Clinical Features– Infants frequently lack the classic symptoms
and present with a variety of nonspecific findings. (1)
Pneumonia
Clinical Features– More severe pneumonia is associated with
deterioration of the patient's mental status, the use of accessory muscles, and the presence of retractions, nasal flaring, splinting, and cyanosis. (1)
Asthma
Asthma
Pathophysiology– Classifications
• Extrinsic (IgE-mediated)• Intrinsic (infection-induced)• Mixed
Asthma
Pathophysiology– Two-stage process
1. Bronchoconstriction (early)
2. Mucosal edema & plugging (late)
Asthma
Pathophysiology– Bronchospasm, mucosal edema, and mucous
plugging cause variable and reversible airflow obstruction with subsequent air trapping and impaired oxygen exchange.(2)
Asthma
Pathophysiology– Inadequate alveolar ventilation
• Carbon dioxide retention• Respiratory acidosis• Respiratory failure
Asthma
Pathophysiology– The child with asthma is at higher risk of
respiratory failure d/t: compliance of rib cage
• Immature diaphragm
• Lung tissue lacks elastic recoil
• Airway walls are relatively thicker
Asthma
Evaluation– Treatment with inhaled β2-agonists should not
be withheld while the initial evaluation is in progress. (2)
Asthma
Evaluation– “silent” or “quiet” wheezer
• Prolonged expiratory phase• Extreme air trapping
Asthma
Evaluation– Tripod positioning– Nasal flaring– Polyphonic wheezes– Cyanosis– Insensible fluid losses– Pulsus paradoxus & JVD
Asthma
Evaluation– History
• Precipitating factors• Prescription medications• Hospitalizations• Intubations• Tracheostomies
Asthma
Evaluation– History
• Neonatal - prematurity, BPD, NICU?• Adolescents - substance abuse?• All ages - aspiration / choking?
Asthma
Treatment– β2-Receptors are widely distributed on
bronchial smooth muscle and airway epithelial cells. (2)
Asthma
Treatment– Salbutamol can be concurrently
administered to an intubated patient via MDI and ETT spacer device or a patient assisted with BVM and spacer device.
Asthma
Asthma
Asthma
Treatment– Most children presenting in status
asthmaticus will be dehydrated because of increased insensible losses. (2)
Asthma
Complications– Respiratory failure– Atelectasis – Pneumomediastinum– Pneumothorax
Bronchiolitis
Introduction– A clinical syndrome of wheezing, chest
retractions, and tachypnea in children younger than age 2 years. (2)
Bronchiolitis
Epidemiology– October thru May– Peak age of incidence is 2 months
Bronchiolitis
Pathophysiology– Respiratory syncytial virus (RSV) causes
50 to 70 percent of clinically significant bronchiolitis. (2)
Bronchiolitis
Pathophysiology– Mucous plugging
• Necrosis of respiratory epthelium• Destruction of ciliated epithelial cells
– Submucosal edema
Bronchiolitis
Clinical Features– 911 may be called because of wheezing,
increased respiratory symptoms, nasal congestion, and difficulty feeding. (2)
Bronchiolitis
Clinical Features– RSV-related apnea
• Infants at highest risk are younger than 6 weeks old
and have a history of prematurity, apnea of
prematurity, and low O2 saturation. (2)
Bronchiolitis
Treatment– Keep patient & environment calm– Oxygen therapy PRN– Fluid therapy PRN
Bronchiolitis
Treatment– A trial of bronchodilator therapy, is an
optional and reasonable treatment and can be aborted if the child fails to show a response. (2)
Bronchiolitis
Treatment– Epinephrine is an effective treatment for the
wheezing of bronchiolitis. (2)
Stridor
Introduction– Stridor is due to Venturi effects created by
somewhat linear airflow through a semi-collapsible tube, the airway. (3)
Stridor
Introduction– Supraglottic– Subglottic– Trachea– Primary bronchi
Stridor
Introduction– Expiratory stridor, or wheeze, is common in
distal airways, since intrathoracic pressure may become much greater than atmospheric pressure during expiration. (3)
Stridor
Introduction– Patients with marked variation in the
pattern of stridor should be considered to have a foreign body in the airway until proven otherwise. (3)
Epiglottitis
Clinical Features– Since the introduction of the
Haemophilus influenzae vaccine, the incidence and demographics of this disease have changed remarkably. (3)
Epiglottitis
Clinical Features– Abrupt onset– High-grade fever– Sore throat– Stridor– Dysphagia +/- drooling
Epiglottitis
Treatment– DO NOT attempt to visualize the airway
unless respiratory failure/arrest is imminent.
Epiglotittis
Swollen, horseshoe-shaped epiglottis of a child with epiglottitis
Same child with ETT in place.
Epiglotittis
Normal Paediatric trachea
Epiglottitis
Treatment– Should the child develop respiratory
fatigue or if airway obstruction or apnea occurs before the airway has been secured, bag-valve-mask ventilation can be effective. (3)
Croup
Introduction– aka laryngotracheobronchitis– Peak 1-2 y.o.– Late fall thru early winter child age = effect of airway edema
Croup
Radiograph of patient with Croup.
Croup
Clinical Features– Insidious onset– Barking cough– Stridor S&S @ night
Croup
Treatment– Croup is an upper airway infection made
worse by agitating the child. – Do not attempt to examine the throat.
Croup
Treatment– Do not attempt to initiate an IV unless it is
required for essential medications or fluid resuscitation.
Croup
Treatment– Nebulized epinephrine decreases airway
edema by vasoconstriction of the boggy mucosal vessels. (3)
References
1. Emergency Medicine: A Comprehensive Study Guide - 6th Ed•VIRAL & BACTERIAL PNEUMONIA IN CHILDREN - Kathleen Brown, Willie Gilford, Jr.
2. Emergency Medicine: A Comprehensive Study Guide - 6th Ed•PEDIATRIC ASTHMA AND BRONCHIOLITIS - Maybelle Kou, Thom Mayer
3. Emergency Medicine: A Comprehensive Study Guide - 6th Ed•UPPER RESPIRATORY EMERGENCIES - Randolph Cordle