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