bronchiolitis and bronchitis

BRONCHITIS &

BRONCHIOLITISQPT20303

Dr. Mohanad

Definition Acute bronchitis is acute infection of the

bronchial mucosa, without obstruction

ETIOLOGY:• Viral infection: 90% of cases• Respiratory Syncytial viruses –

parainfluenza, adenoviruses,• Bacteria Rarely; pneumococci, H.influenzae,

staphylococi and streptococci.

Clinical manifestation• Dry, hacking, unproductive cough • within 4-5 days the cough becomes productive• Sputum production (clear, yellow, green, or even blood-

tinged)• afebrile patient or low grade fever• Sore throat• Runny or stuffy nose• Headache• Muscle aches• Extreme fatigue• auscultation – rough high pitched rhonchi

Treatment Infants pulmonary drainage is facilitated by

frequent shifts in position Keep well hydrated, humidified air if possible Nasopharyngeal lavage with isotonic solution

(normal saline or Ringer lactate) Treat fever: Paracetamol > 38, 5 30 mg/kg/d: 4

doses Or buprofen 200 mg No antibiotics, antihistamines Expectorants in irritating and paroxysmal

coughing: Bromhexin (suspension, tabl.) , Ambroxol, Stoptussin (drops)

Evaluation of patients

Onset of dyspnea: stridor, wheezing Onset of general danger signs: convulsions

or abnormally sleepy Not able to drink, stopped feeding keel Patient don’t improve better after 5 days

Refer to hospital

Presence of general danger signs Fever > 39°C resistant to antipyretic

treatment Acute respiratory distress and cardiac failure Chronic cough > 30 days duration Hemoptysis

Acute Bronchiolitis Lower respiratory tract infection Common cause of illness in young children Common cause of hospitalization in young

children Associated with chronic respiratory

symptoms in adulthood May be associated with significant morbidity

or mortality

DIAGNOSIS Acute infectious inflammation of the

bronchioles resulting in wheezing and airways obstruction in children less than 2 years old

MICROBIOLOGYTypically caused by viruses

RSV-most common (50%)ParainfluenzaHuman MetapneumovirusInfluenzaRhinovirusCoronavirusHuman bocavirus

Occasionally associated with Mycoplasma pneumonia infection

Respiratory Syncytial Virus

• Ubiquitous throughout the world• Seasonal outbreaks

– Temperate Northern hemisphere: November to April, peak January or February

– Temperate Southern hemisphere: May to September, peak May, June or July

– Tropical Climates: rainy season

Parainfluenza

• Usually type 3, but may also be caused by types 1 or 2

• Epidemics in the early spring and fall

Influenza

• Very similar to RSV or Parainfluenza in symptoms

• Seasonal with similar distribution to RSV

• Usually epidemic in the Northern hemisphere January through April

Epidemiology

Typically less than 2 years with peak incidence 2 to 6 months

May still cause disease up to 5 years Leading cause of hospitalizations in infants

and young children Accounts for 60% of all lower respiratory

tract illness in the first year of life

Risk Factors of Severity Prematurity Low birth weight Age less than 6-12 weeks Chronic pulmonary disease Hemodynamically significant cardiac disease Immunodeficiency Neurologic disease Anatomical defects of the airways

Environmental Risk Factors

• Older siblings• Concurrent birth siblings• Native American heritage• Passive smoke exposure• Household crowding• Child care attendance• High altitude

Pathogenesis Viruses penetrate terminal bronchiolar cells--directly

damaging and inflaming Pathologic changes begin 18-24 hours after infection

Bronchiolar cell necrosis, ciliary disruption, peribronchial lymphocytic infiltration

Edema, excessive mucus, Sloughed epithelium lead to airway obstruction and

atelectasis Bronchiolar obstruction during expiration/ Air trapping and

over inflation Hypoxemia hypercapnia (CO2 retention, PaCO2>45mmHg,

PaO2 <90mmHg)

Clinical ManifestationsRespiratory signs

• Disease starting with signs of acute viral nasopharyngitis.

• Severe tachypnea >70-80 breaths/min• Spasmoid cough• Chest in drawing, intercostal, subcostal and xyphoid

retractions• Expiratory dyspnea, gasping, emphysematous chest,

on percussion – hyperresonance, very loud intensity• Diminished breath sound• Crepitations, Rhonchi, wheezing• Respiratory distress – dyspnea cyanosis

General signs

Fever (38-39°C) Febrile convulsions Vomiting, less appetite, dehydration Cyanosis, acrocyanosis Tachycardia, toxic myocard Diver and spleen below the costal margins

– result of depression of diaphragm in over inflation of lungs

EXAM

Tachypnea 80-100 in infants 30-60 in older children

Prolonged expiratory phase, rhonchi, wheezes and crackles throughout

Possible dehydration Possible conjunctivitis or otitis media Possible cyanosis or apnea

Diagnosis Clinical diagnosis based on history and

physical exam Supported by CXR: hyperinflation,

flattened diaphragms, air bronchograms, peribronchial cuffing, patchy infiltrates, atelectasis

Course Depends on co-morbidities Usually self-limited Symptoms may last for weeks but generally

back to baseline by 28 days In infants > 6 months, average hospitalization

stays are 3-4 days, symptoms improve over 2-5 days but wheezing often persists for over a week

Disruption in feeding and sleeping patterns may persist for 2-4 weeks

Hospitalization

• Children with severe disease• Toxic with poor feeding, lethargy,

dehydration• Moderate to severe respiratory distress

(RR > 70, dyspnea, cyanosis)• Apnea• Hypoxemia• Parent unable to care for child at home

TreatmentSupportive Care

Keep young infant to intensive care unite Humidified oxygen relieve hypoxemia• Antibiotics in secondary bacterial pneumonia Bronchodilating drugs – Salbutamol, Atrovent,

Terbutalin Antipyretics Oral intake and parenteral fluids to combat

dehydration Local corticosteroids: Beclometazon, Budesonid,

fluticazon

Respiratory Support

Oxygen to maintain saturations above 90-92%

Keep saturations higher in the presence of fever, acidosis, hemoglobinopathies

Wean carefully in children with heart disease, chronic lung disease, prematurity

Mechanical ventilation for pCO2 > 55 or apnea

Complications

Highest in high-risk childrenApnea

Most in youngest children or those with previous apnea

Respiratory failureAround 15% overall

Secondary bacterial infectionUncommon, about 1%, most in children requiring

intubation