DISORDERS OF THE RESPIRATORY SYSTEM PART 1 (based on T) Flashcards
Signs of difficulty of breathing
Alar flaring, Retractions (Intercostal, Subcostal, Supraclavicular), Nasal Flaring and Substernal/Subcostal Retractions in Infant
Normal lung sounds
Bronchovesicular, Bronchial, Vesicular, Tracheal
Abnormal lung sounds (Continuous)
Wheezing (High-pitched, polyphonic wheeze; Low-pitched, monophonic wheeze), Stridor
Abnormal lung sounds (Discontinuous)
Crackles (Coarse crackles, Fine crackles)
Why is it important to specify the preparation of paracetamol in a prescription?
Because the preparation determines the dosage computation
Paracetamol preparations (Drops)
Available in different formulations
Paracetamol preparations (Syrup)
100 mg/ml, 120 mg/5 ml, 250 mg/5 ml, 125 mg/5 ml (government institutions)
Paracetamol preparations (Tablet)
500 mg (for adults)
Paracetamol preparations (Suppository)
125 mg, 250 mg
Paracetamol preparations (Ampoule)
150 mg/ml
Formula for paracetamol dosage
Weight (kg) x dose (mg/kg) ÷ preparation (mg/ml) = ml
Therapeutic dose of paracetamol
10-20 mg/kg/dose, lower limit (10 mg/kg) is preferred
Paracetamol dosing frequency
Every 4 hours
Amoxicillin preparations (Drops)
100 mg/ml
Amoxicillin preparations (Suspension)
125 mg/5 ml, 250 mg/5 ml
Amoxicillin preparations (Capsule)
250 mg/capsule, 500 mg/capsule
Therapeutic dose of amoxicillin
30-50 mg/kg/dose (lower limit preferred to avoid diarrhea)
Amoxicillin dosing frequency
Every 8 hours (divide total daily dose into 3)
Organs in the upper respiratory tract
Nose, Nasal cavity, Mouth, Sinuses, Throat (Pharynx), Voice box (Larynx), Windpipe (Trachea)
Organs in the lower respiratory tract
Lungs, Large airways (Bronchi), Small airways (Bronchioles), Air sacs (Alveoli)
Common causes of acute rhinitis
Viral infections: Rhinovirus, RSV, Coronavirus, Coxsackie virus, Enterovirus, Human metapneumovirus, Influenza virus, Parainfluenza virus, Adenovirus
Transmission of upper respiratory tract infections
Inhalation of aerosols, Direct contact with contaminated surfaces
Pathogenesis of RSV, Influenza virus, Adenovirus
Trigger inflammatory response by direct mucosal invasion and disruption of nasal epithelium
Incubation period of common colds
1-3 days
Symptoms of acute rhinitis
Sore throat, Nasal congestion, Lump sensation when swallowing, Hyposmia, Cough, Conjunctivitis, Fatigue
Common physical exam findings in acute rhinitis
Swollen and erythematous nasal turbinates, Clear to opaque white or yellow-green nasal discharge
Common causes of acute pharyngitis
Viruses (Rhinovirus, Adenovirus, Coronavirus, Enterovirus, Metapneumovirus),
Bacteria (GABHS, Strep. pneumoniae, Group C, Mycoplasma, C. diphtheria, N. gonorrhoeae)
Most common bacterial cause of streptococcal pharyngitis
Group A Beta-Hemolytic Streptococcus (GABHS)
Complications of streptococcal pharyngitis
Acute rheumatic fever,
Rheumatic heart disease,
Acute post-strep glomerulonephritis
Common bacterial pathogens of acute sinusitis
Streptococcus pneumoniae,
Moraxella catarrhalis
Non-typeable Haemophilus influenzae,
Complications of acute sinusitis
Brain abscess, Meningitis, Orbital cellulitis, Osteomyelitis
Pathogenesis of acute otitis media
Eustachian tube dysfunction leading to fluid accumulation in the middle ear, Nasopharyngeal reflux
Common bacterial pathogens of acute otitis media
Streptococcus pneumoniae,
Moraxella catarrhalis
Non-typeable Haemophilus influenzae
Why is acute otitis media more common in children?
Their eustachian tubes are shorter, more horizontal, and have a smaller diameter, making drainage less effective
Common treatments for viral pharyngitis
Warm saline gargle, Antipyretics, Anesthetic spray, Lozenges
First-line antibiotic treatment for streptococcal pharyngitis
Penicillin (DOC), Amoxicillin
Indications for tonsillectomy
Severe and recurrent pharyngitis (>7 episodes in previous year or >5 in each of the previous 2 years)
Common treatments for acute sinusitis
Amoxicillin (40 mg/kg/day for 10-14 days), Topical decongestants, Antihistamines, Saline wash
Preventive measures for upper respiratory infections
Influenza vaccination, Good hygiene, Proper waste disposal, Boosting immune system
What is the most common infectious cause of upper airway obstruction in infants and young children?
Viral croup (Laryngotracheobronchitis).
At what age does viral croup peak?
18-24 months.
How is viral croup transmitted?
Via aerosol droplets or direct contact with contaminated waste products.
What are the common etiologic agents of viral croup?
Parainfluenza viruses 1 and 3, Influenza A and B, RSV, Rhinovirus, Adenovirus, Measles Virus.
What are the key signs and symptoms of viral croup?
Low-grade fever, coryza, dry brassy (barking) cough, hoarse cry, and inspiratory stridor.
Why do symptoms of viral croup worsen at night?
Due to increased airway inflammation and secretions when lying down.
What radiographic finding is characteristic of viral croup?
Steeple sign on AP soft tissue neck radiograph.
What is the general management for viral croup?
Supportive care, hydration, antipyretics, cool mist, racemic epinephrine, steroids (nebulized budesonide or oral dexamethasone), and oxygen if needed.
Is antibiotic therapy beneficial in viral croup?
No, unless a secondary bacterial infection is suspected.
What infection is considered a true medical emergency and involves bacterial infection of the supraglottic structures?
Epiglottitis.
What are the most commonly implicated bacteria in epiglottitis?
Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Moraxella catarrhalis.
What are the hallmark signs and symptoms of epiglottitis?
High fever, severe throat pain, muffled voice, rapid symptom progression, drooling, respiratory distress, and tripod positioning.
What is the classic radiographic finding in epiglottitis?
Thumb sign on lateral neck radiograph.
What is the immediate management for epiglottitis?
Oxygen, preventive endotracheal intubation, or tracheostomy if necessary.
What antibiotics are used for epiglottitis?
Ceftriaxone, cefotaxime, chloramphenicol, or ampicillin.
What vaccine has significantly reduced cases of epiglottitis?
HiB vaccine (Haemophilus influenzae type B vaccine).
What bacterial infection of the trachea is often associated with viral upper respiratory infections and is potentially life-threatening?
Bacterial tracheitis (Membranous LTB, Pseudomembrane Croup).
What are the most common causative pathogens of bacterial tracheitis?
Staphylococcus aureus, Haemophilus influenzae type B, Moraxella catarrhalis.
What are the characteristic symptoms of bacterial tracheitis?
Mild fever, brassy cough, inspiratory stridor, increasing mucopurulent respiratory secretions, progressive respiratory obstruction.
What is the characteristic radiographic finding in bacterial tracheitis?
Ragged tracheal air column on lateral neck radiograph.
What is the treatment for bacterial tracheitis?
Endotracheal intubation, mechanical ventilation, humidification, IV broad-spectrum antibiotics.
What are possible complications of bacterial tracheitis?
Pneumonia, pneumothorax, hypoxic ischemic encephalopathy (HIE), septicemia, toxic shock syndrome (TSS), acute respiratory distress syndrome (ARDS).
What bacterial infection is caused by toxigenic Corynebacterium diphtheriae and is highly contagious?
Diphtheric laryngitis.
What are the hallmark symptoms of diphtheric laryngitis?
Fever, sore throat, fetor oris (bad breath), membranous pharyngitis, cervical lymphadenitis, bull neck appearance.
What is the characteristic radiographic finding in diphtheric laryngitis?
Widened prevertebral space or gas in the retropharyngeal space.
What is the treatment for diphtheric laryngitis?
Isolation, diphtheria antitoxin, antibiotics (erythromycin or penicillin), ventilatory support.
What are the possible complications of diphtheric laryngitis?
Toxin-mediated myocarditis, neuritis, pneumonia.
What life-threatening deep neck space infection can cause airway obstruction and mediastinal extension?
Retropharyngeal abscess.
What is the most common age group affected by retropharyngeal abscess?
Children under 6 years old.
What are the key symptoms of retropharyngeal abscess?
Fever, sore throat, dysphagia, odynophagia, neck pain, torticollis, a bulge in the retropharynx.
What is the first-line imaging study for suspected retropharyngeal abscess?
Soft tissue neck radiograph.
What is the characteristic radiographic finding in retropharyngeal abscess?
Widened prevertebral space or gas in the retropharyngeal space.
What is the primary treatment for retropharyngeal abscess?
Oxygen, IV antibiotics (3rd gen cephalosporin + ampicillin-sulbactam or clindamycin), surgical drainage if airway compromised.
What serious complications can arise from a retropharyngeal abscess?
Airway obstruction, sepsis, mediastinitis, jugular vein thrombosis, carotid artery erosion.
What infection is characterized by a collection of pus around the tonsils and is a complication of tonsillitis?
Peritonsillar abscess (Quinsy).
What is the most common causative organism of peritonsillar abscess?
Streptococcus pyogenes.
What are the key symptoms of peritonsillar abscess?
Fever, worsening unilateral sore throat, difficulty swallowing, halitosis, trismus, referred ear pain.
What are the physical exam findings in peritonsillar abscess?
Bulging, hyperemic, and edematous tonsil pushing the uvula towards the opposite side.
What is the treatment for peritonsillar abscess?
IV antibiotics (penicillin or clindamycin if allergic), surgical drainage, tonsillectomy if recurrent.
What is the key distinguishing factor between viral and bacterial bronchitis?
(VR-BC) we are busy
Viral bronchitis typically presents with rhonchi,
while bacterial bronchitis presents with crackles and elevated CRP.
What is the most common cause of bronchiolitis in young infants?
Respiratory Syncytial Virus (RSV).
What are the key symptoms of bronchiolitis?
Tachypnea, chest retractions, inspiratory crackles, expiratory wheezing, poor feeding, fever.
What is the preferred management for mild bronchiolitis?
Nasal suction, frequent small feeds, IV or nasogastric fluids, hypertonic saline.
What is the preferred management for moderate to severe bronchiolitis?
Oxygen therapy, close monitoring for respiratory failure, supportive care.
What is the key differentiating factor between pneumonia and bronchitis?
Pneumonia presents with focal lung findings (e.g., consolidation), while bronchitis presents with diffuse rhonchi or wheezes.
