Pulm Mop-Up Flashcards
What kind of virus is Respiratory Syncytial Virus?
Medium-sized membrane-bound RNA virus
RSV causes…
acute respiratory tract disease in all ages
What population is RSV most significant in?
Most clinically significant in infants and young children
RSV in adults vs. children
- adults – Upper Respiratory Infections
- infants and children – Upper and Lower RT infxs
Where does mucus build-up in RSV?
small airways
RSV incubation
2–8 days
RSV detection and shedding
- virus is detected in secretions 4 days prior to clinical sxs
- typically shedding of infectious virions is 3–8 days (can be as long as 3–4 weeks in immunocompromised)
RSV transmission
- direct contact of nasopharyngeal or ocular mucosa with infected secretions
- nosocomial spread can occur because the virus can survive on surfaces and hands for several hours
RSV peak incidence
first 2 years of life (20–30% of infected infants develop lower respiratory tract disease)
Initial vs. subsequent RSV infections
Subsequent is milder
Those at greatest risk for severe RSV infection
- children < 1 year of age (especially those < 6 months of age)
- children born prematurely (< 35 weeks gestation)
- children with underlying cardiopulmonary disease (e.g., chronic lung disease of prematurity, congenital heart disease)
- Those with primary immune deficits
- Patients on immunosuppressive medications
Is there a RSV vaccine?
No - but there is prophylaxis
RSV prophylaxis
Synagis
- Very hard to actually get insurance to pay
- Reserved for high risk patients
(e. g. premie of 32 weeks born in April will start it immediately)
RSV clinical manifestations Infants/Young Children
Rhinorrhea Low-grade fever Mild systemic symptoms Cough Wheeze
*Gradual recovery over 1 – 2 weeks
RSV diagnosis
- Rapid diagnostic antigen assays from nasopharyngeal specimens are used for RSV detection, usually with a sensitivity of 80–90%
- Because concurrent serious bacterial infections are not common, complete blood counts or blood cultures are not indicated
When do you xray a child with RSV?
Those who likely have a secondary bacterial infection..
What is acute epiglottitis?
Acute, rapidly progressive form of cellulitis of the epiglottis and adjacent structures
- -H. influenzae type b (Hib)
- -Vaccine decreased incidence by > 90% in children
What sign do you see on film for acute epiglottitis?
Thumbprint sign
What is bronchiectasis?
Dilated airway with thick phlegm around it - can be from infection of inflammation - and chronic, productive cough.
Bronchiectasis classifications
- cystic fibrosis
2. non-cystic fibrosis
Bronchiectasis characteristics
- Most common in the 6th decade of life (age 50)
- Females > Males
- Decreased incidence in the US due to childhood vaccines against Pertussis and effective txmt of childhood respiratory infx w/abx
Bronchiectasis vicious circle hypothesis
- -Transmural infection, generally by bacterial organisms, causes inflammation and obstruction of airways.
- -Damaged airways and dysfunctional cilia foster bacterial colonization, which leads to further inflammation and obstruction
Bronchiectasis physical exam
- Chronic cough (90%)
- Sputum: may be copious and purulent (90%)
- Rhinosinusitis (60–70%)
- Fatigue: may be a dominant symptom (70%)
- Dyspnea (75%)
- Chest pain: may be pleuritic (20–30%)
- Hemoptysis (20–30%)
- Wheezing (20%)
- Bibasilar crackles (60%)
- Rhonchi (44%)
- Digital clubbing (3%)
Bronchiectasis diff dx
- CF
- Chronic obstructive pulmonary disease
- Asthma
- Chronic bronchitis
- Pulmonary TB
- ABPA (Allergic bronchopulmonary aspergillosis)
Bronchiectasis tests & interpretation
Spirometry
- -Moderate airflow obstruction and hyperresponsive airways
- -Forced expiratory volume in the 1st second of expiration (FEV1): < 80% predicted and FEV1/FVC < 0.7
Bronchiectasis tests & interpretation
Sputum culture
- -H. influenzae, nontypeable form (42%)
- -P. aeruginosa (18%)
- -Cultures may also be positive for Streptococcus pneumoniae, Moraxella catarrhalis, MAC, and Aspergillus.
- -Of all isolates, 30–40% will show no growth
What are the special tests for bronchiectasis?
- Sweat test for CF
- Purified protein derivative (PPD) test for TB
- Skin test for Aspergillus
- HIV screen (immunocompromised component)
What are the special tests for bronchiectasis?
- Serum immunoglobulins to test for humoral immunodeficiency
- Protein electrophoresis to test for α1-antitrypsin deficiency
- Barium swallow to look for abnormalities of deglutition, achalasia, esophageal hypomotility
- pH probe to characterize reflux
- Screening tests for rheumatologic diseases
What would you see on bronchiectasis chest radiograph?
Nonspecific; increased lung markings or may appear normal
What is the most important bronchiectasis diagnostic tool?
CT
What do you see on bronchiectasis CT?
Bronchi are dilated and do not taper, resulting in “tram track sign”; parallel opacities seen on scan.
Varicose constrictions and balloon cysts may be seen.
Focal vs. upper lobe bronchiectasis considerations.
- For focal bronchiectasis, rule out endobronchial obstruction.
- For exclusively upper lobe bronchiectasis, consider CF and ABPA.
Qualifications for acute exacerbation (bronchiectasis)
- requires 4 out of 9
- change in sputum production – increase
- increased dyspnea
- increased cough
- fever
- increased wheezing
- malaise, fatigue, lethargy
- reduced pulmonary function
- radiographic changes
- changes in chest sounds
Treatment of chronic bronchiectasis
- maintain hydration
- frequent exacerbations may be treated with prolonged and aerosolized antibiotics
- role of mucolytics, antiinflammatory agents, and bronchodilators is still unclear
First line acute exacerbation (bronchiectasis)
- Antibiotics: guided by sputum culture and sensitivity
- Bronchodilators: chronic use of β2-agonists (e.g., albuterol) reverses airflow obstruction.
- Inhaled corticosteroids: insufficient evidence exists to recommend use of inhaled steroids with stable bronchiectasis
What sign is on CT for bronchiectasis?
Cylindrical bronchiectasis, CT
“signet ring” sign
What is hyaline membrane disease?
AKA Surfactant Deficiency
- 93% incidence in infants born at or before 28 weeks’ gestational age
- Male is the predominant sex
- 8th leading cause of infant death
Diff dx of hyaline membrane disease
- Early-onset group B streptococcal pneumonia and/or sepsis
- Transient tachypnea of newborn
- Meconium aspiration pneumonia
Hyaline membrane disease diagnostic tests & interpretation
- CBC and blood cx- r/o sepsis and pneumonia
- Electrolytes: Monitor for hypoglycemia/hypocalcemia
- Arterial blood gases (ABGs)
- Hypoxemia (which responds to supplemental oxygen)
- Features of respiratory and metabolic acidosis
- Chest x-ray (CXR): diffuse reticulogranular pattern (ground-glass appearance)
- Air bronchograms
- Low lung volumes
Hyaline membrane disease ECHO
Consider if murmur is present
- -To evaluate for patent ductus arteriosus (PDA)
- -Contribution to lung disease due to L → R shunting
When would you use humidified oxygen-enriched gas in hyaline membrane disease?
if the baby is breathing on their own.
When would you use CPAP in hyaline membrane disease?
if infant is active and breathing spontaneously
When would you use positive-pressure ventilation per ETT in hyaline membrane disease?
If respiratory failure occurs (i.e., respiratory acidosis, apnea, or hypoxia despite nasal CPAP)
Management/monitoring of hyaline membrane disease
- Transcutaneous monitors to measure CO2 tension as necessary
- Constant pulse oximetry
- Umbilical artery catheter placement for continuous BP monitoring and sampling ABGs
Where does foreign body aspiration land?
Right mainstem bronchus
