DISORDERS OF THE RESPIRATORY SYSTEM PART 2.1 (based on T) Flashcards
What is the 2nd most common cause of stridor in infancy?
Congenital subglottic stenosis.
What are the two types of congenital subglottic stenosis?
Membranous (involves true vocal cords) and cartilaginous (affects cricoid cartilage).
What are the classic symptoms of congenital subglottic stenosis?
Barking cough and biphasic or primarily inspiratory stridor starting early in life.
What condition should be suspected in infants under 6 months with recurrent or persistent croup?
Congenital subglottic stenosis.
What are two clinical clues suggesting congenital subglottic stenosis in an intubated infant?
Failure and difficulty of extubation.
How is congenital subglottic stenosis diagnosed?
Endoscopic evaluation.
What is the management for mild congenital subglottic stenosis?
Observation.
What are the management options for severe congenital subglottic stenosis?
Anterior cricoid split, laryngeal stent placement, or tracheotomy.
What is congenital vocal cord paralysis commonly associated with?
Developmental CNS anomalies, cardiovascular, and respiratory system anomalies.
What is a possible perinatal cause of congenital vocal cord paralysis?
Stretching of the laryngeal nerve during delivery.
What three aspects are affected in congenital vocal cord paralysis?
Phonation, respiration, and deglutition.
What diagnostic test is recommended for congenital vocal cord paralysis?
Direct laryngoscopy of the dynamic larynx.
What is the prognosis for mild congenital vocal cord paralysis?
Recovery within 6-12 months; observation is recommended.
What is the treatment for bilateral congenital vocal cord paralysis?
Tracheotomy.
What is the treatment for unilateral congenital vocal cord paralysis?
Laryngoplasty.
What additional therapy is recommended for congenital vocal cord paralysis?
Speech therapy with proper treatment.
What is tracheomalacia?
A condition characterized by the collapsibility of the trachea due to weak tracheal cartilage.
What part of the trachea is most affected by tracheomalacia?
Distal third of the trachea.
What are the causes of tracheomalacia?
Congenital, intrinsic, extrinsic, or acquired.
What are the symptoms of tracheomalacia?
Expiratory stridor or wheeze, harsh barky cough, episodic reflex apnea, cyanosis, and dying spells.
What worsens tracheomalacia symptoms?
Salbutamol nebulization.
What are the diagnostic tests for tracheomalacia?
Lateral chest radiography, cinefluoroscopy, and endoscopic evaluation.
What is the triad seen in tracheomalacia on imaging?
Narrowing of the anteroposterior tracheal diameter, ballooning of the posterior membranous wall, and loss of the C-shape ring.
What is the usual prognosis for congenital tracheomalacia?
Resolves spontaneously by 18-24 months.
What is the management for tracheomalacia in respiratory distress?
Continuous positive airway pressure (CPAP).
What causes tracheoesophageal fistula (TEF) and esophageal atresia (EA)?
Incomplete separation of the primitive foregut into respiratory and digestive tracts at 4 weeks of gestation.
How many types of EA and TEF exist?
Five.
What are the symptoms of TEF and EA?
Choking, coughing, respiratory difficulty, cyanosis, gastric distention, continuous vomiting, and failure to thrive.
What are the key radiographic findings in TEF and EA?
Coiling of the nasal catheter at the esophageal pouch, migratory pulmonary infiltrates, and distended stomach.
What is the definitive diagnostic test for TEF and EA?
Endoscopy.
What is the primary treatment for TEF and EA?
Corrective surgery.
What are some post-repair complications of TEF and EA?
Tracheomalacia, GER, esophageal stricture, and recurrent chemical pneumonitis.
What causes vascular ring anomalies?
Abnormalities in the aortic arch complex.
What are the symptoms of vascular ring anomalies?
Biphasic stridor, expiratory wheezing, croupy barking cough, reflex apnea, cyanosis, recurrent respiratory infections, and dysphagia with solid foods.
What is the most severe type of vascular ring anomaly that presents in infancy?
Double aortic arch.
What is a pulmonary artery sling?
A condition where the left pulmonary artery arises from the right, encircles the trachea, and compresses the trachea and right main bronchus.
What structure is compressed in a pulmonary artery sling?
The lower trachea and right main bronchus.
What symptoms can tracheal compression in pulmonary artery sling cause?
Airway obstruction, stridor, wheezing, or respiratory distress.
What symptoms can esophageal compression in pulmonary artery sling cause?
Feeding difficulties, dysphagia, or reflux.
What diagnostic tests are used for vascular ring anomalies?
Barium esophagogram, bronchoscopy, and chest CT scan with contrast.
What is the definitive treatment for vascular ring anomalies?
Surgical correction.
How do symptoms change after surgical treatment of vascular ring anomalies?
Immediate improvement, with complete resolution over time.
A 5-month-old female presents with cough, fever, dyspnea, and absent breath sounds in the right hemithorax. CXR shows homogeneous opacity of the right lung, cardiac displacement to the right, and left lung hyperinflation. What is the most likely diagnosis?
Pulmonary agenesis, pulmonary aplasia, or pulmonary hypoplasia.
What are the key differences between pulmonary agenesis, pulmonary aplasia, and pulmonary hypoplasia?
Pulmonary agenesis: Complete absence of lung tissue and structures.
Pulmonary aplasia: Underdeveloped lung tissue present but poorly formed.
Pulmonary hypoplasia: Incomplete lung development due to external factors.
What fetal factors can lead to pulmonary hypoplasia?
Inadequate thoracic space (e.g., congenital diaphragmatic hernia), decreased fetal breathing, insufficient amniotic fluid (oligohydramnios), renal bladder outlet obstruction, abnormal blood supply.
What are the stages of lung development?
- Embryonic (Weeks 4-7) - Lung buds form.
- Pseudoglandular (Weeks 5-17) - Bronchial tree develops.
- Canalicular (Weeks 16-25) - Alveolar ducts form.
- Saccular (Weeks 24-Birth) - Alveolar sacs form, surfactant produced.
- Alveolar (Weeks 36-8 years) - Alveoli mature.
What are the clinical presentations of pulmonary agenesis or aplasia?
Small thorax, heart deviation towards affected side, dull percussion, diminished breath sounds, scoliosis.
What imaging is used to diagnose pulmonary agenesis or hypoplasia?
Prenatal ultrasound/MRI, postnatal CT or contrast-enhanced MR angiography.
What are complications of pulmonary agenesis?
Pneumothorax, scoliosis, repeated lower respiratory tract infections, chronic pulmonary insufficiency.
What is congenital lobar emphysema (CLE)?
Overexpansion of a pulmonary lobe due to intraluminal obstruction or extraluminal compression, leading to alveolar overdistention.
What are the symptoms of congenital lobar emphysema?
Easy fatigability, progressive respiratory distress, persistent wheezing, increasing cyanosis within the first 4 weeks of life.
What are the key physical exam findings of congenital lobar emphysema?
Affected side appears hyperexpanded, hyperresonance on percussion, decreased or absent breath sounds, contralateral mediastinal shift.
What is the treatment for congenital lobar emphysema?
Mild cases: Close monitoring. Severe life-threatening cases: Lobectomy.
What is pulmonary sequestration?
A non-functioning pulmonary tissue with no connection to the tracheobronchial tree, receiving blood supply from an aberrant systemic artery.
What is the difference between intralobar and extralobar sequestration?
Intralobar: Embedded in normal lung, no separate pleura, often in posterior basal segment of the left lower lobe, presents with recurrent pneumonia, cough, or hemoptysis. Extralobar: Has its own pleura, found outside the lung, usually asymptomatic.
What is congenital cystic adenomatoid malformation (CCAM)?
A developmental abnormality of the lung characterized by the adenomatous overgrowth of terminal bronchioles leading to cystic lung lesions.
What is the most common presentation of CCAM?
Respiratory distress at birth, diagnosed prenatally via ultrasound or postnatally via chest X-ray or CT scan.
What are the types of CCAM based on the Stocker classification?
Type 0: Rare, involves entire lung, usually fatal.
Type 1: Most common (60-70%), single or multiloculated cysts (2-10 cm).
Type 2: Multiple small cysts (0.5-3 cm), associated with other anomalies.
Type 3: Solid-appearing, alveolar origin.
Type 4: Large cysts up to 10 cm, associated with pneumothorax.
What is congenital diaphragmatic hernia (CDH)?
A defect in the diaphragm allowing abdominal organs to herniate into the thoracic cavity, impairing lung development.
What are the types of congenital diaphragmatic hernia?
Bochdalek hernia (posterolateral defect, most common, usually on the left), Morgagni hernia (anterior defect, right-sided, often asymptomatic).
What is eventration of the diaphragm?
A condition where the diaphragm is thinned out and allows abdominal contents to push into the thoracic cavity.
What are the key exam findings in congenital diaphragmatic hernia?
Respiratory distress, cyanosis, barrel-shaped chest, scaphoid abdomen, decreased breath sounds, possible bowel sounds in the thorax.
What is the management of congenital diaphragmatic hernia?
Immediate intubation, nasogastric decompression, surgical repair, extracorporeal membrane oxygenation (ECMO) if needed.
A 30-month-old girl presents with difficulty breathing, cough, and fever for two days. PE: dyspnea, subcostal and intercostal retractions, rales in both lung fields, O2 sat 84% on room air. What is the next step in management?
Administer oxygen, assess for pneumonia, and consider imaging to rule out congenital lung anomalies.
What is the definition of pneumonia?
Inflammation of lung tissue caused by an infectious agent, leading to acute respiratory signs and symptoms.
What are the two classifications of pneumonia based on where it was acquired?
Community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP).
What is the most consistent sign of pneumonia?
Tachypnea.
What are the physical examination findings in pneumonia?
Chest indrawing, fever, tachycardia, crackles, inequality of breath sounds, dullness on percussion, nasal flaring, labored breathing, apnea.
What are the diagnostic tests for pneumonia?
Chest X-ray, ABG (arterial blood gas), CBC (complete blood count), BCS (blood culture and sensitivity), pleural fluid and tracheal aspirate.
What are the common pathogens causing pneumonia in newborns?
Group B Streptococci, Gram-negative bacilli, Chlamydia.
What are the common pathogens causing pneumonia in children?
Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis.
What are the common pathogens causing pneumonia in adolescents?
Streptococcus pneumoniae, Mycoplasma pneumoniae, Moraxella catarrhalis.
What often predisposes the lung to bacterial pneumonia?
A preceding viral infection.
What is the chest X-ray finding in bacterial pneumonia caused by Streptococcus pneumoniae?
Lobar consolidation (solid).
What pathogens cause pneumatocele formation on CXR?
Staphylococcus aureus and Klebsiella pneumoniae.
What laboratory findings are seen in bacterial pneumonia?
Leukocytosis, elevated ESR and CRP.
What is the most common cause of respiratory infections?
Viruses.
What is the pathophysiology of viral pneumonia?
Destruction of ciliary epithelium, sloughing of cellular debris, infiltration of mononuclear cells, inflammatory edema, mucus secretion.
What is the treatment for viral pneumonia?
Supportive care; antibiotics are not necessary.
What is the common etiologic agent of respiratory infections in infants?
Respiratory syncytial virus (RSV).
What are the clinical findings in RSV infection?
Fever, coughing, rales, wheezes.
What is the treatment for RSV infection?
Supportive care; Ribavirin nebulization for high-risk patients.
What respiratory infection is commonly caused by parainfluenza virus?
Croup.
What is the treatment for croup?
Supportive care, glucocorticoids, epinephrine nebulization.
What are the best clinical predictors of radiographically confirmed pneumonia in children?
Tachypnea, retractions, nasal flaring, oxygen saturation <95%, grunting.
What is the best predictor of pneumonia in children?
Tachypnea.
What are the tachypnea cut-offs for different age groups?
Newborn: >60 bpm; 3-12 mos: >50 bpm; 1-5 yrs: >40 bpm; 5-12 yrs: >30 bpm; >12 yrs: >20 bpm.
What are the parameters used to determine the need for pneumonia admission?
Respiratory signs (cyanosis, head bobbing, retractions, apnea, grunting), CNS signs (altered sensorium, convulsion), circulatory signs (poor perfusion, pallor), general conditions (malnutrition, refusal to feed, dehydration, age <6 months).
What diagnostic aids confirm non-severe community-acquired pneumonia in an ambulatory setting?
Routine diagnostic aids are not necessary; medical history and physical examination are sufficient.
What diagnostic aids confirm severe community-acquired pneumonia in a hospital setting?
Chest X-ray (strongly recommended), POCUS (if performed by an expert), procalcitonin (PCT) in conjunction with clinical presentation and imaging, CBC, ABG, serum electrolytes.
Are sputum gram stain and culture routinely recommended for severe pneumonia?
No, they are not routinely recommended.
What happens to pH, PaCO2, and HCO3 in metabolic acidosis?
↓ pH, ↓ PaCO2, ↓ HCO3
What happens to pH, PaCO2, and HCO3 in metabolic alkalosis?
↑ pH, ↑ PaCO2, ↑ HCO3
What happens to pH, PaCO2, and HCO3 in acute respiratory acidosis?
↓ pH, ↑ PaCO2, ↑ HCO3
What happens to pH, PaCO2, and HCO3 in acute respiratory alkalosis?
↑ pH, ↓ PaCO2, ↓ HCO3
What clinical and ancillary parameters determine the need for antibiotic treatment in infants and children (3 months - 18 years) with community-acquired pneumonia?
Elevated WBC, Elevated CRP, Elevated PCT, Alveolar infiltrates in chest radiograph, Unilateral lung consolidation, Air bronchograms, Pleural effusion on ultrasound
What empiric treatment is effective for bacterial community-acquired pneumonia in non-severe cases?
Amoxicillin 40-50 mg/kg/day Q8 for 7 days OR 80-90 mg/kg/day Q12 for 5-7 days;
Amoxicillin-clavulanate 80-90 mg/kg/day Q12 (14:1 formulation) for 5-7 days;
Cefuroxime 20-30 mg/kg Q12 for 7 days
What empiric treatment is effective for bacterial community-acquired pneumonia in severe cases?
Penicillin G 200,000 units/kg/day Q6 (if Hib vaccinated);
Ampicillin 200 mg/kg/day Q6 (if incomplete/unknown Hib vaccination);
Cefuroxime 100-150 mg/kg/day Q8;
Ceftriaxone 75-100 mg/kg/day Q12-24;
Ampicillin-sulbactam 200 mg/kg/day Q6
What antibiotic is recommended when Staphylococcal pneumonia is suspected?
Clindamycin 20-40 mg/kg/day Q6-Q8;
Vancomycin 40-60 mg/kg/day Q6-Q8 for severe cases
What are alternative treatments for penicillin allergy in non-type 1 hypersensitivity?
Cefuroxime PO 20-30 mg/kg/day Q12 or IV 100-150 mg/kg/day Q8;
Ceftriaxone 75-100 mg/kg/day Q12-24
What are alternative treatments for penicillin allergy in type 1 hypersensitivity?
Azithromycin 10 mg/kg/day PO or IV Q24 for 3-5 days;
Clarithromycin 15 mg/kg/day Q12 for 7 days;
Clindamycin 10-40 mg/kg/day PO or 20-240 mg/kg/day IV Q6-Q8 for 7 days
When is a macrolide recommended for bacterial pneumonia?
When an atypical pathogen is suspected (Azithromycin 10 mg/kg/day PO or IV Q24 for 5 days; Clarithromycin 15 mg/kg/day Q12 for 7-14 days)
What is the recommended treatment for viral pneumonia in children?
Oseltamivir within 36 hours of laboratory-confirmed influenza infection
What clinical parameters indicate a good response to therapy in non-severe pneumonia?
Sustained clinical stability for past 24 hours: improved cough, normalization of body temperature without antipyretics within 24-72 hours
What clinical parameters indicate a good response to therapy in severe pneumonia?
Absence/resolution of hypoxia, danger signs, tachypnea, fever, tachycardia, and resolving/improving radiologic pneumonia
What should be done if a patient with non-severe pneumonia does not improve within 24-72 hours?
Consider alternative diagnosis, antibiotic resistance, coexisting infection, or complications (pleural effusion, necrotizing pneumonia, lung abscess)
What should be done if a patient with severe pneumonia does not improve within 24-72 hours?
Perform diagnostic evaluation (cultures, PCR, serology, imaging, biomarkers), consider referral for specialist assessment or possible intubation
What adjunctive treatments are effective for community-acquired pneumonia?
Vitamin A, Zinc, Vitamin D, Bronchodilators, Mucokinetics, Oral folate, Probiotics, Vitamin C, VCO, Nebulization with saline, Steam inhalation
What clinical parameters determine when switch therapy can be considered in severe pneumonia?
Parenteral antibiotic given for at least 24 hours, afebrile for at least 8 hours, able to feed, clinical improvement (no hypoxia, danger signs, tachypnea, fever, tachycardia)
What diagnostic tests are used for pneumonia assessment?
Pulse oximetry, Arterial blood gas, Spirometry, Peak expiratory flow rate, Thoracentesis
A newborn presents with respiratory distress and cyclic cyanosis relieved by crying. Failure to pass a nasal catheter suggests what congenital anomaly?
Choanal atresia
What is the cause of choanal atresia?
Persistence of a bony or membranous septum blocking the posterior nares
What are the types of choanal atresia?
Bilateral and unilateral
What are the clinical features of bilateral choanal atresia?
Immediate respiratory distress, asphyxia, and cyclic cyanosis in newborns
What are the clinical features of unilateral choanal atresia?
Not recognized until years later, presents with continuous nasal secretions and sinusitis
What is the hallmark clinical finding in choanal atresia?
Cyanosis that improves with crying
What is the most common congenital laryngeal anomaly?
Laryngomalacia
What is the cause of laryngomalacia?
Immaturity of laryngeal cartilage leading to supraglottic airway collapse
What is the hallmark sign of laryngomalacia?
Inspiratory stridor
When does stridor in laryngomalacia become noticeable?
Between the 2nd to 4th week of life
When does laryngomalacia usually resolve?
By 18 to 24 months of age
In what positions is laryngomalacia stridor heard loudest?
Supine position, while feeding, and during active/agitated states
What symptoms indicate severe laryngomalacia?
Dyspnea, cyanosis, and failure to thrive
What is the gold standard diagnostic test for laryngomalacia?
Laryngoscopy
What are the two types of laryngomalacia?
Bending type (omega-shaped epiglottis falling backward) and squeezing type (arytenoids pressing toward the center, obstructing airflow)
What is the initial management of mild laryngomalacia?
Observation, reassurance, and preventive measures
What are the treatment options for severe laryngomalacia?
Endotracheal intubation, tracheotomy, or epiglottoplasty (definitive procedure)
What is the most serious complication of laryngomalacia?
Acute respiratory compromise and failure
