Acute respiratory distress syndrome (ARDS) |
Patient will present as → a patient brought to the emergency room with acute onset of dyspnea and tachypnea. He has a long history of alcoholism and was involved in a motor vehicle accident two days ago. He is hypoxic with crackles auscultated bilaterally and frothy pink sputum. Chest radiography reveals diffuse bilateral infiltrates, which spare the costophrenic angle and air bronchograms. There is no cardiomegaly or pleural effusion noted. Oxygen saturation is 70%.
Acute respiratory distress syndrome (ARDS) is a type of respiratory failure characterized by fluid collecting in the lungs, depriving organs of oxygen
- ⇑ Permeability of alveolar-capillary membranes ⇒ development of protein-rich pulmonary edema (non-cardiogenic pulmonary edema)
- ARDS can occur in those who are critically ill or who have significant injuries ⇒ sepsis (most common), severe trauma, aspiration of gastric contents, near-drowning
People with ARDS have severe shortness of breath and often are unable to breathe on their own without support from a ventilator
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- Rapid onset of profound dyspnea occurring 12-24 hours after the precipitating event
- Tachypnea, pink frothy sputum, crackles
Chest radiograph shows air bronchograms and bilaterally fluffy infiltrate
- Normal BNP, pulmonary wedge pressure, left ventricle function, and echocardiogram
Treatment involves identifying and managing underlying conditions
- Tracheal intubation with the lowest level PEEP to maintain PaO2 >60mmHg or SaO2 >90
- ARDS is often fatal. The risk increases with age and the severity of illness
X-ray of a patient with ARDS. Note the diffuse bilateral infiltrates, which spare the costophrenic angle and air bronchograms |
Asthma (ReelDx) |
Patient will present as → a 5-year-old boy who is brought to the emergency department by his parents for a cough and shortness of breath. He has a past medical history of eczema and seasonal rhinitis. On physical exam, you note a young boy in respiratory distress taking deep, slow breaths to try and catch his breath. He has diminished breath sounds in all lung fields with prolonged expiratory wheezes.
asthma
You are called to see a 10 y/o with a cough and difficulty breathing
- Gender: Male
- Age: 10 years
- Weight: 50.7 lb/23 kg
- Temperature: 98.7 F/37.1 C
- Blood Pressure: 117/74
- Heart Rate: 114
- Respiratory Rate: 40
- Pulse Oximetry: 94% RA
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Presentation: Most often, young patients present with wheezing and dyspnea often associated with illness, exercise, and allergic triggers
Diagnosis and monitor with peak flow. PFTs: Greater than 12% increase in FEV1 after bronchodilator therapy
- FEV1 to FVC ratio < 80% (You would expect the amount of air exhaled during the first second (FEV1) to be the greatest amount
- In asthma, since there is an obstruction (inflammation), you will have a decreased FEV1 and, therefore, a reduced FEV1 to FVC ratio
Treatment guidelines:
The 2023 GINA strategy divides asthma treatment into two tracks for adults and adolescents:
- Track 1: The preferred treatment option is an as-needed combination low-dose ICS-formoterol.
- Track 2: An alternative option that uses SABA as the reliever along with a separate preventer inhaler. This track may be used if ICS–formoterol is not available or if patients have no risk factors for exacerbations.
Table 1: GINA Track 1
- Preferred initial treatment for most patients
- Suitable for patients who respond well to ICS and have a low risk of side effects
Table 2: GINA 2023 Track 2
- Alternative for patients concerned about ICS side effects or if ICS + LABA isn't preferred
- Can also be used for quick relief of symptoms, streamlining treatment
Acute treatment:
Oxygen, nebulized SABA, ipratropium bromide, and oral corticosteroids
Making Sense of Forced Vital Capacity
- Forced expiratory volume (FEV) measures how much air a person can exhale during a forced breath. The amount of air exhaled may be measured during the first (FEV1), second (FEV2), and/or third seconds (FEV3) of the forced breath. Forced vital capacity (FVC) is the total amount of air exhaled during the FEV test
- You would expect the amount of air exhaled during the first second to be the greatest amount. In asthma, since there is an obstruction (inflammation), you will have a decreased FEV1 and, therefore, a reduced FEV1 to FVC ratio.
Chest radiograph of a young woman who presented to the intensive care unit (ICU) with severe asthma showing hyperinflation |
Cystic fibrosis |
Patient will present as → a 7-year-old boy brought by his parents due to a persistent cough, wheezing, and recurrent lung infections since infancy. The parents also report the child having bulky, foul-smelling stools and difficulty gaining weight despite a good appetite. On examination, he appears underweight, with digital clubbing and crackles heard on lung auscultation. His growth chart shows him below the 3rd percentile for his age. A sweat chloride test shows a chloride level of 88 mmol/L (normal <40 mmol/L). His stool elastase test is low, indicating pancreatic insufficiency. Genetic testing confirms the diagnosis of cystic fibrosis with the identification of mutations in the CFTR gene.
Cystic fibrosis affects the cells that produce mucus, sweat, and digestive juices. It causes these fluids to become thick and sticky. They then plug up tubes, ducts, and passageways.
Etiology: Autosomal recessive mutation in the CFTR gene
- Abnormally thick mucus, difficulty clearing mucus
Presentation: Recurrent respiratory infections (especially Pseudomonas), steatorrhea
Diagnosis: Quantitative sweat chloride test
CXR may reveal hyperinflation, mucus plugging, and focal atelectasis
Treatment:
- Maintenance: Chest physiotherapy, high-fat diet, supplement fat-soluble vitamins (A, D, E, K)
- Acute exacerbations: Antibiotics
A 12-year-old girl with cystic fibrosis. a The AP radiograph shows mild to moderate general changes of cystic fibrosis, with increased linear markings and discrete nodular opacities (arrowheads) in the periphery of both lungs. Bronchiectases are suspected in the upper parts of both hilar regions (white arrows). b A tomosynthesis section |
Foreign body aspiration |
Foreign body aspiration
You are called to see a 7-month-old male with dry heaves, crying, and agitation shortly after a meal.
Patient
- Gender: Male
- Age: 7 months
- Height: Not Available
- Weight: Not Available
Vitals
- Temperature: 98.2 F/36.8 C
- Blood Pressure: Not Available
- Heart Rate: 137
- Respiratory Rate: 40
- Pulse Oximetry: 99% RA
Signs and Symptoms
- Dry heaves; crying; agitated.
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Patient will present as → a 2-year-old male child who is brought to the emergency department by his mother with a sudden onset of choking, gagging, coughing, and wheezing. Vital signs are temperature 37 ° C, pulse 120/min, and respirations 28/min. The physical examination reveals decreased breath sounds over the right lower lobe with inspiratory rhonchi and localized expiratory wheezing. The chest X-ray reveals normal inspiratory views, but expiratory views show localized hyperinflation with a mediastinal shift to the left.
Foreign body aspiration occurs when a foreign body enters the airways and causes choking. Objects can enter the esophagus through the mouth or enter the trachea through the mouth or nose
- Most often food can be life-threatening. 80% in mainstem or lobar bronchus right > left
- Risk factors include institutionalization, advanced age, poor dentition, alcohol, sedative use
Presentation (depends on the location of obstruction)
- Inspiratory stridor (if high in the airway) or wheezing and decreased breath sounds (if low in the airway)
CXR (expiratory radiograph) may reveal regional hyperinflation of the affected side
- ABG - necessary for appropriately evaluating ventilation, may be useful for following the progression of respiratory failure when it is of concern
Treatment: Remove foreign body with a bronchoscope
- Rigid bronchoscopy is preferred in children, while flexible is diagnostic and therapeutic in adults
- Complications include pneumonia, acute respiratory distress syndrome, asphyxia
Aspiration of a dental crown. This projects onto the right lower lobe bronchus. |
Hyaline membrane disease |
Patient will present as → a premature infant who is born at 32 weeks and, after several hours, develops rapid shallow respirations at 60/ min, grunting retractions, and duskiness of the skin. The chest X-ray reveals diffuse bilateral atelectasis, ground glass appearance, and air bronchograms.
Hyaline membrane disease (HMD), also called neonatal respiratory distress syndrome (RDS), is a condition in newborn babies in which the lungs are deficient in surfactant, preventing their proper expansion and causing the formation of hyaline material in the lung spaces
Etiology: Insufficient surfactant
- Population: Preterm newborn
- Chest radiograph: Ground glass appearance, air bronchograms, bilateral atelectasis
Treatment: Ventilation and steroids
Acute respiratory distress syndrome (ARDS) vs. Hyaline membrane disease/newborn respiratory distress syndrome (RDS)
- Hyaline membrane disease/respiratory distress syndrome in preterm infants (RDS) is often due to young gestational age, immature type II alveolar cells, and lack of alveolar surfactant, resulting in inadequate alveolar surface tension during expansion, which results in atelectasis, reduced gas exchange, severe hypoxia, and acidosis.
- Hyaline membrane disease and RDS are two names for the same thing!
- Acute respiratory distress syndrome (ARDS) in newborns and children is distinct from RDS/Hyaline membrane disease and involves diagnostic criteria (Montreux standard). Unlike RDS, ARDS of newborns and children is not based on a lack of alveolar surfactant.
- These diagnostic criteria for ARDS of newborns and children include:
- Acute exacerbation (within 1 week) after clinical or possible injury
- Not caused by RDS, transient tachypnea of the newborn (TTN), congenital malformations, atelectasis, local effusions
- Congenital heart disease that can be explained by pulmonary edema
- Oxygenation index (OI) value ≥4
Chest radiograph one day after birth of a boy after 29 weeks and 3 days of gestational age who developed respiratory distress. |
Bronchiectasis |
Patient will present as → a 25-year-old cystic fibrosis patient complaining of chronic, frequent coughing productive of yellow and green sputum. She recently recovered from a Pseudomonas spp. Pneumonia requiring hospitalization. On physical examination, you notice foul breath, purulent sputum, and hemoptysis, along with a CXR demonstrating dilated and thickened airways with “plate-like” atelectasis (scarring).
A condition in which the lungs' airways become dilated and damaged, leading to inadequate clearance of mucus in airways
- Mucus builds up and breeds bacteria, causing frequent infections - crackles, wheezes, purulent sputum
- A common endpoint of disorders that cause chronic airway inflammation (CF, immune defects, recurrent pneumonia, aspiration, tumor)
- Symptoms include a daily cough that occurs over months or years, production of copious foul-smelling sputum, and frequent respiratory infections
DX: CXR = linear “tram track” lung markings, dilated and thickened airways – “plate-like” atelectasis
TX: ambulatory oxygen, aggressive antibiotics for acute exacerbations, CPT (chest physiotherapy = bang on the back); eventual lung transplant
Chest X-ray of hyperinflated lung with bronchiectasis at the right upper lobe of a 12-year-old boy.
A CT scan demonstrating very pronounced bronchiectasis in a 75-year-old man, especially on the right (left in the picture). There is a florid superinfection with a large accompanying effusion
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