|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
- 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 severity of illness
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.
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. PFT's: 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
Mild Intermittent: Less than 2 times per week or 3-night symptoms per month
- Step 1: Short-acting beta2 agonist (SABA) PRN
Mild Persistent: More than 2 times per week or 3-4 night symptoms per month
- Step 2: Low-Dose inhaled corticosteroids (ICS) daily
Moderate Persistent: Daily symptoms or more than 1 nightly episode per week
- Step 3: Low-Dose ICS + Long-acting beta2 agonist (LABA) daily
- Step 4: Medium-Dose ICS +LABA daily
Severe Persistent: Symptoms several times per day and nightly
- Step 5: High-Dose ICS +LABA daily
- Step 6: High-Dose ICS +LABA +oral steroids daily
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.
Patient will present as → a 3-year-old girl with growth retardation who has a long history of recurrent pneumonia and chronic diarrhea. Her mother states that he has 6-8 foul-smelling stools per day. Physical exam reveals a low-grade fever, scattered rhonchi over both lung fields, crepitant rales at the left lung base, and dullness to percussion. Other findings include mild hepatomegaly and slight pitting edema of the lower extremities. CXR reveals hyperinflation, mucus plugging, and focal atelectasis. Labs reveal an elevated quantitative sweat chloride test.
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
- Maintenance: Chest physiotherapy, high-fat diet, supplement fat-soluble vitamins (A, D, E, K)
- Acute exacerbations: Antibiotics
|Foreign body aspiration
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 and 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
|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
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
- 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 and production of copious foul-smelling sputum, frequent respiratory infections
DX: CXR = linear “tram track” lung markings, dilated and thickened airways – “plate-like” atelectasis; CT chest = gold standard
- Crackles, wheezes, purulent sputum
TX: ambulatory oxygen, aggressive antibiotics for acute exacerbations, CPT (chest physiotherapy = bang on the back); eventual lung transplant