CF + ARDS Flashcards
CF definition
Cystic fibrosis(CF), also calledmucoviscidosis
Autosomal recessive genetic disease
Mutations of the CF transmembrane conductance regulator (CFTR) gene
Abnormal transport of chloride and sodium across secretory epithelia
Resulting in thickened, viscous secretions
Affects the exocrine function of thelungs,liver,pancreas,small bowel,sweat glands,and the male genital system
What genetically causes CF?
Homozygous defect of theCFTRgene located on chromosome 7q31.2.
Gene encodes for a transmembrane protein known as cystic fibrosis transmembrane regulator (CFTR) which is responsible for regulating chloride passage across cell membranes.
There are at least 6 classes of mutations, the commonest being ∂F508 (66-70%
1) Who is Cf usually Dxd in?
2) What is the prognosis?
1) Typically diagnosed in pediatrics
~ 1:3000 live births
2) Median survival age now > 40 years, ~ 50% of CF population
What would cause a high index of suspicion for CF in adults?
Frequent/recurrent pulmonary infections
Chronic sinusitis
Severe nasal polyposis
Non-TB Mycoplasma infections
Allergic bronchopulmonary aspergillosis (ABPA)
Bronchiectasis (end stage)
+ sputum culture for Burkholderia cepacia – pathognomonic for CF
Male infertility
Hepatic, recurrent pancreatitis, diabetes
Describe CF in adults
1) Patients diagnosed in adulthood were more likely than children to present with gastrointestinal symptoms, diabetes mellitus, and infertility
2) Adults presenting with CF were more likely than children to have unusual genetic mutations, normal pancreatic function, and equivocal results on sweat chloride tests
Persistent productive cough frequently with hemoptysis
Mucus plugs
Hyperinflation (emphysema) of the lung fields on chest radiograph
Spirometry consistent with obstructive airway disease (low FEV1/FVC)
This describes what?
Respiratory manifestations of CF:
Chronic rhinosinus disease can occur with what?
CF
CF CXR
Although the entire lung is affected, there is a predilection for:
-Central (perihilar) distribution
-Upper lobes
-Apical segment of lower lobes
-Other features include: hyperinflation, regions of consolidation, lymph node enlargement, pneumothorax and pulmonary arterial hypertension.
Cystic fibrosis: Describe how it’s diagnosed (2 parts)
Newborn universal screening
Diagnosis:
1) -Clinical symptoms in 1 organ system or
-Positive newborn screening (positive sweat chloride test Cl >60 mEq/L) or
-Sibling with CF
AND
2) Evidence of CF: Transmembrane conductance Regulator (CFTR) gene dysfunction
-Sweat test has been mainstay (positive sweat chloride test Cl >60 mEq/L)
-Molecular testing demonstrating CFTR gene mutation
Nasal Potential Difference (NPD)
Describe a sweat chloride test for CF
Collection of sweat with pilocarpine ionophoresis to determine chloride concentration:
1) Normal = < 29 mmol/L – rules out in 99% of cases
Intermediate = 30-59 mmol/L – repeat or molecular
2) Abnormal = > 60 mmol/L = CF
Describe molecular testing for CF
CFTR gene screening in newborn
CFTR gene sequencing
Nasal Potential Difference
Used when above still indeterminant
1) ____% CF patients die from complications of lung infections
2) The cardinal feature of CF lung disease are?
1) 95%
2) Pulmonary exacerbations, bronchiectasis, and respiratory failure
1) What are 2 goals of adult CF Tx?
2) What are the cornerstones of management?
1) Maintain lung function
Control/minimize impact of CF affected organ disease
2) Airway clearance
Antibiotics
Nutritional support
Psychosocial support
Describe the role of a PCP in CF
1) Promoting general health – BMI, diet, exercise
2) Encourage healthy BMI…..lower BMI associated with worsening pulmonary status (FEV1) (Females > 22; Males > 23)
3) Nutritional supplements and pancreatic enzymes to maintain calorie intake
4) Screening for and managing DM
5) Encourage compliance with therapies
6) As adults with CF live longer – other general screening and vaccinations important
7) Mammogram, colon cancer screening, paps, etc.
List some causes of ARDS
1) Massive trauma
2) Severe resp. disorder
3) Prolonged mechanical ventilation
4) Hemorrhagic shock
5) Fat emboli
6) Septic condition
Acute respiratory distress syndrome (ARDS): What is it?
Non cardiogenic pulmonary edema
ARDS:
1) Most cases associated with what?
2) What does alveolar injury result in?
3) What is a key Sx?
1) Pneumonia +/- sepsis or non-pulmonary sepsis
2) Accumulation of inflammatory mediators & cells
3) Hypoxia
ARDS oldcarts
CC: acute &/or worsening dyspnea
Onset, duration, timing – acute new or worsening respiratory symptoms within 1 week of a known insult
Location: pulmonary
Characteristics – progressive dyspnea leading to respiratory failure
Aggravating – pulmonary or extrapulmonary insult
Alleviating – none (mechanical ventilation)
Radiation – hypoxia and respiratory failure
Associated symptoms – respiratory failure leading to hypoxia, MS changes, and cardiovascular collapse
Describe what you’ll see on an exam of a pt with ARDS
Progressive respiratory failure
Vital sign instability (tachypnea, pulse ox, tachycardia, hypotension …)
Progressive dyspnea ….leading to hypoxia despite oxygen supplementation
Accessory muscles
Altered MS
Sepsis
Pulmonary
Diffuse crackles
Frothy pink sputum
Describe ARDS DDxs:
1) Main differentials
2) Key points
1) Pneumonia
Heart failure
Diffuse alveolar hemorrhage
2) Timing of symptoms
Bilateral opacities on chest imaging not fully explained by effusions, lobar or lung collapse, or nodules
Covid-19 or other viruses: cough, myalgia, fatigue, SOB, diarrhea
ARDS Tx:
1) How do you manage underlying issues?
2) Describe Invasive respiratory support
3) What else?
1) Treat pneumonia or any other conditons
2) Intubation and ventilator support
PEEP to maintain PaO2 ~ 60 mmHg (SaO2 ~90%)
Fluid management
Describe uncomplicated pneumonia
1) S/S of pulmonary inflammation
2) Fever, chills, fatigue, sputum, pleuritic CP, infiltrates
3) Hypoxia should respond to oxygen administration
Treatment entails antibiotics
Describe complicated pneumonia
1) S/S of pulmonary inflammation
2) Hypoxia does not correct with oxygen administration and ARDS should be suspected and confirmed based on above criteria
3) Treatment entails antibiotics and ventilator management
