Transcript Cystic Fibrosis

Cystic Fibrosis
Module C
Chapter 41
Objectives
• State the clinical definition for Cystic Fibrosis.
Describe the anatomic alterations of the lungs
in Cystic Fibrosis.
• Describe the etiology of Cystic Fibrosis.
• List the clinical manifestations seen in Cystic
Fibrosis.
• Describe the management of Cystic Fibrosis.
• Indicate the lab test used to evaluate a patient
for cystic fibrosis and give normal values and
values used to identify cystic fibrosis.
Definition
• Formerly known as Mucoviscidosis.
• An inherited disease of the exocrine
glands, primarily affecting the GI and
respiratory systems, and usually
characterized by COPD, exocrine
pancreatic insufficiency, and
abnormally high sweat electrolytes.
Exocrine Glands
• Exocrine glands are glands whose
secretions pass into a system of ducts that
lead ultimately to the exterior of the body.
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Sweat Glands
Pancreatic ducts
Intestinal ducts
Liver & bile ducts
Reproductive glands
Lungs (bronchial glands)
Incidence
• Most common life-shortening disease
genetic disease in US
• Affects about 30,000 children and adults in US.
• 1 in 3,500 live births.
• Greater incidence in white births.
• 10,000,000 symptomless carriers (1 in 25).
• 80% diagnosed by age three; ~10% at age 18
or older.
Etiology
• Various mutations of a single gene
located on chromosome 7.
• Gene cells normally produce a protein
called Cystic Fibrosis Transmembrane
Regulator (CFTR).
• A mutation known as DF508 results in
deletion of the amino acid phenylalanine
at position 508 of the CFTR protein.
(70% of all cases)
• This results in a defect in chloride
transport by epithelial cells (also Na and
K).
Etiology
• Carriers of a single defective gene have no
clinical disease.
• If both parents are carriers, children who
inherit one abnormal gene from each
parent will be homozygous and develop
CF.
• Regardless of sex, the children of two
carrier parents will have:
• a 25% chance of having CF,
• a 50% chance of being carriers,
• a 25% of being normal (non-carrier).
Pathology
• Nearly all exocrine glands are affected in varying
degree of severity.
• Three types of defects:
• Glands become obstructed by viscid material
(pancreas, intestines, bile ducts, gallbladder).
• Increased secretion of abnormal mucus (bronchial
glands)
• Histologically normal cells, but increased secretion of
Sodium and Chloride (sweat glands).
• The lungs may appear normal at birth but
abnormal structural changes occur rapidly.
Pathophysiology - Pulmonary
• Bronchial glands hypertrophy and there is metaplasia of
goblet cells.
• Impairment of mucociliary clearance.
• Mucous plugging leads to hyperinflation and atelectasis.
• Retained secretions lead to frequent infections
(pneumonia).
• Staphylococcus aureus
• Haemophilus Influenza
• Pseudomonas Aeruginosa (mucoid variant)
• Smooth muscle constriction.
• Chronic bronchitis, bronchiectasis and lung abscess.
• AIRWAYS – NOT GAS EXCHANGE UNITS.
Pathophysiology - Intestinal Tract
• Meconium Ileus: Obstruction of
the small intestine of the
newborn caused by impaction of
thick, dry tenacious meconium,
usually at or near the ileocecal
valve.
• Deficiency of pancreatic enzymes
• Earliest manifestation of CF
• Newborns have abdominal
distention and fail to pass stool
within 12 hours after birth
• Intestinal Obstruction occurs in
older children and adults
Pathophysiology - Pancreas
• Pancreatic ducts become plugged with mucous
which leads to fibrotic changes.
• Cannot digest fats, proteins and cannot break
down nutrients.
• Deficiency of vitamins A, D, E, K.
• Vitamin K deficiency leads to easy bruising and bleeding.
• Patients have difficulty gaining weight.
• Cachectic
• Vitamin D deficiency leads to  absorption of Calcium
and Phosphorus.
• Diabetes
Pathophysiology – Sweat Glands
• Glands secrete up to 4 times the normal
amount of Na and Cl.
• The actual volume of sweat does not change.
• Sweat Chloride concentration can be used
as a diagnostic indicator.
• “Kiss a baby”
• Greater than 60 mEq/L is diagnostic in
children.
• In adults, a concentration of greater than 80
mEq/L is usually required for a diagnosis.
Pathophysiology – Other
• Nasal Polyps and Sinusitis
• 20% of patients.
• Polyps are multiple and may cause nasal
obstruction and distortion of normal facial
features.
• Sterility
• 99% of men and many women are sterile.
• Women not likely to carry fetus to term.
• Infant will have cystic fibrosis or will be a
carrier.
Signs & Symptoms
• Vital Signs:
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Tachypnea
Tachycardia
Hypertension
May have increased temperature if infection present.
• Inspection:
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Use of accessory muscles during I & E.
Increased A-P diameter of the chest.
Pursed lip breathing.
Clubbing
Cyanosis
Signs & Symptoms
• Palpation:
• Decreased tactile and vocal fremitus.
• Percussion
• Hyperresonant percussion note.
• Auscultation
• Diminished breath sounds.
• Crackles, rhonchi, wheezing.
Cor Pulmonale
• Chronic hypoxemia
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Polycythemia
Pulmonary hypertension.
Distended neck veins.
Enlarged and tender liver.
Peripheral edema.
Pitting edema.
Spontaneous Pneumothorax
• 20% greater incidence.
• 50% recurrence rate.
• Symptoms include:
• Pleuritic pain
• Shoulder pain
• Sudden dyspnea
• Can be precipitated by
• Excessive exertion
• High altitude
• Positive pressure breathing
Pulmonary Function
• Obstructive Picture:
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Decreased FVC
Decreased flowrates
Increased RV, TLC, FRC
Flow Volume Loop
• Scooped out
Arterial Blood Gases
• Mild to Moderate CF
• Acute alveolar hyperventilation with
hypoxemia.
• Severe CF
• Chronic ventilatory failure with hypoxemia.
• Increased shunting.
• Watch out for “acute on chronic” condition
during exacerbations of disease.
Chest X-ray
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Translucent (dark)
Depressed or flattened diaphragms
Right ventricular enlargement
Areas of atelectasis and fibrosis
Pneumothorax
Abscess formation
Treatment
• Oxygen Therapy
• Treat hypoxemia ( / , shunt)
• Nutritional Support
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Pancreatic Enzymes to aid food digestion
Increase of calories by 50 – 100%
Multivitamins and minerals
Salt
• Mobilization of Bronchial Secretions
• Bronchial Hygiene Protocol
• Hyperinflation Protocol
• Aerosolized Medication Protocol
Bronchial Hygiene
• Hydration
• Cough Techniques
• Active Cycle Breathing, Autogenic Drainage,
• Deep Breathing
• IS, Flutter, PEP therapy
• Chest Physical Therapy
• Percussion & Vibration
• Postural Drainage
• Mucolytic Therapy
Active Cycle Breathing
Autogenic Drainage
PEP Therapy
• Used in the management of airway secretions
and atelectasis.
• Patient is instructed to inhale a volume of air
larger than Vt through a one way valve.
• Exhale actively through a fixed orifice to a
normal level.
• Fixed orifice is chosen to achieve a PEP of 10
to 20 cm H2O during exhalation.
• Perform 10-20 breaths followed by coughs.
PEP Therapy
Postural Drainage & Percussion
High Frequency Chest Wall
Compression
• ThAIRapy Vest
• Inflatable, personally
fitted jacket attached to
a large pump that
generates variable high
frequency oscillations
and applies that directly
to the chest wall.
• Pulse frequency is set
for 5-25 Hertz (300 to
1500 cycles/min).
Aerosolized Medications
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Mucolytics - Pulmozyme
Sympathomimetics
Parasympatholytics
Xanthines
Antibiotics - tobramycin, colisitin
Mechanical Ventilation
• Treat increased PaCO2 (and low pH)
• Use caution with increasing tidal volume.
• Increased RV leads to overdistension.
• Extend expiratory time.
• Auto PEEP
• Shorten inspiratory time (increase inspiratory flow rate).
• Use respiratory rate to control PaCO2.
• Control patient (?) pharmacologically.
• Permissive hypercapnia and acidosis.
• Treat reduced PaO2
• Usually a result of hypoventilation and /
• Responds well to increase in FIO2.
imbalance.
Home Care
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Patient, family education
Home oxygen
Aerosol therapy
CPT/PD
Future Therapies
• denufosol tetrasodium
• denufosol is designed to enhance the lung's
innate mucosal hydration and mucociliary
clearance through stimulation of the P2Y2
receptor.
• HUH?
Prognosis
• Diagnostic testing for the abnormal gene is
now available.
• Life expectancy is 37 years of age (CF
Foundation) with some patients living past
40 years. Death is usually due to
pulmonary complications
• Respiratory failure
• Heart failure