Drug Induced Pulmonary Diseases Flashcards
What is the unique thing about lungs?
Exposed to the entire circulating blood volume along with outside environment via air
What controls breathing?
medulla oblongata stimulates respiratory muscles
How does breathing happen?
Medulla oblongata stimulates diaphragm which decreases intra horacic pressure resulting in external air entrance into pharynx, then trachea, bronchi, bronchioles and alveoli
What is the site of carbon dioxide and gas exchange?
alveoli exposed to blood capillaries
What are two acute life threatening respiratory complications?
hypoxic respiratory failure-can’t get oxygen to tissues
-respiratory acidosis-Co2 accumulation
What are 3 common drugs that induce pulmonary toxicity and how do they compare in mortality?
- methotraxate- small 1%
- bleomycin-moderate-25%
- carmustine induced pulmonary fibrosis=90%
What populations are predisposed to drug induced pulmonary problems?
- age
- also exposure to environmental toxins
- smoking
- genetic
- underlying lung disease
- inflammatory conditions like RA, IBD
How should you go about diagnosing drug induced pulmonary injury?
- clinical suspicion is high
- obtain medication history
- pulmonary function tests
- bronchoscopy and or biopsy
- typically a diagnosis by exclusion
- need familiarity with patient and good history
What are two ways drugs can induce apnea?
- CNS depression
- respiratory muscle dysfunction
What agents can causes CNS depression apnea?
narcotic analgestics
benzodiazepines
-high dose antihistamines
-alcohol
What can happen if you over oxygenation patients with apnea from CNS depression?
IT can be compounded by peristant hypercapnia because the brain isn’t signaling repiratory muscles to breath because it accustomed to high PO2 levels
What drugs can cause apnea from respiratory muscle dysnfunction?
- neuromuscular blockers
- aminoglycosides
- digitalis
What drugs can compound apnea from respiratory muscle dysfunction?
myopathy inducing agents
- corticosteroids
- high dose (over 2mg/kg/day)
What drugs commonly cause a cough?
ACE inhibitors
Describe an ACE induced cough
more common in women
- non-productive, dry, persistent
- possible elevated bradykinin
What do you do about drug induced cough?
no treatment
- need to substitute ACE for alternative medicine
What drugs can cause bronchospasms?
- aspirins
- beta blockers
- contrast
What increases risk for drug induced bronchspasms?
underlying asthma or COPD
What do you do about drug induced bronchospasms?
remove offending agent
-use bronchodilator
What is the “aspirin sensitivity triad”?
severe asthma, nasal polyps plus aspirin = aspirin induced asthma/bronchospasm
-accompanied by rhinohea, upper extremity flushing and conjunctivitis
How do you treat a asprin induced bronchospasm?
if they don’t need aspirin, don’t use it (along with other COX inhibitors)
-desensitize by starting at low doses and titrating up in controlled environment
What also has cross reactivity for aspirin induced asthmas?
other COX inhibitors
-yellow dye
Which beta blockers are more likely to induce an asthma attack?
non-selective (propranolol)
-choose a beta 1 specific antagonist
Which beta blockers are preferred in asthma patients?
bisoprolol, atenolol, metoprolol
-they are beta one specific
What are common offending agents in drug induced pulmonary edema?
- IV fluids and blood products
- narcotics
- beta-adrenergic agonists
- corticosteroids
- some chemo agents
What does drug induced pulmonary edema present as?
- bilateral, patchy x-ray
- actue dyspnea, alveolar opacities, hypoxia
How do you treat drug induced pulmonary edema?
remove offending agents
-volume management -can use diuretics
Pathological mechanism of drug induced pulmonary edema?
capillary leak
What is drug induced pulmonary fibrosis (IPF)?
replacement of normal lung tissue with fibrous or connective tissue
What are common offending agents in IPF?
- amiodarone
- methotrexate
- bleomycin
- carmustine
- busulifan
- cyclophosphamide
What are predisposing factors for IPF?
- cumulative dose
- increasing age
- radiotherapy
- oxygen therapy
- concomitant cytotoxic therapy
- pre-existing pulmonary disease
What doses of amiodarone put patients at risk for IPF?
over 400mg daily for more than 2 months
Clinical findings in amiodarone IPF?
exertional dyspnea
nonproductive cough
weight loss
occasional low-grad fever
Treatment for IPF from amiodarone?
no proven treatment optios
-DC med
What is BOOP?
bronchiolitis obliterans organizing pneumonia
-a non-infectious pneumonia that causes inflammation of bronchioles and alveolar exudate that can become fibrotic
Who is at risk for BOOP?
- underlying inflammatory disease
- lupus
- RA
- schleroderma
What do you do about BOOP?
- remove offending agents (amidoraone, amphotericin, bleomycin, cyclophosphamide)
- administer corticosteroids
When is BOOP typically diagnosed?
After it is misdiagnosed for pneumonia and the treatment doesn’t work or they patient gets better for a little while but it comes back
How long do you need to administer corticosteroids to treat BOOP?
usually a 6month-1 year taper
What is a diffuse aveolar hemorrhage (DAH)?
blood collection with alveoli
- from damage to small pulmonary vessles
- causes impaire oxygen exchange
DAH presentation
hemopytysis, dyspnea, cough, fever
How is DAH diagnosed?
brochoscopy-can see blood
Offending agents for DAH?
sirolimus, zathioprine, penicillamine
What do you do about DAH?
poor prognosis
-no real treatment
What medication induced non-lung tissue insults can compromise respiratory status?
- pulmonary embolism caused by BC or hormonal replacement therapy
- pulmonary hypertension from amphetamines and fenfluramine
- pulmonary vascular occlusive disease from bleomycin, busfulfan, carmustine
What causes drug induced eosinophilic pneumonia?
eosinophilic immune response
-lung inflitration
What are common offending agents of eosinophilic pneumonia?
nitrofurantion, para-aminosalcylic acid
- amiodarone
- iodine
- captpril
- gold salts
How is esoinophilic pneumonia diagnosed?
bronchoscopy show esosinphils
Can too much oxygen be toxic?
Yes, too much free radical production
What medications can increase oxidant production?
bleomycin, cyclophosphamide, nitrofurantoin, paraquat
Should oxygen be used for eosinophilic pneumonia from nitrofurantion?
NO, already produces oxidants
Should oxygen be used to treat pulmonary problems from bleomycin or cyclophosphamide?
NO, already produce oxidants
Which drug induced pulmonary disease affect the alvoeli?
pulmonary edema
BOOP
diffuse alveolar hemmorhage
Which drug induced pulmonary disease affect the pulmonary connective tissue?
pulmonary fibrosis
Which drug induced pulmonary disease affect the bronchus or large airways?
cough and bronchospasm
responsibilities of lungs
- phonation
- foreign matter defense mechanism
- metabolic functions
phonation
production of adequate air pass by vocal chords
foreign matter defense mechanism of lungs
mucociliary defense
alveolar macrophages
metabolic functions of lungs
- angiotensin I conversion
- bradykinin inactivation
- surfactant release
- inflammatory mediators
Acute life threatening complications of pulmonary compromise
- hypoxic respiratory failure
- respiratory acidosis
Prolonged complications of pulmonary compromise
- decreased functional status
- impaired QOL
T/f drug initiation should precede symptoms (drug induced pulmonary injury)
true
Amiodarone can cause
BOOP
eosinophilia pneumonia
pulmonary fibrosis
Bleomycin can cause
- BOOP
- pulmonary fibrosis
- oxygen toxicity
- pulmonary vascular occlusive disease
Methotrexate can cause
- pulmonary fibrosis
Carmustine can cause
- pulmonary fibrosis
- pulmonary vascular occlusive disease
Cyclophosphamide can cause
- BOOP
- Pulmonary fibrosis
- Oxygen toxicity
Nitrofurantoin can cause
- eosinophilia pneumonia
- oxygen toxicity
