Changes of the respiratory system, frequent diseases

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Manifestation of Novel Social Challenges of the
European Union
in the Teaching Material of
Medical Biotechnology Master’s Programmes
at the University of Pécs and at the University
of Debrecen
Identification number: TÁMOP-4.1.2-08/1/A-2009-0011
Manifestation of Novel Social Challenges of the
European Union
in the Teaching Material of
Medical Biotechnology Master’s Programmes
at the University of Pécs and at the University
of Debrecen
Identification number: TÁMOP-4.1.2-08/1/A-2009-0011
Márta Balaskó and Miklós Székely
Molecular and Clinical Basics of Gerontology – Lecture
10
CHANGES OF THE
RESPIRATORY SYSTEM,
FREQUENT DISEASES
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Age-related changes of the
respiratory system 1
• In the course of aging the elements of
the respiratory system (chest, lungs,
airways) develop important
morphological alterations.
• Pulmonary functions: ventilation, gas
exchange, defense mechanisms, all
change with age!
• How much of this is intrinsic
pathophysiological (exhaustion of
adaptation mechanisms) and how much is
a consequence of environmental factors
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Age-related changes of the
respiratory system 2
• Respiratory muscles start to weaken at around
the age of 55, causing a restrictive
respiratory disorder.
• Chest compliance decreases, rib cartilage is
turned into bone, enhanced dorsal
kyphoscoliosis, aggravating the restrictive
respiratory disorders further.
• Elastic recoil of the lungs decreases, lung
compliance increases (because of the damage
to the elastic fibers) leading to emphysema.
In certain individuals the weakness of the
elastic fibers and the diminished inward pull
on the chest lead the expansion of the chest
and to the development of barrel chest.
In certain individuals, destruction
of the pulmonary elastic fibers
leads to a distension of the chest:
barrel-chest
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Normal
Barrel-chest
Age-related abnormal
changes in the respiratory
system 3
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Osteoporosis and vertebral compression may lead
to excessive kyphoscoliosis – enhanced dorsal
kyphosis, restrictive chest disorder.
Special complications
• In severe osteoporosis cough may lead to rib
fracture.
• In severe emphysema of the elderly cough may
lead to acute pneumothorax via rupture of one
of the thin distended bullae.
• Cardiopulmonal cachexia may develop. In
severe pulmonary diseases food intake may
induce such a severe dyspnea, that patients
would rather not eat. Deficiency of energy
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Living with osteoporosis:
kyphoscoliosis
At age 55
At age 65
At age 75
Age-related abnormal changes in the
respiratory system 4
Ventilation and diffusion
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• Eventually aging-associated emphysema
develops, due to a decrease of the elastic
fiber network (that would normally protect the
airways from collapsing in expiration by
anchoring them to nearby morphological units),
the small airways collapse during expiration
due to the positive pressure in the lungs.
• In case of airway inflammation small airways
grow narrower (due to inflammatory edema,
infiltration, increased mucus production,
increased bronchoconstriction). Abnormalities
of the small airways lead to uneven alveolar
ventilation, V/Q mismatch
• Obstruction of the small airways increases the
Age-related abnormal changes in the
respiratory system 5
Speed of airflow
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Dynamic respiratory parameters that take
into consideration the speed of airflow,
e.g. forced vital capacity (FVC)
decrease with age. Forced expiratory
volume in 1 second (FEV1) decreases
regularly by about 20-30 ml a year.
Narrowing of the small and bigger
airways further enhance the decline in
FEV1. (Diameter of small airways with a
narrower initial lumen tend to decrease
further due to a positive pressure
during expiration.) Smoking-induced
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% of FEV1 value at age 25
years
Age-related decline in FEV1
100
Never smoked or not
susceptible to its
effects
75
Stopped at
45
50
Smoked regularly and
susceptible to its
effects
Disabil
ity
25
Stopped at
65
Death
0
25
50
75
Age
Age-related abnormal changes in
the respiratory system 6
Respiratory regulation
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• Responsiveness of the respiratory center
to hypercapnia and hypoxia-induced
(peripheral chemoreceptor) stimuli is
steadily decreasing
• There is a steady decrease of 0.3% pO2
per year, due to the impairment of the
respiratory regulation (further decrease
is due to an impaired performance of the
lungs)
• By 70 years of age there is a 40-50%
decrease in the sensitivity. (Old
people tolerate rather than defend
Age-related abnormal changes in
the respiratory system 7
Defence mechanisms
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• Clearance: the intensity of the
mucociliary transport shows a negative
correlation with age.
• Loss of the cough-reflex that also
serves the clearance and defense of the
airways.
• Humoral immunity:
IgG and IgA do not change with age, but
IgM decreases
• Cellular immunity:
decreases with age (type IV late
Age-related abnormal
changes in the respiratory
system 8
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• The prevalence of airway infections is enhanced
in the elderly. Pneumonia develops frequently.
• Diagnosis is difficult:
- Due to the weakened immune system many nonspecific infectious agents are seen, symptoms
are also non-characteristic. Instead of fever,
cough, breathing-associated pain observed in
the young , confusion or incontinence maybe
the only sign of pneumonia.
- In hypovolemic patients chest X-rax may be
false negative.
- Due to the weakened immune system endogenic
exacerbations or exogenous reinfections are
common.
Age-related abnormal
changes in the respiratory
system 9
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• Prevalence of chronic obstructive lung
diseases (COPD) increases in the elderly, its
progression is enhanced in this age-group.
(Etiological factors of COPD, smoking or
occupational smoke and dust exposure act for
a longer time and cause more severe
abnormalities.)
• Symptoms and clinical findings of patient
with (previous diagnosis of) bronchial
asthma and COPD differ less and less with
aging. (Airway obstruction of older asthmatic
patients is not as reversible as it used to
be.)
• In smokers the prevalence of COPD is 5-7-
Age-related abnormal changes in the
respiratory system 10
Lung cancer in the elderly
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• Mean age of patients with lung cancer is 70
years. Only 3 % of them are below the age of 45
years.
• Smoking plays a primary role in the etiology.
(In male smokers the risk of developing lung
cancer is 22-times, in female smokers 12-times
(due to lower exposure) higher than that of
non-smokers. Smoking is responsible for more
than 80% of lung cancer mortality.)
• Treatment is not efficient, 60% of patients die
within 1 year, 75% within 2 years of diagnosis.
• The best prevention is being a non-smoker and
avoidance of cigarette (cigar, etc.) smoke.
• In Hungary, lung cancer present a significant
Age-related abnormal changes in the
respiratory system 11
Pulmonary fibrosis
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Definition
Accumulation of connective tissue in the lungs
(fibrosis), because of tissue damage/inflammatory
processes.
• Due to the destruction of the pulmonary parenchyma,
respiratory /diffusion surface decreases.
• Capillary diameter is diminished, pulmonary pressure
rises.
• Thickening of the alveolocapillary membrane develops.
• As a result, diffusion disorder, in severe cases even
alveolar hypoventilation is seen.
Causes
• medications: e.g. amiodarone, bleomycin,
cyclophosphamide, nitrofurantoin, methotrexate
• irradiation
• autoimmune alveolitis (in the elderly autoimmune
disorders are common)
Age-related abnormal changes in
the respiratory system 12
Pulmonary fibrosis
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Symptoms, complications
• Elastic resistance increases, inspiration requires
an effort. Restrictive ventilatory disorder is
observed.
• Superficial, frequent breathing is
characteristically seen that leads to the increase
in dead space ventilation.
• Airflow is diminished, consequently the risk of
airway infections, pneumonia and even lung cancer
is enhanced.
• Respiratory failure frequently develops. Diffusion
disorder itself leads to partial, alveolar
hypoventilation results in global respiratory
failure.
Treatment
Age-related abnormal changes in the
respiratory system 13
Sleep apnea syndrome
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Definition
Recurrent apneic/hypopneic prediods (>10 sec each,
>10/hour, >30/night) during sleep at night.
Types
• Central (C): sensitivity of the respiratory centre is
diminished
• Peripheral obstructive (P): collapse of distended,
enlarged pharyngeal tissues (snoring), nasal conchae,
enlarged tongue may cause obstruction
Etiology
• aging risk above 65 years 2-3-times higher (C, P)
• stroke, brain tumors (C)
• alcohol, tranquillizers (C, P)
• atrial fibrillation, congestive heart failure (C), very
frequent in the elderly!
• obesity, fat accumulation in pharyngeal tissues (P)
• male gender 2-times increased risk (P)
• menopause (P)
Age-related abnormal changes in the
respiratory system 14
Sleep apnea syndrome
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Symptoms
loud snoring (peripheral obstructive form, in a dorsal
position), frequent waking day-time somnolence,
exhaustion, increased risk for accidents
Consequences
• many occasions of respiratory failure of short duration
at night
• treatment-refractory systemic hypertension, pulmonary
hypertension
• tendency to develop congestive heart failure, with
increased risk for pulmonary edema
• morning headache
• sleepiness, daytime somnolence, (car)accidents
• increased risk for dementia and cognitive disorders
• alterations of personality, irritability, aggression
Treatment
• reduction of body weight
• sleeping on one side (not on the back)
Age-related abnormal changes in
the respiratory system 15
Pulmonary embolism in the elderly
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Definition
Embolism obstructing smaller or larger pulmonary
arteries
Causes (in the elderly)
• deep venous thrombosis (e.g. from the lower limb or
pelvic region)
• immobilization
• trauma, fractures, surgical fracture treatments (in
the latter fat embolization may also develop)
• varicosity
• compensatory polyglobulia induced by hypoxic states
(COPD, pneumonia)
• hemoconcentration associated with frequent
hypovolemias
• obesity
• polycythaemia vera
Age-related abnormal changes in
the respiratory system 16
Pulmonary embolism in the elderly
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Symptoms (non-specific)
dyspnea, hemoptysis (blood in sputum), respirationassociated (sharp, pleural) chest pain confusion,
collapse, tachycardia
Diagnosis
In about 30% of the cases, it is not diagnosed.
This ration is higher in the elderly.
• Signs of enhanced coagulation and fibrinolysis
(fibrin degradation products, D-dimer)
• CT
• Lung scintigraphy
• pulmonary angiography
• Doppler ultrasound (venous)
• Phlebography
Treatment
Age-related abnormal changes in the
respiratory system 17
Respiratory failure
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• Prevalence is more than 10 % in adults
• Incidence of acute respiratory failure
increases from
60-80/100,000 at 45 years to 500/100,000 at
around 65 years of age to reach about
750/100,000 above 75 years.
• Partial respiratory failure is associated with
hypoxia
(pO2< 60 Hgmm), global respiratory failure
with hypoxia and hypercapnia (pO2< 60 Hgmm,
pCO2>50 Hgmm).
• Typical causes of partial respiratory failure
include mild-moderate V/Q mismatch,
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