Note by dr Claudio Italiano
You have always liked to smoke, because you relaxed, you gave an intelligent tone, to Anfry Bogart in Casablanca; but now you miss the air and you are open-mouthed, grimacing so as not to make others understand that you are panting. You made a slab and the doctor shrugged! Do not worry, read and try to understand if any cure is right for you. What are we talking about? Respiratory failure, that is, you are short of breath, even for small efforts, because you have become chronic bronchitic.
When a chronic obstructive pulmonary disease begins to give problems, it is
always possible to demonstrate the presence of obstructive ventilation. Forced
breathing is related to the following pathophysiological processes:
• FEV1, that is, the air that you throw out to the first second, as well as the
vital capacity, ie the air that enters the two lungs in maximum inspiration, are
reduced compared to those normal for sex, age and height of the patient;
• the forced expiration time, ie the time necessary to forcefully expel the
entire vital capacity, is prolonged;
• the maximum speed of air flow during a forced exhalation, which depends on the
diameter of the airways, the elastic shrinking force of the lungs and the
expiratory collapse of the intrathoracic airways, is reduced. In MPOC (Chronic
Obstructive Pulmonary Disease), during normal breathing, the relationship
between pressure and respiratory flow is also altered. When the obstruction is
severe, the patient expires at maximum expiratory flow rates during ordinary
respiration. This causes a positive intrapleural pressure to occur during
expiration leading to partial (partial) airway collapse. If during the
expiration the patient squeezes the lips, the intrabronchial pressure increases
which counteracts the intrapleural positive pressure. Furthermore, maximum
expiratory flow is not achieved, so intrapleural pressure does not increase that
much. This double effect prevents the collapsing of the respiratory tract.
The capacity of retraction of the lungs decreases above all in the panlobular
emphysema. In this case, the position of respiratory rest becomes that of
inhalation and a barrel thorax develops. Residual functional capacity as well as
total capacity are increased. On the contrary, the vital capacity is reduced as
exhalation is limited. In order to exert an exhalation, the pressure in the
chest must be increased and this, in turn, causes compression and collapse of
the alveolar ducts.
In both types of emphysema, alveolar dilatation compresses the blood capillaries. This causes a reduction of the diffusion surface between blood and alveoli and an increase in functional dead space and pulmonary vascular resistance. Therefore, a pressure overload of the right ventricle is created; the consequence may be a hypertrophy of the right heart that evolving will cause a pulmonary heart.
The obstruction of the bronchioles in centrilobular emphysema causes an alteration in the distribution independent of the evolution of emphysema. There is a low partial pressure of oxygen which causes a low saturation of the hemoglobin in the blood of the pulmonary veins and, therefore, a stimulation of erythropoiesis. The combined effect of low saturation of hemoglobin and erythropoiesis results in central cyanosis. This is why patients with centrilobular emphysema are also called blue bloaters. Clinically they are classified according to the type of bronchitis.
Blue bloaters to pink puffers
In the panlobular emphysema, the alveolar surface available for gaseous exchanges is reduced. This increase in functional dead space has a physiopathological role) decisive because it obliges the patient to breathe more deeply. This allows the partial arterial pressure of the oxygen to be kept almost normal and therefore also the saturation of the hemoglobin. If the cardiac work increases, the global reduction of the diffusion surface does not cause hypoxia. The sufficient partial pressure of the oxygen and the considerable respiratory effort of the patients have dictated the denomination of pink puffers. Clinically they are classified according to the type of emphysema
Depending on the severity level of the disease, all forms ranging from mild
recurrent bronchitis to severe disability with respiratory failure can be
observed. Based on their manifestations, chronic pulmonary obstructive diseases
are very different; the clinical symptoms of emphysema mix with those of
bronchitis and give individual respiratory pictures.
If the emphysematous component predominates, there is usually a history of
several years of dyspnoea from exertion, accompanied only by poorly productive
cough with mucous sputum. The respiratory insufficiency predominates in the
objective examination: the effort produced by the accessory muscles is easily
observed and it is seen that the sternum, at the end of the inspiration, is
raised in antero-superior direction. There is tachypnea with a relatively
prolonged outflow with pursed lips. Sometimes the exhalation begins with a
snoring sound. Patients sit with the upper body tilted forward and with open
arms to lean better.
During the exhalation, the veins of the neck may appear swollen, but during the
inhalation they collapse suddenly. Body constitution is asthenic, although there
is no weight loss. The last intercostal spaces are reduced at the end of the
inspiration: at palpation one appreciates how the lower lateral thoracic wall
moves inward. At the percussion a tympanic sound is detected. The vesicular
murmure is reduced. At the end of exhalation, weak noises are heard. Heart
obtuseness is absent or frankly reduced. The heart stroke, if visible, is
observed only in the xyphoid region or below it. Often, under the xiphoid
process, it is possible to palpate a stroke of the right ventricle moved forward
and down. It is normal to hear a gallop rhythm that is accentuated in
inspiration.
If the bronchitic component predominates, an important history of cough with
expectoration that lasts a few years is almost always present in anamnesis.
Patients are often or have been chronic smokers. At the beginning the cough
appears only during the winter months and medical assistance is required only in
case of episodes of acute purulent bronchitis. Over the years the cough becomes
continuous and the bronchitis episodes last longer, they are more numerous and
more serious. The doctor's assistance is sought when the patient begins to
complain of exercise dyspnea, a sign that there is already a marked obstruction
of the respiratory tract. Sometimes the patient turns to the doctor, for the
first time, for the appearance of a right heart failure that manifests itself
with declining edema. Usually these patients are overweight and cyanotic.
Respiratory failure is rarely observed at the medical examination: the
respiratory rate is normal or only slightly increased. There is no use of
accessory muscles. At the percussion the sound is essentially clear; at the
auscultation you hear ronchi and hisses that change position and intensity after
an intense cough with expectoration. The respiratory volume per minute is normal
or only slightly increased.
The diagnosis of chronic bronchitis is essentially based on the history and can
be established only after excluding, for example, other diseases such as
bronchial carcinoma, bronchiectasis, or bronchial asthma. You can follow the
following procedure:
• medical history: ask the patient if he has had cough, sputum, respiratory
failure or if he reports a history of smoking;
• medical examination: see above;
• sputum examination: mucous or purulent in case of infection;
• lung infections: ascertain the clinical symptomatology and set up symptom
therapy;
• chest radiograph: indications;
• blood gas analysis: to be carried out especially in advanced with signs of
partial or global respiratory insufficiency.
General measures. They are independent of whether the disease has a more
emphysematous or bronchitic character and try to prevent exacerbations or
improve the patient's subjective well-being:
• Avoid irritating substances for the respiratory tract. Among these, first of
all tobacco: smoking cessation only slightly improves lung function, but avoids
the progression of damage to the lungs and bronchi;
• exercise improves the subjective sensation of well-being; it is discussed if
this also has a therapeutic effect;
• try to avoid bronchial infections. For this you need to avoid crowded places
and practice the flu shot. If an infection occurs, therapy must be started
immediately;
• in obstructive bronchitis, an abundant hydration can facilitate the
fluidification of dense secretions. Since chronic obstructive airway diseases
are associated with weight loss and general debilitation, special attention must
be paid to adequate and balanced nutrition;
• patients suffering from obstructive bronchitis must learn to breathe with
pursed lips and practice proper rehabilitative respiratory gymnastics.
Specific measures. Drug therapy serves to reduce the degree of obstruction and
to treat infections:
• the effectiveness of mucolytic drugs has not been demonstrated that diluting
the secretions should only theoretically reduce the obstructive effect, because
in fact there may be abundant secretions that the patient can not expectorate,
so that the respiratory picture can even worsen. However, some patients note
with subjective use a subjective clinical improvement;
• useful beta-agonist drugs (salbutamol, salmeterol, formetherol, etc.) have a
broncho-dilating effect and can be administered by inhalation or by oral route.
A therapy with beta-blockers should be discontinued first;
• anticholinergics (eg tiotropium spray, aclidinium bromide etc.) also have an
anti-constructive effect and can be used alone or combined with beta-agonists;
• useful use of corticones in the parenteral, oral and aerosol;
• if the aforementioned medical therapy does not improve the clinical picture,
oral theophylline can be attempted;
• as a third opportunity, oral glucocorticoids should be taken into
consideration, the dosage of which, once the therapeutic effect has been
obtained, must be scaled. In many cases they can be replaced with inhaled
glucocorticoid preparations;
• in the case of respiratory tract infection, antibiotic therapy must be started
early (see>> treatment of chronic bronchitis)
Physical measures. It is possible to strengthen the puckering of the lips by
means of special facial masks which offer a certain resistance to expiration and
which, therefore, avoid the collapsing of the respiratory tract.
Other measures. Prolonged administration with oxygen is indicated when the
partial pressure of the arterial oxygen is below 55 mmHg or below 65 mmHg in the
presence of a pulmonary heart. When there are large bubbles that compress
healthy lung tissue (infrequent condition), surgical excision is indicated. A
lung transplant should be considered when the life expectancy is less than one
year and the patient is less than 60 years old.
Emphysematous patients are less exposed than others) "bronchitic patients to recurrent respiratory tract infections. Any infection can extend to the then moni and the consequent pneumonia, in consideration of the patient's precarious immune status, can be lethal. The irreversible som emphysematous lung lesions and therefore the consequent dyspnoea can not modify it. Therapy and prognostic evaluation of patients are difficult, even if it has been shown that suitable therapy can sometimes prolong survival.
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