Generality
ARDS is a rather serious medical condition, characterized by an inflammatory process affecting the lungs, which compromises the functionality of the alveoli and their ability to assimilate oxygen from the inhaled air.
Diagnosis of ARDS is based on several tests, including: physical examination, medical history, chest X-ray, chest CT scan, and so on.
Treatment includes: hospitalization in intensive care, oxygen infusion through oxygen therapy and mechanical ventilation, artificial nutrition and a series of pharmacological treatments aimed at avoiding some possible complications of ARDS.
What is ARDS?
ARDS, or respiratory distress syndrome, is a serious medical condition characterized by inflammation of the lungs and the consequent inability of the lungs to assimilate the necessary oxygen within the body.
In other words, those who suffer from ARDS have an "inflammation of the lungs, such that the latter are unable to retain, from the inhaled air, the amount of oxygen essential for good health and the proper functioning of the organs and tissues of the rest. of the body.
EPIDEMIOLOGY
According to some statistical surveys, ARDS would have an incidence on the general population of 13-23 cases per 100,000 people.
Causes
The most common causes of ARDS are:
- Sepsis. It is a life-threatening complication of a "bacterial infection, which induced an exaggerated systematic inflammatory response."
Sepsis is the most common cause of ARDS; - Inhalation of substances harmful to human health. For example, ARDS may cause breathing high concentrations of cigarette smoke or fumes from toxic chemicals;
- Accidental inhalation of vomit;
- Severe pneumonia;
- Severe flu;
- Severe trauma to the chest;
- Acute pancreatitis. Pancreatitis is the inflammation of the pancreas. A pancreatitis is called acute, when it arises suddenly, due to an equally sudden event;
- Adverse reactions to multiple blood transfusions;
- Severe burns.
PATHYSIOLOGY
Premise: inside the lungs, at the end of the respiratory tract, small characteristic sacs take place, surrounded by a dense network of blood vessels, whose specific name is pulmonary alveoli or simply alveoli.
Enclosed by a thin wall with elastic properties, the pulmonary alveoli represent the site that collects the inhaled air rich in oxygen and where the oxygen-rich assimilation takes place by the blood circulating inside the neighboring vascular network.
In withdrawing oxygen, the blood circulating all around the alveoli releases carbon dioxide (a waste product of human metabolism).
Therefore, vital oxygen-carbon dioxide gas exchange takes place in the pulmonary alveoli, culminating in the oxygenation of the blood and the exhalation of air rich in carbon dioxide.
Returning to the topic of the article in question, in ARDS the inflammation of the lungs affects the thin elastic wall of the pulmonary alveoli, compromising their integrity.
The absence of an intact alveolar wall causes the blood circulating inside the neighboring vascular network to penetrate inside the pulmonary alveoli, effectively occupying the space reserved for oxygen-rich air, coming from inspiration.
The invasion of the inside of the alveoli, by the blood, alters the functionality of the alveoli, which are no longer able to properly take in air from the outside. From this, it follows that the blood oxygenation process is insufficient to meet the needs of the whole organism.
Symptoms, signs and complications
Typical symptoms of ARDS are:
- Dyspnea (or shortness of breath)
- Abnormal increase in respiratory rate;
- Hypotension;
- Confusional state;
- Tiredness and sleepiness;
- Tendency to faint.
The intensity of these clinical manifestations varies in relation to the severity of the triggering cause: the more serious a cause, the more accentuated and evident the symptomatological picture.
WHEN DO THE SYMPTOMS APPEAR?
In most cases, the symptoms of "ARDS" begin 1-2 hours after the causal triggering event; more rarely, they appear 1-3 days later.
WHEN TO SEE THE DOCTOR?
ARDS represents a medical emergency, therefore those affected need immediate care, preferably in a hospital (as it is equipped for such eventualities).
COMPLICATIONS
In the absence of treatment and sometimes even during treatment, ARDS can give rise to various complications, some of which have a fatal outcome.
Possible complications of ARDS include:
- Pulmonary fibrosis;
- Pulmonary embolism;
- Pneumonia associated with mechanical ventilation (N.B: mechanical ventilation is a medical support for spontaneous breathing);
- Barotrauma;
- Pneumothorax;
- Memory problems, cognitive problems and / or behavioral problems;
- Acute renal failure;
- Cardiac arrhythmias;
- Myocardial dysfunctions;
- Gastrointestinal ulcers;
- Pneumoperitoneum;
- Gastrointestinal dysmotility;
- Malnutrition.
Diagnosis
Currently, there is still no specific diagnostic test for the detection of ARDS. Therefore, to accurately diagnose respiratory distress syndrome, doctors resort to various tests, some of which are also aimed at excluding pathologies with similar symptoms (differential diagnosis).
Tests for diagnosing ARDS include:
- An in-depth objective examination and, to follow, a "careful anamnesis. They allow to outline the precise symptomatological picture and to get an" idea of the probable causes.
- Oximetry. It is the test for measuring oxygen saturation in the blood. Easy and quick to perform, it requires the use of an instrument called an oximeter.
- Blood tests. They allow to identify any infectious agents in the blood. Doctors use it to figure out whether the current condition may or may not be linked to an infection.
- A chest x-ray and / or chest CT scan. They provide X-ray images of the lungs, images from which any signs of ARDS can be identified.
- An electrocardiogram and / or an echocardiogram. They are used for the differential diagnosis, to exclude or not that the symptoms in progress are due to a heart disease.
Figure: X-ray view of the lungs of a person with ARDS. Image taken from wikipedia.org
Therapy
The treatment of ARDS includes: hospitalization in intensive care, the use of therapies for raising the oxygen levels in the patient's blood, an "adequate causal therapy, artificial nutrition and, finally, an" appropriate drug therapy.
After the critical phase, ARDS also requires the adoption of a lifestyle that preserves the lungs and the organism in general from relapses.
What is intensive care?
The intensive care unit, or intensive care unit, is the hospital ward reserved for the hospitalization of patients in serious health conditions, who require continuous treatment, monitoring and support, in order to maintain their vital functions in the normal range.
THERAPIES FOR RAISING BLOOD OXYGEN LEVELS
To raise the oxygen levels in the blood of patients with ARDS, doctors use oxygen therapy and the aforementioned mechanical ventilation.
Oxygen therapy is the administration of oxygen through specific medical instruments.
CAUSAL THERAPY
By causal therapy, in medicine we mean the treatment of the causes triggering a certain morbid condition, in the hope of eliminating at the root what triggers the symptoms.
An example of causative ARDS therapy is antibiotic treatment, when the "origin of the condition" is a "bacterial infection (eg bacterial pneumonia).
ARTIFICIAL NUTRITION
In the case of ARDS, the use of artificial nutrition is essential, because patients are generally unable to feed themselves independently.
Without artificial nutrition, the patient runs the risk of falling into a state of malnutrition.
PHARMACOLOGICAL THERAPY
Aimed mostly at the prevention of complications, drug therapy for cases of ARDS can include:
- Antibiotics, to prevent infections due, for example, to mechanical ventilation. In these situations we also speak of antibiotic prophylaxis;
- Pain relievers and sedatives. Doctors administer them to all those patients who report pain;
- Anticoagulants and antiplatelet agents, to prevent the formation of dangerous blood clots;
- Medicines to reduce gastric reflux. In ARDS patients, gastric reflux can be a consequence of the long period of immobility they are forced into.
RECOMMENDED LIFESTYLE
In the case of ARDS, an adequate lifestyle strictly excludes cigarette smoking and alcohol consumption.
Prognosis
Without timely and adequate treatment, ARDS has a very high likelihood of being fatal; with appropriate treatment, the aforementioned chances decrease, but the condition in question is still serious and deserving of careful attention.
Therefore, in the presence of ARDS, the prognosis can be defined as basically negative.
MORTALITY RATE
ARDS has a mortality rate between 20 and 50%; similar percentages are to be considered high.
According to some studies, the factors that favor ARDS mortality are: the extreme severity of the triggering cause, advanced age and poor health.
