Status asthma is the most severe manifestation of an asthma attack. It is characterized by a prolonged persistent attack of bronchial narrowing, lasting more than 3 hours and not amenable to standard therapy. The attack leads to the accumulation of carbon dioxide in the blood and the development of acute respiratory failure. There is a sharp deterioration in hemodynamic parameters with the development of inflammation and edema of the mucous membranes of small bronchi (bronchioles), leading to a violation of their drainage function and the accumulation of viscous sputum.
The reasons
Status asthma occurs in patients who have been suffering from bronchial asthma for a long time and do not follow the recommendations of the attending physician. There is a manifestation of an attack without connection with asthma – with diseases of the respiratory system (bronchitis, emphysema), Mendelssohn’s syndrome and an allergic reaction. The status can proceed in three ways:
- Metabolic – occurs as a result of bronchial damage by viral agents, an overdose of β 2 -agonists, or an exacerbation of chronic obstructive bronchitis. It is characterized by a slow, over several days, increase in the clinic of an attack of bronchial obstruction.
- Anaphylactic – an acutely developing syndrome within a few minutes. It occurs in response to repeated ingestion of allergens (antibacterial agents, local anesthetics).
- Spasmodic is the most severe type of attack. It is characterized by a sharp bronchospasm in response to the effect of irritating substances on the patient’s respiratory tract.
Triggers for Acute Progressive Respiratory Failure Syndrome in Asthma:
- exacerbation of bronchial asthma and inadequate treatment by the patient;
- the consequence of late administration of glucocorticoids in severe suffocation;
- incomplete assessment of the severity of the attack by the patient himself at home or by the treating doctor;
- untimely appeal of the patient for medical care in severe clinical manifestations of suffocation;
- improper medical tactics during the relief of an asthma attack;
- overdose of β 2 -blockers;
- the consequence of a sharp decrease in dosage or complete cancellation of glucocorticoid hormones by the patient in untreated bronchial asthma.
Manifestations
The classification of status asthmaticus is determined depending on the severity of the course of the attack in the patient:
- The stage of relative compensation. The patient’s consciousness is clear, the perception is adequate. Signs of euphoria may appear, followed by fear. The patient assumes a forced “coachman” position – a sitting position, resting his hands on a chair or bed. There is central cyanosis of the skin, increased breathing rate up to 40 movements per minute. Exhalation is difficult and impossible. When listening to the chest, dry wheezing rales are clearly audible, they can be recognized at a distance. Auscultation of the heart determines muffledness and increased frequency of sounds. The patient’s blood pressure may rise.
- Decompensation stage. The patient’s condition is assessed as serious. The patient is still conscious, but inadequately reacts to what is happening around him. Cyanosis of the body is pronounced, swelling of the veins of the neck is observed. Tachypnea – more than 40 breaths per minute. The phenomenon of “silent lung” is noted – noisy breathing is heard at a distance, but nothing is heard during auscultation. Tachycardia is pronounced (110-120 beats), the pulse is threadlike, the pressure drops. The patient’s heart sounds are barely detectable. On the electrocardiogram, signs of an overload of the right heart are typical, atrial fibrillation or other types of heart rhythm disruption are possible. There is a lack of effect from the use of bronchodilator drugs.
- Hypoxemic or hypercapnic coma. The patient’s condition at this stage of the attack is extremely difficult, there is no consciousness, but reflexes remain. Attacks of tonic and clonic seizures are characteristic. The pupils are wide, the light response is reduced. Tachypnea is replaced by bradypnea . “Silent lung” is defined in all places of the chest. The heart rate is more than 140 beats per minute, the pulse is felt only on the carotid and femoral arteries. Heart sounds are muffled. Blood pressure is reduced to numbers at which it is no longer determined. Right ventricular failure is formed. Dehydration sets in. In case of failure to provide assistance, clinical death occurs.
Diagnostics
Diagnosis of an attack should be carried out promptly and include the following actions:
- analysis of clinical features, careful collection of anamnestic data and physical examination (data of auscultation, palpation and percussion) are the most important components of a correct diagnosis at the prehospital stage;
- in the hospital, the examination is supplemented by diagnostic laboratory and instrumental methods.
Laboratory
There is only one informative method in diagnosing an attack of status asthmaticus – an analysis to determine the acid-base balance of the blood (ACB). Using it, the following indicators are determined:
- oxygen level (pronounced hypoxia);
- the amount of carbon dioxide (hypercapnia is observed);
- pH (metabolic acidosis develops).
Analysis is necessary not only to establish a diagnosis, but also to assess the severity of the condition and monitor the effectiveness of treatment of an attack.
A clinical blood test, in which a mild eosinophilia is found , a sputum study and a determination of immunoglobulin E, are of little information .
With a severe persistent asthma attack, an electrocardiogram is required, blood pressure is measured.
Differential
Differential diagnosis of status asthmaticus should be carried out with several emergency conditions – more details in the table.
Sign | Clinic | Anamnesis | Survey |
Asthmatic status |
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Cardiac pulmonary edema |
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PE (Pulmonary embolism) |
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Pneumothorax
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Auscultation – breathing is weakened or not heard on the affected side. |
General anaphylaxis |
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Contact with a potential allergen. | Auscultation and percussion are normal options. |
Foreign body |
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Auscultation and percussion are normal options. |
In childhood, when diagnosing a severe prolonged attack of bronchial asthma, it is necessary to differentiate it from acute bronchitis and pneumonia, since they proceed with signs of severe respiratory failure.
Treatment methods
Emergency care at any stage of an ongoing asthma attack requires calling the intensive care team and hospitalizing the patient in intensive care.
The algorithm for providing emergency care at the initial stage begins with the delivery of inhalations of humidified oxygen through a nasal catheter or mask. This should be done with extreme caution: instead of relieving the attack, oxygen therapy can lead to poor ventilation and respiratory arrest. For the prevention of apnea, it is better to intubate the patient and transfer to artificial lung ventilation (ALV). It is indicated in the second and third stages of suffocation.
Infusion therapy is indicated to correct metabolic disorders and restore lost fluid. The drugs are injected into a vein to control central venous pressure.
The patient’s drug treatment is to prescribe:
- glucocorticoids (Prednisolone, Methylprednisolone , Hydrocortisone, Dexamethasone );
- bronchodilators (Euphyllin, Adrenaline);
- expectorant and mucolytic enzymes (Trypsin, Chymotrypsin, Ambroxol );
- beta- adrenostimulants ( Izadrin , Alupent , Ipradol );
- antipsychotics – when excited ( Haloperidol , Droperidol ).
After stopping an acute attack in a patient, treatment of the underlying disease, bronchial asthma, is carried out.
Forecast
The mortality rate of patients from status asthmaticus is quite high. But with timely, adequate and consistent provision of qualified medical care, the prognosis is favorable. Such an attack does not pass without leaving a trace for the patient, complications may develop:
- spontaneous pneumothorax;
- pulmonary heart;
- atelectasis of the lung.
Prevention
Prevention consists in following simple rules by the patient:
- control the course of the underlying disease – asthma;
- avoid contact with allergens;
- follow the recommendations of the attending physician;
- monitor the expiration date of medicines intended for the treatment of asthma;
- for asthma, always carry an inhaler with a bronchodilator .