Lung diseases are quite common among pregnant women: 5-9% suffer from chronic asthma, exacerbation of asthma, together with pneumonia, gives 10% of all hospitalizations due to extragenital pathology, in 10% maternal mortality is due to pulmonary embolism.
Management and delivery of pregnant women with bronchial asthma
Bronchial asthma is a chronic inflammatory disease of the respiratory tract, manifested by their hyperreaction to certain irritants. The disease is characterized by a paroxysmal course associated with a sudden narrowing of the lumen of the bronchi and manifested by coughing, wheezing, decreased excursion of respiratory movements and an increase in respiratory rate.
Clinic. Attacks of bronchial asthma begin more often at night, lasting from several minutes to several hours. Choking is preceded by a sensation of “scratching” in the throat, sneezing, vasomotor rhinitis, chest tightness. The onset of the attack is characterized by persistent dry cough. There is a sharp difficulty in inhaling. The patient sits down, strains all the muscles of the chest, neck, shoulder girdle to exhale air. Breathing becomes noisy, wheezing, hoarse, audible from a distance. At first, breathing is quickened, then it drops to 10 per minute. The face becomes cyanotic. The skin is covered with perspiration. The chest is enlarged, almost does not shift during breathing. Percussion sound is boxed, cardiac dullness is not determined. Breathing is heard with an extended exhalation (2–3 times longer than the inspiration, and normally the exhalation should be 3–4 times shorter than the inspiration) and many dry rales of different nature. With the cessation of the attack, wheezing quickly disappears. By the end of the attack, sputum begins to separate, becoming more fluid and abundant.
Factors predisposing to the development of bronchial asthma:
upper respiratory tract infection;
medicines (aspirin,? -adrenoblockers);
occupational factors – cold air, emotional stress, exercise;
genes possibly associated with the cause of asthma are located on the 5, 6, 11, 12, 14 and 16 chromosomes and encode the affinity for IgE receptors, the production of cytokines and receptors for T-lymphocyte antigens;
etiological role of mutation of the ADAM-33 gene located on the short arm of chromosome 20 is considered.
Vital lung capacity (VC) – the maximum amount of air that can be slowly exhaled after the deepest breath.
Forced vital lung capacity (FVC) is the maximum amount of air that a person is able to exhale after the maximum breath. In this case, breathing is performed with the greatest possible force and speed.
Functional residual lung capacity is a portion of air that can be exhaled after a quiet exhalation while relaxing all respiratory muscles.
Forced expiratory volume in 1 s (FEV1) – the volume of air expelled with maximum effort from the lungs during the first second of exhalation after a deep breath, that is, part of the FVC in the first second. Normally equal to 75% of FVC.
Peak volume expiratory flow rate (PSV) is the maximum volumetric rate that a patient can develop during forced expiration. The indicator reflects airway patency at the level of the trachea and large bronchi, depending on the patient’s muscular effort. Normally, the value is 400 (380 – 550) l / min, with bronchial asthma, the indicator is 200 l / min.
The average volumetric velocity (maximum flow of the middle expiratory flow) is the forced expiratory flow rate in its middle (25–75% VF). The indicator is informative in identifying early obstructive disorders, does not depend on the patient’s effort.
Total lung capacity (OEL) is the total volume of air in the chest after maximum inhalation.
Residual lung volume (OOL) is the volume of air remaining in the lungs at the end of maximum expiration.
Changes in the respiratory system during pregnancy
During normal pregnancy, an increase in respiratory function occurs:
minute ventilation already in the first trimester increases by 40-50% from the level before pregnancy (from 7.5 l / min to 10.5 l / min), which is associated with mainly with an increase in the volume of each breath, since the frequency of respiratory movements does not change;
functional residual lung capacity is reduced by 20%;
increased ventilation leads to a decrease in the partial pressure of CO2 in arterial blood to 27 – 32 mm Hg and to an increase in the partial voltage of O2 to 95 – 105 mm Hg;
an increase in the content of carbonic anhydrase in red blood cells under the influence of progesterone facilitates the transition of CO2 and reduces PaCO2 regardless of the level of ventilation;
the resulting respiratory alkalosis leads to an increase in renal secretion of bicarbonate and its serum level decreases to 4 mU / L.
Shortness of breath is one of the most common symptoms during pregnancy:
About 70% of pregnant women report shortness of breath. Most often, dyspnea is described as “a feeling of lack of air.”
This symptom appears at the end of I – beginning of II trimester of pregnancy. The maximum period of shortness of breath during uncomplicated pregnancy is 28-31 weeks. Often shortness of breath develops spontaneously, during rest and is not associated with physical activity.
The etiology of the symptom is not entirely clear, although the effect of progesterone on ventilation is considered and a connection with a decrease in the partial pressure of CO2 in the arterial blood is traced. It was noted that shortness of breath most often develops in women who have a higher level of partial tension of CO2 outside of pregnancy.
Despite the fact that the diaphragm towards the end of pregnancy rises to 4 cm, it has no significant effect on respiratory function, because the diaphragm excursion is not broken, and even increased by 1.5 cm.
Thus, for neoslozhennoy pregnancy characterized by:
decrease in blood pCO2 ;
increase in blood pO2;
a decrease in blood HCO3 (up to 20 meq / l);
respiratory alkalosis (plasma pH 7.45);
increase in inspiration;
constancy of ZHEL.
Signs indicating pathological shortness of breath during pregnancy:
Indication of a history of bronchial asthma, even if the last attack was 5 years ago.
Oxygen saturation during exercise less than 95%.
Tachycardia and tachypnea.
The presence of cough, wheezing, obstructive pulmonary function.
Pathological data of an x-ray of lungs.
Figure 1 shows the spirogram of the forced expiratory volume in normal conditions and for various types of impaired pulmonary function. Normally, the OVF1 indicator is 75% of the FVC. With the obstructive type of spirogram, this value decreases. The total value of FVC in bronchial asthma is also less than normal. With the restrictive type of OVF1 equal to 75% of FVC, however, the FVC value is less than normal. Asthma attacks during pregnancy are not the result of ongoing gestational changes. Pregnancy does not affect the forced expiratory volume for 1 second (FEV1), the forced vital capacity of the lungs (FVC), PSV, or the average volumetric rate. Classification of bronchial asthma according to the severity of the course; Light with intermittent course: the frequency of attacks two or less times a week; seizures occur two or less nights a month; lack of symptoms between seizures. Light persistent: the frequency of seizures more than twice a week, but less than 1 time per day: seizures more than two nights a month; exacerbations cause a violation of physical activity; PSV more than 80% of the maximum for a given patient; variability over several days 20-30%; FEV1 more than 80% of the indicator outside the attack. Moderate persistent: attacks daily; symptoms occur more than one night a week; PSV, FEV1 – 60-80%, variability of more than 30%; the need for regular drug therapy. Severe persistent: attacks constantly; often attacks at night; physical activity is limited; PSV, FEV1 – less than 60%, variability more than 30%; need for regular use of corticosteroids. Bronchial asthma in pregnant women.
Bronchial asthma complicates from 5 to 9% of all pregnancies. The disease is most prevalent among women of low social status, among African Americans. In recent years, the incidence of the disease among women of childbearing age has doubled. This is one of the most common life-threatening conditions during pregnancy.
A number of factors affect bronchial asthma during pregnancy, which can both worsen and improve the course of the disease. In general, it is impossible to predict the course of asthma during pregnancy: in 1/3 of all cases, bronchial asthma improves its course during pregnancy, in 1/3 it does not change it, in 1/3 of cases bronchial asthma worsens its course: with a mild course of the disease in 13%, with moderate – 26%, with severe – in 50% of cases. As a rule, milder asthma tends to improve during pregnancy.
A pregnant woman has a risk of exacerbation of bronchial asthma, even if there has not been a single attack of the disease within the previous 5 years. Most often, exacerbations of asthma occur between 24 and 36 weeks of pregnancy, very rarely the disease worsens at a later date or at birth. The manifestation of the disease in later pregnancy is easier. In 75% of patients, 3 months after delivery, the status that was before pregnancy is returned.
Important to remember!
In pregnant women with a severe degree of the disease, respiratory tract and urinary tract infections are more common (69%) compared with mild bronchial asthma (31%) and with the general population of pregnant women (5%).
Physiological factors affecting the course of bronchial asthma during pregnancy:
an increase in the level of free cortisol in the blood counteracts the inflammatory triggers;
an increase in the concentration of bronchodilating agents (such as progesterone) can improve airway conductivity;
an increase in the concentration of bronchoconstrictors (such as prostaglandin F2?) can, on the contrary, contribute to narrowing of the bronchi;
a change in the cellular component of immunity disrupts the maternal response to infection.
Bronchial asthma and the newborn
The risk of developing asthma in the newborn varies from 6 to 30% depending on the presence of bronchial asthma in the father or the presence or absence of atopy in the mother or father.
The risk of developing bronchial asthma in a child born by large caesarean section is higher than during childbirth through the natural birth canal (RR 1.3 versus 1.0, respectively). This is due to the greater likelihood of developing atopy with the abdominal method of delivery: The
formation of the immune system occurs with the participation of the intestinal microflora. With caesarean section, there is a delayed colonization of the intestine by microorganisms.
A newborn is deprived of immunostimulating impulses in a critical period of life, he has a delay in the formation of an immune intestinal barrier.
Is a Th2 immune response (pro-inflammatory) formed with a change in the production of interleukin 10 (IL-10) and transforming growth factor? (TGF-?). This type of immune response predisposes to the development of atopic diseases, including bronchial asthma.
It is important to remember: bronchial asthma is not a contraindication to pregnancy.
Bronchial asthma and pregnancy complications
Despite the fact that an asthma attack results in a decrease in the partial oxygen tension in the mother’s blood, leading to a significant drop in the oxygen concentration in the fetal blood, which can cause fetal suffering, most women with bronchial asthma carry the pregnancy to term and give birth children with normal body weight.
There is no convincing data on the relationship of bronchial asthma and pathological pregnancy outcomes:
When using full-fledged anti-asthma therapy, an increase in the number of cases of preterm pregnancy was not detected.
The overall frequency of preterm birth in women with bronchial asthma averages 6.3%, the frequency of birth of children weighing less than 2500 g is 4.9%, which does not exceed similar indicators in the general population.
No relationship has been established between bronchial asthma and gestational diabetes, preeclampsia, chorionamnionitis, oligohydramnios, the birth of small children, and children with congenital malformations. However, women with asthma have an increased frequency of chronic hypertension.
It has been proven that the use of anti-asthma drugs -? -Agonists, inhaled corticosteroids, theophylline, cromolin-nedocromil does not worsen perinatal outcomes. Moreover, with the use of inhaled corticosteroids, the birth rate of small children in pregnant women with bronchial asthma becomes comparable to that in the general population (7.1% versus 10%, respectively).
Only with poor control of the disease, when FEV1 decreases by 20% or more from the initial one, as well as in the presence of factors predisposing to the development of vaso- and bronchoconstriction and contributing to a more severe course of the disease (autonomic nervous system dysfunction, smooth muscle anomaly), an increase in the likelihood the onset of preterm birth, the birth of hypotrophic fetuses and the development of gestational hypertension. The condition of the fetus is an indicator of the condition of the mother.
The disease with an increase in the term progresses to moderate and severe in 30% of women with a mild course of bronchial asthma at the beginning of pregnancy. Therefore, bronchial asthma of any severity is an indication for careful monitoring of respiratory function in order to identify and correct the progression of the disease in time.
It must be remembered: the key to a successful pregnancy outcome is good control of bronchial asthma.
Management of asthma during pregnancy
I. The use of objective indicators to assess the severity of the disease.
II. Patient education.
III. Control of environmental factors.
IV. Suitable drug treatment depending on the stage.
I. Indicators for assessing the severity of the disease A
subjective assessment of respiratory function, both by the patient and the doctor, is not a reliable indicator of the severity of the disease.
Determination of blood CBS is not a routine exercise, since it does not affect the management tactics of most patients.
FEV1 measurement is the best method for assessing respiratory function, but requires spirometry. An indicator of less than 1 liter or less than 20% of the norm indicates a severe course of the disease.
PSV is close in accuracy to FEV1, but its measurement is more accessible with the advent of inexpensive portable peak flow meters and can be performed by the patient. In normal pregnancy, the PSV value does not change.
II. Patient training
Before pregnancy, a patient with asthma should be informed of the following:
Triggers for developing an asthma attack (allergens, upper respiratory infections, taking aspirin,? -Adrenergic blockers, cold air, emotional stress, exercise) should be avoided.
The patient should be trained to measure PSV twice a day for early detection of respiratory dysfunction. Measurements are recommended immediately after waking up and after 12 hours.
The patient should have a suitable inhaler. The use of a spacer (nebulizer) is recommended to improve the dispersion of the drug in the lungs and reduce the local effect of steroids on the oral mucosa, reduce absorption through it and minimize the systemic effect.
All pregnant women should have a written management plan, which should indicate the medications necessary for the patient in accordance with PSV and contain recommendations for reducing this indicator:
the maximum PSV value for the patient is taken as the basis. The patient should be informed about “step-by-step therapy” with a transient decrease in PSV by 20% from this level;
it is necessary to indicate to the pregnant woman that with a prolonged decrease in PSV by more than 20%, it is necessary to contact a doctor;
drop in PSV by more than 50% of the maximum level for the patient – an indication for hospitalization in the intensive care unit.
It is necessary for patients to explain that pregnancy outcomes worsen only with poor control of bronchial asthma: the
patient should not stop taking medications if pregnancy is established;
preparations and doses should be the same both outside of pregnancy and during it;
during pregnancy, inhalation forms of drug administration should be preferred in order to reduce the systemic effect and effects on the fetus.
III. Monitoring environmental factors
Reducing the effects of allergens and irritants can reduce the amount of medication taken to control asthma and prevent exacerbations.
Approximately 75-85% of patients with asthma have positive skin tests for allergens: animal hair, dust mites, cockroach waste products, pollen and mold.
It is necessary to reduce the effects of indoor allergens – house dust and animal hair: remove the carpet from the bedroom, use a mite-tight mattress, use a pillowcase, wash bedding and curtains with hot water, and remove dust accumulation.
If you are allergic to pet dust, they should be removed from the house. If this is not possible, then animals should not be allowed into the bedroom, it is also necessary to remove the carpet from the bedroom and place a highly efficient air filter system in it.
Irritants such as active and passive smoking can also be factors that worsen the course of asthma. They should be excluded to avoid disease progression.
Other non-immune factors that trigger an asthma attack should be taken into account: strong aromas, air pollution, physical activity, food additives (sulfites), medications (aspirin,? -Blockers).
IV. Drug treatment
A. Even if the above recommendations are followed, most patients still need medical support.
All drugs used in AD are classified as B or C according to the FDA classification (US Drug and Food Administration). Unfortunately, these categories cannot fully guarantee the safety of drugs. In each case, it is necessary to carefully evaluate the “benefit-risk” relationship and inform the patient about this.
Studies of medicines for the treatment of asthma in humans have not revealed drugs that significantly increase the risk of fetal malformations.
B. Preparations for the treatment of bronchial asthma are divided into symptomatic drugs (? -Agonists and ipratropium, which are used in intensive care units) and drugs for maintenance therapy (inhaled and systemic corticosteroids, leukotriene antagonists, cromolin).
Preparations for symptomatic treatment are used in emergency cases. They relieve acute bronchospasm, but do not affect the underlying inflammatory process.
? 2 short-acting agonists [albuterol (Ventolin), isoproterenol, isoetarin, biltolterol, pirbuterol, metaproterenol, terbutaline]. These drugs are considered safe when inhaled. The most studied during pregnancy is albuterol. It is preferred for the relief of acute symptoms of the disease. The drug has been used in many millions of patients worldwide and in several thousand pregnant women. However, no data on any teratogenic effect were obtained. With inhalation use, the systemic effect of albuterol is minimal. The second most studied drug during pregnancy from this group is metaproterenol.
? 2 long acting agonists (salmeterol). The data obtained in pregnant women is not enough to draw a conclusion about teratogenicity for humans. Despite the fact that this drug is considered safe when inhaled, it should only be used if beclomethasone and / or cromolin are ineffective. Perhaps the combined use of salmeterol with inhaled corticosteroids or cromolyn for persistent asthma, however, there is insufficient data on the benefits of such a treatment regimen.
Remember: recent studies have shown an increase in mortality from asthma due to the use of? 2 long-acting agonists. It follows that these drugs should not be used as monotherapy for asthma, but should be combined with adequate doses of inhaled corticosteroids.
Inhaled anticholinergics [ipratropium (Atrovent)]. Recent studies have shown that ipratropium can enhance the bronchodilatory effect of? -Agonists in the management of an acute asthma attack. This allows you to actively use the drug in a short course in the intensive care unit. The absence of a teratogenic effect in ipratropium was confirmed by animal data, but there are insufficient data on pregnant women. When inhaled, the drug is poorly absorbed by the mucosa of the bronchial tree and, therefore, has a minimal effect on the fetus.
Preparations for maintenance therapy. Supportive therapy drugs control airway hyperreactivity, that is, they remove the inflammatory process that underlies this hyperreactivity.
Inhaled corticosteroids (IR) reduce the risk of attacks, the frequency of hospitalization (80%) and improve pulmonary function.
The most important drugs in the supportive treatment of asthma, both outside and during pregnancy: only 4% of pregnant women who received IR from the initial stages of pregnancy developed an acute attack of the disease, of those who did not receive IR, such an attack occurred in 17%.
Inhaled corticosteroids differ in the duration of their effect: short-acting – beclomethasone, medium-triamcinolone, long-term – fluticasone, budesonide, flunisolid.
When inhaled, only a small part of the drugs is adsorbed, and they do not have a teratogenic effect.
In 20% of cases, more than 1 drug of this group is used.
Beclomethasone is the most commonly used IR in bronchial asthma during pregnancy. The use of beclomethasone and budesonide is considered preferable due to the fact that their effect has been most fully studied during pregnancy.
Triamcinolone is also not considered teratogenic, although the number of observations on its use during pregnancy is less.
Fluticasone has not been studied during pregnancy, however, the minimal absorption after inhalation and the safety of other IRs make its use warranted.
Mast cell stabilizers (MTC) – cromolyn, nedocromil – is best used for mild asthma, when it is decided not to use IR. For the treatment of asthma attacks are not used. Data obtained from pregnant women and animals indicate a lack of teratogenicity in these drugs. They are not absorbed through the mucosa and the part that got into the stomach is excreted with feces. It is believed that during pregnancy, it is preferable to use cromoline.
Leukotriene (AL) antagonists have now begun to play a more significant role in disease control, especially in adults. For the treatment of asthma attacks are not used. Zafirlukast, Montelukast and Zileuton. The use of AL during pregnancy, due to insufficient data on their safety for humans, is limited to those cases where there is evidence of good control of the disease with these drugs before pregnancy, and control cannot be achieved by other groups of drugs.
Continuously released methylxanthines. Theophylline is an intravenous form of aminophylline; it is not a teratogen for humans. The safety of this drug has been demonstrated in pregnant women in the II and III trimesters. The metabolism of the drug undergoes changes during pregnancy, therefore, in order to select the optimal dose , its concentration in the blood (8-12 μg / ml) should be evaluated. Theophylline refers to medications of the 2-3 line in the treatment of bronchial asthma, its use is not effective in an acute attack of the disease.
Systemic corticosteroids (SC) (oral – prednisone; intravenously – methylprednisolone, hydrocortisone) are necessary in the treatment of severe asthma.
Most studies suggest that systemic corticosteroids do not pose a teratogenic risk to humans. Prednisolone and hydrocortisone do not cross the placenta, because destroyed by its enzymes. Even at high blood concentrations, the effects of prednisone or hydrocortisone on the hypothalamic-pituitary-adrenal axis of the fetus are minimal.
An increase in the frequency of the cleft of the upper lip and palate was shown when taking systemic corticosteroids, starting from the 1st trimester, by 2-3 times. With inhaled forms of administration, such an increase was not noted.
When taking SC in the first trimester, when it is justified by vital indications, the patient must be informed about the risk of developing a cleft of the upper lip and palate in the fetus.
When introduced in the II and III trimesters, SCs are not the cause of malformations in the fetus.
Betamethasone and dexamethasone cross the hematoplacental barrier. There is evidence that more than two courses of corticosteroids for antenatal prophylaxis of respiratory distress syndrome may be associated with an increased risk of damage to the brain of a premature fetus. The patient should be informed about this if there is a need for the introduction of large doses of corticosteroids in late pregnancy.
Specific immunotherapy with allergens is the gradual administration of increasing doses of the allergen in order to weaken the body’s response to the next contact with it. This method of therapy can provoke an anaphylactic reaction and is not used during pregnancy.
Therapy of bronchial asthma during pregnancy, depending on the stage of the disease
Mild with intermittent course:
if necessary, use of? 2-adrenergic agonists;
there is no need for daily medication.
Use if necessary? 2-adrenergic agonists.
Daily Reception Preferably: low doses of inhaled corticosteroids (beclomethasone or budesonide).
Alternative: cromolin / nedocromil, or leukotriene receptor antagonists, or prolonged theophylline (maintaining a serum concentration of 5-15 μg / ml).
Use if necessary? 2-adrenergic agonists.
Daily Reception Preferably: low and medium doses of inhaled corticosteroids in combination with long-acting beta2 agonists.
Alternative: medium doses of inhaled corticosteroids; or low and medium doses of inhaled corticosteroids plus leukotriene receptor antagonists (or theophylline in nocturnal attacks).
Use if necessary? 2-adrenergic agonists.
Daily intake: high doses of long-acting inhaled corticosteroids and? 2 agonists (salmeterol), or high doses of IR with aminophylline preparations, as well as daily or less frequent use of systemic steroids (prednisone).
Indications for hospitalization of the patient are: a
steady drop in PSV by less than 50-60% of the maximum value for the patient;
pO2 reduction of less than 70 mm Hg;
increase in pCO2 more than 35 mm Hg;
Heart rate of more than 120 per minute;
respiratory rate of more than 22 per minute.
It is important to remember: an
increase in pCO2 in a pregnant woman with an asthma attack of more than 40 mm Hg indicates increasing respiratory failure, since normal pCO2 values during pregnancy range from 27 to 32 mm Hg.
unfavorable prognostic signs in bronchial asthma are circadian variations in pulmonary function, a pronounced reaction to bronchodilators, the use of three or more drugs, frequent hospitalizations in the intensive care unit and a life-threatening history.
in the absence of the effect of the “step-by-step therapy”, an asthmatic status develops (status asthmaticus) – a state of severe asphyxia (hypoxia and hypercapnia with decompensated acidosis), which does not stop by conventional means for many hours or several days, sometimes leading to the development of hypoxic coma and death (0.2% of all pregnant women with bronchial asthma). A protracted asthma attack is an indication for hospitalizing a patient in an intensive care unit.
Management of an asthma attack in the intensive care unit: The
treatment for an asthma attack during pregnancy is the same as outside pregnancy.
Oxygen supply until saturation (SO2) is achieved not less than 95%, PaO2 more than 60 mm Hg.
Prevent an increase in pCO2 over 40 mm Hg.
Avoid hypotension: the pregnant woman should be in the position on the left side, adequate hydration is necessary (drinking, iv administration of the isotonic solution at a rate of 125 ml / hour).
Administration of? 2 agonists in inhaled forms until effect or toxicity is achieved: albuterol (metered dose inhaler with nebulizer) 3-4 doses or albuterol nebulizer every 10-20 minutes.
Methylprednisolone 125 mg intravenously rapidly, then 40-60 mg intravenously every 6 hours, or hydrocortisone 60-80 mg intravenously every 6 hours. After improvement, transfer to tablet prednisone (usually 60 mg / day) with a gradual decrease and complete withdrawal within 2 weeks.
Consider administering ipratropium (atrovent) in a metered dose inhaler (2 doses of 18 mg / spray every 6 hours) or a nebulizer (62.5 ml vial / nebulizer every 6 hours) in the first 24 hours after the attack.
Do not use epinephrine subcutaneously in pregnant women.
Timely resolve the issue of tracheal intubation: weakness, impaired consciousness, cyanosis, growth of pCO2 and hypoxemia.
Monitoring of lung function by measuring FEV1 or PSV, constant pulse oximetry and CTG of the fetus.
No panic! An acute asthma attack is not an indication for labor induction, although the issue of induction of labor must be considered in the presence of other pathological conditions in the mother and fetus.
Recommendations for the management of pregnant women with bronchial asthma:
ensuring optimal control of the disease during pregnancy;
more aggressive than non-pregnant, management of asthma attacks;
avoid delay in diagnosing and starting treatment;
timely assess the need for drug therapy and its effectiveness;
providing a pregnant woman with information about her disease and teaching her the principles of self-help;
adequate treatment of rhinitis, gastric reflux and other conditions that trigger an asthma attack;
promotion of smoking cessation;
spirometry and determination of PSV at least 1 time per month;
refusal of influenza vaccination before 12 weeks of pregnancy.
Management of labor in patients with asthma Asthma
exacerbations during childbirth are quite rare. This is due to physiological birth stress, in which there is a release of endogenous steroids and epinephrine, which prevent the development of an attack. Choking that occurred at this time, it is necessary to differentiate from pulmonary edema with heart defects, preeclampsia, massive tocolysis and septic state, as well as from pulmonary embolism and aspiration syndrome.
It is important to maintain adequate oxygenation and hydration, to control oxygen saturation, the function of external respiration, and to use those drugs that were used to treat asthma during pregnancy.
Prostaglandins E1, E2 and oxytocin are safe in patients with bronchial asthma.
Prostaglandin 15-methyl F2 ?, ergonovin and other ergot alkaloids can cause bronchospasm and should not be used in these pregnant women. The bronchospastic effect of the ergot alkaloids group is potentiated by drugs for general anesthesia.
Theoretically, spasm of the bronchi can cause morphine and meperidine, since histamine is released from mast cell granules, but this practically does not happen. A large number of women receive morphine-like drugs in childbirth without any complications. However, a number of experts believe that in women with bronchial asthma, it is preferable to use butorphanol or fentanyl, since they are less likely to contribute to the release of histamine.
If necessary, anesthesia is preferred epidural, since general anesthesia is associated with a risk of chest infection and atelectasis. Epidural anesthesia reduces the intensity of bronchospasm, reduces oxygen consumption and minute ventilation. Despite the fact that conducting general anesthesia in the form of intubation anesthesia is extremely undesirable, drugs with a bronchodilating effect – ketamine and halogenates – are preferred.
Daily doses of systemic steroids received by the patient for several weeks suppress the hypothalamic-pituitary-adrenal interaction over the next year. This weakens the physiological release of adrenal corticosteroids in stressful situations (surgery, labor).
In order to prevent the adrenal crisis in childbirth, an empirical prescription of glucocorticoids is proposed for women who have received SK therapy for at least 2-4 weeks during the last year. Some authors believe that such therapy should be carried out if these drugs were not canceled a month before birth.
If the prophylactic administration of glucocorticoids was not carried out in childbirth, in the postpartum period it is necessary to monitor the appearance of symptoms of adrenal insufficiency – anorexia, nausea, vomiting, weakness, hypotension, hyponatremia and hyperkalemia.
Recommended use of glucocorticoids in childbirth: hydrocortisone 100 mg iv every 8 hours on the day of birth and 50 mg iv every 8 hours on the day after delivery. Next – the transition to supporting oral medications with the gradual withdrawal.
Remember! The risk of exacerbation of asthma after cesarean section is 18 times higher in comparison with vaginal delivery.
The postpartum period is
not associated with an increased frequency of exacerbations of bronchial asthma;
patients should use those medications that are necessary in accordance with PSV, when measured on the first day after birth;
breathing exercises are recommended;
breastfeeding is not contraindicated when taking any anti – asthma drugs;
breastfeeding for 1-6 months after birth reduces the risk of developing atopy in adolescents at 17 years of age by 30-50%.