For the short-term management of uncomplicated preterm delivery. Application to inhibit childbirth in the period from 22 to 37 weeks of pregnancy in patients without any general or obstetrical contraindications to the use of tocolytic therapy.Ad hoc application in emergency situations under certain conditions
Composition:
1 ml of solution contains 50 μg of fenoterol hydrobromide.
Action:
Sympathomimetic for stimulating β receptors2-renergic with strong tocolytic activity. After intravenous administration, fenoterol starts in a few minutes, reaches its maximum effectiveness after about 10 min and lasts for 4-8 hours. It is excreted in the form of inactive metabolites in urine and faeces. T0,5 is 6-7 hours.
Contraindications:
Hypersensitivity to fenoterol or any of the excipients. Thyrotoxicosis. Cardiac dysrhythmia with acceleration of the rhythm (tachycardia). The WPW team. Myocarditis. Mitral valve defects. Myocardial infarction. Lower vena cava compression syndrome. Glaucoma. Unsatisfied diabetes. Hypokalemia. Severe hepatic or renal failure. The use of the drug is contraindicated in the following situations: in tocolytic therapy in patients with pre-existing ischemic heart disease or in patients with significant risk factors for ischemic heart disease; in every situation occurring before the 22nd week of pregnancy; in a situation of miscarriage threatening in the 1st and 2nd trimester of pregnancy; in any condition (disease) of the mother or fetus in which prolonging pregnancy is a threat, eg severe toxemia (pregnancy poisoning), intrauterine infection, vaginal bleeding resulting from placenta previa, eclampsia or severe preeclampsia, premature separation of the placenta or umbilical pressure ; intrauterine fetal death, confirmed lethal congenital malformation or lethal chromosomal malformation. The drug is also contraindicated in any patient previously experiencing adverse effects such as pulmonary hypertension and cardiac dysfunction, such as hypertrophic cardiomyopathy with narrowing of the outflow tract or any kind of narrowing of the left ventricle outflow pathway, e.g. aortic valve stenosis.
Precautions:
During the infusion, mother's and fetal heart activity should be monitored (fetal heart activity does not change or shows slight fluctuations, mother's heart function is accelerated). The mother should also control blood pressure, potassium concentration, and in diabetic patients - in addition, the blood Glucose concentration and water balance. The drug should be used with caution in hypertension and hypotension, disorders of blood coagulation. The concomitant use of other sympathetic agents, as well as MAO inhibitors, methylxanthin should be avoided due to the increased risk of side effects in the circulatory system. The possibility of hypokalaemia should also be considered, especially when other medicines are used concomitantly, which increases the risk of heart rhythm disturbances. Any decision on the implementation of therapy with the preparation should be made after careful consideration of the risks and benefits of such treatment. Inhibition of uterine contractions with β-adrenergic agonists is not recommended after the departure of the fetal waters or when the opening of the cervix is more than 4 cm. The drug should be used cautiously to inhibit uterine contractions (tocolysis), and during the entire treatment period should be checked heart and respiratory function and ECG monitoring. The following monitoring activities must be continuous in the mother and, if possible / appropriate, in the fetus: measurement of blood pressure and heart rate, ECG, assessment of fluid and electrolyte balance (to monitor or not pulmonary edema), measurements concentrations of glucose and lactic acid (especially in diabetic patients, anti-diabetic treatment should be appropriately adjusted), measurement of potassium levels (risk of decreases in serum potassium, which increases the risk of arrhythmia).Treatment should be discontinued if the patient has signs of myocardial ischemia (such as chest pain or ECG changes). It should not be used as a tocolytic agent in patients with significant risk factors or any previous suspected heart disease (eg tachyarrhythmia, heart failure or valvular heart disease). During a premature delivery in a patient with known or suspected cardiac disease, an experienced cardiologist should assess whether the treatment is adequate before administering an intravenous infusion. Due to the risk of pulmonary edema and myocardial ischaemia, it is necessary to closely control the patient's water balance and heart and respiratory function. Patients with predisposing factors, such as multiple pregnancy, organism, maternal infection and pre-eclampsia may have an increased risk of developing pulmonary edema. Administration of the medication using an infusion pump, and not by intravenous infusion, reduces the risk of body conduction. If signs of pulmonary edema or myocardial ischemia appear in the patient, discontinuation should be considered. The infusions of β-adrenergic agonists are usually accompanied by an increase in maternal heart rate of 20-50 bpm. The mother's pulse rate should be monitored and the need to control heart rate increments by dose reduction or withdrawal should be assessed on a case-by-case basis. The maximum acceleration of the mother's pulse rate to 120 beats / min can not be exceeded. During an infusion, your maternal blood pressure may decrease slightly; the reduction concerns diastolic pressure rather than systolic pressure. The diastolic pressure is usually reduced by 10-20 mmHg. Influence of the infusion on the fetal heart rate is less pronounced, but it is possible to accelerate the heart rate by up to 20 beats / min. In order to minimize the risk of hypotension due to the use of tocolytic therapy, care should be taken to avoid compression of the vena cava (main vena cava) by keeping the patient in the left or right lateral position throughout the infusion period. In patients with hyperthyroidism, the drug should only be used with caution, after careful evaluation of the benefits and risks of treatment.
Pregnancy and lactation:
The drug can be used during pregnancy only for obstetric indications after 22 weeks of pregnancy. If delivery occurs within a short period of time after ending tocolytic treatment, the newborn may experience: tachycardia, hypoglycaemia and acid-base imbalance. Use during breastfeeding is not recommended.
In the short-term management of uncomplicated premature delivery. Administration of the drug should only be implemented by obstetricians / physicians experienced in the use of tocolytic preparations. The drug should be used in medical centers with appropriate equipment that allow continuous monitoring of the health of the mother and the fetus. Treatment should not last longer than 48 hours (the result of tocolytic therapy is postponement of labor to about 48 hours). Such a short-term postponement of delivery may be used to implement other measures to improve the child's condition in the perinatal period. The medicine should be given as early as possible after diagnosis of preterm delivery and after examination of the patient to eliminate the presence of any contraindications to the use of the drug. The test should include an appropriate assessment of the patient's cardiovascular status using cardiac and respiratory monitoring and continuous ECG monitoring throughout the treatment period. Special precautions for infusion: the dose of the drug must be selected individually, including inhibition of uterine contractions, increase in heart rate and changes in blood pressure, which are factors limiting the dosage. These parameters should be carefully monitored during treatment. The maximum mother's heart rate up to 120 beats / minute can not be exceeded. In order to avoid the risk of maternal lung edema, the most important is the strict control of fluid supply and hydration of the mother's body. Therefore, the volume of fluid in which the drug is administered should be kept as low as possible.For administration of the drug, use a controlled device for intravenous infusion, preferably an infusion pump. Preparation of the infusion solution: the contents of the ampoule (500 μg) are dissolved in 250 ml of 5% glucose or fructose solution and the concentration of 2 μg / 1 ml (20 drops) of solution is obtained. Typically, 10-30 drops / min are administered, which corresponds to a dose of 1-3 μg / min. If necessary, the dose is reduced or increased between 0.5-4 μg / min. If immediate tolicking is necessary during labor, 250 drops (12.5 ml), ie 25 μg of fenoterol, can be given intravenously over 2 to 3 minutes.
(C)
