On the vial with the preparation HEMOFIL M the specific activity of factor VIII, expressed in International Units per vial, is indicated. Activity is measured in accordance with the International Standard of WHO.
Doses and duration of treatment depend on the degree of factor VIII deficiency, localization and intensity of bleeding, as well as on the clinical state of the patient.
The maximum expected level of factor VIII in vivo, expressed in IU / 100 ml of plasma or as a percentage (%), can be calculated by multiplying the single dose of the drug (in IU / kg body weight) by 2.The calculation is based on empirically obtained data that when the drug is administered at the rate of 1 ME factor VIII per kg of body weight, the level of factor VIII in plasma rises by 2 IU / 100 ml.
Example:
Dose 1750 ME, administered to a patient with a body weight of 70 kg, i.e. 25 IU / kg (1750/70), should cause an increase in the level of factor VIII to 25 x 2 = 50 IU / 100 ml, or up to 50% of the norm.
In a child weighing 40 kg, the level of activity of factor VIII, equal to 70%, can be achieved by administering a dose of 70/2 x 40 = 1400 ME.
Table of recommended dosages
The dosage should be monitored by a physician. The table can serve as an auxiliary guide.
| Bleeding |
| Severity hemorrhagic syndrome
| Activity factor VIII in plasma, necessary to achieve hemostasis (in% or in IU / 100 ml of plasma) | Frequency of administration |
| Beginning hemarthrosis, muscle hemorrhage or bleeding in the oral cavity | 20-40 | Every 12-24 hour for 1-3 days before complete relief of bleeding, which is estimated by the pain syndrome or until the wound is healed |
| Extensive hemarthrosis, muscle hemorrhage or hematoma | 30-60 | Every 12-24 hours for 3 days or more until the disappearance of pain and recovery of movements |
| Threatening life bleeding and hemorrhage: intracranial, intracavitary, bleeding from the larynx, etc.
| 60-100 | Every 8-24 hours to stop bleeding
|
| Surgical interventions |
| Small surgical interventions, incl. removal of a tooth
| 60-80 | Approximately in 70% of cases, a single injection is sufficient drug in combination with the intake of antifibrinolytic drugs inside
|
| Extensive surgical interventions
| 80-100 (before and after surgery) | Repeated injections every 8-24 hours before wound healing |
Other dosage regimens are also proposed, eg continuous maintenance therapy.
Under certain circumstances (for example, the presence of an inhibitor in low titre), doses exceeding the calculated ones may be required.
In patients with a high titer of the inhibitor to factor VIII, therapy with HEMOFIL M may not be effective, in which case other therapies should be selected.
Although the dose can be determined based on the above calculations, it is strongly recommended, where possible, conduct regular laboratory studies of plasma patient through certain time intervals in order to control the level of factor VIII in the patient.Thus, it is monitored whether the desired level of factor VIII is achieved, and whether it is maintained at a predetermined level. Particularly important is the careful monitoring of ongoing substitution therapy in cases of extensive surgical interventions or life-threatening bleeding.
Preparation of the drug solution
Observe the rules of asepsis!
1. Heat the vials with the preparation and the solvent (sterile water for injection) to room temperature.
2. Remove the protective caps from the vials with the preparation and the solvent and expose the rubber stoppers.
3. Treat the plugs with a bactericidal solution.
4. Remove the protective cap from one end of the double-sided needle and pierce the stopper of the solvent vial with this end of the needle.
5. Remove the protective cap from the other end of the double-sided needle. Turn the vial with the solvent over and quickly pierce the center of the vial with the drug with the free end of the needle. Due to the vacuum, the solvent will flow into the vial with the drug.
6. Disconnect the vials by removing the needle from the vial of the vial with the solvent, and then remove the needle from the vial with the drug. Gently shake the bottle until the drug dissolves completely.Make sure that the entire preparation is completely dissolved, otherwise it will remain on the needle filter when the solution is taken into the syringe.
NOTE: The prepared mortar must not be cooled.
Administration of the drug
Observe the rules of asepsis!
Enter intravenously at room temperature no later than 3 hours after the preparation of the solution.
Intravenous injection with a syringe
Before introduction, inspect for any discoloration or presence of mechanical inclusions in the solution. Do not use the solution in case of detection of mechanical inclusions or changes in its color. It is recommended to use plastic syringes, since with the use of preparations of this type, the inner surface of glass syringes usually becomes sticky.
1. Attach the filter needle to the disposable syringe and pull the plunger toward yourself to draw air into the syringe.
2. Insert the needle into the bottle with the prepared solution of HEMOFILA M.
3. Enter the air into the vial, and then draw the solution into the syringe.
4. Remove the needle filter from the syringe, put a suitable needle on it and enter the drug intravenously at the speed recommended further.
5. If a patient needs to enter more than one vial of Hemophil M, one can use one syringe to do this - the loss of the drug is reduced.However, the contents of each vial should be collected through a separate unused needle filter (please note that the needle filter is for the contents of only one vial!).
The rate of administration
Hemophil M can be administered at a rate of up to 10 ml / min. without significant adverse reactions.
It is strongly recommended that each time the drug is administered, register its name and serial number so that it is possible to trace the relationship of the patient's condition with the administration of the drug of a particular series.
Before and after the administration of the drug should determine the pulse rate. If the pulse rate is significantly increased, a decrease in speed or suspension of the drug administration usually allows you to quickly eliminate these symptoms.