A hobby should be performed by a doctor who has experience in treating hemophilia.
Von Willebrand's Disease
Typically, 1 IU / kg vWF: RCo) increases the level of circulating von Willebrand factor in the blood of the patient by 0.02 IU / ml (2%).
Willebrand factor> 0.6 IU / ml (60%) and factor VIII: C> 0.4 IU / ml (40%) should be sought.
Usually to ensure hemostasis recommended administration 40-80 IU / kg vWF and 20-40 IU / kg of factor VIII per kg body weight.
It may require an initial dose of 80 IU vWF / kg, especially in patients with von Willebrand disease type 3, where maintenance of adequate levels of von Willebrand factor administration may require higher dosages than other types of von Willebrand disease.
Prevention of bleeding during surgery and serious injuries
To prevent excessive blood loss during and after operations, the drug should be administered 1 or 2 hours before the operation begins.
Every 12-24 hours, the administration of appropriate doses should be repeated.
Dose and duration of therapy depends on the clinical condition of the patient, type and severity of bleeding, and the content of von Willebrand factor and coagulation factor VIII.
When using von Willebrand factor preparations containing coagulation factor VIII, the attending physician should consider the possibility of an excessive increase in the level of factor VIII with prolonged treatment. After 24-48 hours of therapy in order to avoid an uncontrolled increase in the content of factor VIII should assess the need to reduce or increase the dose interval between dosing.
Dosage regimen in children is calculated taking into account the body weight, that is, it is based on the same principles as in adults. The frequency of drug administration should always depend on the clinical effectiveness in each individual case.
Hemophilia A
Doses and duration of substitution therapy depend on the extent, severity of the deficiency of the coagulation factor VIII, the localization and severity of bleeding, and the clinical condition of the patient.
The number of units of introduced factor VIII is measured in international units (ME), which corresponds to the current standard of the World Health Organization (WHO) for preparations containing coagulation factor VIII. The activity of factor VIII in plasma is expressed as a percentage (relative to normal human plasma) or in ME (relative to the International Standard for Factor VIII Content in Plasma).
One ME of factor VIII activity is equivalent to the amount of factor VIII in one milliliter of normal human plasma.
Calculation of the required dose of factor VIII is based on an empirically established pattern according to which 1 IU per kilogram of body weight increases the activity of factor VIII at approximately 2% of normal activity (2 IU / dl).
The required dose is calculated using the following formula:
Required number of units = body weight [kg] x required increase in factor VIII [% or IU / dL] x 0.5.
The dose and frequency of the administration should always be calculated taking into account the clinical effectiveness in each individual case.
In the event of the following bleeding, the activity of factor VIII for the relevant period should not be lower than the indicated level of plasma activity (in% of normal level or in IU / dL).
Table of calculation of doses of the drug for bleeding and in surgical practice:
Severity of bleeding / Type of surgical procedure | The required level of factor VIII (% or IU / dl) | Frequency of doses (hours) / Duration of therapy (days) |
Bleeding: |
Early hemarthrosis, muscle or mouth bleeding | 20-40 | Repeated infusion of the drug, every 12-24 hours. At least 1 day, until the bleeding stops (according to pain) or healing occurs. |
More massive bleeding, muscle bleeding or bruising | 30-60 | Repeated infusions of the drug every 12-24 hours for 3-4 days, or more, until the pain syndrome or severe disability disappears. |
Life-threatening bleeding | 60-100 | Repeated infusions every 8-24 hours to eliminate the threat to life. |
Surgery: |
Small, including tooth extraction | 30-60 | Every 24 hours, at least 1 day, until healing takes place. |
Large | 80-100 (before and after surgery) | Repeated infusions every 8-24 hours to adequate wound healing, then therapy for at least 7 days to maintain factor VIII activity at 30-60% (IU / dl). |
During the course of treatment, it is recommended to determine the level of factor VIII in order to calculate the administered dose and the frequency of infusions. With extensive surgical intervention, monitoring of substitution therapy with coagulation analysis (factor VIII activity) is mandatory. There is a significant 4 individual variability in the response to treatment with factor VIII, in vivo different recovery and half-life values are achieved.
With the long-term prophylaxis of bleeding in patients with severe hemophilia A, factor VIII is normally administered at a dose of 20-40 IU / kg with an interval of 2-3 days.
In some cases, especially in young patients, more short intervals and higher doses.
The possibility of forming antibodies (inhibitors) to factor VIII should be taken into account. It is necessary to monitor the production of factor VIII inhibitors in patients.If the expected level of factor VIII activity is not achieved with the preparation or if bleeding is stopped when the calculated dose is administered, an analysis should be carried out for the presence of factor VIII inhibitors. In patients with a high content of inhibitors, factor VIII therapy may not be effective, and alternative therapies should be considered in such cases. The management of such patients should be carried out by physicians experienced in the treatment of hemophilia patients (see also the "Special instructions" section).
Dosage regimen for children is calculated taking into account the body weight, that is, it is based on the same principles as in adults. The frequency of drug administration should always depend on the clinical effectiveness in each individual case.
Instructions for preparing a solution
General Instructions
1. The solution of the reconstituted lyophilizate ranges from clear to slightly opalescent. After filtration and before introduction it is recommended to inspect reconstituted preparation for the presence of particles and discoloration. Even instructions for dissolving are performed exactly, sometimes small solutions remain in solution flakes or particles.Device for, additions solvent with built-in the filter completely delays these particles. Filtering does not affect calculation dose. Do not use a cloudy solution or solution containing sediment (small particle) after filtration.
2. Preparation of the reconstituted solution of the preparation and the kit are carried out under aseptic conditions.
3. The unused preparation or solution of the preparation, as well as its packaging, should be disposed of in accordance with local requirements.
Preparation of the reconstituted solution
Heat the solvent to room temperature. Make sure that the caps from the bottles with the solvent and the preparation are removed, the plugs are treated with an antiseptic solution and dried before opening the device for the addition of a solvent with a built-in filter *.
1. Remove the cover from the packaging of the device for adding a solvent with a - built-in filter. Not Remove the device for adding the solvent with the built-in filter from the blister pack!
2. Place the solvent bottle on a flat, clean surface without opening it. Take the device to add solvent with a built-in filter together with a blister packing and, tightly while holding the bottle, pierce the stopper of the vial with a sharp tip of the blue part of the device, pressing vertically down.
3. Gently holding the edge of the blister pack, remove the blister pack vertically upwards from the solvent addition device. Make sure that you have removed only the blister pack, not the device itself.
4. Place a vial of the drug on a flat surface and flip a solvent vial over it with a solvent addition device attached to it. Then pierce the stopper of the vial with the core of the transparent part of the device for adding the solvent, pressing vertically downwards. The solvent will automatically move into the vial with the drug.
5. With one hand, grasp the device for adding the solvent from the side of the vial with the drug, the other from the side of the vial with the solvent and gently unfold the device in two parts, avoiding strong foaming when dissolving the lyophilizate. The solvent bottle with the blue part of the device for adding the solvent should be discarded.
6.Carefully twist the bottle with the drug and make sure that the drug is completely dissolved. Do not shake the bottle.
7. Draw air into an empty sterile syringe and, while holding the vial in the upright position, attach the syringe to the Luer tip on the solvent addition device with the built-in filter. Enter the air into the vial with the drug.
Fence and disposal of the drug:
8. By pressing the plunger of the syringe, flip the bottle together with the syringe. Slowly pulling the plunger of the syringe, put into it a reconstituted solution.
9. After the reconstituted solution is put into the syringe, grasp the syringe barrel (holding the syringe down with the piston) and detach the device for adding the solvent with the built-in filter from the syringe.
* The device for adding a solvent with a built-in filter ("Mix-2Vial ™ 20/20") is intended for single use; Do not use the device in the event of damage to the package, or after the expiry date indicated on the paper part of the blister package as follows: "EXP, year-month"
For the introduction of Hemate® P it is recommended to use disposable plastic syringes, since the solution can remain on the glass walls of the all-glass syringes.The drug should be heated to room temperature or body temperature before administration.
The drug is administered slowly intravenously at a rate that does not cause discomfort to the patient, after making sure that the blood does not enter the syringe with the drug. The reconstituted solution of the drug, drawn into the syringe, should be used immediately.
In the case where administration of large amounts of the preparation is indicated, a drip administration can be used. To do this, the reconstituted solution of the drug is added to the required volume of the infusion solution.
The rate of administration of the drug should not exceed 4 ml per minute.
If a patient experiences a reaction that may be caused by the administration of Hemate® P, it is necessary to reduce the rate of administration of the drug or to stop the administration depending on the clinical state of the patient.
The reconstituted solution remains chemically and physically stable for 48 hours at a temperature of no higher than +25 ° C. However, from the point of view of aseptic, since Hemate® P does not contain preservatives, the reconstituted drug solution should be administered immediately after dilution.Storage of the reconstituted solution should not exceed 8 hours at room temperature.