Gauchers News Contents
Initial instructions on infusing Cerezyme should be given in a hospital or surgery by a qualified doctor or nurse. The following are guidelines to assist those learning to infuse themselves and as a reminder once they start at home. Home infusion should only commence once the patient and helper feel confident about every aspect of the procedure.
The person to be infused should ideally not consider carrying out infusions alone as several procedures require two free hands. The infused person is restricted in movement so help should be available. Any reliable relative or friend can perform the task if properly trained but he or she should always be there when infusion takes place.
When you start home infusion by yourselves, having the phone number of a doctor or nurse is a great help if you need to ask a question or are worried about any aspect.
1-3 hours before infusion apply Emla cream to area (usually hand) where the needle will be inserted into vein. This anaethetises the area so the needle wont hurt. Children may only need the Emla cream applied one hour (or even half an hour) beforehand for it to become affective; adults may need longer. In some cases, the Emla cream may constrict the vein, making it smaller and more difficult to access. If the needle is inserted in the same place time after time, the site may toughen and the nerve endings destroyed; this will make the needle harder to push through the skin but it should hurt less. Some people find they do not need Emla cream, especially once they get used to the infusions.
The person being infused should be warm so put on an extra jumper if needed and have a hot drink beforehand. Taking a hot bath beforehand may also help. Room temperature should be 70 ° F or 22 ° C plus.
Prepare a clean surface and tray with the following items:
Prescribed number of bottles (vials) of Cerezyme (200 units in each bottle) having been stored in a fridge
Similar number of bottles of prescribed injection water
1 100ml bag of saline (plus smaller or same size bag for flushing at end)
Green topped 21mm syringe needles
1 infusion set (also known as giving set) to fix to one or two saline bags.
1 butterfly needle (plus extras if needed): type 23 (blue packet) is suitable for small veins; type 25 (orange packet) for very small veins.
Cotton wool balls.
3 strips of micropore tape (3'' long) plus scissors if needed.
2 tourniquets (1 to tighten around arm before inserting needle; 1 smaller to put around vein after infusion to stop bruising)
1 stop watch or digital watch which can time seconds.
Stand (or hook) to hang saline bag.
Sharps container (to take all discarded needles).
Make sure you have enough of everything in stock. Check expiry dates on Cerezyme bottles, injection water and saline bags and check that they contain no sediment.
Mixing Cerezyme with injection water and then saline
1. Wash and dry your hands thoroughly.
2. Flip off cap from each Cerezyme bottle taking care not to touch the top of the bottle before each one is used. If the top has been touched, clean with a pre-injection swab.
3. Unwrap syringe and green needle for syringe. Fix needle on syringe and take cover off needle. Move the plunger up and down once or twice to make it less stiff. End with plunger pushed in. Ensure the needle does not touch anything. If it does, use another needle.
4. Twist off the top of the injection water bottle and insert the needle. Draw out all the water into the syringe.
5. Hold the syringe with the needle pointing upwards and push the plunger so there is no air at the top of the syringe.
6. Then insert the needle of the syringe into bulls eye of the Cerezyme bottle. Don't push the plunger down. It will automatically go down as the vacuum in the Cerezyme bottle draws the water in. Towards the end, you can gently push down until all the water is injected into the Cerezyme.
7. Leaving the needle inserted, very gently swirl the bottle so that the powder disolves in the water. This will take about a minute. When no powder is visable, turn the bottle on its side and roll it round so that the water washes the sides and top of the bottle absorbing any powder.
8. If you are using more than one bottle of Cerezyme, repeat the procedure using a different syringe and needle. The first bottle can safely stand with the syringe remaining inserted while you deal with the other bottle(s).
9. Tear wrapping off saline bag. Do not use an already unwrapped bag as this may not be sterile, nor one where the saline is cloudy. Rest bag flat on a clean surface.
10. Taking a bottle of Cerezyme, withdraw the needle slowly until the tip of syringe needle is just level with the inside of the stopper. There is a cut out window in the stopper to see how far you can withdraw the needle. Turn the bottle upside down and suck out the Cerezyme. Pull on the plunger firmly as there is a some pressure. When all the Cerezyme is in the syringe, maintain the position of the plunger and pull the syringe from the bottle. The pressure releases as the needle comes out of the bottle.
11. Hold the syringe with the needle pointing upwards and tap the side gently to get rid of any bubbles. Do not worry if a few tiny ones remain. Push the syringe plunger so that there is no air at the top of the syringe.
12. Find hole (bulls eye) in middle of yellow stopper of the saline bag. Push the syringe needle into hole of yellow stopper. Then slowly eject Cerezyme into bag. Keep pressure on syringe until all Cerezyme is ejected and while taking syringe out.
13. After all the Cerezyme has been injected into the saline bag, slowly invert the bag twice.
Setting up Infusion Set
14. Unwrap infusion set. Then shut clamp by pushing down the roller to bottom.
15. Twist off blue stopper from port of saline bag.
16. Take cap off spike on infusion set and push straight into the port of saline bag. This can be quite stiff. Try not to twist the tube on infusion set too much while doing this.
17. Hang up infusion set on Stand provided or hook and squeeze drip chamber until it is about a quarter full.
18. Open clamp on infusion set by pushing up tap about halfway until Cerezyme reaches the far end of the tube. Then shut off by pushing tap down.
19. Any air bubbles in the infusion set tube should be expelled by tapping it so that the air escapes up towards the saline bag.
20. Tape end of tube to arm of chair where infused person will sit.
Inserting butterfly needle
The person to be infused and helper must now be involved in the following procedure.
21. Wash and dry hands thoroughly.
22. Remove Emla cream from hand and wash and dry surface. Preferably soak hand in hot (as hot as possible) water for 5 minutes to raise veins.
23. Unwrap butterfly needle. Screw off, then on again, the cap at end of butterfly tube to ensure it comes off easily.
24. Tighten tourniquet on arm. The hand should be held in a fist and rest, knuckles upwards, on the arm of a chair. This tightens the skin around the vein.
25. The person inserting the needle should feel the vein with their finger to assess the direction it is flowing. Visualise entering and progressing along the line of the vein (like sticking the needle into the inner tube of a tyre). Always insert the needle pointing towards the wrist or elbow away from the fingers. It may be easier to insert the needle at the fork junction where two veins become one.
26. Clean the skin with swab.
27. Hold the butterfly needle by its two green wings, with the open end of the needle facing upwards (and the logo showing at the top of the plastic wing). Take cover off butterfly needle but dont touch needle. If touched, use another one.
28. Insert needle as you imagined so it penetrates only about a quarter of an inch (or less) into the vein. If you are inserting the needle in your own hand, you may feel a slight sting as the needle pierces the vein; if another person is inserting the needle, they may sense a slight pop.
29. You will know that the needle is in the vein, if bloods begins to flow down the tube. The blood may only flow an inch or so down the tube and then stop. NB If no blood flows through the tube or a swelling appears at the site of the needle, see instructions 38-43.
30. Take off the cap at the end of the butterfly tube and the blood will continue to flow down the tube. If blood does not flow, see instuctions 38-43.
31. Take off the cap from the end of the infusion set and join the two tubes together when the blood has reached the end. Avoid an air gap between blood and Cerezyme.
32. Loosen tourniquet completely.
33. Secure butterfly needle to hand with microtape. You can also do this after the Cerezyme is flowing.
34. Open the clamp on the infusion set half way and regulate the speed to 10 drops every 15 seconds to give a flow of 120ml in one hour. If you wish to infuse over a longer period, eg 2 hours, regulate the speed to 5 drops every 15 seconds. Some doctors recommend 2 drops or less a second. Ask your doctor or nurse how many drops per second you should allow .
35. Check the flow rate every 10-15 minutes.
36. When the saline bag is empty, wait until the drops stop and then open clamp fully and let Cerezyme run down tube to as far as it will go. Alternatively when the bag is empty but before the chamber in the infusion set empties, replace the bag with a new saline bag and allow saline to flow through for another 6-7 minutes at the same speed. This will allow all the Cerezyme in the tube to be flushed through. Don't allow an air bubble to be created between the Cerezyme and the new saline solution; if one occurs, watch the bubble and stop the infusion before the bubble can enter the vein by shutting down the clamp. NB If you find it difficult to switch bags, you can use a y-topped infusion set which allows two bags to be fixed at the start of the infusion. You can then switch off the finished one and start the other which holds plain saline.
37. After flushing through the Cerezyme (point 36), shut the clamp on the infusion set. Then carefully remove the microtape from the skin around the needle, keeping the needle in place. Remove the needle and immediately press on with the cotton wool ball to stem bleeding. Keeping pressure on the cotton wool ball, stick down with microtape and wrap tourniquet around both to maintain pressure. Keep tourniquet on for 15 minutes. This will prevent bruising and enable frequent use of the same vein.
If difficulties with inserting butterfly needle
38. If no blood flows down the tube initially, the needle is not correctly placed in the vein. Start by changing the angle of the needle while it is still inserted as it may be hitting the side of the vein, thus stopping the blood flow through: you may need to support the needle with a little cotton wool under it to maintain the angle.
39. If this does not work, try pushing the needle further in, to the side or a little downwards or upwards; the needle may be to the side or above or below the vein.
40. If you dont wish to poke about, remove the needle. If there is no bleeding at the site, try further up the vein using a new needle. If there is bleeding, stem the flow as described in 36 and try another vein. Never use a needle more than once.
41. If blood has flowed initially but does not continue (despite removing the cap at the end of the tube) or a swelling appears, the needle may have gone through the other side of the vein. In this case, you will have to try another vein with a new needle.
42. Once the Cerezyme starts to flow into the vein, if the needle is not placed correctly, you will be left in no doubt. It will painfully sting and a swelling will rapidly appear. Do not panic but push down the clamp on the infusion set so the Cerezyme stops flowing. Remove the needle and stem the bleeding and swelling by pressing firmly with the cotton wool ball. Secure with microtape strip and tourniquet as mentioned above to prevent bruising. You will then have to try another vein with a new butterfly needle.
43. You may wish to set yourself a limit to the amount of times you attempt to insert a needle at any one session. If after three (or so) attempts, you fail and become too nervous to continue (which is understandable), keep the bag and infusion set in a cool place (preferably the fridge) and contact your doctor or nurse. It is safe to keep the mixed bag for a day or so while you sort out whether you try again yourself or ask the doctor or nurse to do it.
Gauchers News Contents
Source: Guidelines on Home Infusions. November 1998
© Copyright Gauchers Association 1998