Subcutaneous infusion is arousing a good deal of interest among
people with antibody deficiency as an alternative to intravenous
infusion. In this booklet Sister Veronica Brennan outlines the medical
background to this form of therapy and Debbie Marklew describes
how she learned to administer "subcut" therapy to her
daughter.
Many patients with primary immunodeficiency require regular replacement
therapy with Immunoglobulin (Ig). This treatment is often given
intravenously but it may also be given by rapid subcutaneous infusions
under the skin.
Subcutaneous treatment has been used extensively for some years
in Sweden and is now being used increasingly in specialist centres
in the UK. It is particularly good for young children who have very
small veins and for adults who have difficult venous access.
Immunoglobulin products and safety
As with all immunoglobulin products there is a small risk of viral
infections, but all products are strictly monitored to minimise
this risk. The benefits of the treatment in preventing life threatening
infections outweigh these risks.
For subcutaneous treatment, preservative-free immunoglobulin preparations
should be used; currently immunoglobulin produced for intramuscular
use is suitable. The solution is more concentrated than that used
for intravenous solutions and various companies are now manufacturing
products for subcutaneous use. These products are made to the same
strict specifications, with specific virus inactivation processes,
as the intravenous products.
The infusions are extremely well tolerated and give good immunoglobulin
replacement levels with a lower incidence of adverse reactions than
with intravenous preparations. Subcutaneous therapy may also give
more natural Ig levels as smaller doses are given more frequently,
thus avoiding the initial high levels given with 3 or 4 weekly intravenous
infusions.
How is the immunoglobulin given?
Immunoglobulin used for subcutaneous therapy is a more concentrated
solution than the intravenous preparations, so smaller volumes are
given. A syringe and needle are needed to draw up the immunoglobulin
from an ampoule attached to a battery operated portable pump. Two
infusions are given simultaneously through fine butterfly needles
under the skin on the abdomen, thighs or buttocks. The pump can
be strapped to the person’s body or put into a pocket.
The immunoglobulin is infused at a steady rate over one to two
hours, depending on the person's weight and the dose required (5
– 15 mls for adults). Most children can tolerate 10 mls per
site although 5 mls or 7.5mls may be given to very young children.
How often is the immunoglobulin given? .
It is quite normal to find large variations in the requirements
of patients. It may be necessary to have infusions every week, ten
days, fortnightly, every three weeks or monthly with subcutaneous
infusions. Only a small volume should be given at any one site.
When a dose increase is necessary, the frequency of infusions is
increased, and these can be given in a regime that suits the individual
patient.
How is the treatment monitored?
To make sure that the dose is correct, regular blood tests are
taken for immunoglobulin levels. Blood is also taken for liver function
tests to detect early signs of infection. The community nurse or
local doctor can take these from a finger prick at home, or from
a vein. Blood tests are usually taken every 6-8 weeks.
Home therapy
Home therapy of immunoglobulin by the subcutaneous route is available
for suitable patients. A careful assessment of the patient must
be made before he or she is accepted on a training programme, and
antibody deficient patients should be trained at a recognised training
centre where they are taught all aspects of the infusions and the
paperwork involved.
Home therapy has proved to be advantageous in saving time missed
from work and school, reducing time spent travelling to and from
hospital and by giving greater freedom and autonomy to the family.
Home infusions are considerably more cost effective to the National
Health Service and minimise the stress associated with repeated
hospital visits. Subcutaneous therapy is safe and easy to administer
and therefore an ideal treatment for home therapy.
Training
The aim of home therapy is to make the patient or family as independent
as possible and the home therapy centre will provide training in
all aspects of subcutaneous immunoglobulin infusions, including
possible adverse effects. Training for home therapy can be started
once the patient is stable on treatment.
Written instructions and a training record are given to the family.
The local community team may be invited to attend with the family
if they are unfamiliar with the treatment.
The patient or family is expected to keep written records of the
home infusions that are returned to the home therapy centre. Specialist
immunology nurses are available at these centres to monitor the
treatment and to ensure that the patient has regular medical follow-ups
with a consultant immunologist.
Community support
The community nurses and GP need to be in support of immunoglobulin
being given at home as they will be called if there are any adverse
reactions. The GP is usually asked to prescribe the treatment although
it may also be organised through the local hospital.
Adverse reactions
Adverse reactions occur more frequently during the first few infusions
but they may occur at any time. The most common cause of an adverse
reaction in a stable patient is infection, so immunoglobulin should
not be given when the patient has an infection. If the patient is
unwell, the infection should be treated with antibiotics first and
the immunoglobulin given once the temperature has settled and the
infection is under control.
There may be redness, slight swelling and some tenderness at the
site of the infusion, but these usually disappear within a few hours,
although it may take longer in people receiving larger doses. Headaches
or dizziness occasionally occur during or after an infusion, but
a paracetamol tablet often relieves the symptoms. No severe reactions
have been reported with subcutaneous infusion.
Most reactions are mild and if a reaction does occur the infusion
should be stopped. If, in the extremely rare event a severe reaction
does occur, the family is taught how to administer an Epinephrine
(Adrenaline) Epipen (an injection of adrenalin).
A Parent's View
After Holly had suffered recurring bouts of impetigo from the age
of three months, we were referred by the paediatrician at our local
hospital to Dr. Gooi, Consultant Immunologist at St. James' Hospital,
Leeds, for further tests. When Holly was nine months old, we were
told that she had CVI.
Hollys' Early Co-operation is Short-Lived
Having never heard of primary immunodeficiency before, my husband
Neil and I were thrown into utter panic. It was too much to take
in at first, but we remember being told about the two main forms
of treatment open to us - intravenous and subcutaneous - and it
all sounded fairly straightforward! Dr. Gooi thought that subcutaneous
infusions would be less traumatic for Holly because she was so young,
and also because it had proved difficult to find a vein each time
blood samples were taken.
So the weekly trips to Leeds started. At that early stage, Holly
didn't seem to mind about the infusions too much. We would put EMLA
anaesthetic cream on her tummy before leaving home so that she wouldn't
feel anything. I think it was harder for Neil and me to watch our
little girl having the infusions than it was for Holly to have them.
However, as she became a little older we realised that she wasn't
going to be so placid. Sure enough, it wasn't long before she started
to put up a fight each time we got to the hospital.
Home Therapy Training: First Catch Your Spouse…..
Around this time, Dr. Gooi suggested that we should treat Holly
at home, which meant I had to be taught how to administer the infusion.
So we started off by drawing up the gammaglobulin and setting up
the syringe driver (pump). Over the weeks this became second nature
to me, but the final obstacle was actually inserting the needle
under the skin on Holly's tummy. Each time Cathy, our nurse, asked
if I wanted to insert the needle, I would shake my head and say
no. I was petrified of doing something wrong and hurting Holly.
The worst thing was not knowing whether the EMLA really worked,
and just how much Holly could feel.
To overcome this I decided to practice on Neil at home. I put some
EMLA on his stomach, waited an hour, then stuck three needles in
him. He didn't feel anything (thankfully!). This made me feel much
better and I was able to do the whole process the next time we went
to St. James', although I must admit it was still nerve-wracking.
After three months or so of travelling 50 miles to Leeds each week,
I was eager to start treatment at home. The only thing stopping
us now was the lack of funds for the Immunology Department at St.
James' to provide us with a pump. However, the Yorkshire branch
of the PiA donated the £500 that we needed.
…Then Catch Your Toddler
Now we had everything - except Holly's co-operation! As the weeks
went by she fought us more and more. Bribery and deception had no
effect on our daughter, who at two years old had a determined mind
of her own. In the end, Dad's tender loving care and the "Lion
King" video worked wonders - and still do up to this point.
But some weeks are better than others. And who knows what the future
holds!
We always thought that, as Holly grew older, she would learn to
accept the weekly ritual and lie still for us. We still hope this
will happen one day. As it is, Neil distracts Holly with a cuddle
while I quickly insert the needle just under the skin on her tummy.
Once it is secured with some tape and we say, "That's it, Holly,
all done!" she stops struggling and expects her bribe (usually
some chocolate), as though nothing unusual has taken place. We then
put the pump into a pouch and strap it on Holly's back out of her
way. She obviously knows that the needle is there because she walks
around bent over like a little old lady, clutching her stomach,
but I know it isn't painful for her. I think she is just feeling
a little sorry for herself!
The whole process takes up to two and a quarter hours. That includes
one hour for the EMLA to take effect, 10 to 15 minutes to set up
the pump and roughly 35 to 40 minutes for the actual infusion. The
rest of the time is spent persuading Holly to let me insert the
needle.
The Conclusion: Best for Baby, Best for Parents
Neil and I believe that subcutaneous infusions are less traumatic
for Holly and much easier to administer than intravenous infusions
would be, even though it is something we have to do every week.
Being able to treat Holly at home means keeping all our lives as
near normal as possible. Also, she wouldn't be able to play and
walk around during an intravenous infusion. Instead, she would have
to sit in one place for quite a long time, which is a difficult
thing to ask of an active toddler.
We have tremendous support from Dr. Gooi and our immunology nurse,
John Toolan. And we will be forever grateful to Dr. Kate Ward, Consultant
Paediatrician at Airedale Hospital, Keighley, who first realised
that there was something wrong with Holly's immunity.
Glossary
ampoule a small glass container having one end
drawn out into a point capable of being sealed, so as to preserve
its sterile contents.
CVI or CVID common variable immunodeficiency
EMLA a local anaesthetic cream
EPIPEN an injection of adrenalin
Ig immunoglobulin
Impetigo a contagious bacterial skin disease
Intravenous inside or into a vein
subcutaneous anything relating to the loose cellular
tissue beneath the
skin
