Intravenous
Therapy
An open learning pack for
registered nurses and midwives
Introduction
This pack has been devised to help you work at
your own pace, and to use your clinical experiences as a learning resource. It
is designed to give you a start in preparing to undertake the responsibility of
intravenous drug administration. It highlights some of the knowledge required
for practice but is in no way comprehensive.
You will need to obtain several documents to
assist you complete this study pack, and gain access to books and other
material.
1. The Trust`s Principles of Nursing
Practice.
2. Standards for Administration of
Medicines UKCC 1992.
3. Code of Professional Conduct UKCC 1992.
4. The Scope of Professional Practice UKCC
1992.
5. An up to-date British National
Formulary - BNF
6. Any of the quality texts on
pharmacology for nurses.
7. Literature from journals.
8. Guidelines for the Management of
Infection
At the end of the pack is a section entitled self
assessment, you may wish to look at this before you start in order to assess
your current level of knowledge.
How to use this pack.
In order to complete this pack you will need to
identify another nurse within your clinical area who is prepared to work with
you as a supervisor and already has expertise in this field.
The pack is divided into sections. Throughout the
pack you will come across
QUESTIONS (Q)
ACTIVITIES (A)
Spaces are left for your answers, observations or
comments. These activities may require you to 'do' something or to reflect.
Some of them require participation from your supervisor and colleagues. It is
hoped that this will promote discussion and the sharing of ideas, which will be
of mutual benefit to all parties concerned.
This pack
is not optional, it is strongly advised that you
complete all sections before you consider yourself competent to practice
independently in the administration of intravenous therapy.
You may wish to keep this pack as part of your
portfolio of personal and professional development.
Contents
Section 1. Control of infection
Section 2. Phlebitis
Section 3. Extravasation and air embolism
Section 4. Dressings
Section 5. Infusion pumps
Section 6. Central venous lines
Section 7. Risks to practitioners
Section 8. Intravenous drugs and the nurse
Section 9. The intravenous route
Section 10. Methods of IV drug administration
Section 11. Intravenous drugs and mathematics
Section 12. Professional and legal issues
Section 13. Self assessment
Section 14. Summary article and main points from Breckenridge
Learning Outcomes
Having completed this pack you will be able to;
1. Explain the need for administering I.V.
therapy.
2. State
the safe procedure for reconstituting and administering the drug and where to
find this information.
3. Recognise situations that compromise
patient safety in I.V. administration.
4. Identify and recall both the advantages
and disadvantages of I.V. drug
administration,
for -
a) Slow I.V. / bolus
injections
b) Intermittent / continuous infusion
5. Explain
practical problems which may occur in the preparation and administration of I.V. therapy, and how
these are prevented.
6. Demonstrate
competence in the calculation of IV drug dosages
7. Competently
answer all questions raised in the section "self assessment"
Section 1. Control of Infection
The 2 main sources of infection related to IV
cannulation and administration of IV therapy are the patient's skin and the
hands of the practitioner. Organisms may enter the blood stream from poor
techniques adopted when handling IV equipment or during the insertion of the
cannula. Even when the responsibility of cannulation remains with the medical
staff you are responsible for ensuring that the patient comes to no harm from
any act or omission on your part.
This may mean helping to educate/advise doctors
who are new to your ward or to IV management about appropriate measures to take
with regard to asepsis.
(Q) How is the patient's skin prepared for
cannulation on your ward?
To answer
this, you may have had to ask each cannulator on your ward/unit, and you may
have received a variety of replies! If so, what does this tell you?
* Some may or may not have used local
anaesthetic
* Some may or may not have used topical
disinfectants
* Some may or may not wear gloves
* Some may or may not shave patients
skin
* Some may or may not re-insert a
cannula if not successful on the first attempt
Any puncture of the skin, and in particular direct
access to a vein via a cannula poses a potential risk of infection.
(A) On the diagram (figure 1) indicate the
sites where the risks of contamination are
highest.
Figure
1: Potential sites for contamination
No doubt
you have identified the areas where bacteria can enter into the IV
administration set.
e.g. Portals
where giving set enters infusion bag
Portals for administration of
additives
Junction of tubing with cannula
Entry site of Cannula itself
It is essential that any contact with these sites
is made in an aseptic manner. This means that effective hand washing is
performed before handling any part of the system.
In short, effective hand washing should take place
before
* Changing
an infusion bag
* Changing
the administration set/equipment
* Changing
the dressing over the cannula
* Preparing
drugs for IV administration
* Administering
any substance IV - drugs/flush
* Removing
Cannula
(A) Observe some of your colleagues washing
their hands.
(Q) What differences did you notice?
(Q) Think about your own practice, what
prevents nurses from washing hands and how could you improve this?
Remember, it is easy to become distracted. How
often are nurses interrupted having drawn up an
injection. It is not an uncommon sight to see a nurse with a syringe in one
hand and a phone in the other.
Other essential measures to avoid introducing
bacteria include:
* Maintaining
the integrity of the administration line
* Keeping
handling of the system to a minimum
* Ensuring
the cannula site is covered and well secured to prevent movement
This entails, whenever possible, avoiding:
* The
use of connectors, bungs, hubs, taps and extension lines
* The
disconnection and reconnection of sets
(A) Examine the infusion sets used for
patients in your ward/unit.
Is each set as simple as it could be
for its purpose?
(Q) Are any "burettes" or blood
solution sets in use where "solution" only sets would suffice?
(A) If
there are any 3-way taps, connectors or additions to the basic line, find out
if they are really necessary.
(Q) What needle size is recommended by the
manufacturers of the administration sets
for giving medication by injection ports?
(Q) Why is it important to follow this
recommendation?
(Q) What precautions have been taken by the
manufacturer to ensure that the fluids
are sterile?
(Q) What do you need to check in relation to
the infusion container/fluid before
using?
Section 2. Phlebitis
Inflammation of the cannulated vein is often
associated with thrombus formation (thrombophlebitis). This common condition
may develop during or after an infusion/cannulation, and is a localised
response to infection, chemical or physical irritation. Once a clot has formed at
the cannula tip or along the wall of the vein, it becomes a focus for bacteria.
(Q) How might you recognise this condition
in an unconscious patient?
(A) Discuss with your supervisor the factors
which contribute to the development of
phlebitis (chemical, bacterial and physical).
The care of the cannula lies with the nursing
staff - communication and collaboration between nursing and medical staff is
essential for safe practice.
(Q) What measures can be taken to avoid the
administration of particulate matter ? (drugs,
rubber from vials, glass etc.).
(Examine the literature/information supplied with
administration sets).
(A) Discuss the use of filters with your
supervisor.
Section 3.
Extravasation (Tissueing) and air embolism
(Q) What happens when an IV tissues?
Perhaps the
cannula has been dislodged from the vein, or may have been inserted right
through the vein. Alternatively the vein has constricted or gone into spasm
from fluid irritation or the cannula has become dislodged from the vein, and
the fluid is running into the surrounding tissues. The site of a tissued IV is
no doubt very familiar to you and your colleagues.
(A) Observe what action is taken when an IV
slows down or stops.
(A) Consider what might happen if there is
complete occlusion, and pressure is forcefully
applied.
It is important to involve the patient in
recognising the symptoms of a 'tissued' cannula, as the infusion does not
always slow down or stop. Extravasation is a very painful condition, which is
often exacerbated by nurses trying to get the IV to flow again. The implication of certain fluids tissueing, eg. sodium bicarbonate are even more severe, as they are
necrotising agents, if accidentally infused into the tissues. Remember infusion
pumps (see section 5) may continue forcing fluid into the tissues.
(Q) What measures can be taken to minimise
the chances of tissueing occurring?
Air embolism
Another possible complication when using the
intravenous route is introduction of air into the circulation. This is
potentially fatal. No air whatsoever must be allowed to enter the vein.
(A) Think of some ways air may inadvertently
enter the bloodstream
(Q) How may these may
be prevented?
Section 4. Dressings
A simple essential measure to avoid introducing
bacteria is ensuring that the insertion site is covered. A sterile dressing may
also prevent movement of the cannula.
(Q) What are the properties of an ideal
dressing for an IV site?
(Q) What types of dressings are in use in
your unit?
Section 5. Infusion
Pumps
A pump may be used to precisely manage the
infusion rate of fluids or drugs in certain circumstances:
e.g. Critically
ill patients
Patients
receiving parentral nutrition
Patients
receiving certain drugs
The flow rate is usually set on the device in mls
per hour, but there are exceptions, some pumps for example are set to deliver a
specified number of millimetres per hour. You should always know the dose of
drug being administered per hour.
(A) Find out from your supervisor, what
types of infusion pumps are used in your unit.
(Q) For what reasons are they used?
If you are in doubt as to how to use a Syringe
Driver/Infusion Pump please seek advice from:
* A
Colleague
* The
electronics department
* The
Company direct
If you are unsure if the device is working
correctly - do not use it. Locate another device and return the faulty one to
the electronics department stating clearly the fault.
The use of an infusion pump is intended to ensure
an accurate rate of delivery, and it may also reduce the nurse's workload and
save time. However, its presence can produce a false sense of security, and
does not negate the need for regular observation of the patient, cannula site
and infusion.
Section 6. Central
Venous Lines
The use of central venous lines is increasing.
Central lines are usually inserted into one of the major veins in the neck or
chest, such as the subclavian, internal or external jugular vein.
(Q) What are the common indications for the
insertion of a central venous line?
Some of the complications of these lines are the
same as those of any IV line. However, the insertion of a central line brings
added risks.
(Q) What might be the specific risks of a
central line?
You may
have included in your list the increased seriousness of any infection,
pneumothorax, haemothorax, hydrothorax, brachial plexus injury and thoracic
duct trauma
Section 7. Risks to
practitioners
(Q) What hazards of IV therapy may harm you
or your colleagues?
(Q) What actions should be taken to prevent
these from occurring?
(Q) What actions should be taken should they
occur?
(Q) In what situations would you use gloves -
a) For
your protection?
b) For
the protection of your patient?
If you are not sure of the answers of the above
questions, ask your supervisor/ward manager, or Infection Control Specialist,
or consult the Guidelines for the Management of Infection.
In this section, some of the problems associated
with intravenous therapy have been explored. It is worth spending time looking
at the nursing practice on your unit in relation to these.
Points to Consider
* How often are
administration sets/fluids changed?
* What is the rationale for choosing a
particular dressing?
* What methods are used for
splinting/immobilising the site?
* How is the management and care of IVs
documented?
* Where are IV drugs prepared prior to
administration?
There may be more issues that you wish to
consider. It is advisable to make a note of these, so that you can discuss them
with your colleagues.
Section 8.
Intravenous Drugs and the Nurse
Listed below are some questions which a nurse
administering drugs to patients would be expected to know.
1 What therapeutic group of drug is it?
2. Why is the patient receiving this drug?
3. Is the dose appropriate for the patient
and their condition?
4. How should it be reconstituted?
5. How should it be administered, eg.
* slow IV injection (bolus) or infusion
* in what infusion fluid
* at what rate
* over what period of time
* peripherally or centrally
6. What side effects/adverse effects
should be anticipated?
7. What would you do if these effects
occurred?
If the answers to these questions are not known
for each drug, then it is the nurses responsibility to familiarise themselves
with this information before the drug is administered. Do not hesitate to ask
other colleagues:- Nurses, Doctors, Pharmacists.
Each nurse is responsible for his/her own actions
and must ensure that the patient comes to no harm from any act or omission on
their part. A nurse must not
administer drugs by the intravenous route where the instructions are unclear or
he/she has doubts concerning the safety or efficacy of the stated dose or
method of administration. The prescriber must be contacted under these
circumstances for clarification.
Section 9. The
There are three broad classes of intravenous drug
preparations:-
a) Those
presented in a form ready for administration
b) Those
which require re-constitution before administration
c) Those
which require further dilution before administration
Q. There
are a number of reasons and advantages for giving a drug by the intravenous
route, what are they?
You may have included in your list
1. The drug will have a rapid onset of
action.
2. No absorption problems will be
encountered because after intravenous
administration
100% of the dose will be in the blood stream.
3. Constant therapeutic effects can be
maintained by continuous infusion
e.g.antibiotics.
4. The patient may be nil by mouth.
5. Some drugs are ineffective by any other
route.
6. First pass metabolism is avoided.
With intravenous drugs once they are injected into
the blood 100% of the drug will reach the target organ. However with orally
administered drugs, after absorption into the blood the drug must pass through
the liver to reach the systemic circulation and target organ. In the liver the
drug may be metabolised and some drugs are so completely metabolised that only
small amounts of the administered drugs reach the target organ. This is called
first pass metabolism. First pass metabolism is one explanation as to why an
intravenous dose of some drugs is much smaller than the oral dose.
e.g. Propranolol -
after passing through the liver only about 10% of the administered oral
dose reaches the target organ. This is as a result of first pass metabolism.
Q. There are also a number of disadvantages
associated with administering a drug by
the intravenous route, what are they?
You may
have considered,
1. Higher risks of toxicity.
2. Bacterial contamination (infection) can
lead to serious complications.
3. Use of wrong dilution can cause damage
to red blood cells.
4. Allergic reactions e.g. anaphylactic
shock, are more severe.
5. Once the drug has been administered, in
most circumstances it cannot be removed.
6. Increased risk of local reactions
Section 10. Methods of
IV drug administration
Basic References for this section include:-
1. Data Sheet Compendium (current)
2. British National Formulary (current)
3.
4. Any relevant procedure manuals or other
trust protocols and policies.
The methods of administration for IV drugs are;
a) slow IV / bolus injection
b) intermittent / continuous infusion
a. Slow IV/bolus injection
Advantages
Direct
injection into line or vein therefore no cost of giving set.
Reduced
risk of infection because the drug is added at the lowest point, i.e. through
cannula rather than from higher up in the administration
set.
Reduced risk of incompatibility between various drugs because only one drug is administered at a time.
Disadvantages
High local
tissue concentration with increased risk of thrombophlebitis,
local reaction and pain.
Difficulties with administering large/small volumes over 5-10
minutes at a constant rate.
b. Intermittent/continuous infusion
Advantages
Low
local tissue concentration.
Can
titrate rate of infusion to theraputic
effect/response.
Can
stop administration before all drug given if necessary.
Accurate control of infusion rate.
Disadvantages
Increased risk of product degradation.
Increased risk of infection, through longer IV administration
system.
Increased risk of incompatibility, if more than one drug is
involved in the infusion.
Increased
cost, through use of administration set.
PRACTICAL
ASPECTS IN ADDING DRUGS TO AN INFUSION
It is important after any drug addition to mix the
solution thoroughly to ensure even
distribution of the drug. This is especially so if the drug is heavier than the
infusion solution e.g. potassium. In addition the bag should be agitated from
time to time to prevent heavier drugs layering out in the infusion bag. The
infusion container should be labelled with the name and dose of the drug, the
date and time of addition, plus the signature of the nurse adding the drug.
Full details of additives should be given on the patients intravenous infusion
therapy chart.
When using a syringe the drug should be drawn up
before the fluid vehicle to improve mixing within the syringe.
There are certain products to which drugs should not be added under any circumstances.
These include:
* Blood & blood products (e.g.
albumin, plasma)
* Amino acid solutions
* Dextrans
* TPN / lipid emulsions
* Mannitol
* Sodium bicarbonate
* Solutions containing other drugs;
unless there is information on their compatibility.
PRACTICAL
PROBLEMS IN ADDING DRUGS TO AN INFUSION
Problem 1.
Microbial contamination of the infusion solution
may occur and many infusions such as Glucose (Dextrose) 5%,
provide excellent conditions for microbial growth, particularly in warm
hospital wards. Contaminated solutions may result in pyrogenic
reactions or serious infections.
Problem 2.
Interactions may occur between the drug and the
infusion fluid or between two drugs added to the infusion fluid.
It is important to note that just because two
drugs are compatible with the same infusion solution,
it does not necessarily mean that they are compatible with each other.
For example:-
Ampicillin
sodium and Oxytetracycline hydrochloride are both compatible with Sodium
Chloride 0.9% infusion, but if added together to this infusion solution they
are incompatible.
The obvious type of interaction is the formation
of a precipitate. The precipitation may take place in the infusion container,
the drip-tubing or intravenous cannula or catheter. It may or may not be
detectable, depending on the nature of the precipitate and where it occurs. The
presence of a precipitate can cause problems:-
a) It
may block the intravenous cannula.
b) It
may damage capillaries and/or veins. It may also cause local irritation.
c) There
is a risk of embolism.
The main cause of precipitation is usually change in pH. Many injections contain drugs in the form of a
salt of sparingly soluble acid or alkaline. Additions to a solution with a
greatly different pH (that is very much more acid or alkaline) can result in a
precipitate of the free acid or alkali being formed.
For example:-
Phenytoin + Glucose 5% = decrease in pH --> precipitate
(pH 12-alkaline)
(pH4-acid)
Dobutamine +
Sodium bicarbonate = increase in pH --> precipitate
(pH 4-alkaline) (pH 8-acid)
A change in pH can also effect
the stability of the final drug solution e.g. an increase of one pH unit in an
ampicillin solution has been shown to increase the rate of decomposition.
Ampicillin + Sodium chloride 0.9% = stable for 24 hours
at room temperature
Ampicillin + Glucose 5% = Stable for 1 hour at room temperature
It is imperative to always check whether two drugs
can be added together to avoid incompatibility.
If there is no
data to recommend their addition then they should not be mixed.
There is always a pharmacist on-call, if this
information is required out of hours.
Problem 3.
The dosage of a drug added to an intravenous
infusion may become inaccurate if the rate of infusion into the vein changes.
Increase can cause toxicity, decrease can cause sub-therapeutic levels.
a) If an intravenous infusion or bolus injection
is given too fast toxicity to the patient will result.
For example, too rapid infusion of,
IV Frusemide may result in transient ototoxicity
therefore the rate should not exceed 4mg/min
IV Benzylpenicillin may result in convulsions therefore rate
should not exceed 300mg/min
IV
Phenytoin may result in symptomatic bradycardia
therefore the rate should not exceed 50mg/min
b) If an intravenous infusion is given too fast
toxicity can result again.
For example:-
Vancomycin
infusion -- flushing, hypotension, "red man
syndrome"
Amphotericin
infusion -- pain
Erythromycin
infusion -- pain.
Rapid
administration of electrolytes such as potassium chloride may cause cardiac
arrest. In other words if electrolytes are given to quickly the patient may
die.
(Q) What is meant by the term "speed
shock"?
c) If the infusion rate is too slow degradation of
the drug can occur resulting in sub therapeutic levels.
For example:-
Erythromycin
infusion must be given within 8 hours
Amphotericin
infusion must be given within 6 hours
Problem 4.
Some drugs can cause a problem by binding
onto/into plastic, eg.
INSULIN - this is absorbed into plastic and glass
such that only between 30-80% is available for use. It is advisable and good
practice to change an insulin infusion and line at least every 24 hours.
NITRATES / DIAZEPAM - these drugs absorb into
plastic/PVC.
When administering Diazepam infusion, the infusion
solution should be changed every six hours.
Nitrates are less of a problem because
administration is titrated to clinical response. However the use of specific
brands of giving sets/syringes is recommended by the manufacturer. These
devices and lines should be changed every 24 hours.
Problem 5.
Some drugs can cause problems by permeating
through the plastic into the air resulting in a loss of concentration e.g. chlormethiazole and glycerol trinitrate. However with both
drugs the dose should be titrated to patient response. It is good practice to
change giving sets and lines every 24 hours.
Problem 6.
Potassium chloride is a particularly hazardous
drug to add to infusion solutions. It is denser than most infusions, and
therefore does not mix easily. It is also cardiotoxic
in high concentrations and is a vesicant drug, (ie. may cause tissue necrosis
when extravasated). It is therefore logical to use
one of the ready prepared infusion solutions where possible. If you must add potassium to a bag make sure
it is very well mixed before administration.
If after consideration of all these points it is
deemed necessary to add a drug to an intravenous infusion, then no more than
one drug should be added at any one time to the intravenous infusion fluid,
after checking for interactions or incompatibilities.
Only in exceptional circumstances should more than
one drug be added to an infusion. In general the greater the number of
additions to an infusion fluid the greater the potential for interaction and
therefore incompatibility.
AND FINALLY
Where addition of a drug preparation to an
intravenous fluid is concerned, the most important thing to remember is:
If in doubt
- check
It is very important to remember that the wrong
drug administered by any route is dangerous. Should the wrong drug be given it
is essential that it is reported immediately to medical staff so that remedial
action can be taken.
Section 11.
Intravenous Drugs and Mathematics
Each nurse must be able to calculate drug doses
and infusion rates accurately. It is therefore essential to understand the
relevant mathematics.
For more details and further examples refer to the
book:- Gafford J D., (1991), Nursing Calculations,
3rd ed. Edinburgh, Churchill Livingstone.
Units:
1
kilogram (kg) = 1000 grams
(g)
1 gram (g) = 1000 milligrams (mg)
1 milligram (mg) = 1000 micrograms (ug)
1 microgram (mcg) = 1000 nanograms
(ng)
Always write micrograms and nanograms
in full to avoid any confusion
1 litre (L) = 1000 millilitres (ml)
Multiplication and decimal points:
To multiply by Move
the decimal place
10 1
place right
100 2
places right
1000 3
places right
Division and decimal places:
To divide by Move
the decimal place
10 1
place left
100 2
places left
1000 3
places left
INTRAVENOUS
DOSE CALCULATIONS
An essential part of this training exercise is to
be able to EXPLAIN how you reached your answer. It is also to important to
write down ALL the steps involved in obtaining the answer.
1. Convert
the following into micrograms
a)
O.5mg b) 0.25mg c) 0. 0625mg
2. Convert
the following into nanograms
a)
0.25mg b) 1.5mg c) 0.0655mg
3. Convert
the following into milligrams
a)
300 micrograms b) 75 micrograms c) 187.5 micrograms
4. Convert
the following into grams
a)
34 mg b) 518mg c) 1785mg
5. a)
You have a prescription for 10mg Pethidine. The injection strength on the ward
is 50mg/ml. What
volume would you give?
b)
Another patient has been prescribed 0.4mg Buprenorphine.
The available stock injection
is 300 micrograms/ml. What volume would you administer?
6. The
strength of Digoxin injection on the ward is 500 micrograms in 2ml. What volume would you
require for a dose of:-
a) 0.125mg b) 375 micrograms
7. Calculate
the amount of drug in milligrams (mg) in the volumes specified for the following
solutions:-
a) 10ml of a 10% solution
b) 20ml of a 0.2% solution
c) 5ml of a 20% solution
d) 100ml
of a 0.1% solution
8. You have to give a patient 0.5mg of
Adrenaline. The ward stock is 1 in 1,000.
a. What volume would you draw up? b. What volume of 1 in 10,000 would you draw
up for a 1 mg dose?
9. You
have a prescription for Dobutamine 500mg in 250ml 5%
glucose set at an infusion
rate of 10 micrograms/Kg/min. The patient weighs 50Kg. Calculate the flow rate as:-
a)
ml/hr
b) drops/min (Assume there are 20
drops/mL in this case)
10. A
patient is prescribed Lignocaine 0.4% infusion to run at a rate of 4mg/min for
30 minutes then 2mg/min for
60 minutes. Calculate the flow rate as:-
a)
ml/hr b) drops/min (Assume there are 20 drops/ml in this case)
Section 12.
Professional and Legal Issues
In preparing to undertake this new role, it is
essential that you consider your professional and legal responsibilities
alongside the practical ones. Throughout this section reference will be made to
the following documents:
UKCC (1992)
Code of Professional Conduct
UKCC (1992)
The Scope of Professional Practice
UKCC (1992)
Standards for the Administration of Medicines'
You should have copies of all these documents.
(Q) What does being accountable mean?
(A) Identify with your supervisor those
clauses in the Code of Professional
Conduct
which are relevant to the nurse administrating IV drugs
(Q) Who are we as nurses accountable to?
(Q) What are we as nurses accountable for?
Consider
the following situations:
You are
working with a Bank Nurse who says that she regularly gives IV drugs elsewhere.
Do you have any responsibility in this situation?
You are
working with a nurse who you feel is not competent to administering IV drugs to
her patient. What action would you take?
In 1992 the UKCC recognised that nursing takes
place in a context of continuing change and issued a new position statement The
Scope of Professional Practice -
(A) Read
this document now and discuss its implications with your supervisor.
(Q) Who is responsible for the
administration of IV drugs in your unit?
You will
probably find that there is no easy answer to this question. In the past
medical staff were responsible for IV administration.
(A) Discuss with a doctor in your unit who
he/she believes is/should be
responsible for the administration
of IV drugs.
Hopefully you had a useful discussion which
offered you a different perspective on this issue.
(A) Discuss with your supervisor the reasons
why nurses in your unit might
decide to administer IV drugs.
(Q) Why are you going to take on this role?
It is important to remember that because you can
administer IV Drugs, there may be occasions when you feel it would be
inappropriate to do so.
(A) Find out from your supervisor if there
have been occasions when he/she has
chosen not to administer IV drugs.
Legal Issues
The administration of IV drugs is no different
from other nursing practices. The law states that we owe our patients a
"duty of care". That is, we must ensure that no act or omission on
our part endangers the patient in any way.
There are however, a couple of points which need
specific reference.
(Q) What is Vicarious Liability?
If an employer is to accept liability for
employees, the employing authority must be aware of the practices that the
employees undertake.
(Q) How might this relate to nurses
broadening their scope of practice?
And finally,
(Q) Where can you find the rules/guide-lines
relating to drug administration in
your area?
Section 13 .
Self Assessment Excercise
1. List
the indications for using the IV route for the administration of drugs.
2. What
are the potential complications of using the IV route for the administration of
drugs?
3. Describe
the signs and symptoms of each potential complication.
4. List
the measures which help reduce the risk of infection in IV therapy
and:
a) Describe the general care required of an IV
site
b)
Identify the various items of equipment used in IV therapy on your unit.
What measures are required to ensure the safe use of each item?
5. What
information do you require before administering IV drugs in relation to:
a) The
patient
b) The
drug
6. Name
four information sources from which information about drugs can be obtained.
7. What
factors can affect the stability of drugs prepared for IV administration?
8. Under
what circumstances can incompatibility occur?
9. How
would you recognise this incompatibility?
10. What
are the signs and symptoms of anaphylaxis?
11. What
drugs most commonly cause anaphylaxis?
12. In
the event of a patient having an anaphylactic reaction what action would you
take?
13. How
do you intend to document the care of a patient undergoing IV therapy?
14. Identify
the main reasons for Nurses accepting the responsibility of IV drug
administration.
15. What
does the term "New Nursing Work" mean to you?
16. What
are your professional responsibilities with regard to New Nursing Work?
17. Describe
the limitations of professional judgement in administering IV drugs (UKCC Administration of
Medicines: Section 4)
18. If
you were asked to account for your actions in IV drug administration, how would
you demonstrate your
competence?
19. How
do you intend to document your period of 'Supervised Practice'?
Objectives,
The student
will be able to
Discuss the
principles of control of infection in theory and practice
State what
is meant by phlebitis and describe how it may be prevented
State what
is meant by extravasation and air embolism and describe how they may be
prevented
Discuss
appropriate dressings and care of a cannula
Discuss the
use of infusion pumps and calculate the rate to set them at.
Discuss the
use of central and peripheral venous lines
List the
risks to practitioners and state how each risk may be minimised
Discuss the
role of the nurse in relationship to intravenous drugs
List the
advantages and disadvantages of the intravenous route
List the
methods of IV drug administration
Competently
and accurately carry out Intravenous drug calculations and mathematics
Discuss
relevant professional and legal issues
Section 14. Summary
article and main points from Breckenridge
Introduction
In
intravenous drug therapy, drugs are administered directly into the blood stream
to achieve rapid and predictable serum levels,(1). Intravenous drugs may be
given by a bolus or continuous infusion. Primarily the difference between the
two techniques is that a bolus is given over a shorter period of time usually
via a syringe. An infusion is usually given over an 30 minutes or more, usually
via an intravenous drip or syringe driver. This article assumes that venous
access is already established.
Advantages of
intravenous therapy
Titration and
dose calculation
When
a drug is given intravenously it may be possible to observe its effect during
administration. This is because the plasma levels rise rapidly. This enables
the drug dosage to be titrated in accordance with the desired effect, therefore
ensuring the minimum therapeutic dose is administered. For example when giving
diamorphine for severe pain the injection may be stopped when the patient is
pain free, this may prevent such side effects as respiratory depression. In
addition because there is total absorption of the drug, dosages may be
accurately calculated.
Controlled
rate of administration
The
rate at which the drug is given may be carefully controlled. The use of
electronic syringe drivers allows precise control over long periods of time.
Also constant therapeutic effects can be maintained by continuous infusions, eg
antibiotics.
Emergency
situations
Rapid
speed of action if often essential in emergency situations. If an alternative
route is employed adequate serum levels may not be achieved in time to prevent
further complications or death. For example in a severe bradycardia atropine
will increase the heart rate very quickly. Also in an acute situation the
effectiveness of alternative routes may be compromised. For example in a
shocked patient a peripheral injection may be poorly absorbed due to peripheral
vasoconstriction.
Comfort
Injections
are usually painful, however with intravenous therapy, once a cannula is in
situ further injections are normally painless, this effect may be particularly
desirable in children.
Equal
distribution
Once
a drug is in the venous circulation thorough mixing of the drug in the blood
will occur thus facilitating homogeneous distribution throughout the blood.
Most
appropriate route
With
other forms of injection the volume which may be given is limited to 5mls.
However relatively large volumes may be injected intravenously, this allows for
greater dilution of potentially irritating preparations, thus preventing
inflammation and necrosis at the injection site. Patients may be given
intravenous drugs while "nil by mouth".
Possible
complications
Intravenous
therapy by-passes all barriers to drug absorption therefore speed of action is
rapid. The implication of this is that any unwanted effects may also present
equally rapidly. Once an intravenous
drug has been given it is impossible to recall, therefore possible
complications must be anticipated before they occur.
Overdose
Specific
antidotes may be given for adverse or overdose effects, eg. naloxone for opiate
overdose and flumazenil for benzodiazepines. Repeat doses of antidote may be
required as their duration of action may be shorter than that of the original
drug.
Speed shock
If
a drug is given too rapidly speed shock may occur as a result of the
accumulation of toxic concentrations in the plasma. Relatively mild symptoms
may include headache, facial flushing, chest tightness and irregular pulse(2).
More dangerous features include tachycardia, acute hypotension, syncope and the
risk of cardiac arrest. The problem should be prevented by giving intravenous
drugs slowly. If speed shock does occur the infusion is stopped and symptomatic
management given. Speed shock may also occur if an additive is not well mixed
in the intravenous infusion. Poor mixing may lead to a "layering" of
the additive due to differences in density. Potassium Chloride is particularly
prone to this problem,(3) and may cause cardiac arrest.
Allergy and
anaphylaxis
Signs
of allergy to an injected drug include generalised itching and shortness of
breath. Anaphylactic reactions are potentially life threatening and usually
present with acute hypotension and bronchospasm although there are several
other possible signs, (Table 1). Incidence of reactions may be reduced by
asking the patient about known allergies and recording these in the notes and
on the prescription sheet. If allergy or anaphylaxis is suspected the infusion
should be stopped at once. Anaphylaxis may need to be treated as an emergency
situation with intramuscular adrenalin, (Table 2)
System
disconnection
If
two parts of the administration set become disconnected the resulting drug
dosage will be inaccurate and there may be significant haemorrhage through the
open cannula.
Extravasation
The
infusion of fluids or drugs into the tissues instead of the venous circulation
is termed extravasation, (or tissueing). This occurs when a cannula is
dislodged from a vein or there is leakage between the cannula and the wall of
the vein. A study of 16,380 patients
revealed some extravasation in 22.8% of those receiving intravenous infusions,
of these 0.24% resulted in significant tissue damage,(4). The commonly
presenting features of such tissueing are localised swelling and pain. The risk
of extravasation going undetected are greater in patients who can not
communicate with their carers eg. children, the elderly and patients with
reduced states of consciousness. It is interesting to note that extravasation
occurs more frequently at night than during the day,(4).
Fluids
which are acid, alkaline, vasoconstricting, cytotoxic or hypertonic may be
particularly irritating to tissues and may cause local necrosis. Such fluids
are termed vesicant and should be monitored particularly carefully. If
extravasation occur the infusion should be stopped and medical advice taken.
The limb may be elevated to encourage lymphatic drainage and checks made for
tissue damage, impaired circulation and nerve damage.
Phlebitis
Inflammation
of a vein may occur due to infection or as a result of direct chemical
irritation from an infusion. Typically there is redness, tenderness and
swelling around the site and the vein often feels hard on palpation. There may
also be evidence of "tracking" ie. red lines running up the arm from
spreading venous or lymphatic inflammation.
If phlebitis occurs the cannula should be re-sited. The inflamed area
should be made as comfortable as possible and a medical opinion taken regarding
possible antibiotic therapy,(5). In thrombophlebitis the inflammation is
associated with thrombus formation.
Emboli
formation
Thrombosis
and air are two possible sources of emboli. No air must enter the circulatory
system. Signs of air emboli include a rapid drop in blood pressure with
tachycardia, which is potentially fatal. Air introduction should be prevented
by careful priming of all administration equipment and ensuring any connectors
are air tight.
Fluid and drug
incompatibility.
When
some chemicals are mixed they interact and may form new compounds. In addition
there is a risk of precipitate formation, which may obstruct the giving set and
form emboli. For example when phenytoin is placed in acidic dextrose solutions,
precipitation occurs. This means only solutions which are known to be
compatible may be mixed. If no specific information is available on specific
preparations they must not be mixed. If the same giving set is to be used for
administration of different compounds they should be separated by a normal
saline barrier, (6).
Bacteraemia
and Septicaemia
With
the intravenous route the normally protective lymphatics are by-passed, this
means that any infection may immediately cause bacteraemia. Bacteraemia may be
recognised by an elevated white cell count, fever, chills and a positive blood
culture. Whenever infective complications are suspected the cannula should be
removed and the tip sent for culture to optimise any antibacterial therapy.
Patients most at risk from possible infection are the elderly, the
immuno-compromised and those with existing infections.
There
are three ways a cannula may allow the entry of bacteria. Firstly by migration
along the outside of the cannula from the skin. To prevent this nurses should
wash their hands before working with an intravenous line or the area around the
entry site. Wet or contaminated dressings are an infection risk therefore the
cannula entry site should ideally be covered with a transparent dressing. This
will reduce the likelihood of outside bacterial contamination while allowing
regular inspection of the area. Good cannula stability also prevents venous
damage and possible subsequent infection. Secondly bacteria may enter the blood
via the lumen of the catheter from a breach in the giving system. The giving
system must be kept as closed as possible and the number of stopcocks or other
junctions should be minimised. The Breckenridge committee, (7) recommended
changing administration sets every 24 hours. However more recent work has suggested
changing administration sets every 48 - 72 hours is sufficient(2). All drug and
fluid containers should be checked for integrity and expiry date before use.
The risk of infection is greater in infusions with a high nutrition content
which will facilitate bacterial growth. These include, blood, plasma, dextrose
solutions, lipid emulsions and total parenteral nutrition. Thirdly as the
cannula is a foreign body it may acquire a colony of bacteria via the blood
from another site of infection.
Particulate
contamination
This
involves the injection of packaging debris such as rubber, plastic, cotton and
glass. Such foreign material is inadvertently drawn up with the drug via the
needle. Particulate contamination has been linked with lesions in the lungs, kidney,
spleen, liver and brain, (8). It has been demonstrated that a mean number of
100.6 glass particles may be aspirated from one single dose metal etched
ampoule, (9). The problems associated with such particulate contamination are
probably chronic rather than acute, so hospital based nurses may never become
aware of the subsequent problems generated. Particulates may also be
responsible for post infusion phlebitis, (6).
The
increasing use of plastic vials clearly excludes glass particle contamination
as well as preventing possible laceration of staff while opening glass
ampoules. However non glass particulate contamination has been associated with
pulmonary granulomas. Aspirating preparations with small gauge needles reduces
the number of particulates but use of filter needles or in line filters gives
the best filtering effect. Use of a 5 um filter has been found to reduce the
particulate contamination from 100.6 down to a mean of 1.3, (9). For paediatric
use a 0.22 um filter has been recommended, as bacteria are at least 0.4 um in
size these will also be removed before the infusion reaches the blood, (6).
Theoretical
considerations
Half life
This
is the time taken for half of an administered dose to be excreted; this allows
predictions in determining the duration of effect of a particular drug. It
should be remembered that in some patients half life is delayed, and if this is
not taken into consideration overdosing may occur. Half life may be extended in
the elderly, in patients with renal or hepatic insufficiency and with certain
drug combinations.
Loading dose
In
order to achieve the earliest possible therapeutic effect an initial large dose
is sometimes given followed by smaller repeat or infusion doses. For example
5000 iu of Heparin is often given by bolus injection followed by a continuous
infusion.
First pass
metabolism
This
term describes the metabolic processing of a drug in the liver when given
orally. As the gut is drained by the hepatic portal system, orally administered
drugs must pass through the liver before reaching the systemic circulation.
Some drugs may therefore be extensively metabolised. As intravenous drugs are
given directly into the systemic circulation first pass metabolism is avoided.
This is why an equivalent intravenous dose of some drugs may be less than the
oral dose. Eg. as much as 90% of a dose of Propranolol may be degraded in first
pass metabolism.
Practical
considerations
Variations in
dose
Doses
are usually given in relation to body mass, usually in mg of drug per Kg of body mass. This is clearly
vital in children and may become a factor when treating small or obese adults.
Rate of
administration
Intravenous
drugs should be given slowly. If no specific rate is prescribed a "rule of
thumb" of one ml per minute has been suggested,(1). The rate will of
course vary with the concentration of a particular drug in its dilutant and the
indication for the drug.
Infusion stops
or slows down
This
is often caused by formation of a blood clot in the lumen of the cannula. If clots
are flushed through a cannula they may lodge in the pulmonary arterial system.
Therefore if the cannula is blocked blood should be aspirated from the cannula
first,(5). This will remove any clots before the cannula is flushed with 0.9%
normal saline. However as a general rule blood should not be aspirated from a
cannula as this is associated with increased infection risk.
Diameter and
length of delivery tubing
It
is clearly essential to prime all of the delivery system. Tubing and cannula
must be flushed, usually with 0.9% normal saline, between and after
administration of each drug. It should be remembered that if a line is primed
with saline the volume of the tubing must first be infused before any of the
drug actually reaches the patient.
Using syringe
drivers
The
type of syringe drivers and protocols employed may vary from hospital to
hospital. The key is to have a unified system which minimises mathematical
calculations and the inherent scope for error they entail. For example if a 10
ml BD "luer lok" syringe is used for Heparin administration, the
preparation may be drawn up and then made up to a volume of 8 mls with normal
saline. This volume will equal 48 mm of barrel travel. This means that if the
rate on the pump is set to 2mm per hour the infusion will run through in
precisely 24 hours. In the case of insulin 48 units may be made up to 8 mls,
this will mean that there are 48 units in 48 mm, the rate in mm per hour will
therefore equal the rate in units per hour.
Giving bolus
injections
Some
drugs must never be given by intravenous bolus, eg Potassium Chloride may cause
cardiac arrest,(10). Extreme care must be taken with other electrolytes and
adrenalin. Care must be taken to ensure the only drugs given intravenously are
specified for that route, if some intramuscular preparations are given
intravenously there may be serious side effects, eg. oily preparations may form
emboli. In addition the effect of the drug may occur too rapidly eg. acute life
threatening hypoglycaemia with intravenous insulin.
Practitioner
knowledge base
As
with all drugs administered the nurse should be aware of the dose, therapeutic
and side effects, special precautions, contraindications, method of delivery
and possible nursing interventions required,(11). Appropriate antidotes and
drugs used to control side effects should be readily available. Suggested
equipment and a protocol for intravenous bolus administration are given in
tables 4 and 5.
Practitioner
safety
All
contact with preparations should be avoided as problems may occur eg.
antibiotics may cause antibody formation. Gloves and goggles may be worn if
required. When drawing up injections the pressure should be equalised inside
rubber topped vials before the needle is withdrawn to prevent aerosolization.
Glass vials should be wrapped in gauze before opening to prevent lacerations to
fingers and consequent nosocomial risk. Needles should not be re-sheathed after
use avoid needle stick injury.
Legal and
ethical aspects
Intravenous
therapy is not addressed during basic nurse education. The relevant documents
covering such practice are the Scope of Professional Practice (1992),(12) and
the Code of Professional Conduct, (1992)(13). These indicate that each
practitioner is responsible for their own practice and for keeping up to date.
In practice this usually means attending locally organised teaching sessions on
intravenous therapy followed by a period of supervised clinical practice. The
individual must have full agreement with his or her manager on the scope of their
practice.
* Shock, (acute hypotension) often
causing collapse
* Tachycardia and possible arrythmias
such as extrasystoles
* Bronchospasm
* Anxiety, agitation and distress
* Upper airway oedema with possible
laryngeal spasm
* Sneezing
* Husky voice
* Facial oedema
* Flushing and redness
* Itchy urticarial wheals
* Gastrointestinal symptoms
Table
1. Clinical features which may present in an anaphylactic reaction.
IM
adrenalin is life saving
Never give
iv except in an immediate life threatening situation slowly with 1/ 10 000 with
ECG
SC is too
slow
0.5 mg im.
Repeated
after 5 minutes if required
Some cases
require several doses
6 - 11 years give 250 mcg ie 0.25 ml 1/1
000
2 - 5 years
give 125 mcg ie 0.125
ml 1/1 000
< 2 years give 62 mcg in an increased dilution
As for
adults doses may be repeated after 5 mins if necessary
Table
2. Dosages of adrenalin by deep intramuscular injection for different age
groups used in anaphylaxis, (Resuscitation
council, consensus guidelines on anaphylaxis).
I.V.I.'S
NURSES RESPONSIBILITY
* Check infusion container for faults.
* Check prescribed fluid goes to
correct patient.
* Check I.V. line is patent.
* Inspect entry site is normal-report
if not.
* Control rate of flow as prescribed.
* Monitor condition of patient -
reporting changes.
* Maintain appropriate records.
ADDITIONAL
GUIDE-LINES
* Infusion containers should not hang
for more than 24 hours (8 hours for blood
products).
* Regular checking of entry site,
inflammation or infiltration.
* Sterile dressing covering entry site
should be changed daily at time of inspection.
FURTHER
RECOMMENDATIONS
* Use as few connections and stopcocks
as possible - keep the system closed.
* Remind doctors when a cannula has
been in place for 48 hours.
* Covering dressings should be sterile
- the entry site is an open wound.
* Ensure cannula stability.
* Removal of cannula should be aseptic
Table
3. Recommendations made by the Breckenridge Report,(7).
* Clinically clean tray
* Alcohol swabs if required
* Patients prescription chart
* Sterile needles and syringes
* 0.9% normal saline for injection
* Sharps containers
* Preparation to be injected as a bolus
Table
4. Suggested equipment for intravenous bolus injection
References
1. Burman R. Berkowity HS. (1986),
IV. bolus: effective, but potentially hazardous. Critical Care Nurse.
6(1):22-28.
2. Lamb J, (1993),
Peripheral IV therapy. Nursing Standard. 7(36):31-6.
3. British Medical
Association, Royal Pharmaceutical Society, (1994), British National Formulary.
BMA.
4. MacCara ME, (1983), Extravasation: A hazard of intravenous
therapy. Drug Intelligence and Clinical Pharmacy. 17(10):713-7.
5. Bohony J. (1993) 9 common IV complications and what to do
about them. American Journal of Nursing. 93(10):45-9.
6. Glass SM Giacoia GP, (1988), Intravenous drug therapy in premature
infants. Journal of Obstetric, Gynaecological and Neonatal Nursing.
16(5):310-8.
7. Department of Health
and Social Security, (1976), Addition of drugs to intravenous fluids. London.
DHSS. (Breckenridge report)
8. Waller DG. George
CF, (1986), Ampoules, infusions and filters. British Medical Journal.
292(6522): 714-715.
9. Sabon RL. Cheng EY Stommel KA Hennen CR, (1990), Glass particulate contamination.
Official Journal of the Canadian Intravenous Nurses. 6(2):9, 12-3.
10. Lowrey SJ Ash SR, (1988) Diminishing the risk of IV
potassium chloride. Nursing. 18(6):64.
11. Testerman EJ, (1988), IV. drug administration guidelines.
Journal of Intravenous Nursing. 11(3):188-90.
12. UKCC, (1992)
Scope of Professional Practice.
13. UKCC. (1992) Code
of Professional Conduct.
14. HMSO, London, (1990), Immunization against
Infectious Disease.
Resuscitation
Council, (1999), Emergency medical treatment of anaphylactic reactions -
Consensus Guidelines, Resuscitation 41 93-99