Incorrectly administered vaccines, either incorrect sites or poor administration techniques, are contributing factors to vaccine failure and can lead to injection site nodules or lumps and local reactions.
Proper knowledge of vaccine administration is very important for the vaccine provider and regular vaccine administration training programme should be held by the government or NGO bodies.
- Diphtheria, Tetanus, Pertussis, (DPT) Haemophilus Influenzae Type B (HIB), Hepatitis A and Hepatitis B components must be injected deep intramuscularly (IM)
- BCG is delivered intradermally
- MMR, measles IPV are injected subcutaneously (S/C)
- OPV and Rotavirus vaccines are given orally.
- Check the datasheet for administration of other vaccines
Drawing up the vaccine in syringe.
- Check the colour and appearance of the vaccine for indications of vaccine damage (sediment or colour change).
- Vaccines contain adjuvants, stabilisers and preservatives and therefore must be shaken vigorously before drawing up to obtain uniform suspension.
- Expel air from the syringe until vaccine is visible at the needle connection part of the syringe. Check the vaccine volume in the syringes, as the vial is usually overfilled.
Length and gauge of the needle;
- Most vaccines are given via the intramuscular route into the deltoid or the lateral aspect of the thigh. This optimizes the immunogenicity of the vaccine and minimizes adverse reactions at the injection site.
- Injecting a vaccine into the layer of subcutaneous fat, where poor vascularity may result in slow mobilization and processing of antigen, is a cause of vaccine failure.
- Skin preparation or cleansing the injection site prior to vaccination is not necessary. However, if an alcohol swab is used the area needs to be cleaned for >30 seconds and it must be allowed to dry (at least 2 minutes), otherwise alcohol may be tracked into the muscle causing local irritation.
- Alcohol may also inactivate a live attenuated vaccines.
The injectable vaccines should be administered in a site (healthy well-developed muscle) that is as free as possible from the risk of local, neural, vascular and tissue injury.
Ø Vastus Lateralis
For IM injections in infants under 15 months of age, the recommended and safest site is the Vastus Lateralis (antero-lateral aspect of the thigh). An infant can be placed lying on their back on the bed or in the cuddle position on the parents/caregivers lap. Use of the anterior thigh or rectus femoris muscle is not recommended because what appears to be a bulky muscle anteriorly is predominantly subcutaneous fat. Immediately underlying the rectus femoris muscle is a neurovascular bundle. Vaccine deposition within the neurovascular bundle increases the potential for local reaction and chronic injection site nodules.
To locate the Vastus Lateralis site:
- Have the infant on their back, with the napkin undone.
- Gently adduct the flexed leg – locate the trochanter as the upper marker and the lateral femoral condyle as the lower marker.
- Section into thirds and run an imaginary line from the centre of the lower marker to the centre of the upper marker. (Look for the dimple along the lower portion of the fascia lata)
- The injection site is just above the junction of the upper and middle thirds i.e. the vaccine must be deposited no lower than the junction of the upper and middle thirds.
Immobilize the limb as above either by controlling the infant’s knee in the palm or the v-shape made when the vaccinator’s index finger and thumb are splayed.
For IM injection the needle should be inserted smoothly, at a 90-degree angle to the long axis of the leg and at least 1.5cm, i.e. one finger width above the junction of the upper and middle thirds.
If right handed, the vaccinator should consider giving the composite injection e.g. those containing the pertussis into the left thigh and vice versa – if left handed, administer the composite vaccine in the right thigh.
If the child is sitting sideways, the child’s right arm should be placed behind its parent’s back. The parent’s left arm is placed over the child’s left arm and chest ant their right arm should lie across the child’s legs and tuck under the child’s knee. If the child is in the straddle position, both the child’s arms should be behind their parent’s back and the parent then wraps his/her arms around the child’s body.
To administer two intramuscular injections in the same vastus lateralis muscle:
- When two intramuscular injections are to be given in the same vastus lateralis, the vaccinator’s injection technique needs to be very precise.
- Locate the correct anatomical landmarks as if administering one injection.
- Using a 90 degree angle, the first injection/needle insertion should be slightly above the junction of the upper and middle third as described.
- Ensuring that the second injection is at a 90-degree angle, needle insertion for the second injection should be 1-2cm distal of the junction.
- Injection sites should be separated by at least 2 cm, so that local reactions will not overlap.
- When giving two vaccinations in one limb both needle angles need to be the same, i.e. parallel. This will ensure vaccines do not mix within the muscle tissue.
Giving vaccines simultaneously has been found to be safe and effective. Providers tend to be more reluctant than parents to give several vaccinations at one visit.
The deltoid muscle is recommended and safest site for intramuscular injections in older children, adolescents and adults.
The entire deltoid muscle must be exposed otherwise the vaccinator will expose only the lower portion of the deltoid. The radial nerve is very superficial in the middle third of the upper arm, especially in children. An injection at the junction of the middle and upper thirds of the lateral aspect of the arm may damage the nerve.
To locate the deltoid site:
- Make sure the whole shoulder is exposed, e.g. by removing the arm from the garment sleeve.
- Find the acromion process as the upper marker. Find the deltoid tuberosity (in line with the axilla) as the lower marker.
- Draw an imaginary triangle pointing downward from the acromion.
- The injection site is in the centre of the triangle or the point halfway between the markers (it will be from one to four finger widths from the acromion, depending on the size of the arm).
Administering the vaccine:
The volume injected into the deltoid should not exceed 0.5ml in children and 1.0ml in adults.
Vaccinators need to be aware of the superficiality of the radial nerve and small deltoid muscle bulk if using the deltoid site for young children, i.e. over 15 months and up to 5 years of age. The vastus lateralis remains an option and it may be preferable to use this site for very small children. Consideration may be given to the vastus lateralis as an alternative site for adults, providing it is not contraindicated by the manufacturer’s information sheet.
Ø Subcutaneous Injection
A subcutaneous injection should be given into healthy tissue, which is away from bony prominences and free of large blood vessels or nerves. Subcutaneous tissue is found all over the body, but the most commonly used site is the upper arm, based on its accessibility and proven good vaccine uptake.
The principles for locating the deltoid site for a subcutaneous injection are the same as for an intramuscular injection, however needle length is more critical than angle of insertion for subcutaneous injections. While an insertion angle of 45 degrees is recommended, the needle should never be longer than 16mm or inadvertent intramuscular administration may result.
Factors that contribute to optimal intramuscular vaccine delivery
The following steps or measures will help reduce the incidence of local reactions:
1. Correctly stored vaccines
2. Relaxed muscle
3. Correct route
4. Correct needle length (careful use of a longer needle will cause less damage than a short needle)
5. Changing and not priming the new needle.
6. Needles should be routinely changed after drawing up because:
7. Most inactivated vaccines contain adjuvant and some contain thiomersal, both of which are very irritating to tissue.
8. A needle that has passed through a rubber stopper may be blunted and could possibly increase tissue trauma. In addition, minute rubber fragments may be caught in the drawing up needle and be injected into the muscle, contributing to local reactions.
9. Controlled injection rate. Use of a 1ml (e.g. tuberculin) syringe allows for greater control of the rate of plunger depression. The plunger on a 1ml syringe has less resistance than a 2 – 3ml syringe and therefore requires less force to depress it. Forceful depression of the plunger can cause vaccine to backtrack along the needle shaft to the skin surface. If a drop of vaccine is frequently seen at the skin surface following intramuscular injections, the vaccinator may be / is injecting too forcibly.
If using alcohol swabs, allow drying, otherwise alcohol can be tracked in with the needle.
10. Vaccines should not be mixed in the same syringe, unless the prescribing information sheet specifically states it is permitted.