Q. Is it true that applying pressure to an injection site before giving an intramuscular injection reduces pain and, if so, why?
A. A patient’s perception of pain associated with intramuscular injection depends on a number of factors. These are listed in Box 1.
Women consistently report pain more than men, and the underlying medical condition and the patient’s previous experiences may also affect their perception of pain (Schechter et al, 2007).
The gate theory of pain control offers some understanding as to why digital pressure should reduce pain, as the combination of painful stimulus, perceived pain and emotion influence the patient experience.
Evidence for using digital pressure
Research studies have reported the positive effects of using digital pressure to reduce the perception of pain before administering an intramuscular injection (Alavi, 2007; Chung et al, 2002; Barnhill et al, 1996).
Barnhill et al (1996) used a visual analogue scale to measure the intensity of pain following the application of manual pressure to the injection site for 10 seconds before the procedure. More than one-third – 37% – of people included in the study reported less pain.
Chung et al (2002) studied 74 university students who were randomly allocated to receive a standard intramuscular injection, or 10 seconds of manual pressure before the procedure. The pain intensity verbal rating scale was used to measure pain. The researchers found that patients in the group that had received manual pressure reported less pain. The mean manual pressure applied was 190.82mmHg.
Box 1.Factors affecting pain associated with IMI
- The drug and volume injected
- Technique used
- Patient anxiety
- Patient position
- Speed of delivery of the drug
- The injection site
- Size of the needle bore and length
It appears that application of manual pressure has an effect on some patients’ perception of pain associated with intramuscular injections but the evidence is not conclusive.
Nurses are taught to use skills to relax or distract patients during painful procedures to reduce pain associated with anxiety. It is possible that distraction techniques and the nurse’s attitude during the 10 seconds of manual pressure before administering an injection are likely to influence the patient’s perception of pain.
If the 10 seconds of manual pressure is adopted into routine procedures, nurses need to consider infection control issues – for example, should sterile gloves be worn so that pressure can be applied after skin preparation and immediately before the injection? If the skin is prepared using an alcohol swab, which takes 30 seconds to dry, any positive effects of manual pressure applied before skin cleansing is lost.
Application of pressure is difficult to measure in practice. Visualising pressure at 190.82 mmHg is difficult because skin blanching, which is a visual sign of pressure, occurs at 16–32 mmHg (Dougherty and Lister, 2008).
Electronic pressure devices have been tested but evidence of their effectiveness is inconclusive (Schechter et al, 2007).
Whichever technique is used, it is important that nurses remember that pain is whatever the patient says it is.
Incorporating manual pressure into procedures for intramuscular injection needs careful consideration and infection control specialists should be involved in reviewing practice.
It can be argued that, if manual pressure has the potential to offer pain relief, it should be incorporated into the procedure, even if this is effective only for some patients.
- Assess the patient to ensure a good injection technique and suitability for manual pressure.
- Use communication skills/distraction to reduce anxiety
- Wear sterile gloves to administer manual pressure
- 10 seconds of firm digital pressure is necessary
Author Bridget Malkin, MAEd, BSc, RNT, RN, is senior lecturer clinical skills, Birmingham City University
Alavi, N. (2007) Effectiveness of acupressure to reduce pain in intramuscular injections. Acute Pain; 9: 4, 201–205.
Barnhill, B.J. et al(1996) Using pressure to decrease the pain on intramuscular injections. Journal of Pain Management; 12: 1, 52–58.
Chung,R.N.et al (2002)An experimental study on the use of manual pressure to reduce pain in intramuscular injections. Journal of Clinical Nursing; 11: 4, 457–461.
Dougherty, L., Lister, S. (2008) Royal Marsden Hospital Manual of Clinical Nursing Procedures. Chichester: Wiley-Blackwell.
Schechter, N. et al (2007) Pain reduction during pediatric immunizations: evidence-based review and recommendations. Pediatrics; 119: 5, 1184-1198.