Effectiveness of helfer skin tap technique on pain among infants undergoing intramuscular vaccination – A randomized controlled trial

Introduction

Pain is a frequent concern among parents of infants getting multiple injectable vaccines in a single visit. Long-term, unpleasant, and unfavourable experiences during vaccination might lead to its avoidance in the future. It poses health risks to individuals and the general population.¹ Early pain exposure has lasting, significant consequences on the developing neurological system.² When pain is not addressed at the moment of vaccination, it might progress to vaccine hesitancy. It will have a negative impact on future health-seeking behaviour and healthcare decisions.³ The WHO’s Strategies Advisory Group of Experts on Immunisation (SAGE) has emphasized the importance of preventing and mitigating pain and distress during vaccination to combat vaccine hesitancy.⁴

In 1998, Joanne Kieffer Helfer, RN (USA) developed a technique to alleviate pain through intramuscular injections by tapping the skin over the injection site. The pain theory is the foundation for this concept. This concept also employs Roger Melzack and Past wall’s (1965) gate control theory of pain. Here, this technique involves applying mechanical stimulus to the skin. This changes the balance between the small-diameter fibers that transmit pain sensations to the brain and the large diameter fibers that do not transmit pain. The faster, small diameter pain conveying fibers are blocked by the large, non-pain fibers. There are two major points to consider. One is muscle relaxation, which reduces resistance to needle entrance physically. Another is a distraction, which is achieved by tapping the skin simultaneously during the insertion and removal of the needle.⁵

Infant vaccination pain management aims to reduce the level of iatrogenic pain associated with vaccination and vaccine hesitancy rate. In this context, nurses are responsible for employing the most effective pain management strategy. The “Helfer Skin Tap Technique” is a simple yet cost-effective non-pharmacological alternative that has emerged in recent years. The study aims to improve the evidence supporting the effectiveness of Helfer Skin Tap Technique in decreasing injection-related pain in infants and promote the use of evidence-based therapies.

The objectives of the study were to evaluate the effect of the Helfer skin tap technique on pain level among the infants undergoing intramuscular vaccination and to find out the association between pain level with selected demographic variables.

Methods

Protocol

Clinical trial was carried out after getting registered on Clinical Trial Registry – India (http://ctri.nic.in), on 16/04/2021 with CTRI registration number CTRI/2021/04/032860. Formal written permission was taken from HOD of the Pediatric department and In charge of Immunization department PBMH, KIMS, Bhubaneswar to conduct the study. The clinical trial was conducted from 01.05.2021 to 15.05.2021. The design of the study (CONSORT flowchart) is displayed in Figure 1.

Figure 1. Consort flowchart of the study.

This research obtained approval first from KIMS Medical Research Committee on Date: 14/12/2020 (No.: KIMS/R&D/52/PG/2020/13) and then approved by Institutional Ethics Committee, KIMS, Bhubaneswar on date: 09/02/2021 (Ref. No.: KIIT/KIMS/IEC/582/2021). This research adhered to the Declaration of Helsinki. All participant’s parents/guardians were provided informed consent documents outlining the study’s objectives by the researcher at the study site. Then data was collected by the researcher after taking written consent from them. The inclusion criteria for selecting as a sample were infants undergoing the Penta or Hexaxim vaccine at the immunization clinic, PBMH, KIMS, Bhubaneswar. A computer-generated random number list was used to select the sample from the population as per inclusion criteria and grouped it into experimental and control groups.

We placed infants on the firm surface of the bed in a supine position. Confirmation was done regarding the name of the vaccine (Penta or Hexaxim) and the frequency of vaccine (I^st/ II^nd/III^rd) administered to the infant. Post identification of the intramuscular vaccination site, i.e., the anterolateral thigh muscle, that area was disinfected with surgical spirit, and the syringe was uncapped in the dominant hand. Then a broad ‘V’ shape was formed with the thumb and index finger of the non-dominant hand, and rhythmic tapping was conducted with the palmar surface of the dominant hand, over the skin sixteen times (approximately 10 seconds) to relax the muscle. Again, tap the skin three times. The needle was concurrently placed into the muscle at a ninety-degree angle on the count of one. Tapping was continued, and with a count of three, the needle was removed. “Counting to three facilitated the investigator to synchronize the muscle tap with the insertion and removal of the needle,” so as to further relax the muscles. We video recorded the whole procedure. By using this video, we assessed the pain level during intramuscular vaccination by using the ‘Neonatal Infant Pain Scale (NIPS).’ We obtained baseline measures shortly before the injection procedure.

The primary outcome of the study was to assess the level of pain. To assess the pain score, we used Neonatal Infant Pain Scale (NIPS) as the tool. It is based on six items.⁷ Facial expression, arms, legs, and state of arousal are evaluated between 0 and 1 points while cry is evaluated as 0-1-2 points. So the total possible score is 0 to 7. A score of ‘0’ indicates no pain. Scores ‘1 to 3’ indicate discomfort, scores ‘4 to 6’ indicate pain, and scores ‘7’ indicate the worst pain on a level of the pain continuum.

We finalized 62 samples for analysis.¹⁰ Demographic variables were collected from their parents or guardians using interview techniques. In this study, demographic variables were age (weeks), current weight (kg), gender, name of vaccine, and frequency of vaccine. The method of data collection was questioning to collect demographic variables and observation to find out the effect of an intervention.

Results

A total of 62 participants completed the interventions, and data from these participants was analyzed for the study. The samples in the experimental group were not statistically different from the control group ( Table 1) concerning current weight (p= 0.577), gender (p= 0.204)), name of vaccine (p= 0.671). Statistical significance was seen among two groups concerning age (weeks), the only non-parametric data, and frequency of vaccine at a p-value of 0.005 and 0.010 respectively.

The presence of statistical significance between the experimental and control groups on the basis of age and frequency of vaccine indicates that groups were not different from each other and the absence of statistically significant difference on other variables indicates that groups were homogeneous based on those variables.

The mean pain score ( Table 2) of the control group with the standard injection technique was 6.55 (SD ± 1.028) which was higher than the mean pain score in the experimental group with Helfer skin tap technique of 5.52 (SD ± 1.411), with a mean difference of 1.032 and a p-value of 0.002, which was statistically significant.

On the level of pain continuum on the NIPS tool ( Table 3), though the majority of infants 20 (64.5%) in the experimental group experienced pain, only 9 (29%) infants experienced the worst pain, whereas in the control group, the majority of infants, 23 (74.2%) experienced the worst pain. The level of pain had statistical significance for both groups, i.e., experimental and control groups, with a p-value of 0.002.

On analysis of the ‘association between pain level and selected demographic variables’ ( Table 4), it was seen that there was no statistically significant association between any of the demographic variables and the level of pain experienced by infants during intramuscular vaccination. The variables were independent of the level of pain.

Discussion

In this study, level of pain evaluated during intramuscular vaccination applying Helfer skin tap technique was found to be significantly lower than the level of pain obtained with standard injection technique ( Table 2). The study outcome confirmed Helfer skin tap technique is an effective one in reducing pain intensity accompanying with injection. This result is in line with a study conducted in Ambala, Haryana with 100 infants showed a significant difference in the level of pain with and without Helfer skin tap technique.⁸

In this study, results also highlighted that with standard injection technique, more infants suffered higher intensity of pain as compared to to Helfer skin tap technique ( Table 3). “It is also consistent with another study where 86 % of the neonates in the experimental group had mild pain, only 14% perceived severe pain during IM injection by using Helfer skin tap technique and reverse was found by using conventional routine technique.”⁹

In this study, demographic variables like age, current weight, gender, name and frequency of vaccine did not have a significant relation to the level of pain during intramuscular vaccination ( Table 4). In contrast to this, a similar study shows that a significant association was found between gender and the pain level of infants during intramuscular vaccination in routine group.

There are a limited number of studies investigating the effects of age and gender on pain, fear and anxiety.⁷

Conclusion

Pain is a major concern for children, their families, as well as healthcare providers during vaccination. To deal with this fifth vital sign, it’s high time to implement evidence-based strategies for reducing vaccination pain among children. In light of the prevalence of pain during vaccination, the present study concluded that no method can completely remove the pain associated with it, but with the help of the Helfer skin tap technique, the pain associated with intramuscular vaccination is lessened. So, “Helfer skin tap technique” is indeed an effective one which is highly recommended to be implemented alone or along with other non-pharmacological complementary therapy in a clinical set-up during intramuscular vaccination.