Evento adverso, dor e imunogenicidade na administração de vacina por via intramuscular no ventro-glúteo sem aspiração antes da injeção: um ensaio clínico randomizado

Abstract

Introduction: Aspiration prior intramuscular injection (IM) is a long-standing practice, but it has only been scientifically studied in the last two decades, because there was no scientific evidence to justify its use, being adopted by nursing as a precaution to check if any blood vessel was reached. However, the sites commonly used for IM vaccination (vastus lateralis, deltoid and ventro-gluteal) do not have large caliber vessels. In addition, non-aspiration can reduce the pain in the procedure for making it faster. Thus, this study seeks to answer the following guiding question: the technique of non-aspiration prior to administration of vaccine intramuscularly is safe compared to the standard technique with aspiration? Objective: To evaluate the pain of the injection, the occurrence of adverse events and the immunogenicity after vaccination against Hepatitis A via IM in the ventro-gluteal region (VG) without aspiration to verify venous return. Material and method: This is a double-blind randomized controlled trial, performed with people aged 18 to 59 years using the Hepatitis A vaccine IM inactivated in the ventro-gluteal region, with a sample of 79 participants in the experimental group (EG) submitted to slow injection without aspiration and 76 participants in the control group (CG) at slow injection with aspiration. Individuals were allocated to groups through block randomization. The numerical scale of pain intensity was applied, it was measured the pulse per minute and peripheral oxygen saturation (SpO2) during vaccination, daily assessment of participants up to 72 hours after vaccination and serological analysis of the antibody titers against Hepatitis A (anti-HAV IgG) before and after vaccination. The data were tabulated in the Microsoft Office Excel Program and analyzed using the Statistical Package for Social Sciences (SPSS) software version 21.0. Descriptive and inferential statistical analysis was realized, considering statistical significance when p > 0.05 and 95% confidence interval. The study was approved by the Research Ethics Committee through consubstantiated opinion under number 3.315.929. Results: 155 people participated in the study, with a mean age of 38.28 years (sd ± 10.46), most of them men (68.4%, n = 106) and belonging to the brown race (62%, n = 97). The average of the pain scale was 1.83 points (sd ± 2.39) in the total population, female participants (p = 0.007) and older (p = 0.024) had lower pain intensity. The experimental group had a lower mean pain than the control group, but there was no statistical significance (p = 0.059). The occurrence of local and systemic adverse events was homogeneous among the groups submitted to the techniques with or without aspiration in the three days after vaccination (p > 0.05). Most participants (80.65%) had immunity prior to the Hepatitis A virus (≥ 10 mUI/mL), with an average anti-HAV IgG of 108.33 mUI/mL (sd ± 58.84). After vaccination, the mean antibody titers increased significantly (p = 0.000), with an average of 124.30 mUI/mL (sd ± 53.83), there were no significant differences between experimental and control group (p> 0.05). The variables gender, race, pre-existing disease and use of medication did not influence adverse events and the immunogenicity of the vaccine. Conclusion: The technique of IM vaccination without aspiration before injection is safe with regard to adverse events and immunogenicity in the administration of the Hepatitis A vaccine (inactivated) in the VG region compared to the conventional technique with aspiration, as well as presenting similar levels of pain during the procedure, classified as mild.