Effect of Enoxaparin Injection Duration on its Complications in Myocardial Infarction Patients

Enoxaparin is a subcutaneous anticoagulant that has some side effects, including bruising and pain at the injection site. The incidence of the side effects can prevent the patient from continuing the treatment. Since one of the most important duties of nurses is the safe and low-complication injection of drugs, such as enoxaparin, this study aimed to examine the effect of the duration of enoxaparin subcutaneous injection on the intensity of pain and the incidence of bruising, as well as the size of it, in injection site among patients with myocardial infarction.

This semi-experimental research was conducted on 56 patients treated with enoxaparin and hospitalized in the cardiac care unit of Shahid Madani Medical Training Center in Tabriz, Iran, in 2021. After an initial convenience sampling, the samples were divided into 2 groups by random allocation. Enoxaparin injections were done in all patients by the researcher. The injection was done within 10 and 30 s for the control and experimental groups, respectively. The intensity of pain was measured by a numerical pain rating scale immediately after each injection, and the incidence and size of bruising were assessed with a transparent ruler in square millimeters 48 hours after each injection. Data analysis was conducted in SPSS V. 22 at a significance level of 0.05.

In the present study, the mean scores of pain intensity (P=0.0001), the incidence of bruising (P=0.029), and the size of the injection site bruise (P=0.044) were significantly lower in enoxaparin injection within 30 s than 10 s.

Due to the significant reduction in pain intensity and the incidence and size of bruises after increasing the duration of enoxaparin subcutaneous injection and, therefore, the improvement of the quality of care and reduction of the unpleasant and stressful experiences of patients, it is suggested to increase the duration of injection to 30 s.