1.1 Inclusion criteriaPatients were eligible to participate in this study if they aged 18years or older, are alert to be able to express pain, agreed to give informedconsent, and receiving SC injection of 40 mg enoxaparin with the volume of 0.4or 60 mg enoxaparin with the volume of 0.6 ml once per day. 1.1.
2 Exclusion criteriaPatient who had any of the followingcriteria was ineligible to participate: (1) discharge earlier than 72hrs, had (2)Any impairment in coagulation profiles such as thrombocytopenia, prothrombin time,platelets count, International Normalized Ratio, (3) Liver functiondisturbance, (4) Scar tissues or old hematoma at the site of injection, andsensory alteration.1.2 Instruments One questionnaire and two scales were used to collect thedata:1.2.1 Demographic and Medical History Data SheetThis sheet was designed by the researchers to collect the baseline characteristicsand medical history data of the participants such as; age, gender, maritalstatus, education, employment status and medical diagnosis. 1.2.2 Pain Numeric Rating Scale (PNRS) Pain NumericRating Scale (PNRS) has a single 11-point numeric scale in which respondentsselect a number from 0 (no pain) to 10 (severe pain) to reflect the intensityof their pain.
The scale has high test–retest reliability in both literate andilliterate patients (r = 0.96 & 0.95, respectively) 16. Therefore, PNRSwas used in this study to assess the pain intensity as perceived by theparticipant. The participants were requested to select the number that mostlyrepresents their pain intensity. 1.
2.3 Hematoma Formation and Size Assessment Scale (HFSAS)It wasfound that the hematoma peak after injection was at 48hrs and the beginning ofhealing at 72hrs after injection 17, thus hematoma in this study was observedat 48hrs and 72hrs after SCAI. A transparent ruler scale was used to measurethe total hematoma size with millimeter unit 4. 1.3 Pilot StudyOnce permission was granted to proceed with theproposed study, a pilot study was conducted before starting data collection on10 patients to assess its feasibility as well as the applicability of thetools. Participants who shared in the pilot study were excluded from the main studysample. The result of the pilot study confirmed that the study was feasible.
1.4 Procedure of datacollectionOnce official permissions were granted from the headsof the departments to proceed with the study, the researchers initiated datacollection. Patients meeting the inclusion criteria were approachedindividually, and assigned randomly into three equal groups, control group (G1),and study groups (G2 & G3) (35 patients for each).This study was conducted in three phases as the following:Assessmentphase: The researchersinterviewed the eligible participants and explained the study aim in order toobtain their informed consent and collect the demographic and medical baselinedata. At this phase, all patients who were willing to participate in the study wereassessed for deciding the site of SCAI. The injection site was selected takinginto consideration that it should be free from any scars or hematoma before theintervention.
Interventionphase: At this phase, the researchers were applyingthe cryotherapy through ice in plastic page for five minutes for the two studygroups (G2 immediately before injection, and G3 immediately after anticoagulantinjection). For controlling confounders that have been shown by previousstudies as factors for increasing pain sensation and hematoma formation 5-7,18,the two study and control groups received the same injection technique. Forinstance, the anticoagulant dose was slowly injected over a period of 30seconds using a syringe ready for injection,with insertion angle of 90 degree, with no aspiration before the injection, andby holding the skin of the injection site between the thumb and index finger, sincethese techniques can reduce pain intensity and hematoma formation 6-7. Afterinjection, a piece of cotton was placed on the injection site and was thenremoved without rubbing. Kenko sports chronometer was used to measure theduration of injection.
A circle was done around the injection site for allgroups in order to make sure it will not be selected again for the followinginjection, also to assess the occurrence and size of hematoma. Additionally,the nurses were informed not to inject the selected arm through the studyperiod. Moreover, the patients were instructed not toaffect the injection site (itch, touch, & massage).Evaluationphase: The researchersassessed the pain immediately after theneedle was withdrawn among the G1 and G2, while, among G3; pain was measured fiveminutes after applying the cryotherapy using the PNRS. The hematoma was assessedfor the three groups after 48hrs and 72hrs by the researchers using the HFSAS.
1.5 Ethical considerations An official approval and permissions from the director of thehospital and the heads of the departments were obtained. The study was conductedin accordance with the Helsinki Declaration.
All the participants gave an informed consent after theywere given full explanations about the study aim and benefits. It wasemphasized that participation in the study is voluntary. Confidentiality of patientwas assured through coding of all data. In addition, the participants wereinformed that they could refuse or withdraw from the study at any time without givingany reason. 1.
6 Data analysisThe Statistical Package for the Social Sciences (SPSS) version20 was used for data entry, tabulation and analysis. Descriptive statisticswere computed to summarize the patients’ demographic and medical data. Aone-way between groups analysis of variance (ANOVA) was conducted to explorethe impact of the intervention on perception of pain intensity and hematoma formation.If the output of the ANOVAtest was statistically significant, the Post hoc Tukey technique was usedto find which of the three groups was statistically different.
To compare the categorical variables, Chi-square was used and to findthe difference in hematoma formed across three groups, a non-parametric ANOVA(Kruskal-Wallis) test wasused. For a multiple regression analysis; nominal variables treated as ordinal(education: highly educated is “higher” than illiterate, employed is “higher”than unemployed) and age hold as ratio data. The statistical significance pointwas considered at p-value <0.05.