Risk Factors Of Bruising With Subcutaneous Low Molecular Weight Heparin In Patients With Acute Coronary Syndrome

ObjectiveThis paper was to investigate the effects of different inject duration and pressing time on the bruising and pain caused by low molecular weight heparin in acute coronary syndrome patients,and to explore the risk factors for bruising.Then we can provide a reference for effective precaution.MethodsThe first portion: This study enrolled 90 adult patients who admitted to coronary care unit from October 2014 to June 2015.It was a self-controlled study that was conducted on patients with ACS receiving subcutaneous injection of low molecular weight heparin with different injection durations and pressing time.Every patient was received 4 injections in 4 ways.Injected for 10 s and waiting for 10 s before withdrawal(method A),Injected for 10 s and waiting for 10 s before withdrawal,then 5 minutes pressing time(method B),Injected for 30s(method C),Injected for 30 s then 5 minutes pressing time after withdrawal(method D).The injection areas were measured for the presence of bruising at 48 h after injection,The incidence and extent of pain were measured immediately after each injection.The second portion: The sample of this part was similar to the first part.During the first part,we also collected their clinical data,including age,gender,BMI,abdominal skinfold,diabetes history,using insulin,APTT,INR and platelet number.According to the results of the first portion,we chose method A and method B,and enrolled 80patients(160 injections)at last.Patients were divided into bruising group and control group in160 injections.Univariate analysis and multivariate Logistic regression analysis were conducted to compare the indicators mentioned above between the two groups to find out the risk factors.ResultsThe first portion: The incidence and extent of subcutaneous hemorrhage were significantly lower or smaller in group A and group C compared with group B and group D.The extent of pain was lower in group A and group C compared with group B and group D(P<0.05).The second portion: Bruising group had 94 injections,and control group had 66 injections.Age,gender,diabetes history,using insulin,APTT,INR and platelet number were not significantly different between the two groups(P>0.05);BMI?25,abdominal skinfold and pressing were significantly different between the two groups(P<0.05).The multivariate Logistic regression analysis showed that pressing((heavy strength,long time)after injection and abdominal skinfold <15.0mm were risk factors(P<0.05).ConclusionsIt is suggested that injected for 30 s or 10 s but waiting for 10 s before withdrawal and no heavy strength press can reduce the incidence of bruising and pain associated with subcutaneous low molecular weight heparin in ACS patients.But administering a solution of 0.4~0.6m L over more than 30 seconds is difficult,so we recommend the method inject10 s but waiting 10 s before withdrawal in clinical nursing.Patients with low BMI or thin abdominal skinfold seem to be prone to bruising.It also need clinical nurses to make further specification and research.