Nursing staff at our institution have reported frequent, large hematomas at subcutaneous injection sites when administering enoxaparin. Reports from the literature and the manufacturer suggest hematomas develop at subcutaneous injection sites in 5.1 to 19.3% of patients. Use of a smaller needle size has been anecdotally reported to limit injection site hematomas when administering enoxaparin.
To determine if using a 30-gauge, 5/16″ insulin syringe versus a 26-gauge, 3/8″ tuberculin syringe would significantly reduce the size of injection site hematomas and/or cause less pain on injection when patients were treated with enoxaparin (1mg/kg q12h) for unstable angina or non-Q-wave myocardial infarction.
The emergency department, intensive care unit, and cardiology ward of a 675-bed community hospital in Canada.
A prospective, randomized study. Patients presenting to the emergency department with unstable angina or non-Q-wave myocardial infarction and prescribed enoxaparin were randomized to receive subcutaneous injections by one of the two study needles. Every twelve hours, prior to the next administered dose, nurses inspected designated injection sites and measured any hematomas present. After the dose, nurses asked the patient to rate the pain on injection.
Main Outcome Measures
Size of largest hematoma formed, measured at the widest diameter in centimeters. Pain associated with injection, using a 10-point numerical pain scale.
There was no significant difference in the median size of the largest hematoma (3.5 cm with the insulin syringe group versus 2.3 cm with the tuberculin syringe group, p=0.68) and no significant difference in the average pain score (0.31 units with the insulin syringe group versus 0.53 units with the tuberculin syringe group, p=0.10).
Use of a 30-gauge, 5/16″ insulin syringe versus a 26-gauge, 3/8″ tuberculin syringe does not significantly reduce hematoma size nor does it significantly reduce pain on injection.