Several needle types can be used to draw up intravenous drugs. Compared with sharp-bevelled hypodermic needles, blunt fill needles are thought to reduce the risk of needlestick injury . The addition of a filter to a blunt fill needle reduces the risk of injecting glass vial fragments, but has not been shown to improve patient safety and incurs increased cost, implying that the use of blunt fill filter needles should be restricted to high-risk patients such as neonates and the critically ill , or injections to high-risk sites including the eye or subarachnoid space.
We found that 15/24 (63%) anaesthetists of varying grades at the Royal Oldham Hospital used both hypodermic and blunt filter needles when drawing up drugs for intravenous use. The choice of needle depended mainly on whether there was a rubber bung on the ampoule, whether the ampoule was glass and the volume of drug being drawn up. Only three anaesthetists stated that they used filter needles to reduce the potential risk of harm from particulate glass injection, but they were not aware of any published evidence supporting such risk reduction. Only three different anaesthetists were aware of the cost implications of their needle choice.
We noted a marked difference between the unit cost of 19-G and 21-G hypodermic needles (B Braun, Melsungen, Germany, £1.96 (€2.44, $3.12) and £1.57 (€1.95, $2.50) per box of 100, respectively) and 18-G blunt fill and 18-G blunt fill filtered needles (BD, Franklin Lakes USA, £6.70 (€8.34, $10.68)/100) and £32.68 (€40.68, $52.08)/100), respectively, at our hospital. We calculated that replacing all blunt fill filter needles (annual cost £13 595 (€16 920, $21 661)) with blunt fill non-filter needles (equivalent cost £2787 (€3469, $4443)) for intravenous drug administration would save £10 808 (€13 452, $17 226) annually, or £12 940 (€16 105, $20 621) if filter needles were replaced with hypodermic needles.
Due to the increased cost and lack of evidence for their use, we intend to restrict the use of blunt fill filter needles in our hospital to preparing drugs for central neuraxial blockade and ophthalmic anaesthesia, and for high-risk patients, at the anaesthetist's discretion. Repeated on a national scale, we suggest that this approach could earn significant savings for the National Health Service.