Near miss intra-arterial injection via a dual transducer pressure monitoring set

Abstract

We write regarding a potential hazard of using a dual transducer pressure monitoring set for arterial and central venous catheters. A 20-G right radial arterial catheter (Becton, Dickinson and Company Critical Care Systems Pte Ltd., Franklin Lakes, NJ, USA) and a right internal jugular quad-lumen central venous catheter (Arrow-Howes, Uxbridge, UK) were connected to a dual transducer pressure monitoring set (Edwards Lifesciences Ltd., Irvine, CA, USA), attached to a common 500-ml flushing bag of 0.9% sodium chloride held at a pressure of 300 mmHg. We subsequently noted that a milky substance was being infused down the arterial limb of the transducer set and was approximately 30 cm from reaching the radial artery. Closer inspection revealed propofol and alfentanil infusion pumps were connected via a ‘Y’ connector to the integral three-way stopcock present on the venous limb of the pressure monitoring set, downstream to the flushing device. This three-way stopcock was open, with all three connections communicating. The propofol, presumably with the alfentanil, had flowed in a retrograde direction up the venous limb of the transducer set into the common flushing bag, from where they were flushed down the arterial limb towards the arterial catheter. Inspection of the transducer set revealed no fault and the flushing fluid was maintained at a pressure 300 mmHg. However, there had been intermittent problems flushing several of the central line lumens during the preceding 24 h. We postulate that at some point, the resistance of the central line lumen must have increased through blocking or kinking or perhaps the three-way stopcock may have been temporarily closed to the patient, allowing retrograde flow of the propofol and alfentanil up the venous limb of the transducer set. A PubMed search found a similar incident reported in the correspondence section of Anaesthesia involving an intra-arterial injection of intravenous contrast agent through a dual transducer pressure monitoring set [1]. We wonder if intra-arterial injection of drugs via dual transducer pressure monitoring sets may occur more frequently than is reported. We reviewed our local practice following this incident. We have decided to eliminate the risk by using separate single transducer monitoring sets for arterial and central venous catheters. The use of dual transducer pressure monitoring sets requires vigilance and care when using the injection port of the venous limb for drug delivery. No external funding and no competing interests declared.