Suzanne Robertson-Malt, Greg N Malt, Vincent Farquhar, William Greer

For most patients who require intensive care, the success of clinical decision making and interventions is dependent on the accuracy of different physiological variables measured or obtained from samples using an arterial catheter. Maintaining the patency of these catheters is therefore essential for obtaining accurate measures, minimizing patient discomfort and reducing expenses incurred when an occluded catheter requires replacement. Uncertainty exists amongst clinicians as to best practice surrounding the contents of the arterial catheter flush solution (heparin or saline). The use of heparin is more expensive and is accompanied by significant risks such as haemorrhage, hypersensitivity and heparin-induced thrombocytopenia (HIT).