Physical examination of dysfunctional arteriovenous fistulae by non-interventionalists: a skill worth teaching

Background. Physical examination (PE) of arteriovenous fistulae (AVF) has recently emerged as an important element in the detection of stenotic lesions. This study examines the accuracy of PE in the assessment of AVF dysfunction by non-interventionalists in comparison with angiography. Methods. A total of 177 consecutive patients who had AVF dysfunction and were referred to our centre by general nephrologists for angioplasty between November 2009 and July 2010 were included in this analysis. Eleven referring general nephrologists completed a form reporting the PE findings regarding their patients' AVFs. Before angiography examination was carried out, a trained nephrology resident performed a PE in all the cases. Angiography of the AVFs was then performed by an interventionalist. Cohen's kappa value was used as the measurement of the level of agreement beyond chance between the diagnosis made on PE and angiography. Results. There was a moderate agreement beyond chance between the general nephrologists' PE and angiography in the detection of AVF inflow stenosis (kappa = 0.49), outflow stenosis (kappa = 0.58) and thrombosis (kappa = 0.52). On the other hand, PE performed by the trained nephrology resident strongly agreed with angiography in the detection of AVF inflow stenosis (kappa = 0.84), outflow stenosis (kappa = 0.92) and thrombosis (kappa = 0.98). The agreement between PE and angiography in the detection of co-existing AVF inflow-outflow stenosis was poor for the general nephrologists and moderate for the trained nephrology resident (kappa = 0.14 versus kappa = 0.55, respectively). Conclusion. PE may provide an accurate means of diagnosis of AVF dysfunction. Theoretical and hands-on training in PE of dysfunctional AVFs should be provided for nephrologists in-training and for the dialysis staff.