2 International Journal of Nephrology Figure 1: Right upper arm AV ﬁstula aneurysm of the patient. Size is approximately 6 × 3 cm. drove himself home. About 30 minutes after his dialysis treatment ended, he called a friend and complained of bleeding from his AVF. The friend arrived half an hour later and called 911. The patient was coherent and conscious but complaining of generalized weakness, fatigue, and short- ness of breath. Emergency medical services responded and applied a pressure dressing to his AVF. Upon arrival in the ER, his blood pressure was 117/98 mmHg, pulse 79, and regular, respiratory rate 18, temperature 98.6 F, SpO2 92% on room air. He was pale and there was an area of aneurysmal dilatation of the right AVF with a pinpoint area of bleeding which had largely stopped with pressure. Patient’s AVF is shown in Figure 1. A short arm cast was on the right wrist (wrist fracture had occurred three weeks earlier). There were no obvious signs and symptoms of infection of the AVF and no recent antibiotic use. Initial labs were remarkable for Hgb 6.7 gm/dL and Hct of 21.8%. Of note, his hemoglobin the prior month was 13.2 gm/dL. His PTT, INR, and platelets were normal. The patient was transfused 5 units of packed red blood cells with appropriate response in hemoglobin. Blood cultures remained negative. A tunneled catheter was placed for hemodialysis access. A new left arm basilic vein transposition AVF was created along with ligation of the right brachiocephalic AVF. Three months later, the right brachiocephalic ﬁstula was removed by vascular surgery; intraoperatively a pseudoaneurysm and thrombosis of the AV ﬁsula were observed. His hemoglobin six months after discharge is stable at 12.5 gm/dL. 3. Discussion The Centers for Medicare and Medicaid Services Interpretive Guidance Update requires every dialysis facility to have an ongoing program for vascular access monitoring and surveillance for early detection of failure and to allow timely referral of patients for intervention. Physical examination can be used as a monitoring tool to exclude low ﬂows associated with impending vascular access failures. There are 3 components to the access examination: inspection (look), Table 1: Causes of blood loss through AV ﬁstula. Causes of blood loss through AV ﬁstula (1) Aneurysm formation (2) Stenosis and subsequent rupture (3) Infection (4) Trauma (5) Use of anticoagulants and antiplatelets (6) Suicide palpation (touch), and auscultation (listen). Simple inspec- tion can reveal the presence of aneurysms. A ﬁstula that does not at least partially collapse with arm elevation is likely to have an outﬂow stenosis. Strictures can be palpated and the intensity and character of the bruits can suggest the location of stenosis. Downstream stenosis also produces an overall dilation of the vein, giving it “aneurysmal” proportions. Observance of changes in adequacy or in pressures measured during dialysis, diﬃculties in cannulation, or in achieving hemostasis may also be used as monitoring tools [1–4]. Surveillance strategies include device-based methods such as access ﬂow measurements, direct or derived static venous pressure ratios, and duplex ultrasound, and so forth. However, the proper role of surveillance awaits the results of further research. The best available evidence indicates that ﬁstula surveillance does not prolong ﬁstula life and there is limited evidence that surveillance may reduce ﬁstula thrombosis [4]. Serial monitoring of aneurysms may give the opportunity to potentially prevent rupture by timely intervention. Evidence of periodic monitoring and surveillance of the vascular access should be documented on the dialysis treatment record, progress notes, or on a separate log. A member of the facility staﬀ must review the vascular access monitoring/surveillance documentation to identify adverse trends and take action if indicated. Our patient probably would have beneﬁted from early vascular surgical intervention before an episode of life threat- ening hemorrhage. He was on both aspirin and clopidogrel although the current evidence suggests that the combined use of aspirin and clopidogrel does not oﬀer greater beneﬁt for stroke prevention than either agent alone but does substantially increase the risk of bleeding complications [5]. Thus, it is likely that the antiplatelet agents contributed to his bleeding and stopping the [6] dual antiplatelet therapy should have been considered when aneurysmal dilation of the ﬁstula was initially noticed. The most common sources of acute access blood loss in hemodialysis patients are shown in Table 1. These will be brieﬂy reviewed. 3.1. Aneurysms. Aneurysms usually occur in long-lasting arteriovenous ﬁstulas and form in areas of repeated needle puncture sites [7]. Repeated needle punctures of the arte- rialized veins over time result in destruction of the venous wall and replacement by scar tissue causing loss of elasticity. Subsequently, thinning of the vessel wall increases the risk