Arterial Pump Discussion

Re-evaluation of Prepump Arterial Pressure to Avoid Inadequate Dialysis and Hemolysis: Importance of Prepump Arterial Pressure Monitoring in Hemodialysis Patients Eriko Shibata, *Kojiro Nagai, †Risa Takeuchi,[2015]

aim of this study was to clarify the importance of PreAP in the prediction of inadequate dialysis and hemolysis. Prepump arterial pressure (PreAP) is monitored to avoid generating excessive negative pressure. PreAP should not fall below −250 mm Hg because excessive negative PreAP can lead to a decrease in the delivery of blood flow, inadequate dialysis, and hemolysis. PreAP monitoring has also been shown to be useful in the avoidance of harmful negative pressure which could give rise to blood damage. Blood damage is one of the primary complications in hemodialysis (HD). Any damage to red blood cells can decrease the cellular life span and contribute to anemia. Several factors contribute to hemolysis, including shear stresses, blood/air interface, and blood attachment to foreign surfaces more cost-effective systems, including automatic priming and reinfusion systems using dialysate, Result PreAP is an important factor that affects both delivered blood flow and hemolysis. The threshold of PreAP that contributes to these problems was −150 mm Hg. PreAP monitoring methods, such as pulsating movement and a pressure pillow, were not effective in the detection of optimal PreAP PreAP is a critical factor in the delivery of actual blood flow. Blood flow also causes shear stress, which is one of the primary causes of hemolysis. Peripheral dialysis needles are expected to have the highest shear stresses within a dialysis circuit.

Arterial line pressure control enhanced extracorporeal blood flow prescription in hemodialysis patients Franklin G MoraBravo*†1, Alfonso Mariscal†1, Juan P Herrera–Felix†1, Salvador Magaña†1,[2008]

An extracorporeal is a medical procedure which is performed outside the body The extracorporeal circuit provides the necessary conduit for transporting blood from the patient's vascular system (via arteriovenous access) The pressure generated by the pump carries blood flow into the arterial segment of the dialysis circuit (arterial line) and is measured continuously, denominated dynamic arterial line pressure (DALP). DALP is a negative pressure that has been used to determine catheter dysfunction, which is identified when a dialysis blood flow of 300 mL/min is not being attained in a catheter previously able to deliver greater Qb than 350 mL/min and at a pre pump pressure of -250 mmHg3 The instrumentation and continuous measurement of the pressures in the arterial and venous lines allow us to know static and dynamic parameters of the internal pressure in the access site. Methods Patients

We enrolled 91 patients from our chronic hemodiafiltration (HDF) dialysis unit and in the renal transplant program from our institute, who received 3 HDF sessions per week (11.5 to 12 hrs/wk). Patients received anticoagulation with heparin sodium 2.000 units at the beginning of treatment and 1000 units per hour. The machines are equipped with a pre pump measuring system for dynamic arterial line pressure, a blood temperature monitor (BTM) Dynamic arterial line pressure is a negative pressure generated by the machine's peristaltic pump. The dynamic nomination must be, so that it translates the negative pressure of the pump in movement from arterial line to vascular access. This study describes extracorporeal blood low prescription based on DALP which permits to optimize Qb until limits near to 500 ml/min could be attained. In conclusion this investigation has shown that Qb prescription can be optimized by DALP. DALP of -200 mmHg is recommended for obtaining the best Qb. Staff adherence to DLAP treatment prescription could be reached up to 81.3% in catheters and 84.1% in AV fistulae

How to perform a haemodialysis using the arterial and venous lines of an extracorporeal life support Sylvain Rubin a,*, Anne Poncet a, Alain Wynckel b,[2009]

In the past few years, the extracorporeal life support (ECLS) is being used more frequently to assist adult patients presenting acute cardiac and pulmonary dysfunctions The femoral vein is less frequently chosen, due to the septic risk, and the potential risk of thrombosis in the neighbourhood of the ECLS cannulae. These conclusions lead us to imagine an ‘illogical’ but original and very simple solution to connect the haemodialysis on the venous and arterial lines of the ECLS. The inflow of the haemodialysis is connected to the arterial line, and the outflow is connected to the venous line using two 3-way taps (Luer Lock). Due to the constant low cardiac output before the ECLS implantation, the haemodialysis is frequently required at the time of the assistance initiation In summary, during a haemodialysis, the arterial blood is taken from the corresponding line and re-injected by the venous line, creating a shunt due to the recirculation of the haemodialysed blood in the ECLS. In practice, the haemodialysis needs a stable blood flow rate between 150 ml min_1 and 180 ml min_1 and filtration flow rates ranges from 30 ml min_1 to 40 ml min_1 to provide an adequate urea clearance. Therefore, it can be overlooked because of the performance of the actual ECLS (mean blood flow: 3.9 l min_1).

Surveillance and Monitoring of Dialysis Access Lalathaksha Kumbar, Jariatul Karim, and Anatole Besarab[2011]

Currently arteriovenous fistula (AVF) and arteriovenous graft (AVG) have been recognized as the permanent accesses for a dialysis patient with tunneled cuffed catheter (TCC) being the bridge to obtain a permanent access. A lasting and properly functioning access is crucial to provide adequate dialysis to improve the quality of life of maintenance hemodialysis patients and to reduce the huge access-related cost in this population

Does the extracorporeal blood flow affect survival of the arteriovenous vascular access?

However, Qb is restricted by vascular access (VA) quality and/or concerns that high Qb could damage the VA. Taking VA quality into consideration, one can investigate the relationshipbetween Qb and VA survival. We analyzed data from 1039 patients treated by hemodiafiltration over a 21-month period where access blood flow (Qa) measurements were also available at baseline.

Pedro PONCE,1 Daniele MARCELLI,2 Caecilia SCHOLZ,2[2015]

Vascular access (VA)-related complications are only second to cardiovascular problems as the primary cause for hospitalization in patients on chronic hemodialysis treatment. The study population comprised 1039 patients undergoing postdilution HDF in 19 Fresenius Medical Care’s NephroCare clinics in Portugal between April 2011 and January 2013. VA failure was defined as the first surgical intervention that resulted in the creation of a new VA. This study did not find a significant association between extracorporeal blood flow and survival of the VA for the 231 patients dialyzed with AVGs. In comparison, analysis of VA survival for 808 patients treated via a fistula revealed a significantly higher risk of VA failure for Qb less than around 310 mL/min and for Qb greater than around 400 mL/min compared with the reference Qb of 350– 357 mL/min.