P1128INTERMITTENT SALINE FLUSH VS CONTINUOUS SALINE INFUSION IN HEPARIN FREE DIALYSIS, A COMPARATIVE ANALYSIS
Authors: Sengupta Pratim , Biswas Sumanta , Sasmal Tarpan 
Published: June 2020

Abstract

Background and Aims
Proper anticoagulation during dialysis for the patients with bleeding risk or contraindication for heparin is a challenge. Regional anticoagulation with heparin and protamine or citrate and calcium though accepted has well known complications and has logistic and monitoring problem. Intermittent saline flush is another well accepted techniques. But it is labour intensive and often leads to fiber loss or coagulation of the dialyser. Keeping these in mind we hypothesised continuous prepump saline infusion may be another alternative technique in these situations. In this study We compared the outcome between intermittent saline flush versus continuous saline infusion while dialysing patients without heparine.

Method
Patients &gt;18 year of age, on mHD @3/wk atleast for 3 months, having mature Avfistula and Hb between 8.5-11.5gm/dl with standard EPO and decided for heparin free dialysis were included for the study. Exclusion criteria were Intradialytic weight gain more than 3kg receiving any blood component transfusion or albumin,parenteral nutritional product infusion, any need for UF /Na/HCO3 profiling. Patients on antiplatelet drug or P-time prolonged &gt; 6sec, APTT &gt; 2 times normal, and platelet count less than 80,000 were also excluded. After inclusion, for each patient 8 session were studied systematically as per the preset protocol. Session 1,3,5,7 was subjected to intermittent saline flush(ISF) where as session 2,4,6,8 were subjected to continuous saline infusion(CSIF). The blood flow during dialysis was kept in the range of 250ml/min to 300ml/min and dialysate flow was kept fixed at 500ml/min. and UF goal was kept between 2.5 to 3.5lit and treatment duration was fixed at 4hrs.In ISF, every 15min 80ml (=priming volume of the dialyser, F6, Polysulphone, Fresenius)0.9%NS was flushed in the dialyser clamping the arterial line where as in CSIF 0.9%NS bottle is connected to the prepump arterial line and saline is infused through saline infusion pump @320ml/hr. The each dialysis session outcome were recorded and analysed. Potential clotting in the bubble trap was visually observed in each hour and graded on a 4 point scale. 1=normal, 2= fibrinous ring,3=clot formation and 4= coagulated system. In either group the total saline infusion volume added in the net UF goal. The dialyser was inspected visually at the end of each session 1= normal,2= a few blood stripes affecting less than 10% of the surface area,3= many blood stripes more than 10% of surface area, 4= coagulated dialyser. URR(as per KDOQI guideline) and kt/v(by diascan software of Gambro AK96 machine) was calculated in each session. Data were analysed with spss v23.

Results
Total 8 patients(5men 3 women) were included for the study. After exclusion total 54 session of dialysis were finally analysed. The incidence of the of blood clot in the whole dialysis system leading to stopping of dialysis was 3 in ISF and 1 in CSIF (p=0.001).The multiple linear regression analysis with repeated measurememt for the time and UF rate adjusted clot incidence of different grade in bubble trap was significantly low in the CSIF group than the ISF group.(p=0.0001). When adjusted for total body water,net UF,PreHD Urea, blood flow the difference in URR and Kt/v both the group was not significantly different (p=0.8). Among the two group the operational comfort for nurses were significantly better(p=0.3) in the CSIF group than the ISF group.

Conclusion
While considering heparine free dialysis Continuous saline infusion @320ml/hr is easy less labourintensive method than intermittent saline flush technique with significantly less clotting incidence and without any adverse effect on the dialyser clearance.