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Background and Objective: The prevention of clot formation during hemodialysis improves the effectiveness of treatment by maintaining patency in the dialyzer. This study was done to evaluate the effect of intermittent bolus of normal saline on the quality of clot formation in venous chamber and dialyzer.
Methods: In this clinical trial study, 51 eligible patients were divided into intervention (n=26) and control (n=25) groups. Patients in the control group received routine care and the intervention group received 100ml of normal saline, each hour, as an intermittent bolus, during 4 hours of dialysis beside the routine care. After three consecutive hemodialysis sessions (first round), all patients received routine care to clear the intervention effect (washout period). Then, patients crossed over from intervention group to control and vice versa. At the end of each session, the quality of clot formation in intravenous chamber and dialyzer was recorded and analyzed.
Results: The venous chamber of dialysis circuit in 74% of patient in intervention group no clot was formed, whereas in 58% of patient in control group it contained fibrous ring (P<0.05). After intervention, dialyzer of 68% of patients in intervention group, were free of clot, whereas in control group only 16% of dialyzers were free of clots (P<0.05).
Conclusion: Using intermittent bolus of normal saline during hemodialysis can reduce the risk of clot formation in venous chamber and dialyzer.