TY - JOUR
T1 - Association between blood pressure, ultrafiltration, and hemodialysis graft thrombosis
T2 - A multivariable logistic regression analysis
AU - Paulson, William D.
AU - Ram, Sunanda J.
AU - Faiyaz, Rashid
AU - Caldito, Gloria C.
AU - Atray, Naveen K.
N1 - Funding Information:
Supported in part by a grant from Dialysis Clinic, Inc.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2002/10/1
Y1 - 2002/10/1
N2 - Although a low blood flow (Qa) is the most important cause of graft thrombosis, several studies have shown that Qa measurements do not accurately predict thrombosis. This suggests that additional variables may influence thrombosis. Identification of such variables may be essential to designing surveillance protocols that accurately predict thrombosis. In this nested case-control study, we prospectively followed 105 patients for up to 2.5 years in order to test the association of a number of variables with thrombosis. These included Qa (monthly by ultrasound dilution), percentage stenosis (quarterly by duplex ultrasound), mean arterial pressure (MAP), percentage ultrafiltration (%UF) during dialysis (%UF = 100[liters]/[kilogram of weight]), and other variables that defined patient and graft characteristics. Patients were divided into patent (n = 53) and thrombosed groups (n = 52), and MAP and %UF from seven consecutive dialysis sessions were analyzed. In the thrombosed group, the last session was the final session before thrombosis. A multivariable logistic regression model showed that Qa, MAP (the predialysis average of seven sessions), and %UF (from the last session) were independently associated with thrombosis, whereas all other variables were not. The model yielded the following odds ratios for thrombosis: for a single Qa value (reduction of 1,000 mL/min), 12.0 (P < 0.01); for %UF (increase of 4%), 5.3 (P < 0.01); for MAP (reduction of 30 mm Hg), 4.1 (P = 0.02); and for percentage decrease in Qa. (≥ 20% versus <20%), 2.4 (P = 0.12). We conclude that in addition to Qa, both %UF at the last session before thrombosis and average predialysis MAP from seven sessions are independently associated with thrombosis. These results help explain why Qa alone does not accurately predict thrombosis. A prospective study is needed to determine whether %UF at each session and a moving average MAP from seven sessions improve the prediction of thrombosis. However, it should be recognized that a large %UF is a preterminal event that likely provides too short a warning for intervention before thrombosis.
AB - Although a low blood flow (Qa) is the most important cause of graft thrombosis, several studies have shown that Qa measurements do not accurately predict thrombosis. This suggests that additional variables may influence thrombosis. Identification of such variables may be essential to designing surveillance protocols that accurately predict thrombosis. In this nested case-control study, we prospectively followed 105 patients for up to 2.5 years in order to test the association of a number of variables with thrombosis. These included Qa (monthly by ultrasound dilution), percentage stenosis (quarterly by duplex ultrasound), mean arterial pressure (MAP), percentage ultrafiltration (%UF) during dialysis (%UF = 100[liters]/[kilogram of weight]), and other variables that defined patient and graft characteristics. Patients were divided into patent (n = 53) and thrombosed groups (n = 52), and MAP and %UF from seven consecutive dialysis sessions were analyzed. In the thrombosed group, the last session was the final session before thrombosis. A multivariable logistic regression model showed that Qa, MAP (the predialysis average of seven sessions), and %UF (from the last session) were independently associated with thrombosis, whereas all other variables were not. The model yielded the following odds ratios for thrombosis: for a single Qa value (reduction of 1,000 mL/min), 12.0 (P < 0.01); for %UF (increase of 4%), 5.3 (P < 0.01); for MAP (reduction of 30 mm Hg), 4.1 (P = 0.02); and for percentage decrease in Qa. (≥ 20% versus <20%), 2.4 (P = 0.12). We conclude that in addition to Qa, both %UF at the last session before thrombosis and average predialysis MAP from seven sessions are independently associated with thrombosis. These results help explain why Qa alone does not accurately predict thrombosis. A prospective study is needed to determine whether %UF at each session and a moving average MAP from seven sessions improve the prediction of thrombosis. However, it should be recognized that a large %UF is a preterminal event that likely provides too short a warning for intervention before thrombosis.
KW - Arterial blood pressure
KW - Blood vessel prosthesis
KW - Graft blood flow
KW - Hemodialysis (HD)
KW - Stenosis
KW - Thrombosis
KW - Vascular graft occlusion
KW - Vascular patency
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U2 - 10.1053/ajkd.2002.35688
DO - 10.1053/ajkd.2002.35688
M3 - Article
C2 - 12324912
AN - SCOPUS:0036789680
SN - 0272-6386
VL - 40
SP - 769
EP - 776
JO - American Journal of Kidney Diseases
JF - American Journal of Kidney Diseases
IS - 4
ER -