Acute hemodynamic response and uremic toxin removal in conventional and extended hemodialysis and hemodiafiltration: a randomized crossover study.
BACKGROUND
Intensive hemodialysis (HD) may have significant benefits. Recently, the role of extended hemodiafiltration (HDF) has gained interest. The aim of this study was to evaluate the acute effects of extended HD and HDF on hemodynamic response and solute removal.


METHODS
Randomized crossover trial.


METHODS
Stable patients with end-stage renal disease undergoing conventional HD.


METHODS
13 patients randomly completed a single study of 4-hour HD (HD4), 4-hour HDF (HDF4), 8-hour HD (HD8), and 8-hour HDF (HDF8), with a 2-week interval between study sessions. Between study sessions, patients received routine conventional HD treatments.


RESULTS
Acute hemodynamic effects and uremic toxin clearance.


METHODS
Blood pressure and heart rate, pulse wave analysis, cardiac output, and microvascular density by sublingual capillaroscopy, as well as relative blood volume and thermal variables, were measured. Clearance and removal of uremic toxins also were studied.


RESULTS
Long treatments showed more stability of peripheral systolic blood pressure (change during HD4, -21.7±15.6 mm Hg; during HDF4, -23.3±20.8 mm Hg; during HD8, -6.7±15.2 mm Hg [P=0.04 vs. HD4; P=0.08 vs. HDF4]; and during HDF8, -0.5±14.4 mm Hg [P=0.004 vs. HD4; P=0.008 vs. HDF4]). A similar observation was found for peripheral diastolic and central blood pressures. Cardiac output remained more stable in extended sessions (change during HD4, -1.4±1.5 L/min; during HDF4, -1.6±1.0 L/min; during HD8, -0.4±0.9 L/min [P=0.02 vs. HDF4]; and during HDF8, -0.5±0.8 L/min [P=0.06 vs. HD4; P=0.03 vs. HDF4), in line with the decreased relative blood volume slope in long dialysis. No differences in microvascular density were found. Energy transfer rates were comparable (HD4, 13.3±4.7 W; HDF4, 16.2±5.6 W; HD8, 14.2±6.0 W; and HDF8, 14.5±4.3 W). Small-molecule and phosphate removal were superior during long treatments. β2-Microglobulin and fibroblast growth factor 23 (FGF-23) reduction ratios were highest in HDF8.


CONCLUSIONS
Small sample size, only acute effects were studied.


CONCLUSIONS
Treatment time, and not modality, was the determinant for the hemodynamic response. HDF significantly improved removal of middle molecules, with superior results in extended HDF.
Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Centre, Maastricht, the Netherlands. Electronic address: tom.cornelis@mumc.nl.
Tom
T
Cornelis
Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Centre, Maastricht, the Netherlands.
Frank M
FM
van der Sande
Nephrology Section, Department of Internal Medicine, Ghent University Hospital, Ghent, Belgium.
Sunny
S
Eloot
Central Diagnostic Laboratory, Maastricht University Medical Centre, Maastricht, the Netherlands.
Eline
E
Cardinaels
Central Diagnostic Laboratory, Maastricht University Medical Centre, Maastricht, the Netherlands.
Otto
O
Bekers
Central Diagnostic Laboratory, Maastricht University Medical Centre, Maastricht, the Netherlands.
Jan
J
Damoiseaux
Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Centre, Maastricht, the Netherlands.
Karel M
KM
Leunissen
Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Centre, Maastricht, the Netherlands.
Jeroen P
JP
Kooman
D000328:Adult; D000368:Aged; D002302:Cardiac Output / Q000502:physiology; D018592:Cross-Over Studies; D005260:Female; D000089703:Fibroblast Growth Factor-23; D017583:Hemodiafiltration / Q000379:methods* / Q000639:trends; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods / Q000639:trends; D016037:Single-Blind Method; D013997:Time Factors; D014511:Uremia / Q000628:therapy* / Q000652:urine*
HD/HDF session duration; Hemodialysis (HD); end stage-renal disease (ESRD); extended; hemodiafiltration (HDF); hemodynamic analysis; hemodynamic stability; intensive; uremic toxin