Renal Perfusion during Hemodialysis: Intradialytic Blood Flow Decline and Effects of Dialysate Cooling.
BACKGROUND
Residual renal function (RRF) confers survival in patients with ESRD but declines after initiating hemodialysis. Previous research shows that dialysate cooling reduces hemodialysis-induced circulatory stress and protects the brain and heart from ischemic injury. Whether hemodialysis-induced circulatory stress affects renal perfusion, and if it can be ameliorated with dialysate cooling to potentially reduce RRF loss, is unknown.


METHODS
We used renal computed tomography perfusion imaging to scan 29 patients undergoing continuous dialysis under standard (36.5°C dialysate temperature) conditions; we also scanned another 15 patients under both standard and cooled (35.0°C) conditions. Imaging was performed immediately before, 3 hours into, and 15 minutes after hemodialysis sessions. We used perfusion maps to quantify renal perfusion. To provide a reference to another organ vulnerable to hemodialysis-induced ischemic injury, we also used echocardiography to assess intradialytic myocardial stunning.


RESULTS
During standard hemodialysis, renal perfusion decreased 18.4% (P<0.005) and correlated with myocardial injury (r=-0.33; P<0.05). During sessions with dialysis cooling, patients experienced a 10.6% decrease in perfusion (not significantly different from the decline with standard hemodialysis), and ten of the 15 patients showed improved or no effect on myocardial stunning.


CONCLUSIONS
This study shows an acute decrease in renal perfusion during hemodialysis, a first step toward pathophysiologic characterization of hemodialysis-mediated RRF decline. Dialysate cooling ameliorated this decline but this effect did not reach statistical significance. Further study is needed to explore the potential of dialysate cooling as a therapeutic approach to slow RRF decline.
['Marants|Raanan|R|', 'Qirjazi|Elena|E|', 'Grant|Claire J|CJ|', 'Lee|Ting-Yim|TY|', 'McIntyre|Christopher W|CW|']
D000328:Adult D000368:Aged D000369:Aged, 80 and over D000704:Analysis of Variance D003080:Cold Temperature D018592:Cross-Over Studies D015314:Dialysis Solutions D005260:Female D005500:Follow-Up Studies D006801:Humans D007668:Kidney D007677:Kidney Function Tests D008297:Male D008875:Middle Aged D010477:Perfusion D012039:Regional Blood Flow D006435:Renal Dialysis D051436:Renal Insufficiency, Chronic D012189:Retrospective Studies D012720:Severity of Illness Index D013997:Time Factors D014057:Tomography, X-Ray Computed
hemodialysis renal function decline renal hemodynamics renal ischemia