Renal Perfusion during Hemodialysis: Intradialytic Blood Flow Decline and Effects of Dialysate Cooling

Abstract

BackgroundResidual 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.MethodsWe 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.ResultsDuring 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.ConclusionsThis 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.

Blood pressure and volume management in dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

“…3,82 Although no RCTs have demonstrated that lowering UF rates improves outcomes, biologic plausibility data support a relationship between higher UF rates and end-organ ischemia (heart, brain, liver, gut, kidneys). [83][84][85][86][87][88][89] A critical unanswered question is how to balance the potential risks from higher UF rates with the potential risks from volume overload. 80 In the absence of conclusive data, using one specific UF rate threshold for all patients at all times is likely inappropriate.…”

Successful Anesthesia Management in a Patient With Type A Aortic Dissection Complicated by Renal Failure and Suspected Coronavirus Disease

“…The ultrafiltration technology used in this study not only salvages blood, but also protects the brain and heart from ischemic injury. 11 After the emergency operation, the patient was transferred to a designated negative pressure isolation unit for individual monitoring. Specific postoperative management strategies should strictly follow the infection precaution guidelines, including maintaining hemodynamic stability, electrolyte balance, punctual hemodialysis, infection control, and other treatment programs.…”

“…A statistical interaction suggested for acute kidney injury, and the protective effects deep hypothermia could be attenuated by the prolonged CPB time. 11 Because COVID-19 can cause hypoxia in tissues and organs and the 3-level protection requirements may lead to increased operating times for surgeons, this will prolong the CPB time to aggravate organ damage.…”

Dialysis-Induced Cardiovascular and Multiorgan Morbidity

“…62 Importantly, dialysis has negative effects not only on the perfusion of the heart but also on other organs, such as kidney, gut, liver, and brain, as shown by various imaging techniques of positron emission tomography, computed tomography, and MRI. [63][64][65] Apart from direct organ damage by tissue ischemia, hepatosplanchnic circulatory stress may also induce bacterial translocation, endotoxin release, and the increased release of gut-derived uremic toxins such as indoxyl sulphate into the systemic circulation. [66][67][68][69] The importance of these observations is shown by studies reporting an association between mortality and ultrafiltration rate/volume and change in blood pressure and end-organ ischemic injury.…”