Adjusting Fluid Removal Based on Blood Volume in Hemodialysis: A Randomized Study

Blood Volume Monitoring Guided Ultrafiltration Biofeedback on Reduction of Intra-dialytic Hypotensive Episodes in Hemodialysis: A Randomized Cross Over Study

As kidney function declines, the ability to maintain water balance is impaired and is most often treated with hemodialysis. The removal of excess water in hemodialysis often leads to a sudden drop of blood pressure and causes symptoms of dizziness, light-headedness, cramping, and chest pain. This sudden drop in blood pressure has been linked with complications of heart attacks, strokes and even death. Research has focused on different ways to prevent dangerous drops in blood pressure during hemodialysis. One way is the use of blood volume monitoring biofeedback technology to monitor the patient's relative blood volume and automatically reduce the amount of fluid that is being removed when the blood volume is low to prevent the drop in blood pressure from occurring. This type of biofeedback device is currently available on some hemodialysis machines and while this approach appealing, it is not clear how effective this form of biofeedback is in preventing the drops in blood pressure.

We plan to determine if the use of biofeedback based on the changes in the patient's blood volume will reduce the number of sudden drops in blood pressure that occur during hemodialysis. To do this, we will compare patients treated with this technology to current hemodialysis practices and follow them for important adverse outcomes. The result of interest will be the frequency of hemodialysis sessions complicated by a sudden symptomatic drop in blood pressure. We also plan to monitor the amount of water in the different body compartments, blood pressure, blood pressure medication use, markers of heart function, and patient symptoms and quality of life.

We hope that by providing information on this technology we can reduce the sudden drops in blood pressure in hemodialysis, the associated rates of serious disease or death, and improve patient quality of life.

Study Overview

• Status: Completed
• Conditions: End Stage Renal Failure on Dialysis; Intradialytic Hypotension
• Intervention / Treatment: Device: Fresenius 5008 HD machine (Fresenius Medical Care, Bad Homburg, Germany); Device: BVM-UF biofeedback

Detailed Description

This is a 22 week parallel group, randomized crossover trial to determine the effect of blood volume monitoring, BVM, guided ultrafiltration (UF) biofeedback on symptomatic intradialytic hypotension (IDH) episodes amongst IDH prone patients. The first part of the study (Part 1 - Run-In/Dialysis Optimization Phase), eligible patients will undergo a four-week run-in phase. During this period all patients will undergo a comprehensive clinical assessment including, clinical weight assessment, anti-hypertensive medication review, and dialysis prescription standardization. At the end of the run-in phase, patients that still meet eligibility criteria will enter the randomized cross-over phase. In part 2 (Randomized Cross-Over Phase), patients are randomized to regular best clinical practice hemodialysis, HD (without BVM-guided UF biofeedback; control arm) or to BVM-guided UF biofeedback (intervention arm) for an 8 week period. This will be followed by a two-week washout phase and then patients will be crossed over for a second 8-week phase. The study will be conducted and reported following the Consolidated Standards of Reporting Trials (CONSORT) 2010 guidelines.

• Study Type: Interventional
• Enrollment (Actual): 34
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Calgary, Alberta, Canada, T2N 2T9
      • Alberta Health Services Southern Alberta Renal Program

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Run-in Phase Inclusion Criteria:

• >18 years old
• Maintenance hemodialysis patients for more than 3 months
• Undergo hemodialysis 3-4 times per week for a minimum of three hours per session
• Have >30% of their hemodialysis sessions in the preceding 8 weeks complicated by symptomatic IDH.
• Able to provide written informed consent.

Randomization Phase Inclusion Criteria:

• >18 years old
• Maintenance hemodialysis patients for more than 3 months
• Undergo hemodialysis 3-4 times per week for a minimum of three hours per session
• Have >30% of their hemodialysis sessions in the preceding 4 weeks complicated by symptomatic IDH.

Exclusion Criteria:

• Serum sodium ≤133mmol/L
• Hemoglobin <80g/L
• Active Malignancy
• History of blood transfusions or hospitalizations in the preceding 4 weeks
• Planned change in the renal replacement modality during the planned study period

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Best clinical practice HD; All study patients will be dialyzed with the Fresenius 5008 HD machine (Fresenius Medical Care, Bad Homburg, Germany) using high flux dialyzers. For an 8-week period, patients in the best clinical practice (control) phase will use their same prescription as the run-in phase, dialysate sodium of 138mmol/L, dialysate calcium of 1.25mmol/L, dialysate temperature of 36oC, and constant UF rate. BVM will be disabled in this group.	Device: Fresenius 5008 HD machine (Fresenius Medical Care, Bad Homburg, Germany); For an 8-week period, patients in the best clinical practice (control) phase will use their same prescription as the run-in phase, dialysate sodium of 138mmol/L, dialysate calcium of 1.25mmol/L, dialysate temperature of 36oC, and constant UF rate. BVM will be disabled in this group.
Experimental: Best clinical practice plus BVM-guided UF biofeedback; Patients in the BVM-guided UF biofeedback (intervention) phase will have the same prescription as the control group but will also have the ultrafiltration rate automatically adjusted by the Fresenius 5008 HD machine based on the changes in the relative blood volume.	Device: Fresenius 5008 HD machine (Fresenius Medical Care, Bad Homburg, Germany); For an 8-week period, patients in the best clinical practice (control) phase will use their same prescription as the run-in phase, dialysate sodium of 138mmol/L, dialysate calcium of 1.25mmol/L, dialysate temperature of 36oC, and constant UF rate. BVM will be disabled in this group.; Device: BVM-UF biofeedback; The Fresenius 5008 uses an ultrasound and temperature monitor incorporated into the machine to detect ultrasonic velocity and temperature changes to derive the total protein concentration, which is a sum of total plasma proteins and hemoglobin. The relative blood volume is calculated at by dividing the initial concentration of total protein by the total protein concentration at any given time, multiplied by 100. The HD software is based on the critical blood volume entered at the beginning of the dialysis session for each individual patient. The UF rate is adjusted based on the changes in the relative blood volume to the patient's critical relative blood volume.; Other Names: Fresenius 5008 HD machine with UF control

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the rate of symptomatic IDH during hemodialysis	The primary outcome will be rate of symptomatic IDH as defined by an abrupt drop in the systolic blood pressure of ≥20mm Hg when compared to baseline along with an abrupt onset headache, dizziness, unconsciousness, thirst, dyspnea, angina, muscle cramps, or vomiting (reflecting cerebral, cardiac, gastrointestinal, or musculoskeletal ischemia). The end of an episode of IDH will be defined as resolution of the symptom. The number of symptomatic IDH episodes along with the duration of each dialysis treatment will be captured. The rate of IDH for each session will be calculated by dividing the number of episodes by the duration of the session in hours. The rate of IDH will be calculated for every dialysis treatment. The rate of symptomatic IDH will be measured in the two months preceding enrollment, during each phase of the study.	During hemodialysis up to the 22 week study period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the number of symptomatic IDH per dialysis session	The number of symptomatic IDH episodes in each dialysis treatment will be captured. IDH is defined as in the primary outcome.	During hemodialysis up to the 22 week study period
Change in the frequency of symptomatic IDH	The number of symptomatic IDH episodes of each dialysis treatment will be captured. IDH is defined as in the primary outcome.	During hemodialysis up to the 22 week study period
Number and Frequency of Nursing Interventions during hemodialysis	IDH-related nursing interventions are defined as the use of Trendelenburg/supine position, discontinuation of UF, fluid/saline challenge, return of blood, shortened dialysis run, or prolonged (more than 15 minutes) post-dialysis recovery period as a result of IDH or its symptoms. Given the subjective nature of IDH-related symptoms and intervention, in-services and customized dialysis run sheets will be provided to all nurses at participating dialysis centers to ensure that all events are recorded and recorded consistently. The number of symptomatic IDH episodes per session will be record.	During hemodialysis up to the 22 week study period
Change in Single Session Dialysis Adequacy	Patients that experience symptomatic IDH may require a reduction in the duration of HD treatments with a resultant reduction in dialysis adequacy. Dialysis adequacy will be measured and recorded (usual care) at the end of each dialysis session on the session sheet as single-pooled Kt/V. Single-pooled Kt/v is measured using the previously validated online clearance measurement method, which detects changes in conductivity in the dialysate to reflect the clearance of serum electrolytes and urea.	After hemodialysis up to the 22 week study period
Electrical Bio-impedance for the determination of change in hydration and fluid status	Whole body and segmental bio-impedance analysis for the determination of fluid composition has been validated in HD patients. Improvement of dry weight has been linked with reduced mortality. Electrical bio-impedance will be performed at the end of the mid-week HD session at week 1, 4, 8, 12, 14, 18, and 22 to determine the total body water, extracellular fluid volume (ECFV), intracellular fluid volume (ICFV), and the ECFV:ICFV ratio.	At the end of the mid-week HD session at week 1, 4, 8, 12, 14, 18, and 22. Up to week 22 study period.
Change in Serum Brain Natriuretic Peptide (BNP)	Chronic hypervolemia in HD is associated with increase in left atrial volume and BNP, which has been shown to predict mortality. Serum BNP will be measured at the beginning of the mid-week HD session at week 1, 4, 12, 14, and 22.	At the beginning of the mid-week HD session at week 1, 4, 12, 14, and 22. Up to week 22 study period.
Change in Serum high sensitivity cardiac troponin (hs-Troponin)	Biomarkers of cardiac damage such as hs-Troponin are more elevated in HD patients with myocardial stunning and is associated with an increased all-cause mortality. Improved and more frequent dialysis has been associated with a decrease in myocardial stunning, and a trend towards decreasing hs-troponin. Serum hs-Troponin will be performed at the beginning of the mid-week HD session at week 1, 4, 12, 14, and 22.	At the beginning of the mid-week HD session at week 1, 4, 12, 14, and 22. Up to week 22 study period.
Change in antihypertensive medication use	Improvements in a patient's volume status and blood pressure allows for a decrease number or dose of anti-hypertensive medications. The class and number of anti-hypertensive medications will be obtained from the electronic clinical database and subsequently confirmed with a patient interview at enrollment and the mid-week HD session at week 4, 8, 12, 14, 18, and 22. The study investigator will perform medication reconciliation	At enrollment and the mid-week HD session at week 4, 8, 12, 14, 18, and 22.
Relative blood volume Curve	The shape and slope of the RBV curve has been associated with symptomatic hypotensive episodes in HD. The relative blood volume curve will be downloaded from the Fresenius 5008 dialysis machine to a study computer on a regular basis for all patients in the run-in phase and those in the intervention arm following randomization. The relative blood volume achieved, maximum slope (%/h) of the BVM curve as defined by the percent (%) decline over time (h) will be calculated. The subjective pattern of BVM curve (flat, linear, concave upward, concave downward, regular and irregular line will be determined by the study investigator.	After every hemodialysis session, up to the 22 week study period.
Improvement in Intra-dialytic symptom survey	Currently no validated intra-dialytic symptom survey exists to provide an objective measure of intra-dialytic symptom burden. The survey will inquire about the intra-dialytic symptoms of IDH, specifically nausea, vomiting, chest pain, shortness of breath, headache, muscle cramps, dizziness, fainting, fatigue, and anxiety. The survey will be provided by the dialysis nurse, and to be completed by the patient or in conjunction with the dialysis nurse at the end of the dialysis session during weeks 1, 4, 8, 12, 14, 18, and 22. The survey is expected to take less than 1 minute to complete.	At the end of each dialysis session, during weeks 1, 4, 8, 12, 14, 18, and 22. Up to the 22 week study period.
Improvement in Inter-dialytic symptom survey	A survey inquiring about inter-dialytic recovery time to baseline will be provided by the dialysis nurse, and to be completed by the patient or in conjunction with the dialysis nurse at the beginning of dialysis during weeks 1, 4, 8, 12, 14, 18, and 22. The survey will inquire the time it took the patient to recovery from the last dialysis session, is validated in HD patients as a robust assessment quality of life. The survey will take less than 30 seconds to complete.	At the beginning of each dialysis session, during weeks 1, 4, 8, 12, 14, 18, and 22. Up to the 22 week study period.
Assessment of Nursing Perception, Attitudes, and Satisfaction of BVM guided UF biofeedback system	A survey inquiring about nursing perception and attitudes of the BVM guided UF biofeedback will be provided to the nurses at the end of the control and intervention phase. The survey is developed for the purpose of this study.	At the end of the control and intervention phase (end of week 12 and 22). Up to the 22 week study period.

Collaborators and Investigators

• Sponsor: University of Calgary
• Investigators: Study Director: Robert Quinn, MD PhD, University of Calgary; Study Director: Kelvin Leung, MD, University of Calgary; Principal Investigator: Jennifer MacRae, MD MSc, University of Calgary

Publications and helpful links

General Publications

• Wizemann V, Wabel P, Chamney P, Zaluska W, Moissl U, Rode C, Malecka-Masalska T, Marcelli D. The mortality risk of overhydration in haemodialysis patients. Nephrol Dial Transplant. 2009 May;24(5):1574-9. doi: 10.1093/ndt/gfn707. Epub 2009 Jan 7.
• Velasco N, Chamney P, Wabel P, Moissl U, Imtiaz T, Spalding E, McGregor M, Innes A, MacKay I, Patel R, Jardine A. Optimal fluid control can normalize cardiovascular risk markers and limit left ventricular hypertrophy in thrice weekly dialysis patients. Hemodial Int. 2012 Oct;16(4):465-72. doi: 10.1111/j.1542-4758.2012.00689.x. Epub 2012 Apr 20.
• Shoji T, Tsubakihara Y, Fujii M, Imai E. Hemodialysis-associated hypotension as an independent risk factor for two-year mortality in hemodialysis patients. Kidney Int. 2004 Sep;66(3):1212-20. doi: 10.1111/j.1523-1755.2004.00812.x.
• Selby NM, McIntyre CW. The acute cardiac effects of dialysis. Semin Dial. 2007 May-Jun;20(3):220-8. doi: 10.1111/j.1525-139X.2007.00281.x.
• Schreiber MJ Jr. Setting the stage. Am J Kidney Dis. 2001 Oct;38(4 Suppl 4):S1-S10. doi: 10.1053/ajkd.2001.28089.
• Schneditz D, Pogglitsch H, Horina J, Binswanger U. A blood protein monitor for the continuous measurement of blood volume changes during hemodialysis. Kidney Int. 1990 Aug;38(2):342-6. doi: 10.1038/ki.1990.207. No abstract available.
• Schmidt R, Roeher O, Hickstein H, Korth S. Prevention of haemodialysis-induced hypotension by biofeedback control of ultrafiltration and infusion. Nephrol Dial Transplant. 2001 Mar;16(3):595-603. doi: 10.1093/ndt/16.3.595.
• Davenport A. Using dialysis machine technology to reduce intradialytic hypotension. Hemodial Int. 2011 Oct;15 Suppl 1:S37-42. doi: 10.1111/j.1542-4758.2011.00600.x.
• Daugirdas JT. Dialysis hypotension: a hemodynamic analysis. Kidney Int. 1991 Feb;39(2):233-46. doi: 10.1038/ki.1991.28. No abstract available.
• Dasselaar JJ, Huisman RM, DE Jong PE, Franssen CF. Relative blood volume measurements during hemodialysis: comparisons between three noninvasive devices. Hemodial Int. 2007 Oct;11(4):448-55. doi: 10.1111/j.1542-4758.2007.00216.x.
• Agarwal R, Kelley K, Light RP. Diagnostic utility of blood volume monitoring in hemodialysis patients. Am J Kidney Dis. 2008 Feb;51(2):242-54. doi: 10.1053/j.ajkd.2007.10.036.
• Agarwal R. Hypervolemia is associated with increased mortality among hemodialysis patients. Hypertension. 2010 Sep;56(3):512-7. doi: 10.1161/HYPERTENSIONAHA.110.154815. Epub 2010 Jul 12.
• Leung KC, Quinn RR, Ravani P, MacRae JM. Ultrafiltration biofeedback guided by blood volume monitoring to reduce intradialytic hypotensive episodes in hemodialysis: study protocol for a randomized controlled trial. Trials. 2014 Dec 10;15:483. doi: 10.1186/1745-6215-15-483.

Study record dates

Study Major Dates

• Study Start: June 1, 2014
• Primary Completion (Actual): June 1, 2015
• Study Completion (Actual): June 1, 2015

Study Registration Dates

• First Submitted: November 6, 2013
• First Submitted That Met QC Criteria: November 13, 2013
• First Posted (Estimate): November 20, 2013

Study Record Updates

• Last Update Posted (Estimate): July 27, 2015
• Last Update Submitted That Met QC Criteria: July 24, 2015
• Last Verified: July 1, 2015

More Information

Terms related to this study

• Keywords: Renal Dialysis; Clinical Trials, Randomized; Intradialytic Hypotension; Crossover Studies; Blood Volume Determination
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Kidney Diseases; Urologic Diseases; Renal Insufficiency; Renal Insufficiency, Chronic; Kidney Failure, Chronic; Hypotension
• Other Study ID Numbers: BVM-RXOS