ROULA GALLAND AND
CAROL MEERS

Techniques such as dailyhemodialysis (HD), access monitoring, and computerization can improve the effectiveness of treatment and the quality of life for home HD patients. An international panel of speakers discussed innovative strategies to enhance dialysis therapy in the home environment.

Roland Schaefer, MD, the University of Muenster, Germany, presented a comparative trial of standard versus daily HD. Nine patients were followed for 3 weeks on standard HD and then for 6 weeks on daily HD with the same dialysis prescription and total weekly time. With daily HD there was a decrease in predialysis urea nitrogen (BUN) from 94 to 75 mg/dL, and in time-averaged concentration (TAC) urea from 100 to 80 mg/dL. The urea reduction ratio (URR) declined from 64% in standard HD to 42% in daily HD, with marked dampening of pre and postdialytic oscillations of BUN. Serum bicarbonate levels rose from 18.5 to 20.5 mmol/L in daily HD, while b 2 -microglobulin and phosphorus levels remained unchanged. All patients had native fistulas and there were no vascular access problems due to frequent punctures. Daily HD is safe and feasible, and the detoxification process seems to be more physiologic.

Roula Galland, MD, Association Utilisation Rein Artificiel, Lyon, France discussed quantification in standard and daily HD. Seven patients on standard HD 4 – 5 hrs x 3/week were converted to daily HD 2 – 2.5 hrs x 6/week using similar blood and dialysate flow rates, dialysate composition, and total weekly time. The mean follow-up time on daily HD is now 17 months. On daily HD urea retention is less, as shown by the diminution of predialytic peak concentration (20 vs 28 mmol/L), and TAC urea (15 vs 19 mmol/L). Reduction of TAC urea can also be obtained by increasing dialysis dose without increasing the frequency, but the clearance is flow-, membrane-, and patient-limited and the increase in the length of dialysis sessions reduces efficiency.

The decrease of time-averaged deviation (TAD) urea from 4.76 to 2.52 mmol/L makes daily HD a more physiologic method. The weekly Kt/V should not be used to compare different therapies. Instead, two other measures, eKR (continuous equivalent urea clearance) and StdKt/V (standard Kt/V), have been proposed to compare efficiencies at different dialysis frequencies. These two measures indicated that daily HD dose increased from 12.97 to 21.7 mL/min for eKR and from 2.17 to 4.02 for StdKt/V, representing almost a third of the normal renal function. Daily HD is more physiologic and more efficient than standard HD. This increased dose of dialysis may explain the clinical improvement observed with daily HD. Tomorrow, daily HD may become the standard HD schedule.

Costas Fourtounas, MD, Aretaieion University Hospital, Athens, Greece, described the application of telematics monitoring services for remote monitoring of dialysis treatments. Bidirectional communication was established between two modified dialysis machines, located in the renal unit, and a central control station in another room, using Integrated Service Digital Network (ISDN) lines. Machine-related functions, noninvasive blood pressure, heart rate, and ECG were monitored in the central control station by an observer, initially a physician and later a nurse. The observer provided teleconsultation to the renal unit staff. No major complications were observed, and data transmission was satisfactory. Studies are in progress to determine the feasibility of in-home and satellite settings.

Carol Meers BSc, RN, Kingston General Hospital at Queen’s University, Kingston, Ontario, discussed vascular access monitoring techniques that can be taught to home HD patients. Indicators of diminishing access function include: repeated cannulation difficulty, trends in increasing venous pressure, arterial insufficiency and spasm, and declining Kt/V. The reliability and validity of these parameters were evaluated in 100 in-center HD patients over a period of 28 months. Results demonstrated a sensitivity of 72.5% and a specificity of 87.8%. Patients have now been taught these techniques. Computerized documentation (using the Fresenius FDS08 program) of home treatments facilitates review of intradialytic data by the dialysis team. Modem communication using PC Anywhere Lan ® software allows monthly download of treatment data to the parent unit, where summaries of venous and arterial pressures and blood flow rates can be assessed.

Angela Swafford, RN, Lynchburg Nephrology, Inc, Lynchburg, Virginia, described methods for increasing permanent catheter survival in patients receiving nightly home HD. All catheters are placed by one radiologist. Connections to the extracorporeal circuit are through Interlink ® caps. Warfarin is prescribed to maintain an international normalized ratio (INR) in the range of 1.75 – 2.5, and urokinase 5000 U/mL is used to lock ports of poorly functioning catheters. Catheters that consistently fail to produce blood flow rates of at least 250 mL/min are replaced. Exit-site care includes cleaning with a chlorhexidine solution and a Tegaderm ® occlusive dressing. In 91.5 catheter-months, only 2 episodes of sepsis requiring catheter removal have been documented.

All of the above-described strategies significantly enhance patients’ well-being and may contribute to the success of home HD in the next millennium.