Prevention of dialysis hypotension episodes using fuzzy logic control system

• Published in: Nephrology, dialysis, transplantation Vol. 22; no. 5; pp. 1420 - 1427
• Main Authors: Mancini, Elena, Mambelli, Emanuele, Irpinia, Mina, Gabrielli, Danila, Cascone, Carmelo, Conte, Ferruccio, Meneghel, Gina, Cavatorta, Fosco, Antonelli, Alessandro, Villa, Giuseppe, Canton, Antonio Dal, Cagnoli, Leonardo, Aucella, Filippo, Fiorini, Fulvio, Gaggiotti, Enzo, Triolo, Giorgio, Nuzzo, Vitale, Santoro, Antonio
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.05.2007; Oxford Publishing Limited (England)
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; biofeedback control; Biofeedback, Psychology - physiology; Biological and medical sciences; blood pressure; Blood Pressure - physiology; dialysis hypotension; Emergency and intensive care: renal failure. Dialysis management; Female; fuzzy control; Fuzzy Logic; Glomerulonephritis; haemodynamics; Humans; Hypotension - etiology; Hypotension - prevention & control; Hypotension - psychology; Intensive care medicine; Kidney Failure, Chronic - physiopathology; Kidney Failure, Chronic - psychology; Kidney Failure, Chronic - therapy; Male; Medical sciences; Middle Aged; Nephrology. Urinary tract diseases; Nephropathies. Renovascular diseases. Renal failure; Prospective Studies; Renal Dialysis - adverse effects; Renal Dialysis - instrumentation; Renal Dialysis - methods; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the urinary system; fuzzy control; blood pressure; dialysis hypotension; biofeedback control; haemodynamics; Kidney disease; Urinary system disease; Hemodialysis; Fuzzy logic; Prevention; Extrarenal dialysis; Renal failure; Arterial pressure; Biofeedback; Dialysis; Blood pressure; Hemodynamics
• ISSN: 0931-0509; 1460-2385
• DOI: 10.1093/ndt/gfl799

Background. Automatic systems for stabilizing blood pressure (BP) during dialysis are few and only control those variables indirectly related to BP. Due to complex BP regulation under dynamic dialysis conditions, BP itself appears to be the most consistent input parameter for a device addressed to preventing dialysis hypotension (DH). Methods. An automatic system (ABPS, automatic blood pressure stabilization) for BP control by fluid removal feedback regulation is implemented on a dialysis machine (Dialog Advanced, Braun). A fuzzy logic (FL) control runs in the system, using instantaneous BP as the input variable governing the ultrafiltration rate (UFR) according to the BP trend. The system is user-friendly and just requires the input of two data: critical BP (individually defined as the possible level of DH risk) and the highest UFR applicable (percentage of the mean UFR). We evaluated this system's capacity to prevent DH in 55 RDT hypotension-prone patients. Sessions with (treatment A) and without (treatment B) ABPS were alternated one-by-one for 30 dialysis sessions per patient (674 with ABPS vs 698 without). Results. Despite comparable treatment times and UF volumes, severe DH appeared in 8.3% of sessions in treatment A vs 13.8% in treatment B (−39%, P = 0.01). Mild DH fell non-significantly (−12.3%). There was a similar percentage of sessions in which the planned body weight loss was not achieved and dialysis time was prolonged. Conclusions. In conclusion, FL may be suited to interpreting and controlling the trend of a determined multi-variable parameter like BP. The medical knowledge of the patient and the consequent updating of input parameters depending on the patient's clinical conditions seem to be the main factors for obtaining optimal results.