Continuous, online measurement of the absolute plasma refill rate during hemodialysis using feedback regulated ultrafiltration: preliminary results.
Methods to continuously measure absolute refill during dialysis are not available. It would be useful to have such a method because it would allow investigating the mechanism of refill the effect of interventions. We designed a feedback algorithm that adjusts ultrafiltration rate (QUF) according to hemoglobin (Hb) concentration changes in such a way that relative blood volume (BV) remains constant within a narrow target range. In this situation, the generated QUF quantitatively reflects refill. Refill patterns were studied in five hypotension prone patients. In addition, on separate occasions, we studied the effect of antiembolism stockings (AES) and infusion of hydroxy-ethylated starch (HAES) on refill in these patients. Refill during the first hour fell significantly from 21 +/- 3 ml/min to 9 +/- 2 ml/min (p < 0.05). In the second hour, refill decreased further and became zero in four out of five patients. Neither AES nor HAES measurably affected refill. The marked and rapid fall in refill in the early stages of dialysis suggests untimely depletion of the interstitial compartment and underestimation of dry weight. We propose that continuous, online measurement of refill patterns may be of value for accurate estimation of dry weight in dialysis patients.
Brummelhuis
Walter J
WJ
Department of Nephrology, University Medical Center Utrecht, The Netherlands.
van Schelven
Leonard J
LJ
Boer
Walther H
WH
D000368:Aged; D000369:Aged, 80 and over; D001810:Blood Volume; D017583:Hemodiafiltration / Q000295:instrumentation* / Q000379:methods; D015312:Hemodialysis Solutions / Q000494:pharmacology; D006454:Hemoglobins / Q000737:chemistry; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000737:chemistry; D007022:Hypotension / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D009862:Online Systems; D006435:Renal Dialysis / Q000295:instrumentation* / Q000379:methods*; D015203:Reproducibility of Results; D014462:Ultrafiltration / Q000295:instrumentation* / Q000379:methods
D015312:Hemodialysis Solutions; D006454:Hemoglobins; D006895:Hydroxyethyl Starch Derivatives