Influence of the cyclic variation of hydration status on hemoglobin levels in hemodialysis patients.
BACKGROUND
Maintenance hemodialysis (HD) patients were studied to assess the effect on hemoglobin (Hb) concentration induced by the cyclic variation in hydration status.


METHODS
Forty-nine HD patients were examined in three consecutive HD sessions in a 1-week treatment period. In a subgroup of 23 patients, Hb levels also were investigated during the long interdialytic interval.


RESULTS
Hb levels at the end of the long interdialytic interval were significantly lower by 0.5 to 0.6 g/dL (5 to 6 g/L) than those at the end of short intervals. Among all pre-HD and post-HD Hb values, levels measured at the end of short intervals were closest to the mean Hb value of the week, derived from calculation of the area under the curve (12.0 +/- 0.2 g/dL [120 +/- 2 g/L]). Intradialytic Hb increments were different in the three sessions (+1.6 +/- 0.1 g/dL [+16 +/- 1 g/L] after the long interval, +1.1 +/- 0.1 g/dL [+11 +/- 1 g/L] and +1.1 +/- 0.1 g/dL [+11 +/- 1 g/L] after short intervals [P < 0.001] and proportionate to weight loss [-3.4 +/- 0.1, -2.7 +/- 0.1, and -2.6 +/- 0.1 kg, respectively; P < 0.001]). Hb level increment and weight loss correlated directly (r = 0.527; P < 0.0001); each 1 L of ultrafiltration (UF) led to an increase in Hb level of approximately 0.4 g/dL (4 g/L). Plasma refilling accounted for an approximately 45% decrement in the intradialytic increase in Hb level 2 hours post-HD.


CONCLUSIONS
This study suggests that: (1) the end of the short interdialytic period is the most appropriate timing for anemia assessment, and (2) the remarkable hemodiluting effect of post-HD plasma refilling protects against excessive increments in Hb levels induced by UF.
Nephrology-Dialysis Unit, Country Hospitals in Lauria, Polla, Ariano Irpino, Italy.
Vincenzo
V
Bellizzi
Roberto
R
Minutolo
Vincenzo
V
Terracciano
Carmela
C
Iodice
Paolo
P
Giannattasio
Luca
L
De Nicola
Giuseppe
G
Conte
Biagio R
BR
Di Iorio
D001834:Body Water / Q000502:physiology*; D004334:Drug Administration Schedule; D004909:Erythrocyte Indices / Q000187:drug effects; D004921:Erythropoietin / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D006973:Hypertension / Q000517:prevention & control; D007279:Injections, Subcutaneous; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011994:Recombinant Proteins; D006435:Renal Dialysis; D013927:Thrombosis / Q000517:prevention & control; D013997:Time Factors; D014554:Urination / Q000502:physiology
D006454:Hemoglobins; D011994:Recombinant Proteins; D004921:Erythropoietin