Effect of hemodialysis on the thickness of vocal folds: a possible explanation for postdialysis hoarseness.
BACKGROUND
Determining the dry weight of chronically hemodialysed patients is a common problem. Patients on intermittent hemodialysis often experience transient hoarseness at the end of dialysis. The vocal folds may be affected by the hydration state.


OBJECTIVE
To test the hypothesis that postdialysis hoarseness may be related to changes in the thickness of the vocal folds.


METHODS
Twenty-five stable chronic hemodialysis patients underwent endoscopic nasopharyngeal laryngoscopy before and after dialysis. Pictures of the vocal folds were taken and the folds were measured using computer software. Eighteen vocal folds from 16 patients were technically adequate for analysis. The change in the width/length ratio of the vocal folds (W/L) was used as a measurement of the folds' thickness.


RESULTS
W/L decreased from 0.175 +/- 0.011 before dialysis to 0.152 +/- 0.009 after dialysis (p < 0.01, mean reduction 10.9 +/- 3.8%). Patients' weight decreased by 4.7 +/- 0.3% (p < 0.0001), systolic blood pressure decreased by 15.0 +/- 3.1% (p < 0.001), diastolic blood pressure decreased by 13.0 +/- 3.6% (p < 0.01), and mean blood pressure decreased by 14.1 +/- 3.1% (p < 0.001). Sixty percent of the patients had postdialysis hoarseness, and in 72% of the patients a decrease in the vocal folds' thickness was observed.


CONCLUSIONS
Chronic hemodialysis patients may experience transient postdialysis hoarseness, and a decrease in the vocal folds' thickness. The latter may result from dehydration.
Ori
Yaacov
Y
Department of Nephrology, Rabin Medical Center (Hasharon Hospital), Petah-Tikva, Israel.
Sabo
Reni
R
Binder
Yuval
Y
Weinstein
Talia
T
Korzets
Asher
A
Ori
Gilad
G
Gafter
Uzi
U
Chagnac
Avry
A
D000328:Adult; D000368:Aged; D001794:Blood Pressure; D003681:Dehydration / Q000150:complications*; D005260:Female; D006685:Hoarseness / Q000209:etiology* / Q000473:pathology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects*; D014827:Vocal Cords / Q000473:pathology*; D014833:Voice Quality