Blood pressure, volume, and sodium control in an automated peritoneal dialysis population.
OBJECTIVE
To examine the control of blood pressure and volume, and the role of sodium removal in a single, large, contemporary, automated peritoneal dialysis (APD) population where icodextrin is used liberally and there is a policy to avoid long duration glucose-based daytime dwells.


METHODS
Observational cross-sectional study.


METHODS
A university hospital.


METHODS
56 APD patients, with a mean duration on peritoneal dialysis of 1.9 years; 50% were prescribed icodextrin.


METHODS
Blood pressure, extracellular water volume (ECW)-to-intracellular water volume (ICW) ratio, and total (peritoneal and urinary) sodium removal.


RESULTS
Sodium Removal: Mean total sodium removal, while low at 102.9 +/- 64.6 mmol/day, showed a wide range, with 41% having a sodium removal of >120 mmol/day. Total sodium removal correlated with total body water, ECW, and ICW (p < 0.001, p < 0.001, p < 0.025, respectively), as well as with height and weight (p < 0.06, p < 0.01 respectively). On multivariate analysis, only ultrafiltration volume and urine volume were significantly associated with total sodium removal (r(2) = 0.67, p < 0.0001 for both). There was also a correlation between sodium removal and urea nitrogen appearance (r(2) = 0.31, p < 0.001), with urea nitrogen appearance in turn being closely correlated with ICW (p < 0.001). Volume Status: The ECW/ICW ratio was 0.88 +/- 0.17, which was not significantly different to that found in hemodialysis patients without clinical evidence of fluid overload, either predialysis (0.96 +/- 0.16) or postdialysis (0.92 +/- 0.16); p = 0.07 and 0.36 respectively. Blood Pressure: Mean +/- standard deviation systolic blood pressure (BP) was 111.9 +/- 18.2 mmHg and diastolic BP was 63.3 +/- 11.9 mmHg, with only 4 (7%) patients having a systolic BP > 140 mmHg and 1 (2%) having a diastolic BP > 80 mmHg. Median number of antihypertensives was 1 per day. Blood pressure control and ECW/ICW ratio were similar in those with sodium removal >120 mmol/day compared to those with sodium removal < or =120 mmol/day (p = 0.39 for SBP, p = 0.70 for diastolic BP, p = 0.24 for ECW/ICW).


CONCLUSIONS
We have shown that good blood pressure and volume control is achievable in a large contemporary APD population with liberal use of icodextrin and avoidance of long daytime glucose-based dwells. Neither low nor high sodium removal was associated with more frequent hypertension or volume expansion.
Boudville
Neil C
NC
University of Western Australia, Perth, WA, Australia. nboudvil@cyllene.uwa.edu.au
Cordy
Peter
P
Millman
Kristie
K
Fairbairn
Laura
L
Sharma
Ajay
A
Lindsay
Robert
R
Blake
Peter G
PG
D000328:Adult; D001202:Ascitic Fluid / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D001810:Blood Volume / Q000502:physiology*; D001834:Body Water / Q000502:physiology; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000378:metabolism / Q000503:physiopathology* / Q000628:therapy* / Q000652:urine; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects; D012964:Sodium / Q000097:blood* / Q000652:urine
D012964:Sodium