Effect of blood volume change related to intensity of intradialytic aerobic exercise on hemodialysis adequacy: a pilot study

PURPOSE

Intradialytic exercise may improve dialysis efficiency; however, the association between changes in blood volume (BV) related to exercise intensity and solute removal kinetics remains unknown. We herein investigated the relationship between changes in BV with exercise and removal of solute molecules during hemodialysis.

METHODS

Each of the 21 hemodialysis patients underwent cardiopulmonary exercise test to measure anaerobic threshold (AT). According to the exercise intensity, patients were classified into two groups, the low group (n = 12), whose intensity was below the AT, and the high group (n = 9), whose intensity was at the AT level. Each patient completed two trial arms of resting and discontinuous exercise dialysis sessions in a randomized manner.

RESULTS

The change in BV with the exercise dialysis session in the high group decreased during exercise (p = 0.028) and remained decreased after exercise (p = 0.016), compared with the low group. In the low group, compared with routine sessions, the removal of potassium (p = 0.030), phosphate (p = 0.024), and urea nitrogen (p = 0.065) increased during exercise, but the total removal of these solutes did not change. In the high group, the removal of phosphate (p < 0.001) and urea nitrogen (p = 0.018) after exercise and even total phosphate (p = 0.027) decreased.

CONCLUSION

These findings suggest that the removal of small solute molecules is improved during exercise in intradialytic low-intensity exercise with no change in BV, and decreased after exercise in high-intensity exercise with a decrease in BV.

CLINICAL TRIALS REGISTRY

Trial retrospectively registered at the UMIN Clinical Trials Registry: study number UMIN000038629 (Registration date: September 7, 2019).

Factors affecting inadequate response to HBV vaccine in hemodialysis patients: northeast anatolia survey with six hemodialysis centers

BACKGROUND

In hemodialysis patients Hepatitis B virus (HBV) infection is one of the problems. Because of HBV vaccine response is lower than in the general population, in this study it is aimed to determine the factors that may cause inadequate HBV vaccine response in hemodialysis patients.

METHODS

In study, HBsAg, anti-HBs, anti-HBc IgG data belonging to 278 patients were obtained from file and computer records. It was seen that seronegative cases had been given recombinant HBV vaccine. Anti-HBs titers were monitored 1 month after vaccination was completed. According to this, the patients are divided into two groups. Those with anti-HBs < 10 IU/mL were identified as non-responders and with anti-HBs ≥ 10 IU/mL as responders. Factors such as age, serum albumin and urea reduction rate which may affect inadequate response to HBV vaccine were evaluated. As statistical examination, Chi-square test was used for the analysis of the data determined by counting, and logistic regression was used for statistically significant independent variables in chi-square test. p value of < 0.05 was considered statistically significant (Confidence interval: 95%).

RESULTS

Out of 278 patients, according to exclusion criteria 81 patients were excluded. 13.2%(26/197) of HBV vaccinated patients had insufficient response. The inadequate response rate to HBV vaccination was found to be higher in patients with age ≥ 65 (p = 0.039), serum albumin < 3.5 g/dL (p = 0.024) and urea reduction rate ≤ 65 (p = 0.028). No statistically significant relationship was found between inadequate response to HBV vaccine and anti-HCV positivity, presence of diabetes mellitus, anemia status, vitamin D therapy and vascular access pathway variability.

CONCLUSION

We conclude that relatively high patient age, low albumin level and insufficient urea reduction rate may cause inadequate HBV vaccine response. Taking these factors into consideration may provide a useful insight for an adequate response to vaccination.

Blood Urea Nitrogen Stability: A Feasibility Study for Home Hemodialysis Adequacy Testing Through Mail

Urea kinetic modeling measures the delivered dose of hemodialysis and is used to monitor dialysis adequacy. Obtaining samples for adequacy calculations is a challenge for home hemodialysis (HHD) patients. Ideally, the urea reduction ratio (URR) should be measured at a typical dialysis session; therefore, for HHD patients test specimens should be drawn at home and transferred to a clinical laboratory. Would blood urea nitrogen (BUN) remain stable if samples were mailed to the laboratory? To answer this question, BUN was measured in pre- and postdialysis samples from 20 patients over 8 days of laboratory storage. While BUN values varied among the patient population, neither pre- nor postdialysis values showed any significant variation during the 8-day storage time. These results suggest that BUN values are sufficiently stable for specimens to be drawn at home and mailed to a testing laboratory.