Changes in blood glucose and lactate concentrations with hemodialysis

The futility of post-haemodialysis blood glucose levels: A retrospective cohort study

BACKGROUND

Frequent blood glucose tests are performed for people with diabetes receiving haemodialysis.

OBJECTIVES

To determine the rate of out-of-range post-haemodialysis blood glucose levels that are clinically acted upon, the intervention and outcome of each intervention, and the associations between post-haemodialysis blood glucose levels and relevant clinical predictors.

DESIGN

12-month retrospective cohort medical record review in one Australian haemodialysis centre. Post-haemodialysis blood glucose levels, prehaemodialysis blood glucose levels, time of treatment, diabetes medications, intradialytic fluid removal, dialysate dextrose concentration, clinical actions, interventions, and outcomes on out-of-range blood glucose levels were retrieved.

PARTICIPANTS

22 participants with a median time receiving dialysis 3.1 years (interquartile range 2.3-4.7).

MEASUREMENTS AND RESULTS

The proportion of out-of-range post-haemodialysis blood glucose levels was 87.3% (95% confidence interval, 86.1%-88.5%). No out-of-range post-haemodialysis blood glucose levels were clinically acted upon. Out-of-range post-haemodialysis blood glucose levels were 4.6 times more likely if a higher dextrose bath was used (95% confidence interval: 3.3; 6.3. p < 0.001). The odds of the post-haemodialysis blood glucose levels increased by each 1 mmol/L. Intradialytic fluid removal, dialysate dextrose concentration, sex, dialysis time, anti-hyperglycaemic agents were also associated with out-of-range post-haemodialysis blood glucose levels.

CONCLUSION

Routine post-haemodialysis blood glucose levels testing has limited clinical utility in care for people with diabetes receiving maintenance haemodialysis. Higher dextrose dialysate may require individual titration depending on prehaemodialysis blood glucose levels.

Why is Intradialytic Hypotension the Commonest Complication of Outpatient Dialysis Treatments?

Intradialytic hypotension (IDH) is the most frequent complication of hemodialysis (HD) treatments with a frequency of 10% to 12% for patients with chronic kidney disease attending for outpatient treatments and is associated with both temporary ischemic stress to vital organs, including the heart and brain, and increased patient mortality. Although there have been many different definitions of IDH over the years, an absolute nadir systolic blood pressure (SBP) has the strongest association with patient outcomes. The unifying pathophysiology is one of reduced effective blood volume, resulting in lower plasma tonicity, and if this cannot be adequately compensated for by activation of neurohumeral systems, then arteriolar tone and blood pressure fall. The risk factors for developing IDH are numerous, ranging from patient-related factors, including age and comorbidity with reduced cardiac reserve, to patient compliance with dietary and lifestyle advice, to reactions with the extracorporeal circuit and medications, choice of dialysate composition and temperature, setting of postdialysis target weight, ultrafiltration rate, and profiling. Advances in dialysis machine technology by providing real time estimates of the effective circulating volume and adjusting dialysate composition to maintain vascular tonicity are being developed, but currently require more sophisticated biofeedback loops to be clinically effective in preventing IDH. While awaiting advances in artificial intelligence, the clinician continues to rely on patient education to limit interdialytic weight gains, frequent assessment of the postdialysis target weight, adjusting dialysate composition and temperature, introducing convective therapies to increase thermal losses, and altering dialysis session duration and frequency to reduce ultrafiltration rate requirements.

Peri-dialytic hypoglycaemia with haemodialysis and on-line post-dilutional haemodiafiltration

INTRODUCTION

We wished to determine whether peri-dialytic hypoglycaemia is a clinical risk in contemporary dialysis patients using glucose containing dialysate.

METHODS

We measured blood glucose pre- and post-haemodialysis or haemodiafiltration, using 5.5 mmol/L glucose dialysate, and body composition by bioimpedance.

RESULTS

239 patients were studied, mean age 65±15.4 years, 59.4% male, 46.4% diabetes, 81.6% treated by haemodiafiltration, Five haemodiafiltration patients (2.1%) had hypoglycaemia, with 82 (33%) a blood glucose <5.5 mmol/L, with fewer diabetics (19.8 vs 74.7%, p=0.001, and %body fat 27.7(20.6-32.6) vs 34.7(26.6-42.8)%, p=0.001. Low post-dialysis blood glucose was negatively associated with glycated haemoglobin (OR 0.94 (0.84-0.97), p=0.004), weight (OR 0.94 (0.89-0.98), p=0.009), and % body fat (OR 0.92 (0.86-0.98), p=0.013).

CONCLUSIONS

Although hypoglycaemia occurred in 2%, 33% had a blood glucose below dialysate glucose. Low post-dialysis glucose was associated with lower glycated haemoglobin and body fat, suggesting nutritional status is important in determining the risk of peri-dialytic hypoglycaemia.