Hildegard Hafner-Giessauf

Intracorporeal glucose disposal during hemodialysis after a standardized glucose load.

The aim of this study was to quantify intracorporeal clearance and disposal of glucose after the administration of a standardized glucose load during regular hemodialysis done in stable and non-diabetic patients and to account for effects of extracorporeal clearance. A standardized load of glucose was administered ∼30 min after starting hemodialysis with a constant dialysate glucose of 5.0 ± 0.2 mmol/L. Glucose in the arterial line blood and in dialysate outflow was measured at baseline and in short intervals for a period of 1 h after the infusion. Tests were repeated within 1 week. Nine patients completed the study. Extracorporeal blood and dialysate flows were 304 ± 34 and 500 mL/min, respectively. The intracorporeal clearance of glucose was 327 ± 137 mL/min and 69.1 ± 9.4% of total glucose clearance. Mass balance assessed from dialysate samples showed that 60.1 ± 10.5% of glucose injected was disposed intracorporeally. The fraction of intracorporeal clearance and the fraction of intracorporeal glucose disposal were highly correlated (r = 0.94, p < 0.0001). The fraction of glucose disposed in hemodialysis patients can be determined from the amount of glucose injected and from the amount of glucose removed extracorporeally during hemodialysis without blood sampling. This measure could be of interest in surveillance of glucose control in hemodialysis patients.

Insulinogenic index in non-diabetics during haemodialysis

BACKGROUND The aim of this study was to analyse whether the insulin to glucose relationship following an intravenous glucose load in non-diabetic patients delivered during haemodialysis was affected by extracorporeal clearance and whether this relationship could be determined by an abridged sampling protocol. METHODS Studies were done during routine haemodialysis following the infusion of 0.5 g glucose per kilogram body mass. Extracorporeal effects were measured by online clearance (K(OCM)) and insulin clearance (K(I)). The insulin to glucose relationship was examined for a period of 1 h following the infusion of glucose. The integral response measured as the insulinogenic index (I(G)) was compared to the relationship between insulin and glucose concentrations measured for the whole period (k(IG)) as well as from only two samples taken at baseline and after 10 min (k(10)). RESULTS Eight non-diabetic haemodialysis patients (three females) with a dry body mass of 76.9 ± 18.2 kg completed the study. I(G) was 5.4 ± 4.4 U/mol and not different from normal reference values. A linear relationship providing characteristic slopes k(IG) was observed between arterial insulin and glucose levels. k(IG) was 6.1 ± 5.0 U/mol and not different from k(10) = 5.9 ± 4.8 U/mol measured after 10 min of glucose infusion and ongoing dialysis. I(G), k(IG) and k(10) were highly correlated (P < 0.0001), and k(10) showed substantial concordance (ρ(c) = 0.99) with I(G). Moreover, I(G), k(IG) and k(10) were independent of K(OCM) or K(I). CONCLUSIONS The insulin to glucose relationship is measurable within 10 min of glucose administration and unaffected by extracorporeal clearance. This could be helpful to characterize the insulin response to a glucose stimulus during haemodialysis.

Prevalence of Detectable Venous Pressure Drops Expected with Venous Needle Dislodgement

Venous needle dislodgement (VND) is a potentially fatal complication during hemodialysis (HD) treatment and the venous pressure monitor is the most widely used device for its detection. VND can only be detected by the venous sensor if the resulting pressure drop exceeds the difference between the actual venous pressure and the lower alarm limit. In clinical practice, the lower alarm limit is usually set 30–40 mmHg below the actual venous pressure to avoid a disproportionate high number of nuisance alarms.

Blunted insulinemia using high dialysate glucose concentration during hemodialysis.

The benefit of high glucose concentrations in the dialysate remains under debate. The aim of this study was to analyze and to compare the acute insulin response using a common but high glucose concentration in the dialysate representing a parenteral mode of glucose administration to oral glucose administration in stable and fasting nondiabetic hemodialysis patients during their routine hemodialysis session. Glucose was either given by a standardized oral load (75 g) or using a glucose concentration of 11.1 mmol/L (200 mg/dL) in the dialysate for the duration of an hour. The insulin response per unit glucose stimulus was determined from the slope of paired insulin and glucose concentrations measured in 15-minute intervals using standard techniques. This slope is mathematically equivalent to the insulinogenic index (IG) and has been shown to be independent of extracorporeal clearance by ongoing hemodialysis. In 10 subjects, the IG was 9.3 ± 2.6 U/mol with oral glucose delivery but only one-third of that value (3.0 ± 1.1 U/mol, p < 0.001) when glucose was delivered through the dialysate. Administration of glucose using dialysate thus leads to a blunted insulin response per unit glucose stimulus. This may cause prolonged hyperglycemia which should be avoided in patients treated with hemodialysis.

Response to active hepatitis B vaccination and mortality in incident dialysis patients

All patients with advanced chronic kidney disease or on renal replacement therapy should receive active hepatitis B vaccination. The aim of this retrospective cohort study was to investigate the association between the immune response to hepatitis B vaccination and all-cause, cardiovascular or infection-related mortality in incident dialysis patients starting dialysis between 2001 and 2008 (n=426) in two Austrian dialysis centers. Vaccination response was defined as follows: absent anti-HBs antibody titer or a titer <10IU/L was classified as non-response, seroconversion (SC) was defined as a titer ⩾10IU/L, and seroprotection (SP) as a titer ⩾100IU/L. Kaplan-Meier survival curves and multivariable adjusted Cox Proportional Hazards Models were used to determine the association between vaccination response and all-cause, cardiovascular and infection-related mortality. Of all patients 207 (48.6%) were non-responders, SC was observed in 219 (51.4%), SP in 118 (27.7%) patients. During a median follow-up of 51.2 months 228 (53.5%) patients died. Patients with SP and SC showed a significantly lower all-cause (p<0.001 for both) and cardiovascular mortality (p=0.006 for SP, p=0.01 for SC). SP and SC were independently associated with a significant risk reduction for all-cause mortality (SP: HR 0.69, 95% CI 0.49-0.97, p=0.03; SC: HR 0.72, 95% CI 0.55-0.95, p=0.02). In conclusion, achieving seroconversion and seroprotection after active hepatitis B vaccination is associated with significantly reduced all-cause mortality in incident dialysis patients. This simple and readily available tool allows estimation of patient survival independently of other well-known key parameters such as age, gender, the presence of diabetes and markers of malnutrition and inflammation.

Long-term outcome of en bloc pediatric kidney transplantation in adult recipients – up to 22 years of center experience

BACKGROUND Renal transplantation has been shown to be the best therapeutic option in end-stage renal disease patients. En bloc transplantation of pediatric kidneys into adult recipients (EBKT) is one strategy to increase the donor pool. We here report on 10 to 22 years of follow-up (median of 12.8 years) of patients receiving EBKT in a single-center, retrospective cohort study. MATERIAL AND METHODS The mean donor age was 14 ± 12 months and mean donor body weight was 8 ± 3 kilograms. Thirteen recipients (6 females, 7 males) were followed for 10 to 22 years. The mean recipient age was 44 ± 13 years at the time of transplantation. RESULTS Two of 13 patients lost their grafts in the first week because of hemorrhagic infarction of the kidney transplants or sepsis (septic shock). Only 1 patient had an acute cellular rejection, which was successfully treated with steroids and anti-CD3 antibody. Eleven out of 13 patients after EBKT survived and had a functioning graft 10 to 22 years after successful EBKT. The serum creatinine was 1.34 ± 0.6 mg/dl at 5 years (n=11), 1.37 ± 0.7 mg/dl at 10 years (n=11), 1.40 ± 0.6 mg/dl at 15 years (n=4), and 1.08 mg/dl at 20 years after EBKT (n=2). The eGFR, evaluated by using MDRD-2, was 66.5 ± 22 ml/min/m2 at 5 years (n=11), 62 ± 28 ml/min/m2 at 10 years (n=11), 56 ± 23 ml/min/m2 at 15 years (n=4), and 61 ml/min/m2 at 20 years after EBKT (n=2). Proteinuria did not increase significantly within the observation period. CONCLUSIONS In our experience, if the acute post-operative phase is uncomplicated, EBKT has excellent long-term graft and patient survival.

Osmotic and Hemodynamic Effects of Hypertonic Glucose During Hemodialysis

It was the purpose to quantify the hemodynamic effects of a bolus of hypertonic glucose injected into the extracorporeal system in a group of stable and nondiabetic patients during hemodialysis (HD). Glucose and electrolytes were measured in frequent intervals. Arterial blood pressures and heart rates were continuously recorded by noninvasive vascular unloading technique. Beat-to-beat stroke volume, cardiac output, and total peripheral resistance were determined by Modelflow method. Relative blood volumes were continuously measured by ultrasonic and optical means. Eight patients were studied in two treatments. Although arterial pressures and heart rates remained stable, stroke volume and cardiac output transiently increased above (19.2 ± 12.3%) and total peripheral resistance dropped below baseline (18.2 ± 8.6%) by a comparable magnitude. Relative blood volume transiently increased above baseline at 100% (104.9 ± 1.0%). Glucose concentrations were significantly related to relative blood volumes (r2 = 0.86, p < 0.001). In spite of a substantial increase in blood volume, a bolus of hypertonic glucose does not increase arterial pressures in nondiabetic patients because of concomitant vasodilatation. The relative increase in blood volume quantified by noninvasive HD technology follows the course of glucose and could be used as a surrogate to characterize patients with regard to their glucose metabolism during HD.

Intra- and Extracorporeal Clearance of Glucose Following an Intra-dialytic Glucose Load

There is increasing interest in glucose control during hemodialysis (HD) and related blood purification techniques. The aim of this study was to quantify the contribution of intra- and extracorporeal clearance to the decline of arterial glucose concentrations following the administration of a standardized glucose load during the regular HD treatment.