Effect of a plasma sodium biofeedback system applied to HFR on the intradialytic cardiovascular stability. Results from a randomized controlled study

Abstract

BackgroundIntradialytic hypotension (IDH) is still a major clinical problem for haemodialysis (HD) patients. Haemodiafiltration (HDF) has been shown to be able to reduce the incidence of IDH.MethodsFifty patients were enrolled in a prospective, randomized, crossover international study focussed on a variant of traditional HDF, haemofiltration with endogenous reinfusion (HFR). After a 1-month run-in period on HFR, the patients were randomized to two treatments of 2 months duration: HFR (Period A) or HFR-Aequilibrium (Period B), followed by a 1-month HFR wash-out period and then switched to the other treatment. HFR-Aequilibrium (HFR-Aeq) is an evolution of the haemofiltration with endogenous reinfusion (HFR) dialysis therapy, with dialysate sodium concentration and ultrafiltration rate profiles elaborated by an automated procedure. The primary end point was the frequency of IDH.ResultsSymptomatic hypotension episodes were significantly lower on HFR-Aeq versus HFR (23 ± 3 versus 31 ± 4% of sessions, respectively, P l= l0.03), as was the per cent of clinical interventions (17 ± 3% of sessions with almost one intervention on HFR-Aeq versus 22 ± 2% on HFR, P <0.01). In a post-hoc analysis, the effect of HFR-Aeq was greater on more unstable patients (35 ± 3% of sessions with hypotension on HFR-Aeq versus 71 ± 3% on HFR, P <0.001). No clinical or biochemical signs of Na/water overload were registered during the treatment with HFR-Aeq.ConclusionsHFR-Aeq, a profiled dialysis supported by the Natrium sensor for the pre-dialysis Na+ measure, can significantly reduce the burden of IDH. This could have an important impact in every day dialysis practice.

Characterising Haemodynamic Stress during Haemodialysis Using the Extrema Points Analysis Model

“…Although IDH and postural drop after dialysis were found to be independent risk factors for 2-year mortality in HD patients [7], the link between IDH on the one hand and functional and structural end-organ abnormalities on the other is not substantiated. Furthermore, there is no universal definition of IDH, and different studies used different definitions [8,9,10]. …”

Sodium Prescription in the Prevention of Intradialytic Hypotension: New Insights into an Old Concept

“…The difference observed between the mean sodium values obtained by Natrium at dialysis end and the values of the sodium target is 1.0 mEq/L [39]. An equation ([Na + ] = 13.95* C uf - 53.48) is currently used to correlate endogenous ultrafiltrate conductivity and plasma sodium [40]. In turn, the correlation equation calculates the plasma sodium to be given in real time to the mathematical model [40], which then recalculates the patient's predialysis sodium profile by considering the value at 15 min and at 60 min from dialysis start (Fig.…”

“…Intradialytic hypotension was defined according to Colì et al [35]: (i) an SBP value ≤90 mm Hg in patients with a predialysis SBP value >100 mm Hg, even if not accompanied by symptoms and therapeutic interventions; (ii) any SBP reduction ≥25 mm Hg compared to the predialysis value in the presence of symptoms and therapeutic maneuvers; (iii) an SBP reduction of at least 10% accompanied by typical symptoms (nausea, vomiting, headache, dizziness) in patients with a predialysis SBP value <90 mm Hg. The results showed the following indications: (a) a significant reduction of dialysis sessions complicated by hypotension using HFR-Aeq; (b) a significant reduction of symptomatic hypotension cases (23 ± 3% in HFR-Aeq vs. 31 ± 4% in HFR, p = 0.03); (c) a reduced onset of intradialytic morbid events requiring nursing interventions (17 ± 3% of sessions with at least one intervention in HFR-Aeq vs. 22 ± 1% of sessions with at least one intervention in HFR, p < 0.01) [40]. SBP significantly increased in HFR-Aeq 60 min after the start of dialysis with respect to values measured in HFR, whereas DBP values rose significantly in the second half of the dialysis session with HFR-Aeq compared to HFR.…”

“…SBP significantly increased in HFR-Aeq 60 min after the start of dialysis with respect to values measured in HFR, whereas DBP values rose significantly in the second half of the dialysis session with HFR-Aeq compared to HFR. Dividing patients into quartiles according to the percentage of dialysis sessions complicated by hypotension, a significant reduction in the number of hypotension events was found in patients presenting arterial hypotension in more than 75% of dialysis sessions [40]. In addition, HFR-Aeq treatment maintained hemodynamic stability during dialysis with preservation of patients' sodium balance: no differences were found between HFR and HFR-Aeq serum sodium concentrations predialysis (138.6 ± 0.5 vs. 139.4 ± 0.5 mEq/L) and post-dialysis (139.2 ± 0.2 vs. 139.7 ± 0.52 mEq/L).…”

“…In addition, HFR-Aeq treatment maintained hemodynamic stability during dialysis with preservation of patients' sodium balance: no differences were found between HFR and HFR-Aeq serum sodium concentrations predialysis (138.6 ± 0.5 vs. 139.4 ± 0.5 mEq/L) and post-dialysis (139.2 ± 0.2 vs. 139.7 ± 0.52 mEq/L). End-dialysis serum sodium in HFR-Aeq was equal to the sodium target (139.7 ± 0.2 vs. 139.0 ± 0.1 mEq/L) [40]. Nonetheless, Locatelli et al [40] considered 13 chronic HD patients with diabetes out of 50 (26%); they were on strict anti-diabetic therapy.…”