title: Differences in heart rate variability during haemodialysis and haemofiltration.
abstract: BACKGROUND
  The aim of our study was to evaluate whether convective (haemofiltration, Hf) and diffusive (haemodialysis, Hd) dialysis techniques induce different patterns of long- and short-term autonomic adjustments in haemodynamically stable dialysis patients.
  
  
  METHODS
  Ten haemodynamically stable Hd patients were studied. Each patient underwent a block of six Hd sessions, then was switched to six Hf. During the last session of each dialytic treatment, continuous beat to beat measurements of systolic arterial pressure (SAP) and heart rate (HR) were performed. Spectral analysis of heart rate variability (HRV) was made before and during the treatment to evaluate the modification of autonomic nervous system activity.
  
  
  RESULTS
  Baseline values of plasma sodium, body weight, HR and SAP were not different for the two considered methods of dialysis, while the baseline values of normalized LF were significantly higher in Hf as compared to Hd and the opposite was observed for HF powers (P < 0.001). Sodium balance and body weight loss per hour did not differ between Hd and Hf while body temperature was kept constant in all sessions. Throughout the dialytic procedures, with both techniques, SAP was constant, while HR diminished from the first hour till the end of the procedure (P < 0.05). An increase in LF (and decrease in HF) was noticed only in the case of Hd, considering normalized units (P < 0.05). These selective changes were maintained also during the recovery after the procedure.
  
  
  CONCLUSIONS
  The spectral analysis of RR interval variability during Hd and Hf suggests a potential autonomic advantage with Hf, to be added to the well-recognized intrinsic greater haemodynamic stability.
authors.affiliation: Clinica Nefrologica - Università degli studi di Milano Bicocca-Ospedale S Gerardo, Milan, Italy. simonetta.genovesi@unimib.it
authors.forename: Simonetta
authors.initials: S
authors.lastname: Genovesi
authors.forename: Oscar
authors.initials: O
authors.lastname: Bracchi
authors.forename: Paolo
authors.initials: P
authors.lastname: Fabbrini
authors.forename: Elena
authors.initials: E
authors.lastname: Luisetto
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Viganò
authors.forename: Daniela
authors.initials: D
authors.lastname: Lucini
authors.forename: Mara
authors.initials: M
authors.lastname: Malacarne
authors.forename: Andrea
authors.initials: A
authors.lastname: Stella
authors.forename: Massimo
authors.initials: M
authors.lastname: Pagani
mesh_terms: D000368:Aged; D001835:Body Weight; D004058:Diffusion; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006440:Hemofiltration / Q000379:methods*; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D009991:Oscillometry; D006435:Renal Dialysis / Q000379:methods*; D012964:Sodium / Q000097:blood / Q000378:metabolism; D013599:Systole
chemical_list: D012964:Sodium