title: Cardiac arrhythmias and electrolyte changes during haemodialysis.
abstract: Cardiac arrhythmias are a frequent event in chronic haemodialysis patients, and their pathogenesis is still poorly understood. We evaluated plasma K+ (PK), intraerythrocytic K+ (EK) and acid-base changes during haemodialysis in six patients with frequent arrhythmias (A-pts), and in six (used as controls) nonarrhythmic dialysis patients (C-pts). PK decreased significantly (P less than 0.01) during haemodialysis in both groups: A-pts (pre HD: 4.81 +/- 0.52 mM; 1st hour: 3.66 +/- 0.44; end HD: 3.17 +/- 0.38) and C-pts (4.75 +/- 0.80; 3.71 +/- 0.32 and 3.18 +/- 0.18 respectively) without any significant difference at any time between the two groups. Predialysis arterial pH and HCO3 were similar in A-pts (7.33 +/- 0.07 and 22.1 +/- 4.5 mM) and C-pts (7.29 +/- 0.04 and 19.7 +/- 2.6 mM) but an apparently better correction of acidosis within the treatment was seen in A-pts (arterial pH 1st hour: 7.38 +/- 0.07; end HD: 7.39 +/- 0.07) than C-pts (1st hour: 7.31 +/- 0.02, P less than 0.05 versus A-pts; end HD: 7.33 +/- 0.03, P less than 0.05 versus A-pts). EK was significantly (P less than 0.01) greater at all times in C-pts (pre HD: 90.6 +/- 15.7 mmol/l RBC; 1st hour: 93.3 +/- 11.7; end HD 96.6 +/- 10.7) than A-pts (72.1 +/- 9.0; 77.2 +/- 3.7 and 79.3 +/- 8.4, respectively). We conclude that haemodialysis patients with arrhythmias have a decreased intraerythrocytic K content in comparison with other patients despite similar PK values; this finding might constitute a predisposing factor for arrhythmias.
authors.affiliation: Divisione di Nefrologia e Dialisi, Ospedale Niguarda-Ca'Granda, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Rombolà
authors.forename: G
authors.initials: G
authors.lastname: Colussi
authors.forename: M E
authors.initials: ME
authors.lastname: De Ferrari
authors.forename: A
authors.initials: A
authors.lastname: Frontini
authors.forename: L
authors.initials: L
authors.lastname: Minetti
mesh_terms: D000136:Acid-Base Equilibrium; D001145:Arrhythmias, Cardiac / Q000097:blood / Q000209:etiology*; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood*; D011191:Potassium Deficiency / Q000150:complications; D006435:Renal Dialysis / Q000009:adverse effects*
chemical_list: D011188:Potassium