Serum Potassium and Acid-base Parameters in Severe Dialysis-associated Hyperglycemia Treated with Insulin Therapy

Abstract

We analyzed the changes in serum potassium concentration ([K]) and acid-base parameters in 43 episodes of dialysis-associated hyperglycemia (serum glucose level > 33.3 mmol/L), 22 of which were characterized as diabetic ketoacidosis (DKA) and the remaining 21 as nonketotic hyperglycemia (NKH). All episodes were treated with insulin therapy only. Age, gender, initial and final serum values of glucose, sodium, chloride, tonicity and osmolality did not differ between DKA and NKH. At presentation, serum values of [K] (DKA 6.2 ± 1.3 mmol/L; NKH 5.2 ± 1.5 mmol/L) and anion gap [AG] (DKA 27.2 ± 6.4 mEq/L; NKH 15.4 ± 3.5 mEq/L) were higher in DKA, whereas serum total carbon dioxide content [TCO2] (DKA 12.0 ± 4.6 mmol/L; NKH 22.5 ± 3.1 mmol/L), arterial blood pH (DKA 7.15 ± 0.09; NKH 7.43 ± 0.07) and arterial blood PaCO2 (DKA 26.2 ± 12.3 mm Hg; NKH 34.5 ± 6.7 mm Hg) were higher in NKH. At the end of insulin treatment, serum values of [K] (DKA 4.0 ± 0.7 mmol/L, NKH 4.0 ± 0.5 mmol/L), [AG] (DKA 16.3 ± 5.4 mEq/L, NKH 14.9 ± 3.0 mEq/L), [TCO2] (DKA 23.5 ± 5.0 mmol/L, NKH 24.1 ± 4.2 mmol/L), arterial blood pH (DKA 7.42 ± 0.09, NKH 7.51 ± 0.14) and arterial blood PaCO2 (DKA 31.8 ± 6.7 mm Hg, NKH 34.2 ± 8.3 mm Hg) did not differ between the two groups. Linear regression of the decrease in serum [K] value during treatment, (Δ[K]), on the presenting serum [K] concentration,([K]2), was: DKA, Δ[K] = 2.78 – 0.81 × [K]2, r = −0.85, p < 0.001; NKH, Δ[K] = 2.44 – 0.71 × [K]2, r = −0.90, p < 0.001. The slopes of the regressions were not significantly different. Stepwise logistic regression including both DKA and NKH cases identified the presenting serum [K] level and the change in serum [TCO2] value during treatment as the predictors of Δ[K] (R2 = 0.81). Hyperkalemia is a feature of severe hyperglycemia (DKA or NKH) occurring in patients on dialysis. Insulin administration brings about correction of DKA and return of serum [K] concentration to the normal range in the majority of the hyperglycemic episodes without the need for other measures. The initial serum [K] value and the change in serum [TCO2] level during treatment influence the decrease in serum [K] value during treatment of dialysis-associated hyperglycemia with insulin.

Abnormalities of serum potassium concentration in dialysis-associated hyperglycemia and their correction with insulin: review of published reports

“…in DH and compares them to representative reports of DKA and NKH occurring in patients with significant renal function. The main therapeutic difference between DH and hyperglycemia occurring in patients with preserved renal function is that insulin infusion is usually the only treatment needed to correct the fluid and solute abnormalities of DH [16][17][18]. The second purpose of this review was to analyze the published reports of the effects of insulin on serum K ?…”

“…Serum potassium concentration at presentation with hyperglycemia Table 1 shows serum levels of glucose, tonicity, TCO 2 , and K ? in published reports of dialysisassociated hyperglycemia (DH) [11,13,18,[20][21][22][23][24][25][26][27][28][29][30][31] containing a total of 471 cases. Tables 2 and 3 summarize 1,002 reported cases of diabetic ketoacidosis (DKA) [3,[32][33][34][35][36][37][38][39][40][41][42] and 1,048 published cases of nonketotic hyperglycemia (NKH) [5,37,[39][40][41][42][43][44][45][46][47][48][49][50], respectively, in patients with preserved renal function.…”

“…is not sufficient to establish dialysis-associated hyperglycemia (DH) as a risk factor for hyperkalemia. Figure 2 compares frequencies of hyperkalemia in studies of DH [18,31] and in studies analyzing all serum samples of diabetic patients on dialysis [30,51]. Hyperkalemia was more frequent in DH.…”

“…The [30,51]. Back row: Only blood samples with dialysis-associated hyperglycemia [18,31]. The frequency of hyperglycemia (both serum K ?…”

“…The finding that the rise in serum TCO 2 was a predictor of the decrease in serum K ? during correction of DH [18,30] could be related to the correction of DKA.…”