Incidence, risk factors, and recognition of pseudohyperkalemia in patients with chronic lymphocytic leukemia.

Pseudohyperkalemia, a false elevation of potassium level in vitro, can be observed in chronic lymphocytic leukemia (CLL) patients due to fragility of leukocytes along with a high leukocyte count. This retrospective, observational study included all patients diagnosed with CLL at our hospital who had at least one leukocyte count ≥ 50.0 × 109/L during the years 2008-2018. All hyperkalemic episodes (including when leukocyte count was below 50.0 × 109/L) during this period were assessed. Pseudohyperkalemia was defined as when a normal potassium level was measured in a repeated blood test or when known risk factors and ECG changes typical of hyperkalemia were absent. Of the 119 episodes of hyperkalemia observed, 41.2% were considered as pseudohyperkalemia. Pseudohyperkalemia episodes were characterized by significantly higher leukocyte counts as well as higher potassium and LDH levels compared to true hyperkalemia. Pseudohyperkalemia was documented in medical charts only in a minority of cases (n = 4, 8.1%). Treatment was administered in 17 of 49 (34.7%) cases and caused significant hypokalemia in 6 of those cases. The incidence of pseudohyperkalemia in this study was rather high, suggesting that physicians should be more aware of this phenomenon in patients with CLL.

Renal impairment, hypertension and plasma urotensin II.

BACKGROUND: Human urotensin II (UII) is a potent mammalian vasoconstrictor thought to be produced and cleared by the kidneys. Conflicting data exist regarding the relationship between UII concentrations, kidney function and blood pressure (BP). We measured the associations between kidney function [including end-stage renal disease (ESRD)] and levels of BP with plasma concentrations of UII. METHODS: Ninety-one subjects were enrolled. Thirty-one subjects had ESRD (undergoing haemodialysis), 30 subjects had chronic kidney disease (CKD) and 30 control subjects had no kidney disease. Plasma UII concentrations were measured by radioimmunoassay. RESULTS: Mean plasma UII concentrations were highest in controls, lower in subjects with ESRD and lowest in subjects with non-ESRD CKD (P<0.0001). UII concentrations correlated negatively with serum creatinine (P=0.0012) and CKD stage, and positively with creatinine clearance (P=0.013). In ESRD subjects, plasma UII (P=0.008) increased after dialysis, while SBP (P=0.007), DBP (P=0.009), serum creatinine (P<0.0001) and serum urea nitrogen (P<0.0001) decreased. UII concentrations were lower in patients with a history of hypertension (HTN) (P=0.016). Age, race and gender did not appear to be associated with UII concentration. However, the distribution of African American race and male gender appear to be associated with increasing stages of chronic kidney disease. CONCLUSIONS: These data suggest a potential vasodilatory role of UII in humans with kidney disease or hypertension. The reduction in UII levels in CKD also suggests either reduced production or greater clearance, or both, of UII.

The pharmacokinetics and cardiovascular effects of high-dose articaine with 1:100,000 and 1:200,000 epinephrine.

OBJECTIVES: The authors conducted a randomized, double-blind, two-way crossover clinical trial to compare the pharmacokinetics and cardiovascular effects of 11.9 milliliters of 4 percent articaine hydrochloride (HCl) plus 1:100,000 epinephrine (A100) with those of 11.9 mL of 4 percent articaine HCl plus 1:200,000 epinephrine (A200). METHODS: During two testing sessions, the authors administered injections of A100 and A200 over a seven-minute period (in one-cartridge doses unless otherwise noted): maxillary right first molar infiltration, maxillary left first molar infiltration, maxillary right first premolar infiltration, maxillary left first premolar infiltration, right inferior alveolar injection, left inferior alveolar injection, right long buccal infiltration (one-half cartridge) and left long buccal infiltration (one-half cartridge). They analyzed venous blood samples for articaine levels. They used noninvasive acoustic tonometry to measure a variety of cardiovascular parameters over a two-hour period. RESULTS: Plasma concentration curves of articaine over time were similar for both solutions, with peak concentrations and times to maximum concentration being 2,037 nanograms per milliliter and 22 minutes for A100 and 2,145 ng/mL and 22 minutes for A200. At the 10-minute point, the mean systolic blood pressure and heart rate were significantly elevated (P < .05) with A100 versus A200. CONCLUSIONS: Maximum dose recommendations for the A100 solution also can be applied to the A200 solution. A200 produces less cardiovascular stimulation than does A100. CLINICAL IMPLICATIONS: A200 is as safe as A100, and may be preferable to A100 in patients with cardiovascular disease and in those taking drugs that reportedly enhance the systemic effects of epinephrine.

When chronic kidney disease becomes advanced. Guidelines for care in the emergency department and hospital.

Patients with advanced chronic kidney disease or end-stage renal disease live with a serious condition that often necessitates visits to an emergency department and subsequent hospitalization. Often, physicians in these settings are not trained in nephrology. Emergency department physicians and other nonnephrologists who regularly manage advanced chronic kidney disease and end-stage renal disease need to follow several basic principles to provide excellent care to patients with these conditions.

Mechanisms of hypertension associated with BAY 43-9006.

PURPOSE: BAY 43-9006 (sorafenib) is an inhibitor of Raf kinase, the vascular endothelial growth factor (VEGF) receptor-2, and angiogenesis in tumor xenografts. The current study investigated the incidence, severity, and mechanism of blood pressure (BP) elevation in patients treated with BAY 43-9006. PATIENTS AND METHODS: Twenty patients received BAY 43-9006 400 mg orally twice daily. BP and heart rate were measured at baseline and then every 3 weeks for 18 weeks. VEGF, catecholamines, endothelin I, urotensin II, renin, and aldosterone were measured at baseline and after 3 weeks of therapy. We assessed vascular stiffness at baseline, after 3 to 6 weeks of therapy, and again after 9 to 10 months of therapy. RESULTS: Fifteen (75%) of 20 patients experienced an increase of > or = 10 mmHg in systolic BP (SBP), and 12 (60%) of 20 patients experienced an increase of > or = 20 mmHg in SBP compared with their baseline value, with a mean change of 20.6 mmHg (P < .0001) after 3 weeks of therapy. There were no statistically significant changes in humoral factors, although there was a statistically significant inverse relationship between decreases in catecholamines and increases in SBP, suggesting a secondary response to BP elevation. Measures of vascular stiffness increased significantly during the period of observation. CONCLUSION: Treatment with BAY 43-9006 is associated with a significant and sustained increase in BP. The lack of significant change in circulating factors suggests that these humoral factors had little role in the increase in BP.

Pharmacologic adjuvants to epoetin in the treatment of anemia in patients on hemodialysis.

Anemia is a common complication of chronic kidney disease, particularly in patients who are on dialysis. The use of recombinant human erythropoietin has led to the eradication of severe anemia in the dialysis population. Correction of anemia in these patients has been associated with better quality of life and clinical outcomes. Some hemodialysis patients have anemia that either is relatively refractory to epoetin therapy or requires very high doses of epoetin (i.e., hyporesponsiveness), despite having adequate iron stores, and are thus unable to achieve or maintain target hemoglobin levels. Several pharmacologic agents have been studied for effects on improving response to epoetin, either to counter hyporesponsiveness or simply to reduce epoetin use for purely economic reasons. This review examines the available literature regarding the efficacy of these potential pharmacologic adjuvants to epoetin in the treatment of anemia in patients on maintenance hemodialysis, with special emphasis on androgens, vitamin C (ascorbic acid), and L-carnitine. A review of published guidelines and recommendations for use of these agents in hemodialysis patients is provided.

Use of low molecular weight heparins and glycoprotein IIb/IIIa inhibitors in patients with chronic kidney disease.

Despite aggressive intervention, cardiac causes of death, including acute coronary syndrome (ACS), continue to be a major source of mortality in patients with chronic kidney disease (CKD), including end-stage renal disease (ESRD). Multiple large prospective trials have demonstrated the clinical benefits of both low molecular weight heparin (LMWH) and glycoprotein (Gp) IIb/IIIa inhibitors in treating patients with ACS. Unfortunately patients with significant impairment of kidney function have generally been excluded from these major clinical trials. Consequently relatively little is known about the pharmacokinetics, appropriate dosing, efficacy, and safety of these medications in patients with CKD of various stages. This article examines the available literature regarding the pharmacokinetics, dosing, efficacy, and safety of LMWH and Gp IIb/IIIa inhibitors in patients with CKD.

Religiosity in a hemodialysis population and its relationship to satisfaction with medical care, satisfaction with life, and adherence.

BACKGROUND: The religious beliefs and spirituality of patients on hemodialysis (HD) therapy have not been studied extensively. Studies of the dialysis population seem to indicate that religion may be associated with increased patient satisfaction with life and increased levels of social support. METHODS: Using multiple religiosity scales and scales to assess patient satisfaction with life and social support, we studied the relationship between religiosity and medical and/or social factors and adherence to treatment in 74 HD patients. RESULTS: High scores on the Intrinsic Religiosity Scale were associated strongly with high scores on the Satisfaction With Life Scale, whereas age and high Organizational Religious Activity Scale scores were associated strongly with high scores on the Satisfaction With Medical Care Scale. Older age was associated strongly with increased adherence. No relationship existed between religiosity and adherence in our population. CONCLUSION: Religious beliefs are related strongly to measures of satisfaction with life, whereas religious behaviors are related to satisfaction with medical care. Age is the single most important demographic factor associated with adherence. Because of the complex nature of religiosity, additional investigation is in order.