Prevalencia de pseudohipercaliemia en pacientes con enfermedad renal crónica en terapia hemodialítica / Prevalence of pseudohyperkalemia in patients with chronic renal disease in hemodialysis therapy

Objetivo: determinar si a la hipercaliemia prolongada en pacientes en hemodiálisis con enfermedad renal crónica (ERC) contribuye en valor significativo la presencia de pseudohipercaliemia (diferencia entre potasio sérico a plasmático mayor a 0.5 mEq/L) Pacientes: aquellos con ERC en terapia hemodialítica por más de 12 meses de evolución en quienes se detectara hipercaliemia persistente por más de tres meses. Material y métodos: determinación simultánea de potasio sérico y plasmático, y adicionalmente las variables sodio sérico, gases arteriales, cuadro hemático completo, glucemia en ayunas, Kt/v y electrocardiograma Resultados: en 110 pacientes evaluados 17 cumplieron los criterios de inclusión, en ellos en 13 (76.47%) se detectó pseudohipercaliemia y en 4 (23.52%) hipercaliemia verdadera (diferencia entre potasio sérico a plasmático menor a 0.5 mEq/L). No se detectaron diferencias significativas entre grupos en las variables analizadas Conclusión: la pseudohipercaliemia representa un porcentaje muy importante del reporte de hipercaliemias en pacientes con ERC en terapia hemodialítica, y lo ideal en ellos es siempre determinar potasio plasmático. (Acta Med Colomb 2013; 38: 12-15).

Objective: determine if to prolonged hyperkalemia in hemodialysis patients with chronic kidney disease (CKD) contributes significantly the presence of pseudohyperkalemia (difference between serum to plasma potassium greater than 0.5 mEq/L) Patients: those with CKD on hemodialysis therapy for more than 12 months duration in whom persistent hyperkalemia is detected for more than three months. Materials and methods: simultaneous determination of serum and plasma potassium and in addition the variables serum sodium, arterial blood gases, complete blood count, fasting blood glucose, Kt / v and electrocardiogram Results: in 110 patients evaluated 17 met the inclusion criteria. In 13 of them (76.47%) we detected pseudohyperkalemia and in 4 (23.52%) true hyperkalemia (difference between serum to plasma potasium less than 0.5 mEq / L ). No significant differences between groups in the variables analyzed were detected. Conclusion: the pseudohyperkalemia represents a very important percentage of the report of hiperkalemias in CKD patients on hemodialysis therapy, and ideally plasma potasium has to be determined always in these patients. (Acta Med Colomb 2013; 38: 12-15).

Levels of plasma sodium and potassium as well as alterations in adrenal cortex of Rattus norvegicus in response to sublethal heroin administration.

In order to record the effects of sublethal heroin administration on plasma mineral metabolism, the drug was administered intramuscularly (16.4 mg kg-1 body weight day-1; 0.75 LD50 dose) in Rattus norvegicus for 30 days. Plasma sodium and potassium levels of the control rats fluctuated between 153.14 ± 2.88-157.23 ± 2.16 meq l-1 and 5.04 ± 0.32-5.63 ± 0.41 meq l-1, respectively. Plasma sodium level of the treated rats registered a progressive decline (p<0.01) at 24 hr with the minimum value (126.53 ± 2.68 meq l-1) on day 30 whereas plasma potassium level registered a progressive increase during entire period of the treatment with peak (8.78 ± 0.23 meq l-1) on day 30. Though sublethal herion adminstration for 30 days elcited cytoplasmic vacuolation in all the three zones of adrenal cortex, much of cytological alterations were observed in zona glomerulosa and zona fasciculata cells. In zona glomerulosa cells, degenerative changes in the organelles were more pronounced as evident by the loss of typical cristae in the mitochondria and hormone granules were rarely seen in these cells. Though rough endoplasmic reticula were scanty, many lipid granules encountered in zona glomerulosa cells of the treated rats.

The Significance of Plasma Potassium Level in Pseudohyperkalemia with Thrombocytosis / 대한소아혈액종양학회지

PURPOSE: As blood coagulates, potassium is released from cells, causing the concentration of potassium in serum to be slightly higher than that of plasma. We measured serum and plasma potassium levels simultaneously to evaluate the significance of plasma potassium especially in the patients with thrombocytosis. METHODS: The study was designed into two steps. To determine the relationship between platelet count and serum potassium level, the subjects of the first study were 140 children admitted to the National Medical Center (NMC) from January 1996 to June 1997. To determine the significance of plasma potassium level in pseudohyperkalemia with thrombocytosis, the subjects of the second study were 80 children admitted to the NMC from June 1997 to June to 1998. All of them are 1 month to 14 years old. RESULTS: 1) There was no relationship between the platelet count and serum potassium levels in the control group with platelet count from 150x109/L to 400x10(9)/L (r=0.07), but there was significant relationship in the group with platelet count above 400x10(9)/L (r=0.41, P<0.01). 2) As platelet counts increased, the differences between the serum and plasma potassium concentration increased (r=0.518, P<0.01). CONCLUSION: The clinician should pay attention to the possibility of the pseudohyperk alemia when there is thrombocytosis with hyperkalemia without specific hyperkalemic symptoms or EKG changes. Plasma potassium level will be helpful for the accurate assesment of potassium concentration.

Comparison of Changes in Plasma Potassium Levels Induced by Brachial Plexus Block with Admixture of Clonidine or Epinephrine to 0.5 % Bupivacaine / 대한마취과학회지

The addition of epinephrine to local anesthetics for peipheral nerve blocks reduces the risk of local anesthetic toxicity by delaying systemic absorption and prolongs block duration. But there is general agreement that epinephrine causes a decrease in plama K+ in humans that can be associated with a variety of cardiac dysrhythmias. Clonidine, a selective 2 adrenergic agonist, has been reported to increase the local anesthetic effect. And the addition of clonidine to local anesthetics in peripheral nerve block prolongs block duration and postoperative analgesia. The admixture of clonidine or epinephrine to bupivacaine for brachial plexus block was studied with regard to plasma potassium concentrations and hemodynsmie changes. Thirty-three patients of ASA physical statue I and II received an admixture of clonidine (150g; n=11), epinephrine (200g; n=11), or normal saline (placebo; n=11) to 30 ml of 0.5% bupivacaine in a randomized, double blind fashion. There were no differences in arterial blood pressure and heart rate among the three groups. In patients who had received epinephrine admixture, decrease of plasma potassium at 15min after block was significant compared with patients who had received clonidine. Clonidine may be a useful adjunt to loeal anesthetics in those patients in whom the administration of epinephrine is contraindicated.