Dyskalemia Dyscalcemia Hafid Ait-Oufella, MD.PhD. Medical Intensive Unit Care Saint-Antoine Hospital, Paris
Potassium K + Molecular weight: 39 1gr K + =2.5mmol
Potassium disorders in ICU : Our experience Jul 1997 Dec 1998 893 patients Kalemia < 2,5 mmol/l, n = 1 Kaliemia > 6,5 mmol/l, n = 15 Kaliemia > 7 mmol/l, n = 10
Potassium: balance & distribution Western Diet: 100mEq K + K + Stool: 10 meq Urine: 90 meq
Distribution of Potassium Extracellular fluid Intracellular fluid K + = 3.5-5 meq/l K + = 140-150 meq/l 350 meq (10%) 3150 meq (90%) Plasma (0.4%) Interstitium (1%) Bone (8.6%) Muscle (75%) Liver (7%) Red cells (7%)
Potassium: balance & distribution Western Diet: 100mEq K + K + Stool: 10 meq Urine: 90 meq
Na+ Insulin 2K+ ATPase H+ Na+ 3Na+ ATPase 2K+ ß2 agonists
Distal convolted tubule Glomerulus Proximal convolted tubule Henle s loop Aldosterone Na 2+ K+
Hyperkalemia
Mechanisms of hyperkalemia Increase intake Oral (?) Perfusion Cellular Lysis Tumor lysis ExtraC transfer Acidosis Insulinopenia ß-adrenergic blockade K+ K+ Rabdomyolysis Hemolysis Catabolic state Digitalis intoxication Stool Urine Decreased renal excretion Renal failure K+ sparing diuretics NSAI drugs ACE inhibitors Mineralocorticoids deficiency
Hyperkalemia >6.5mmol/L our experience (5 years) N = 50 (1,1 %) Uree 28,8 + 22,1 mmol/l Drugs, n = 29 (58 %) ACE inhibitors (n = 10) K sparing diuretics (n = 10) Potassium per os (n = 8) Heparin (n = 7) NSAI drugs (n = 6) Betablockers (n = 6) Drugs association n=1 (13pts ); n=2 (10pts) ; n=3 (5pts) ; n=4 (1pt) Co-morbidity : Chronic renal failure n = 10, Diabetes n = 8 Age > 60 ans n=35 Age > 80 ans n=19
Messages Hyperkalemia frequently occurs in old patients with diabetes that have combination of nephrotoxic drugs. Life-threatening hyperkalemia is (almost) always associated with renal failure
-120 Hyperpolarisation 37 C -100 THIN QRS fin QRS Silent Potentially lethal Induces cardiac arythmia Potentiel de membrane (mv) Membrane potential 0-20 -40-60 -80 LARGE QRS QRS large Em=Tx1,7x Log10 (Ke/Ki) Dépolarisation Kaliémie (mmol/l) 0 5 10 15 Hyperkalemia
Hyperkalemia & cardiac arythmia ECG modifications and cardiac arythmia depend on : Potassium level Time over which hyperkaliemia develops Co-morbidities Others electrolytic disorders Drugs (Digitalis) Genetic susceptibility No threshold for arythmia!
Mr A.., 27-year-old, chronic hemodialysis, feeling of faintness K: 7,1 mmol/l HCO3: 27 mmol/l After dialysis K: 4,5 mmol/l Day1 K: 5,2 mmol/l
Message Hyperkalemia = Electrocardiogramm Modification QRS widening No ECG modification Emergency Caution
Hyperkaliemia: treatment (1) ECG modifications: Calcium chloride (5ml of 10% solution) or calcium gluconate (10mL of 10% solution) K: 9,6 mmol/l Ph: 7,08 HCO3: 13 mmol/l 20mL calcium gluconate (10%) After dialysis K + : 3.1mmol/L
Hyperkalemia: treatment (2) Shift K+ into cells : 20-30 minutes Product Doses Caution Glucose/ insulin Rapid Insulin Dextrose 10% 100ml Dextrose 10% glycemia 10UI Insulin Alkalinization Sodium bicarbonate 84 100ml Pulmonary overload ß2 adrenergic agonists Salbutamol Nebulization 1mg Sodium polystyrene sulfonate Binding resins: 1-2 hours kayexalate 50-100g every 4 hours Gut obstruction Threatening hyperkalemia
Hyperkalemia: treatment (3) Medical managment of hyperkalemia is the first step with ECG monitoring Dialysis is the definitive treatment Dialysis could be delayed or avoided if diuresis restarts
Hypokalemia
Mechanisms of hypokalemia Vomiting nasogastric drainage IntraC transfer Alkalosis Insulin ß-adrenergic agonists K+ K+ Theophyllin Intestinal losses Diarrhea Laxative abuse Stool Urine Increased renal excretion
Renal loss of potassium Potassium concentration in urines is high Normal blood pressure : Diuretics hypomagnesaemia Renal tubular acidosis Genetic defect (Bartter s syndrom, Gitelman s syndrom) High blood pressure Increased aldosterone : Primary (low renin) Secondary (high renin)
N = 22 Hypokalemia <2mmol/L our experience (5 years) Kalemia: 1,8 + 0,3 mmol/l No death Psychiatric disease et/ou denutrition, n = 11 (50 %) Diarrhea and/or vomiting, n = 18 (82 %) ph : 7,56 + 0,11 HCO3- : 40,3 + 15,7 mmol/l Drugs n = 7 Diuretics n = 7 Laxative n = 4 Beta 2 agonists n = 1
Clinical manifestations of hypokalemia Electrocardiogramm modifications and arythmia! Neuromuscular - Constipation/ileus - Weakness/cramps - Myalgies/ Rabdomyolysis - Paralysis
Hypokalemia : electrocardiogramm U wave U wave > T wave U/T wave fusion Sagging of ST segment Flattening of T wave QRS widening
Message : Do not treat numbers! K=1.5mmol/l
Treatment of hypokalemia ECG modification Intravenous potassium supplementation Infusion<1.5g/h Treating the underlying condition Magnesium supplementation
Magnesium depletion is frequently associated with hypokalemia Whang, Arch Int Med 1985
Treatment of hypokalemia Treating the underlying condition ECG modification No ECG modification Intravenous potassium supplementation No emergency Potassium supplementation Infusion<1.5g/h Magnesium supplementation
K supplementation
Conclusion Dyskalemia is not exceptional Dyskalemia could induce lethal cardiac arythmia Do not treat numbers! Management of dyskalemia depends on ECG modification
Hypercalcemia Admission in ICU for hypercalcemia is now exceptional since biphophonates use
Hypercalcemia : definition ionized Protein phosphate/citrate Elevated calcium level in the blood >105mg/l (2.6mmol/l) Adjusted Ca = Ca measured + [(40-albumin) X 0.025] Ionized Calcium level in the blood >53mg/l (1.3mmol/l)
Calcium metabolism Calcium : 1Kg 99% bone
Calcium metabolism
Hypercalcemia - Malignancy Multiple myeloma Metastasis (breast, lung, thyroid,kidney) - Hyperparathyroidism Malignancy and hyperparathyroidism represent 90% of hypercalcemia causes - Others : Vitamin D disorders (Vitamin D intoxication, sarcoidosis ) Chronic renal failure High bone turn over (hyperthyroidism, Paget s disease )
Clinical manifestations of hypercalcemia Symptoms of hypercalcemia are NOT SPECIFIC, depend on the underlying cause of the disease, the time over which it develops and the overall physical health of the patient. Nausea, vomiting,constipation, abdominal pain Polyuria-polydipsia Weakness Alteration of mental status, confusion, coma ECG : tachycardia, shortening of QT interval and risk of cardiac arythmia (digitalis treatment)
Treatment of hypercalcemia Treatment of the underlying disease Hydratation Hypokalemia correction Name Action time Indications Mechanisms Biphosphonates Calcitonin Corticosteroids Gallium nitrate Pamidronate Etidronate Clodronate Cibacalcin Methyl prednisolone Ganite 24-48 hours 6-12 hours Few days Few days Reference Emergency Metastasis, myeloma, sarcoidosis Inhibition of bone resorption Inhibition of bone reabsorption and increase renal excretion Increase urinary excretion decrease intestinal absorption Inhibition of bone resorption
Hypocalcemia Hypocalcemia is not a problem in ICU Calcium level in the blood <90mg/l (2.1mmol/l) Ionized Calcium level in the blood <45mg/l (1.1mmol/l) Mechanisms of hypocalcemia - Hypoparathyroidism - Peripheral resistance to parathormon Clinical manifestations are not specific - Perioral tigling, parasthesia, tetany, carpopedal spasm - Trousseau s sign Chvosteck s sign Treatment : calcium gluconate 10%, 20ml if hypocalcemia is severe
Conclusion Dyskalemia could induce lethal cardiac arythmia ECG analysis has a crucial role to manage dyskalemia Life-threatening hypercalcemia is now exceptional since biphophonates use
Question 1 Was is the first think(s) to do in front of hyperkalemia? A) Injection of calcium gluconate B) Electrocardiogramm C) Measure calcemia D) Analyze patient s medications E) Dialysis
Question 2 The risk of cardiac arythmia induced by hyperkalemia depends on : A) Potassium level B) Time of hyperkalemia development C) Overall physical health D) Associated dyscalcemia E) Doesn t exist when kalemia <6.5mmol/l
Question 3 About hypokalemia: A) Hypokalemia is the most frequent electrolytic disorder in ICU B) ECG has to been done only if K + <2mmol/l C) Hypermagnesemia is frequently associated with hypokalemia D) Hypokalemia could induce torsade E) Intravenous potassium replacement is required if K + <2mmol/l
Question 4 Hypercalcemia : A) Is a daily problem in ICU B) Induces cardiac arythmia C) Is prevented by bisphophonates D) Is always associated with renal failure E) Requires hydratation
Clinical case 96-year-old patient admitted for arterial hypotension Severe diarrhea for 5 days with fever Her medications include thiazidique diuretic & ACE inhibitor for hypertension and insulin for diabetes. Arterial Pressure: 90/60, 125 beats/mn, clinical signs of deshydration, no urine in urinary catheter. Na 130mmol/l, K 6,8 mmol/l, Urea 45mmol/l, creatinine 610µmol/l, HCO3 17mmol/l, glycemia 12mmol/l
ECG
Hydratation and alkalinization Isotonic saline solution 1000ml + Sodium bicarbonate 14 1000ml Kayexalate 100g orally H1: diuresis restarts 50ml H0 H4 H8 H24 K 6.8 6.4 5.7 4.4 HCO3 17 18 20 21 Creatinine 610 594 555 502 Urinary output (ml/h) 25 50 60 65
Clinical case 25-year-old patient was admitted in emergency room for feeling faintness Clinical examination is normal, no fever No chronic medication Na 137mmol/l, K 7.8mmol/l, urea 3mmol/l, creatinine 54µmol/l, HCO3 22mmol/l. How do you manage hyperkalemia?