Micronutrient Requirements and Deficiencies

Micronutrient Requirements Micronutrient Requirements and Deficienciesand Deficiencies

Douglas L. Seidner, MD, FACGDouglas L. Seidner, MD, FACG

The Cleveland ClinicThe Cleveland Clinic

Digestive Disease CenterDigestive Disease Center

The ASPEN Nutrition Support Core Curriculum 2007


Composition of Body FluidsComposition of Body Fluids

Na+Na+ K+K+ Cl-Cl- HCOHCO33--

PlasmaPlasma 135-150135-150 3.5-53.5-5 98-10698-106 22-3022-30

GastricGastric 10-15010-150 4-124-12 120-160120-160 00

BileBile 120-170120-170 3-123-12 80-12080-120 30-4030-40

Sml IntSml Int 80-15080-150 2-82-8 70-13070-130 20-4020-40

DiarrheaDiarrhea 25-13025-130 10-6010-60 20-9020-90 20-5020-50

Sodium (Na)Sodium (Na)

• Total body Na is 40 mEq/kg (280 mEq in a Total body Na is 40 mEq/kg (280 mEq in a 70 kg patient)70 kg patient)

• One third fixed in boneOne third fixed in bone• Two thirds exchangeable (mostly Two thirds exchangeable (mostly

extracellular)extracellular)• Normal daily adult Na requirement is 1-2 Normal daily adult Na requirement is 1-2

mEq/kgmEq/kg• Renal Na reabsorption efficient (< 1mEq/L)Renal Na reabsorption efficient (< 1mEq/L)

Sodium (Na)Sodium (Na)

• Extracellular ionExtracellular ion• Usual dose 100-150 mEq/dUsual dose 100-150 mEq/d• This approximates 0.45%NS This approximates 0.45%NS • Added as acetate or chloride saltAdded as acetate or chloride salt

Sodium Deficit =Sodium Deficit =

0.6 x (wt in kg) x (140 – Na) + (140) x (Vol 0.6 x (wt in kg) x (140 – Na) + (140) x (Vol deficit in L)deficit in L)

HyponatremiaHyponatremia

• PrimaryPrimary – due to sodium loss – due to sodium loss

• SecondarySecondary – due to excess of free – due to excess of free water (most common)water (most common)

Primary HyponatremiaPrimary Hyponatremia

• GI lossesGI losses

• Fistula drainageFistula drainage

• Use of diureticsUse of diuretics

• Adrenal insufficiencyAdrenal insufficiency

Secondary HyponatremiaSecondary Hyponatremia

• Infusion of hypotonic solutionsInfusion of hypotonic solutions

• Excess ingestion of free waterExcess ingestion of free water

• Increased reabsorption of free water Increased reabsorption of free water (ADH)(ADH)

Symptomatic HyponatremiaSymptomatic Hyponatremia

• Chronic hyponatremia usually Chronic hyponatremia usually asymptomatic until Na < 110-120 asymptomatic until Na < 110-120 mEq/LmEq/L

• Acute hyponatremia can become Acute hyponatremia can become symptomatic if Na < 120-130 mEq/Lsymptomatic if Na < 120-130 mEq/L

Symptoms of HyponatremiaSymptoms of Hyponatremia

• HeadachesHeadaches

• ConfusionConfusion

• DeliriumDelirium

• SeizuresSeizures

• Coma Coma

Acute Hypotonic Hyponatremia(acute water intoxication <24hrs)

• < 125 mEq/L – headache, apathy, < 125 mEq/L – headache, apathy, nausea, confusionnausea, confusion

• < 115 mEq/L – seizures, coma< 115 mEq/L – seizures, coma




Estimating Sodium Requirement to Estimating Sodium Requirement to Correct Serum DeficitCorrect Serum Deficit

• mEq of Na needed = (desired Na- mEq of Na needed = (desired Na- measured serum Na) x .6 x body wt.measured serum Na) x .6 x body wt.(kg)(kg)

• Give no more than ½ the first dayGive no more than ½ the first day

• Rapid correction (>12mEq/day) can Rapid correction (>12mEq/day) can cause osmotic myelinolysis cause osmotic myelinolysis

HypernatremiaEtiology

• Excessive water loss exceeds Excessive water loss exceeds sodium losssodium loss

oror

• Excesive sodium intake exceeds Excesive sodium intake exceeds water intakewater intake


HypernatremiaSymptoms

• Symptoms if Na>160 acutely or >170 Symptoms if Na>160 acutely or >170 chronicallychronically

• Symptoms are neurologicSymptoms are neurologiclethargy and confusion, lethargy and confusion,

twitching, twitching, grand mal seizures, grand mal seizures, stupor and comastupor and coma

Treatment of HypernatremiaTreatment of HypernatremiaCalculation of Water Deficit (70 kg man Calculation of Water Deficit (70 kg man

with a serum Na of 160mEq/L)with a serum Na of 160mEq/L)

• Water deficit (L) = 0.60 x wt in kg x Water deficit (L) = 0.60 x wt in kg x [(serum Na/140) – 1][(serum Na/140) – 1]

• Water deficit (L) = 0.60 x 70 x Water deficit (L) = 0.60 x 70 x [(160/140) – 1] = 5.88 L[(160/140) – 1] = 5.88 L

Potassium (K)Potassium (K)

• Intracellular cationIntracellular cation• Usual dose is 60-120 mEq/d for PN patientUsual dose is 60-120 mEq/d for PN patient• Added as acetate or chloride saltAdded as acetate or chloride salt• Total body potassium falls ~370 mEq for Total body potassium falls ~370 mEq for

each 1 mEq/L fall in measured serum K each 1 mEq/L fall in measured serum K

Potassium (K)Potassium (K)

• Total body K is 50-55 mEq/kgTotal body K is 50-55 mEq/kg

• 98% is intracellular98% is intracellular

• Normal daily adult intake is 1 mEq/kgNormal daily adult intake is 1 mEq/kg

• Kidneys can decrease K excretion to Kidneys can decrease K excretion to no lower than 10 mEq/Lno lower than 10 mEq/L

PotassiumPotassium

• HypokalemiaHypokalemia can cause weakness can cause weakness and if severe psychoses and and if severe psychoses and paralysisparalysis

• HyperkalemiaHyperkalemia is more dangerous and is more dangerous and can cause EKG changes, can cause EKG changes, bradycardia, asystole, and vent. fib.bradycardia, asystole, and vent. fib.

Guidelines for Potassium TherapyGuidelines for Potassium Therapy

• For normal adults 40 – 60 mEq/day are For normal adults 40 – 60 mEq/day are given as IV replacement therapygiven as IV replacement therapy

• For K between 3.0 – 3.5mEq/L, 100 For K between 3.0 – 3.5mEq/L, 100 mEq will raise the serum K by 1 mEq/LmEq will raise the serum K by 1 mEq/L

• For K less than 3.0, 200 mEq will raise For K less than 3.0, 200 mEq will raise the serum K by 1 mEq/Lthe serum K by 1 mEq/L

• Do not exceed infusion rates of Do not exceed infusion rates of 20mEq/hour and recheck K after 40mEq20mEq/hour and recheck K after 40mEq

Hypokalemia and the ECGHypokalemia and the ECG

• Low voltageLow voltage

• Flattened or inverted T wavesFlattened or inverted T waves

• Prominent U wavesProminent U waves

• Depressed ST segmentsDepressed ST segments

• Widened QRS complex (K<2.0)Widened QRS complex (K<2.0)

Hyperkalemia and the ECGHyperkalemia and the ECG

• Flattenend P wavesFlattenend P waves

• Widened QRS complexesWidened QRS complexes

• Heart block, atrial asystoleHeart block, atrial asystole

• Sine wave, V FibSine wave, V Fib

Electrocardiogram

Hyperkalemia vs Acute MI

HyperkalemiaHyperkalemia – T wave is tall, narrow and symmetrical – T wave is tall, narrow and symmetrical

Acute MI Acute MI – T wave is tall but broad-based and asymmetrical– T wave is tall but broad-based and asymmetrical

HyperkalemiaHyperkalemia Acute MI Acute MI

Treatment of HyperkalemiaTreatment of Hyperkalemia

• 10 units of Insulin + 25 gm of glucose10 units of Insulin + 25 gm of glucose• 45 mEq NaHCO45 mEq NaHCO33

• 25 gm cation exchange resin in 20% 25 gm cation exchange resin in 20% sorbitol solution orally q. 4-6 h or;sorbitol solution orally q. 4-6 h or;

• 50 gm cation exchange resin in 1-200 50 gm cation exchange resin in 1-200 ml 35% sorbitol by enema q 4 hml 35% sorbitol by enema q 4 h

CHLORIDECHLORIDE

• Extracellular anionExtracellular anion• Osmotic pressure and acid base balanceOsmotic pressure and acid base balance• Chloride released as HCl as by-product of Chloride released as HCl as by-product of

amino acid metabolismamino acid metabolism• Acetate salts used to prevent hyperchloremic Acetate salts used to prevent hyperchloremic

acidosis acidosis • Administer as potassium or sodium saltAdminister as potassium or sodium salt

Chloride deficit (mM) =Chloride deficit (mM) =

0.5 x body wt (kg) – (Cl0.5 x body wt (kg) – (Cl--NORMALNORMAL

_ _ ClCl--MEASUREDMEASURED))

ACETATEACETATE

• Amino acid metabolism may produce Amino acid metabolism may produce metabolic acidosis resulting in ↑ metabolic acidosis resulting in ↑ bicarbonate requirementsbicarbonate requirements

• Bicarbonate changes pH; insoluble Bicarbonate changes pH; insoluble precipitate forms with calcium and precipitate forms with calcium and magnesium (never add bicarbonate magnesium (never add bicarbonate to PN solutions )to PN solutions )

• Acetate salts are converted to Acetate salts are converted to bicarbonate in the liverbicarbonate in the liver

• Functions as systemic alkalinizersFunctions as systemic alkalinizers• Use serum CO2 levels as a guideUse serum CO2 levels as a guide

CALCIUMCALCIUM

• Extracellular cationExtracellular cation• Usual dose 9-22 mEq/dUsual dose 9-22 mEq/d• Calcium gluconate yields 4.65 mEq/gramCalcium gluconate yields 4.65 mEq/gram

Corrected calcium concentration:Corrected calcium concentration:

Total CaTotal Ca2+2+CORRECTEDCORRECTED(mg/dl) = (mg/dl) =

Total CaTotal Ca2+2+MEASUREDMEASURED(mg/dl) + ([4 – albumin (g/dl)] x (mg/dl) + ([4 – albumin (g/dl)] x

0.8)0.8)

*ionized calcium level when in doubt*ionized calcium level when in doubt

PHOSPHORUSPHOSPHORUS

• Intracellular anionIntracellular anion• Usual dose 15-30 mM/dUsual dose 15-30 mM/d• 1 mEq potassium phosphate = 0.68 mM 1 mEq potassium phosphate = 0.68 mM

phosphate or 21 mg elemental phosphate or 21 mg elemental phosphorusphosphorus

• 1 mEq sodium phosphate = 0.75 mM 1 mEq sodium phosphate = 0.75 mM phosphate or 23 mg elemental phosphate or 23 mg elemental phosphorusphosphorus

MAGNESIUMMAGNESIUM

• Cation (primarily intracellular)Cation (primarily intracellular)• Usual dose 8-24 mEq/dUsual dose 8-24 mEq/d• Magnesium sulfate yields 8.12 mEq/gramMagnesium sulfate yields 8.12 mEq/gram

Corrected magnesium concentration:Corrected magnesium concentration:

Mg Mg CORRECTEDCORRECTED = Mg + 0.005[4.0-albumin (g/dl)] = Mg + 0.005[4.0-albumin (g/dl)]

Composition of Common Composition of Common Electrolyte SolutionsElectrolyte Solutions

SolutionSolution NaNa KK CaCa ClCl HCOHCO3 3 precursorprecursor

mOsmmOsm

Ringer’sRinger’s 130130 44 33 109109 2828 280280

SalineSaline 154154 154154 308308

D/5/WD/5/W 250250

D/D/5/0.45%N5/0.45%NaClaCl

7777 7777 405405

“ “

+ 20 KCl+ 20 KCl

7777 2020 7777 445445

ELECTROLYTE REQUIREMENTSELECTROLYTE REQUIREMENTS

Sodium 1-2 mEq/kg/dPotassium 1-2 mEq/kg/dChloride As needed for acid-base balance

Acetate As needed for acid-base balance

Calcium 11-15 mEq/dMagnesium 8-20 mEq/dPhosphorus 20-40 mEq/d

Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN2002;26S:22SA

Daily IV Electrolyte Daily IV Electrolyte RecommendationsRecommendations

• Calcium 4.5-22 Calcium 4.5-22 mEqmEq

• Phosphate 15-30 Phosphate 15-30 mMolmMol

• Magnesium 8-24 Magnesium 8-24 mEqmEq

• Sodium 60-150 Sodium 60-150 mEqmEq

• Chloride 100-150 Chloride 100-150 mEqmEq

• Acetate 10-150 Acetate 10-150 mEq/LitermEq/Liter

• Potassium 60-120 Potassium 60-120 mEqmEq

ReferencesReferences

• Langley G. “Fluid, Electrolyte, and Acid-Langley G. “Fluid, Electrolyte, and Acid-Base Disorders.” In Gottschlich MM, Base Disorders.” In Gottschlich MM, DeLegge MH, Mattox T, Mueller C, DeLegge MH, Mattox T, Mueller C, Worthington, Eds. The ASPEN Nutrition Worthington, Eds. The ASPEN Nutrition Spport Core Curriculum: A Case-Based Spport Core Curriculum: A Case-Based Approach-The Adult Patient. ASPEN, Approach-The Adult Patient. ASPEN, Silver Spring, MD, 2007, pp 104-128Silver Spring, MD, 2007, pp 104-128

• ““Estimating Nutritional Requirements.” Estimating Nutritional Requirements.” The Cleveland Clinic Foundation Nutrition The Cleveland Clinic Foundation Nutrition Support Handbook, Eds Parekh N, Support Handbook, Eds Parekh N, DeChicco R. 2004 pp 34-60.DeChicco R. 2004 pp 34-60.

Thank youThank you

Documents

Micronutrient Requirements and Deficiencies