fluid & electrolyte disorder -...

Fluid & Electrolyte Disorder 2015 Goals 1. Identify & develop complete pharmacotherapy plan for patient with fluid &/or electrolyte disorder 2. Explain pharmacotherapy recommendations Objectives 1. State common signs/symptoms of fluid & electrolyte disorders 2. Identify common causes of fluid, Na, K, Ca, Mag, phosphate disorders 3. Assess electrolyte depletion 4. Identify/Interpret laboratory/diagnostic information in determining fluid / electrolyte disorders 5. Develop complete pharmacotherapy plans for patients with fluid & electrolyte disorders Take home message Role of clinical pharmacist 1. Develop therapeutic plan using evidence-based medicine 2. Maximize outcomes 3. Minimize unwanted effects 4. Use most cost-effective therapies Pharmacotherapy Plan Template - 5

Problem Goal of therapy Pharmacotherapy Plan Monitoring strategy

1. Identify specific problem i.e. hypokalemia, hyperkalemia, severe hypercalcemia 2. Design appropriate therapy goal 3. Design patient specific pharmacotherapy plan 4. Design appropriate monitoring strategy to evaluate plan effectiveness

Pathophysiology Review – 7, 8, 9 1. Total Body Weight

• composition changes with age • younger you are → higher total body weight = fluid; % decreases with age

o adults = 50 – 60% o pediatrics = 65 - 70% o newborns = 70 – 75% o preemies = 75 – 80%

2. Fluid is contained in two compartments • intracellular compartment • extracellular compartment

o contains multiple components 1. interstitial 2. plasma/intravascular 3. transcellular

ICF = Intracellular fluid ECF= Extracellular fluid

Extracellular Space

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Fluid & Electrolyte Disorder 2015

Pathophysiology Review (Continued) 3. Fluid distribution example

Age Weight (kg) % Total Body H20 Total Liters Intracellular Extracellular (2/3 rds of total H20) (1/3 rd of total H20) Adult 70 50 % (presumed) 70(50%)= 35 L 35 L x 2/3rds = 24 L 11 L

Natural fluid distribution = 2/3rds intracellular; 1/3rd extracellular 4. IV Fluid Selection

• Must determine where fluids distribute • Osmolality of intracellular space = extracellular osmolality → ≈ 280 mOsm • D5W distributes just as natural fluid distribution occurs 2/3rds extracellular / 1/3rd intracellular

IV Fluid % distribution % distribution Intracellular Compartment Extracellular Compartments 1. D5W 2/3rds = 66.6% 1/3rd=33.3% 2. NS 0 % 100 % in all of the 3 extracellular compartments 3. Colloids 0 % 100 % plasma/intravascular part of extracellular space

• NS introduces sodium into the extracellular space changing the osmolarity of this space. This results in

differing osmolarity between the intracellular and extracellular spaces. End result → NS distributes to all of compartments within the extracellular space.

• IV fluids come in 4 different forms: http://catalogue.pearsoned.co.uk/samplechapter/0131186116.pdf

1. Crystalloids 2. Colloids 3. Blood / blood products 4. Oxygen-carrying solutions

Crystalloid – 9, 10 • a substance whose particles are smaller than those of a

COLLOID, form a true solution, and are therefore capable of passing through a semipermeable MEMBRANE

(http://medicaldictionary.thefreedictionary.com/crystalloid) • IV fluids containing varying concentrations of electrolytes http://catalogue.pearsoned.co.uk/samplechapter/0131186116.pdf • Crystalloids are classified based on tonicity • Tonicity describes the concentration of electrolytes

(solutes) dissolved in the water in comparison with that of body plasma (fluid that surrounds cells)

Crystalloid Concentration Definitions Isotonic Crystalloid 1. Iso = same Crystalloid concentration = plasma concentration 2. Tonic = concentration Tonicity of isotonic crystalloid = plasma tonicity Hypertonic Crystalloid 1. Hyper = high Crystalloid concentration > plasma concentration 2. Tonic = concentration Tonicity of hypertonic crystalloid > plasma tonicity Hypotonic Crystalloid 1. Hypo = low Crystalloid concentration < plasma concentration 2. Tonic = concentration Tonicity of hypotonic crystalloid is < plasma tonicity

Intravenous crystalloid fluids

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http://catalogue.pearsoned.co.uk/samplechapter/0131186116.pdf

http://medical-dictionary.thefreedictionary.com/colloid

http://medical-dictionary.thefreedictionary.com/semipermeable+membrane

http://medicaldictionary.thefreedictionary.com/crystalloid

http://catalogue.pearsoned.co.uk/samplechapter/0131186116.pdf

Fluid & Electrolyte Disorder 2015 Colloid IV Fluids -10 • IV fluids containing large proteins and molecules that tend to stay

within the vascular space (blood vessels) 1. Albumin; 2. blood products (i.e. PRBC, single donor plasma); 3. plasma protein fraction (Plasmanate); 4. synthetic colloids (hetastarch [Hespan R, Hextend R], dextran)

Pathophysiology Review -11 Osmolality = the measure of the number of dissolved particles in a fluid. https://www.google.com/?gws_rd=ssl#q=osmolality Where will the fluid bolus go in each example below? • 70 X 0.6 = 42 → 2/3rds = ICF = 28 L; 1/3 ECF = 14 L Intracellular osmolality is equivalent to the Extracellular osmolality → fluid freely moves between these spaces normally. Assumption: pt. has normal volumes: 28 L intravascular space; 14 L in extracellular space Example 1: Adult; 70 kg.; D5W 1500 ml bolus Example 2: Adult; 70 kg; NS 1500 ml bolus Example 3: Adult; 70 kg; D5NS 1500 ml bolus

Intracellular Extracellular Osm 280 280 Normal Vol. 28 L 14 L Add Volume After Addition Volume After Addition D5W 29 L 14.5 L ↑ 1 L; 2/3rds of 1500 ml ↑ 0.5 L; 1/3rd of 1500 ml NS 28 L 15.5 L No change ↑ 1.5 L; all 1500 ml D5NS 28.5 ml 15 L ↑ 500 ml D5W ↑750 ml NS + 250 ml ↑ D5W

D5NS: ½ volume = 750 ml is NS and ½ volume = 750 ml is D5W NS (750 ml): All 750 ml distributes into the extracellular space. D5W (750 ml): 2/3rds (66.6 % x 750 ml ≈ 500 ml) distributes into the intracellular space;

1/3rd (33.3 % x 750 ml ≈ 250 ml) distributes into the extracellular space Dextrose distributes into intracellular & extracellular compartments in a 2/3rds, 1/3rd distribution.

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https://www.google.com/?gws_rd=ssl%23q=osmolality

Fluid & Electrolyte Disorder 2015 Volume depletion can result in Δs in hemodynamics, behavior, thirst, mucous membranes, etc. - 13

Physical Exam Mild Moderate Severe 1. Weight loss: • Peds 5 % 10 % 15 % • Adults 3 % 4-6 % 7-9 % 2. Pulse Normal Slight ↑ Very ↑ 3. BP Normal Normal - orthostatic Orthostatic to shock 4. Behavior Normal Irritable, thirsty Hyper irritable to lethargic 5. Thirst Slight Moderate Intense 6. Mucous membranes Normal Dry Parched 7. Tears Present Decreased Absent 8. Ext. jugular vein Visible when supine Not visible Not visible 9. Skin Capillary refill < 2 sec Slowed 2-4 sec Very delayed > 4 sec 10. Urine specific gravity > 1.020 > 1.020; oliguria Oliguria/anuria

Indications for Fluid Management - 14 1. Expand intravascular volume 2. Correct imbalance in fluid or electrolyte 3. Manage fluid and electrolyte needs in an ongoing disease state where there is continuous loss 4. Daily fluid maintenance

Fluid Selection for Volume Expansion – 15, 16 Questions to Ask 1. What compartment needs volume? 2. What fluid will fill that compartment?

• NS, LR, PRBC, hetastarch, or albumin 3. What factors justify the selection?

Infusion rates are based on fluid, age, & condition - 16

Age Rate Monitoring Adult Any acceptable rate BP hourly Pediatric > 1 yr. 20 ml/ kg bolus HR hourly Pediatric > 0-1 yr. 10 ml/ kg @ 10 ml/hr. bolus HCT Neonate Albumin 5 % @ 10 ml/ kg. bolus K +/- all lytes 1. Adults usually can accept any rate except those with: heart

failure; renal failure; or end stage liver failure 2. Clotting factors may not be necessary unless giving multiple

blood products/large volumes of crystalloids 3. ABG only necessary in shock state with acid – based disorders

I/O daily ABG +/- Clotting factors +/-

Fluid Compartment Justification NS Extracellular Shock, hypotension, immediate LR Extracellular Shock, hypotension, acidemia present PRBC Intravascular Add to a crystalloid, acute blood loss present Hetastarch Intravascular Add to crystalloid to sustain longer results when albumin is low & not due to blood loss Albumin Intravascular Acceptable only when serum albumin < 2 gm/dl & cause not due to blood loss

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Fluid & Electrolyte Disorder 2015 Maintenance Fluid Requirements - 17 • Goal: balance input/output

Maintenance Needs Calculation Holliday – Segar Weight (kg) ml/kg/Day 1-10 100 11-20 50 >20 20 Holliday – Segar method classic for pediatric; also used in adults; In adults most often 30 To 35 ml/kg/day used.

Practice time – 18, 19 Calculate maintenance/electrolyte needs for 65 kg. pt. Holliday-Segar Method:

Weight ml/kg/Day 10 kg 100 ml/kg (10 kg)/day = 1000 ml 10 kg 50 ml/kg (10 kg)/day = 500 ml 45 kg 20 ml/kg (45 kg)/ day = 900 ml Total Maintenance Fluids 2,400 ml / day

30-35 ml/kg/day method: 35 ml/kg/day (65 kg) = 2,275 ml/day Assumption: Volume loss = 2,300 ml

Average Electrolyte Losses Electrolyte mEq lost / 100 ml/day Na 3 K 2 Cl 2

Estimated Electrolytes Lost/Day - 19 Electrolyte mEq lost / 100 ml/day Maintenance Volume Total lost/day Na 3/100 ml x 2,300 ml 69 mEq/day K 2/100 ml x 2,300 ml 46 mEq/day Cl 2/100 ml x 2,300 ml 46 mEq/day

Fluid selection: Multiple solutions are appropriate i.e. D51/4 NS; NS¼ K+: 46 mEq/ 2,300 ml =0.02 mEq/ml; 0.02 mEq/ml x 1,000 ml = 20 mEq per liter IV bag Rate: 2,300 ml/24 hrs. = 90 ml/hr.

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Fluid & Electrolyte Disorder 2015 Volume Depletion (Replacement) - 20 • Determine cause of volume loss • Goal: immediate deficit correction (fluid; lytes); correct cause • Plan: Correct Volume losses within 24 hrs.

1. 50 % volume correction in 8 hrs. 1,200 ml/8 hrs. = 150 ml/hr. x 8 hrs. 2. 50 % correction in remaining 16 hrs. 1,200 ml/ 16 hrs. = 75 ml/hr. x 16 hrs.

Electrolyte Loss by Specific Body Fluid (losses/L of fluid) - 21

Fluid Na Cl K HC03 Volume(ml)/day Liters/day Saliva 60 15 26 50 1500 1.5 L Gastric (NG Tube) 60-100 100 10 0 1500-2500 1.5-2.5 L Duodenal 130 90 5 0-10 300-2000 0.3-2.0 L Bile 145 100 5 15 100-800 0.1-0.8 L Pancreatic 140 75 5 115 100-800 0.1-0.8 L Ileal 140 100 2-8 30 100-9000 0.1-9.0 L Diarrhea 120 90 25 45 ---

Practice – 22, 23, 24 Jimmy, 3 yr. old; 36 “; 12 kg; lethargic Family attending family reunion outside all day. Both parents thought Jimmy had been taking in fluids. Neither parent knew how frequently he urinated or how much. Outdoor temperature = 90 0 F + with 60 % humidity Physical exam: hypotensive; tachycardic; weak pulses;

skin turgor tented for 3 seconds; mucous membranes dry

1. What is the problem? 2. What is the intervention? 1. Volume loss 20 to lack of intake and great insensible losses

Volume loss estimate = 10 % (See Volume Depletion Chart bottom pg. 3 of notes- Based on physical exam noted above- pt. is moderately volume depleted which = 10% estimated volume loss): (12 kg) (10 %) = 1.2 L. Electrolyte loss estimate (profuse sweating) (see table bottom pg. 4:

Electrolyte mEq loss/100 ml/day Total Loss Na (1200 ml)(8 mEq/100 ml) 96 mEq K (1200 ml)(6 mEq/100 ml) 72 mEq Cl (1200 ml)(6 mEq/100 ml) 72 mEq

Volume Depletion Electrolyte Losses Electrolyte mEq lost/100 ml/day Na 8 K 6 Cl 6

Volume Depletion Electrolyte Losses Electrolyte mEq lost/100 ml/day Na 8 K 6 Cl 6

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Fluid & Electrolyte Disorder 2015 Plan – Replace the lost 1.2 Liters, over 24 hrs. 20% as a bolus; 50% of remaining volume over 8 hrs; remaining volume replaced over 16 hrs. • NS 240 ml (20% of loss) bolus leaving 960 ml (1200ml-total lost – 240 ml bolus = 960 ml)

Bolus given because symptomatic • Then, 60 ml/hr. x 8 hrs.= 480 ml (this is ½ or 50% of 960 ml) • Then, 27 ml/hr. x 16 hrs. = 480 ml • Add K+ once pt. urinates • Once ECF volume is replaced, may change fluid to D51/2NS

Practice Continued = 25 If Jimmy needed long term care in the hospital, what change should be made to recommendation? 1. Daily maintenance calculation using Holliday-Segar Method:

• Pts. normal wt. = 13 kg. • (10 kg)(100 ml/kg) + (3 kg)(50 ml/kg) = 1000 ml + 150 ml = 1150 ml • Fluid could be dextrose +/- saline

Extra Insensible Loss – 26 • Add 12 % for each 1 degree > 37.80 C (rectally) / 24 hr. • Other settings: add 0-30 %/ 24 hr.

1. hyper metabolic conditions such as: trauma; burns; sepsis 2. status epilepticus (continuous active seizure)

Practice - 27 7 month old; diarrhea x 3 days; symptomatic of fluid loss Current wt. 10 kg; normal wt. 11 kg Outline your steps and recommend a plan. Practice - 28 1. Symptomatic: give bolus (10 ml/kg) (10 kg) = 100 ml 2. Volume deficit: = 1 kg so 1 L

• Volume remaining: 1,000 ml – 100 ml (bolus) = 900 ml • 900 ml x 50 % = 450 ml. 450 ml/8 hrs.≈ 55 ml/hr. • Then, 450 ml/16 hrs. = 28 ml / hr. • Electrolyte depletion (refer to Electrolyte Lost by Fluid Type Table pg.6)

Maintenance: • (10 kg)(100 ml/kg) + (1kg)(50 ml/kg) = 1050 ml • + daily output

Electrolyte mEq lost /L / day Diarrhea Pt. Volume loss Electrolyte Deficit Na 120 1 , 000ml (= 1kg) 120 mEq K 25 1 , 000ml (= 1kg) 25 mEq

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Fluid & Electrolyte Disorder 2015 Practice - 29 42 yr. old; crohn’s pt. post GI surgery with JP drain placement. Currently NPO, including fluids. Ht. 6’3”; Wt. 72 kg. BP 120/80; HR 90 BPM; RR 12 BPM; T0 39.20 C (rectal) I/O: 1000/2350 (JP 1750 ml) What to do? Q1: Is pt. volume deficient? Yes Input = 1000 ml; Output (TOTAL) = 2350 ml + 1750 ml (JP Drain) + 457 ml (fever) = 4,557 ml Q2: Does pt. need volume replacement? Q3: What is his daily maintenance needs? Assessment - 30 Fever losses = (Temperature variance) x [12 % x Daily Maintenance] (1.5)[(12%) (2540)] = 457 ml Replacement:

Maintenance: Holliday-Segar Method:

Weight ml/kg/Day 10 kg 100 ml/kg (10 kg)/day = 1000 ml 10 kg 50 ml/kg (10 kg)/day = 500 ml 52 kg 20 ml/kg (52 kg)/ day = 1040 ml Total Maintenance Fluids 2540 ml / day

Electrolyte JP Loss mEq /1000 ml Loss Total to replace Na 1750 ml 130 = 228 mEq K 1750 ml 5 = 9 mEq

Order: Start: NS + 10 mEq KCL @ 105 ml x 8 hr. Then, 55 ml/hr. x 16 hrs. (Replaces JP drain losses ≈ 1750 ml) Convert to: D5NS + 10 mEq KCL @ 200 ml 1750 ml + 457 ml + 2540 ml = 4747 ml

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SODIUM DISORDERS Causes Na Disorders – Gains, Losses, Disruption - 32

Sodium Disorder Causes – 32,33 Depletion of Effective SIADH Hormonal Δs Advanced 10 Polydipsia Low Salt Intake Circulating Volume Kidney Failure 1. True Volume 1. Adrenal 1. ↓ filtration 1. Ecstasy 1. Beer Drinkers

depletion insufficiency volume (May also Potomania 2. Heart Failure 2. Hypothyroidism Stimulate ADH) 2. “Tea & Toast” 3. Cirrhosis severe Diet 4. (?) Nephrotic 3. Reset Osmostat

Syndrome (i.e. pregnancy) 5. Thiazide diuretics

Drug Induced HYPOnatremia – 34

Drug Induced HYPOnatremia - 34 ADH analogs ↑ ADH release Potentiate ADH Effects ??? Etiology DDAVP Antidepressants Acetaminophen Amitriptyline Oxytocin Antipsychotics Chlorpropamide Fluoxetine Carbamazepine Cyclophosphamide Fluphenazine Chlorpropamide NSAIDs Haloperidol Ifosfamide Thioridazine Narcotics Thiothixene Nicotine Vincristine

Na & H20 follow one another – sodium is married to water - 35 Volume Assessment (Always Assess)

1. Physical Exam 2. Serum osmolality – See calculation below & MEMORIZE it

Serum Osmolality (sOsm) = 2(Na) + (BUN/2.8) + (glucose / 18) Uosm = Urine osmolality Una = Urine sodium Steps to solving Sodium Problems Step 1: What is the patient’s volume status? Step 2: Is the patient isotonic? (serum osmolality – sOsm) Step 3: Determine if other disease states are present. Step 4: Assess urine and Na osmolality.

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SODIUM DISORDERS - 36

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SODIUM DISORDERS Steps to solving Sodium Problems - 37 Step 1: What is the patient’s volume status? Step 2: Is the patient isotonic? (serum osmolality – sOsm) Step 3: Determine if other disease states are present.

Do they link if another present? Step 4: Assess urine and Na osmolality.

Assess if Na+ disorder suspected. Case 1 - 38 23 yr. old male with watery diarrhea. Comes to ER lightheaded and tachycardic. Not orthostatic. Has dry mucous membranes. Neurologic exam is normal. Pt is alert. Lab results: Na+ 129 / Cl- 95 / BUN 5 / BG 75 / K+ 4.2 / HC03 24/ SrCr 0.8 sOsm = 2(129) + (5/2.8) + (75 / 18) sOsm = 258 + 1.79 + 4.17 = 263.96 Ht. 6’2”; Wt. 70 kg. (current), 80 kg. baseline BP: 90/53; HR 115; RR 16 Urine Osm = 520 (concentrated urine) Urine Na = 5 Case 1 Pharmacotherapy Plan – 39, 41 1. Estimate ECFV deficit 2. ECF volume deficit Equation:

[(TBWn) (0.6) (0.33)] - [(TBWc) (0.6) (0.33)] → KNOW THIS CALCULATION

3. [(80kg)(0.6)(0.33)]-[(70kg)(0.6)(0.33)] = 2 L volume depleted Note: 0.6 = % of body that is water; 0.33 = % of body water wt. in extracellular space. What to use for IV Fluid

Case 1 Pharmacotherapy Plan - 42 Problem Goal Plan Monitoring 1. HYPOvolemia 1. Correct ECFV NS 100 ml/hr. x 2 L 1. Na+ q 24 hrs. 2. HYPOtonic deficit. 2. I/O daily 3. HYPOnatremia 2. ↑ Na 0.5mEq/hr. 3. VS (BP;HR) 4. Wt. daily

Pg.10 of notes

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SODIUM DISORDERS Case 2 - 43 82 yr. old female admitted from nursing home with ↑ lethargy & confusion. Baseline: dementia. Normally animated & interactive. Poor appetite x 1 yr. with significant wt. loss. Currently eats very little. Hydrochlorothiazide added 2 weeks ago to medications. N/V x several days. No diarrhea; fever or other complaints. Physical Exam: Dry oral mucosa; no orthostasis; no evidence of CHF; ascites or edema. Awake but lethargic. Neuro exam normal. Labs: Na+ 121 / Cl 91/ BUN 6/ K+ 5.3/ HC03 22/ SrCr 0.4/ BG 83 Na+ four weeks prior: 138 mEq/ L Urine Osm: 220 Urine Na+ 30 Steps to solving Sodium Problems Step 1: What is the patient’s volume status? Step 2: Is the patient isotonic? (serum osmolality – sOsm) Step 3: Determine if other disease states are present. Step 4: Assess urine and Na osmolality. 1. What is the problem? 2. What is the treatment goal? Syndrome of Inappropriate Antidiuretic Hormone (SIADH) - 45

Syndrome of Inappropriate Antidiuretic Hormone (SIADH) SIADH Criteria Lab Values SIADH Causes H20 intake > output 1. Urine osmolality > 100 mOsm 1. Cancers 2. Urine Na > 20 mEq/L 2. CNS disorders 3. Pulmonary disorders 4. Drugs 5. Hypothyroidism

Drugs that Induce SIADH (See Table pg. 9 Also) - 46

Drugs that Induce SIADH Antineoplastic Antipsychotics Carbam

azepine DDAVP NSAIDS Diuretics Opiates SSRI

* TCAs Li++ Ecstasy

Cyclophosphamide Chlorpropamide ibuprofen Thiazides MS04 Amitriptyline Vincristine Haloperidol meperidene Imipramine Thioridazine Thiothixene

*SSRIs: fluoxetine; sertraline SIADH vs H20 Intoxication Differences

SIADH vs H20 Intoxication Differences - 47 Clinical Disorder Urine Sodium Urine Osmolality SIADH > 20 mEq/L > 100 mOsm/kg H20 < 20 mEq/L < 100 mOsm/kg

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SODIUM DISORDERS Case 2 Pharmacotherapy – 48, 49, 50

Baseline Na+ = 138 mEq/L Serum Na+ < 125 mEq/L associated with seizure disorder Serum Na+ Correction:

• Serum Na+ Correction: 0.5-1.5 mEq/L/hr. 1. → Rate limited by hr. & day 2. Corrections > 1.5 mEq/L/hr. could result in sentinel event!

• Maximum Na+ correction: 12 mEq/L/Day 1. Prevents cerebral edema complications 2. Prevents i.e. Osmotic demyelination

• Na Δ = [IVNa-SNa] ÷ [(total body H20) + 1] BW = Total Body Water in Liters → estimated as a fraction of body wt. (kg)

• Children & men < 70 yrs.: 0.6 x wt. (kg) • Men > 70 yrs.: 0.5 x wt.(kg) • Women > 70 yrs.: 0.45 x wt. (kg)

Designing Plan of Care

Problem Goal Plan Monitoring SIADH 1. Correct Na 1. H20 restriction &/or 1. Na+ q 1-2 hrs. till normal 2. Restrict H20 2. IVF = NS @ 100 ml/hr. x 3 L 2. I/O 3. Wt. daily 4. Labs: K+. Mg++ daily

Cells swell as fluid is repleted → to this too fast → demyelination can occur leading to death. Rate Calculation to ↑ Na+ by 0.5 mEq/L/hr. 1.4 mEq/L (Na+ Δ) ÷ 1000 ml = 0.5 mEq/L/hr. (Na+ Serum Correction) ÷ X ml X ≈ 360 ml → 360 ml/hr. might be too aggressive → maybe consider 3% NaCl Questions and Considerations 1. Can pt. tolerate volume i.e. 360 ml/hr.? 2. 3% NaCl → caution when using this concentrated of solution

• 3% NaCl = Na+ → 513 mEq/L

Problem SIADH Goals 1. Induce (-) H20 balance 2. Correct SIADH cause – drug Tx. 3. Maintain Na+ > 125 mEq/L

Case 2 SIADH – Intervention; Plan Goal Correct Na to 125 mEq/L minimum with NS NS = 154 mEq Na+/L Na Δ = [IVNa-SNa] ÷ (total body H20) + (IV Volume) = (154 mEq/L – 121 mEq /L) ÷ [(0.45)(50) + 1 L] = 1.4 mEq/ L → = 3 L to achieve goal = 125 mEq/L

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SODIUM DISORDERS Recommendations in Heart Failure - 51 1. Heart failure means volume limitations

Is there another IV solution that can be used in HF?

2. Na Δ = [IVNa-SNa] ÷ [(total body H20) + 1 L] Na Δ = (513 mEq/L – 121 mEq/L) ÷ [(0.45) (50) + 1 L] Na Δ = 17 mEq/ L or 1.7 mEq/ 100 ml

3. How many ml to achieve Serum Na+ = 125 mEq/L? 1.7 mEq/ 100 ml = 0.5 mEq/hr. / X ml X ≈ 30 ml/hr.; 235 ml = 4 mEq

4. How many ml to achieve Serum Na+ = 135 mEq/L? 135 mEq/L – 121 mEq/L = 14 mEq 235 ml/4 mEq = X / 14 mEq X ≈ 823 ml

5. Can this be replaced in 24 hrs? NO! Cannot be replaced in 24 hrs. → See Case 2 Pharmacotherapy pg. 13 notes Maximum Na+ correction: 12 mEq/L/Day

1. Prevents cerebral edema complications 2. Prevents i.e. Osmotic demyelination

Chronic SIADH Management - 52 1. H20 restriction 2. Alternatives when H20 restriction not enough

• Demecloycline 300 mg PO BID or QID • Tolvaptin 15 mg PO daily, may ↑ to max dose = 60 mg/day • NaCl 900 mg PO daily + loop diuretic (not usually considered)

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SODIUM DISORDERS Case 3 - 53 50 yr. old male; Heart Failure 20 to MI. Admitted to hospital with: dyspnea on exertion; orthopnea;

paroxysmal nocturnal dyspnea Current TX: Lisinopril; furosemide → ran out 1 week ago Physical Exam: Jugular venous distention; rales over lower ½ of lung fields; Normal S1 & S2 heart sounds. S3 gallop present at apex. 2+ pitting edema lower extremities. Vitals: BP 110/70; HR 110; RR 20 Labs: Na+ 130/ Cl 94/ BUN 28/ K+ 3.8/ HC02 25/ SrCr 1.1/ Glucose 116 Urine Osm 600 / Urine Na 10 Case 3 Pharmacotherapy Plan - 55

Problem Goals Plan Monitoring 1. HYPERvolemia Remove excess H20 1. Restrict H20: 1 L/day Volume status daily 2. HYPOtonic 2. Restrict Na+ to 2 gm/day Na+ daily 3. HYPOnatremia 3. Optimize HF Meds • ACEi • ARB • +/- diuretic

Tachycardia pushes fluid in extracellular space → start NS to fill space. Continue NS or change

Pg. 10 of notes

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Fluid & Electrolyte Disorder 2015 Case 4 - 56 14 yr. old male found unresponsive. Pt. not seem by mother x 24 hrs. She found him lying on couch unresponsive. Copious quantity of black colored vomit evident. Pt. is diabetic; self-administers medications. Last medications taken: unknown. Pt. offers no history. Physical Exam - 57 BP 101/72; HR 123; RR 32; T0 Oral 34.80 C; Pulse oximetry 100 % room air. Wt. = 65 kg. Response to questions with moans. Responsive only to loud or painful stimuli. Head/neck normal except for oropharynx: very drug mucous membranes; moderate dried, black hemocult (+) material. Lungs: clear to auscultation; breathing pattern: Kussmaul (rapid & deep breathing) Abdomen: Negative Labs - 58 Na+ 162/ Cl 87/ BUN 32/ K+ 5.2/ HC02 5/ SrCr 1.5/ Glucose 782 ABG: 6.92 / 9 / 98 Urine: Ketone +; WBC +; WBC 22,000; Hgb/HCT 14.4 / 43.5 Paramedic TX Course: Accucheck “too high to read”. Peripheral line inserted; IV fluids = NS @ 200 ml/hr. Pt. Problem List: 1. DKA; 2. Volume depletion; 3. Acid/Base disturbance; 4. R/O UTI Case 4 Problem List - 59 Na+ Assessment 1. Na+ needs correction in setting of hyperglycemia

↑ 100 mg/dL glucose = ↓ 1.7 mEq/L Na+ [(782-100) ÷100] (1.7 mEq/L) + 162 mEq/L ≈ Na+ of 166 mEq/L

Volume Assessment (Depletion) 2. Volume Deficit = (Present TBW) x [(Sr Na+ ÷140) - 1]

Volume Deficit = (0.6) (65 kg) x [(166 mEq/L ÷ 140) - 1] Volume Deficit ≈ 7.24 L

1 kilogram (kg) = 1 liter (l). Kilogram (kg) is a unit of Weight used in Metric system. http://metric-calculator.com/converter_kg_to_liter.htm Question: What IV Fluid to use? Case 4 Pharmacotherapy Plan -60

Problem Goals Plan Monitoring 1. HYPOvolemia 1. Correct volume 1. Begin IVF = NS until ECF 1. Volume status daily 2. HYPERtonic 2. Correct glucose volume is filled - (BP) 2. Chemistries q 2 h & daily 3. HYPERnatremia 3. Replace lytes 2. Then, switch to IV fluids 4. Treat infection with dextrose +/- saline

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http://metric-calculator.com/converter_kg_to_liter.htm


HYPERnatremia (Na > 145 mEq/L)

HYPERnatremia (Na > 145 mEq/L) - 61 Findings Problem Signs/Symptoms ↓ total body H20 relative Inadequate H20 intake to total serum Na + 1. Net H20 loss 1. Defective thirst mechanism 1. Anorexia 2. Na+ gain 2. Lack access to H20/Fluid 2. Coma 3. Unable to take in H20 3. Insomnia 4. Lethargy 5. Muscle weakness 6. Restlessness 7. Seizures 8. Tachypnea

HYPERnatremia Etiologies - 62

10 Sodium Excess 10 Water Loss 1. Excess Na+ intake 1. Poor H20 Intake 2. ↓ urinary Na+ excretion • Impaired H20 access

• Hyperaldosteronism (i.e. infants; elderly w. dementia) • Impaired thirst sensation • Hypothalamic lesions 2. Increased Urinary H20 Loss • ADH deficiency (Central DI) • ADH resistance (Nephrogenic DI) 3. Increased GI loss of H20

Classifications HYPERnatremia – 63, 64

HYPOvolemia, HYPERnatremia - 63 Euvolemia, HYPERnatremia - 64 Causes Causes

Extra renal loss Urine Na+ < 10 mEq 1. Profuse sweating 1. 10 polydipsia Osmolality > 700 mOsm/kg 2. Open skin • Thirst center • Burns destruction • Pemphigus vulgaris 1. Hypothalamic tumors 3. GI losses 2. Granulomatous disease 3. Trauma Renal Loss Urine Na+ > 20 mEq/L 1. Diuretics 1. Central DI Osmolality < 700 mOsm/kg 2. Severe osmotic diuresis 2. Nephrogenic DI

Diabetes Insipidus (DI) – Euvolemia, HYPERnatremia - 65

Characteristics 1. Normal ECF 2. Slight ↑ serum Na+ 3. Urine volume > 3 L/day → This is key → high urine output > 3 L /day. Diagnosis 1. H20 deprivation test. Detects Δs in urine Osm Central DI: urine Osm > 600 mOsm/kg Nephrogenic DI: Urine Osm ≤ 300 mOsm/kg

To determine Central DI vs. Nephrogenic DI → do H20 deprivation test → measure Δ in urine Osm

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HYPERnatremia (Na > 145 mEq)

DI (Euvolemia, HYPERnatremia) Treatment by Type -66 Problem Goals Plan (Therapy) Monitoring Central DI 1. ↓ urine volume to 1.5-2 L/day 1. Intranasal Desmopressin 1. Serum Na+ q 3-4 days initial 10 mcg. daily Then, q 2-4 months 2. Adjust dose to urinary 2. Urine output daily concentration to prevent Nocturia, 1.5-2 L/day Nephrogenic 1. Correct hypocalcemia 1. Na+ ≤ 2 gm/day 1. Serum & urine Na+ Osm DI 2. Correct hypokalemia if present 2. Thiazide diuretic Q 2-4 months 2. Urine output daily

HYPERvolemia, HYPERnatremia (Rarely Occurs) - 67

Cause – excess Na+ Ingestion Plan (Therapy) Monitoring 1. Volume resuscitation excess & ↑ volume 1. Loop diuretic 1. Na+ q 2-4 hrs. 2. CPR administration of NaHC03 * 2. Free water 2. Na+ q 6-12 hrs. once Na+ < 148 mEq/L

* Part of ACLS for cardiovascular collapse. Shortly post, √ Na+ → if high → usually resolves. If not, refer to treatment.

Edema Causes - 68 Obstruction of Lymph Fluid ↑ Capillary pressure ↓ Colloidal Osm Pressure ↑ Capillary Permeability 1. Malignant obstruction 1. ↑ Vascular volume 1. ↑ loss plasma proteins 1. Inflammation 2. Lymph node removal i.e. HF, CKD i.e. CKD, burns 2. Allergic reaction Thiazolidinedione TX 2. ↓ production plasma 3. Malignancy (Glitizone) proteins 4. Tissue injury / burns 2. Venous obstruction i.e. liver disease Liver disease i.e. malnutrition Acute pulmonary edema 2. ↓ arteriolar resistance Ca++ blockers

Edema - 70

Problem (Finding) Goal Plan (Therapy) 1. ↑ interstitial volume 1. Minimize/reduce 1. EF > 30% + GFR > 50 ml/min

Physical exam noted as tissue edema Hydrochlorothiazide 25-50 mg/day ≥ 2+ edema +/- Spironolactone 25-50 mg/day

2. EF < 30 % Furosemide 40 mg q 8 hr.

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POTASSIUM

HYPOkalemia Causes K+ < 3.5 mEq/L) - 74 ↓ K+ Intake Excess Renal Loss Excess GI Loss K+ Transcellular Shifts 1. Diet, inability to eat 1. Diuretic TX 1. Vomiting 1. β-Adrenergic agent

K+ free parenteral 2. Renal failure 2. Diarrhea 2. Insulin administration Nutrition (PN) 3. 10 Hyperaldosteronism 3. GI Suction 3. Alkalosis

4. Corticosteroid TX 4. GI Fistula drains

Drug Induced HYPOkalemia (K+ < 3.5 mEq/L) - 76 MOA Drug Class Agents Transcellular Shifts - 76 Β2 Receptor Agonists 1. Epinephrine 2. Albuterol 3. Terbutaline 4. Salmeterol 5. Ephedrine 6. Pseudoephedrine Tocolytic agents 1. Ritodrine Theophylline Caffeine Neonatal Population Insulin Overdose Enhanced Renal Excretion - 77 Diuretics 1. Acetazolamide 2. Thiazides 3. Metolazone 4. Furosemide 5. Torsemide 6. Bumetanide 7. Ethacrynic Acid High dose PCN 1. Nafcillin (Sometimes attributed 2. Ampicillin to rate of infusion) 3. Penicillin Mineralocorticoids Aminoglycosides Waste K+ Amphotericin* Waste K+ Cisplatin Waste K+ Enhanced Fecal Excretion - 78 Sorbitol** In many preparations Sodium polystyrene Kayexalate

* Amphotericin – K+ wasting not seen much with colloidal ** Elixirs have sorbitol

HYPOkalemia Signs / Symptoms - 79 ↓ Urine Conc. GI Neuromuscular CV CNS Acid/Base 1. Polyuria 1. Anorexia 1. Cramps 1. EKG Δs 1. Confusion 1. Metabolic 2. Polydipsia 2. N/V 2. Tenderness Wide QT 2. Depression Alkalosis 3. Low urine Osm 3. Abdominal 3. Paresthesias 2. Dysrhythmias distension 4. Paralysis 3. Hypotension 4. Paralytic ileus

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POTASSIUM Potassium Related EKG Δs - 80 HYPOkalemia – ↓ K+ → QT Interval widens

HYPERkalemia – Peaked T Waves

Case 1 HYPOkalemia - 81 67 yr. old; tired; weak seen by MD for routine visit. Pt. states “weeds are out of control & tired from too much work”. PMH: HTN; Non-Insulin dependent diabetes; glaucoma Meds: Furosemide 20 mg daily; diltiazem 90 mg QID; metformin 500 mg BID Physical Exam: Unremarkable except extremities & mucous membranes dry. Labs: Na+ 154 / Cl 98 / BUN 15 / K+ 3.1 / HC03 22 / SrCr 1.6 Glucose 87 / Ca++ 8.7 / Ma+ 1.5 / P04 2.9

HYPOkalemia Treatment – 81-84 Problem Goal Plan HYPOkalemia 1. Identify/treat 1. Assess correction target underlying cause Mild: 3-3.5 mEq/Lee – oral TX 2. Identify treatment Moderate: 2.5-3 mEq/L – IV or PO route Severe: < 2.5 mEq/L – must be IV 3. K+ w/i normal limits 2. Provide TX see below Monitoring see pg. 21 of notes

K+ Supplementation Key Concepts For every 10 mEq K+ replaced → serum K+ ↑ 0.1 mEq/L K+ = 3.1 → give 40 mEq K+ to ↑ K+ to 3.5 mEq ALWAYS use safe practices with IV K+ (usually 10 mEq/hr. used)

K+ Supplementation Formulation Dose Indication Oral K+ 20-80 mEq/day divided doses Non-urgent or maintenance Oral K+ Liquid 40-60 mEq/day Urgent not emergent IV K+ 10-40 mEq/hr. (usually 10 mEq/hr.) Severe

T Wave

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POTASSIUM

Monitoring K+ Supplementation Sustained release oral K+ product must wait longer than 2 hrs. for K+ recheck

Monitoring K+ Supplementation Parameter Frequency of Recheck Range 1. K+ 1. Post every 80 mEq > 3.5 mEq/L < 5 mEq/L 2. 1 hr. post IV; 2 hr. post PO → Longer for sustained release 2. EKG (underlying CV prob.) Continuous Convert to NSR 3. EKG (underlying CV prob.) Continuous Lack of V-Fib; V-Tach 4. Digoxin Concentration Once < 2.5 ng/ml 5. Infusion site pain Q 1 hr. Minimal to none 6. Weakness, √ for resolving Q 1 hr. Minimal to none 7. Nausea, √ for resolving Q 1 hr. None

HYPERkalemia (> 5 mEq/L) Causes (85)

Excessive Intake Intracellular Aldosterone ↓ Renal Elimination Intake > Output Compartment Release 1. Diet 1. Burns 1. No response 1. Renal failure 2. PO supplements 2. Crush injuries 2. Adrenal insufficiency 3. Parenteral 3. Extreme exercise 3. TX with K+ sparing

Nutrition (PN) 4. Rhabdomyolysis diuretics 5. Seizures 4. ACEi TX 6. Tissue trauma

HYPERkalemia Signs/Symptoms (86) GI Neuromuscular CV 1. Diarrhea 1. Dizziness 1. EKG Δs 2. Intestinal 2. Muscle cramps peaked T waves

cramps 3. Paresthesias 2. Risk cardiac arrest 3. N/V 4. Weakness

21│Renal


POTASSIUM Case: HYPERkalemia – 88, 89 40 yr. old male; CC profound weakness this morning. Mild weakness; generalized malaise & mild nausea x 2 days. Arrival to ED with severe, bilateral weakness lower extremities greater than upper, lower extremity numbness, tingling & nausea. PMH: Small MI 3 weeks ago; also diagnosed with HTN &

hypercholesterolemia. Meds: Enalapril 20 mg BID / metoprolol 50 mg BID / pravastatin 20 mg daily/ ASA 81 mg daily/ clopidogrel 75 mg daily VS: 154/83; P 67; RR 20; T0 36.3 C PE: Unremarkable except mild abdominal tenderness Labs: Na+ 127(↓)/ Cl- 94(↓)/ BUN 31(↑)/Glu 95/ K+ 7.2(↑↑) / HC03 15 / SrCr 1.5(↑) EKG: Peaked T-Waves →? Remove K +or shift it intracellular What is the problem? HYPERkalemia – 91, 93

HYPERkalemia (> 5 mEq/L) Goals - 91 Monitoring - 93 Parameter Frequency Range 1. Cardiac stabilization 1. K+ 1. q 2-4 hr. 1. > 3.5 mEq/L < 5 mEq/L 2. K+ shift into ICF 2. EKG 2. Continuous 2. Convert to NSR 3. Remove K+ from body 3. EKG 3. Continuous 3. Resolve V-Fib; V-Tach 4. Find cause / correct 4. Weakness 4. q 1 hr. 4. Minimal to none 5. BP 5. q 1 hr. x 2 5. < 50 mg/dL

NSR = Normal Sinus Rhythm / ICF = Intracellular Fluid

HYPERkalemia Treatment - 92 Medication Dose / Route Onset Duration Notes

1. Ca Gluconate 1. 1 gm IVP over 2 min 1. 1-3 min 20-60 min Stabilize cardiac tissue 2. Insulin Regular 2. 10 units IVP over 2 min 2. 10-20 min 2-4 hr. Shift K+ into cell Regular Insulin Know blood glucose – if not, give Dextrose 50 gms. 3. Albuterol Neb. 3. 10-20 mg / NaCl 4 ml 3. 20-30 min 2-4 hr. 4. Na Bicarb 4. 50-100 mEq IVP over 5 min 4. < 30 min 1-2 hr. Short duration; Na+, volume load ↑ 5. Na Polystyrene 5. 15-30 gm. PO 5. 2 hr. (PO) Eliminate K+ from body 30-60 gm (PR) 1 hr. (PR) 6. Furosemide 6. 20-40 mg IVP 6. 30-60 min Eliminate K+ from body 7. Hemodialysis Eliminate K+ from body

To eliminate 5-6, need functioning kidneys to be able to tolerate fluid shift.

22│Renal


CALCIUM Calcium-Phosphate Regulation – 95 • Regulators of Ca++ retention / excretion

1. Calcitriol 2. PTH

• Overview of Ca++-Phos Regulation 1. GI tract, kidneys & bones involved in Ca++ regulation

Calcium Forms – 96 • Ca++ in plasma

1. is in ionized form 2. 45 % in ionized form (physiologically active form) 3. 45 % bound to proteins (10 albumin) 4. 10 % complexed with anions (citrate; sulfate; phosphate)

• Estimating physiologic ionized Ca++with hypoalbuminemia → Measure TOTAL calcium which = bound Ca++ If albumin ↓ → TOTAL calcium may be ↓ → use Ca++ corrected formula to determine value: [Ca++] corrected = [Ca++] measured + [0.8 (4 – Albumin)]

HYPERcalcemia (Ca++ > 10.5 mg/dL or ionized Ca++ > 2.7 mmol/L) - 97 http://www.medscape.com/viewarticle/702842

HYPERcalcemia– Etiologies - 97 ↑ GI Absorption ↑ Bone Losses ↓ Bone Mineralization ↓Urinary Excretion

1. Milk-alkali syndrome 1. ↑ net bone resorption 1. ↑ PTH 1. Thiazide diuretics 2. Elevated Calcitriol •↑ PTH 2. Aluminum toxicity 2. ↑ Calcitriol • Vitamin D Excess A. HYPERparathyroidism 3. ↑ PTH A. Excess intake • Malignancy B. Granulomatous Diseases A. Osteolytic metastases •↑ PTH B. PTHrP secreting tumor • HYPOphosphatemia 2. ↑ bone turnover • Paget’s disease of bone • HYPERthyroidism

HYPERcalcemia – Goals, Treatment Options, Monitoring

Goals - 98 TX Options - 99 Monitoring - 100 Parameter Frequency Range 1. Determine cause 1. Asymptomatic 1. Ionized Ca++ Q 4-6 hr. 1.12-1.3 mmol/L 2. Prevent/treat • Hydration 2. Mag++ Q 4-6 hr. 1.5-2 mEq/L

severe symptoms • Ambulation 3. QT (EKG) Baseline 360-440 msec 3. Prevent inducing 2. Severe Acute 4. Twitching Q 1 hr. Minimal / none

HYPOcalcemia •NS 200-300 ml/hr. 5. Fluid intake Q 1 hr. In = Out Can pt. tolerate? Hypoalbuminemic – order ionized Ca++ 3. Severe non-acute •Bisphosphonate • Calcitonin • Glucocorticoid

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http://www.medscape.com/viewarticle/702842


CALCIUM

HYPERcalcemia Treatment – 99 Degree ↑ HYPERcalcemia Intermittent Dosing Continuous Infusion Mild (asymptomatic) NS 1. 100-300 ml/hr. Severe (acute) NS 1. 200-300 ml/hr. Furosemide 40-100 mg IVP Q 1-4 hrs. Prevents volume excess Helps excrete Ca++ Severe (non-acute) Bisphosphonate 1. Zoledronic acid 4 mg IV over 15 minutes 2. Pamidronate 60 mg IV over 2 hrs. 3. Calcitonin + Bisphosphonates in severe cases. 4 units/kg SQ – effects seen in as little as 2 hrs. post administration.

24│Renal


CALCIUM

HYPOcalcemia Causes – Ca++ ↓ 8.5 mEq - 101 ↓ G.I. absorption ↓ bone resorption/ ↑ mineralization ↑ Urinary excretion 1. Poor Ca++ intake 1. ↓ PTH (AKA HYPOparathyroidism) 1. Low PTH (s/p thyroidectomy; 2. Impaired Ca++ absorption 2. PTH resistance (pseudo HYPOparathyroidism) s/p I131 treatment; autoimmune • Vitamin D deficiency 3. Vitamin D deficiency / ↓ calcitriol HYPOparathyroidism. • ↓ Vitamin D conversion 4. Hungry bones syndrome 2. PTH resistance to calcitriol 5. Osteoblastic metastases 3. Vitamin D deficiency / low

calcitriol

HYPOcalcemia –Goals, Treatment Options, Monitoring Goals - 102 TX Options - 102 Monitoring Parameters - 104 Parameter Frequency Range 1. Determine cause 1. Asymptomatic 1. Ionized Ca++ q 2-4 hr. 1.12-1.3 mmol/L

& treat • PO Ca++ 2. Albumin Once 2.5-4 gm/dL 2. Prevent/treat 2. Severe, 3. Mag++ q 4-6 hr. 1.5-2 mEq/L

severe symptoms Symptomatic: 4. QT (EKG) Baseline 360-440 sec. 3. Prevent inducing • IV replacement 5. Twitching Q 1 hr. Minimal / none

HYPERcalcemia 3. HYPOcalcemia + Vit. D Deficiency: • Due to Anticonvulsant: Ergocalciferol 50,000 IU daily •Due to CKD: 1,25 dihydroxy Vit. D3 or Vit. D2 Analog Calcium is modestly absorbed PO

HYP0calcemia Treatment – 103

Degree of ↑ HYPOcalcemia Calcium Salt Intermittent Dosing Continuous Infusion Mild (asymptomatic) Gluconate 1-2 gm/ IVPB/100 ml D5W over 1 hr. Severe (symptomatic) Gluconate 3 gm. IVPB over 10 min. Severe (symptomatic; refractory) Gluconate 0.8-0.15 mEq/min. Gluconate – less damage if extravasation occurs Chloride – Delivers > elemental Ca++ but more necrotic to tissues if extravasation occurs; only use in ACLS

25│Renal


PHOSPHATE (Intracellular Ion)

HYPERphosphatemia Causes - 106 ↑ GI Intake ↓ Urinary excretion Cell lysis 1. Fleets phosphorus soda 1. Renal failure 1. Rhabdomyolysis

Provides endogenous 2. Low PTH (HYPOparathyroidism) 2. Tumor lysis syndrome phosphate • S/P thyroidectomy

• S/P I131 treatment for Graves’ disease or thyroid cancer

• Autoimmune HYPOparathyroidism Phosphate is an intracellular ion

HYPERphosphatemia GOALS & TREATMENT - 108

Goals - 107 Treatment – 107, 108 Medication Initial DOSE ( w. meals) Max DOSE 1. ID/correct cause 1. Calcium acetate 2 tab. TID 4 tabs. w. meals 2. Normalize level 2. Calcium carbonate 1-2 gms TID 7 gm. / day 3. Avoid/resolve S/S 3. Aluminum hydroxide 1-2 tab. TID/QID, HS 3-6 tab. q 4 hr. 4. Maintain Ca/Phos 4. Mag ++ hydroxide 1-2 tab. TID 2-4 tab. QID, HS

product < 55 mg2/dL2 to 5. Sevelamer 800-1600 mg TID 4 gm. TID prevent stone formation.

In HYPERphosphatemia, Al+3 & Mag+2 can accumulate Most often treat with Ca+2 salts & Sevelamer

HYPOphosphatemia Causes - 109

↓ GI Absorption ↓ Bone Resorption/ ↑ Urinary Excretion Internal Redistribution* ↑ Bone Mineralization (due to stim. of glycolysis) 1. ↓ Intake 1. Vit. D deficiency / low 1. ↑ PTH i.e. 10 1. Refeeding syndrome**

Rare in isolation calcitriol HYPERparathyroidism 2. During DKA treatment*** 2. Diarrhea/malabsorption 2. Hungry bones 2. Vit. D deficiency / low 3. Phosphate binders **** syndrome calcitriol 3. Osteoblastic mets. 3. Fanconi syndrome * Due to acute stimulation of glycolysis. Also occurs with enteral feeding. **i.e. starvation; anorexia; alcoholism ***DKA - diabetic ketoacidosis; HYPERglycemic- HYPERosmolar syndrome→ redistribution occurs →

HYPERphosphatemia can occur **** Calcium acetate, Al & Mg containing antacids.

HYPOphosphatemia – Goals, Treatment - 110

Goals (questions to answer) Treatment Mild – PO Supplementation Severe – IV Replacement 1. Symptomatic? 1. Milk – 1 cup QID 1. < 0.5 → 0.5 mmol/kg (IBW) 2. Defect magnitude? 2. Neutraphos 1-2 pkts. 3-4 x/ day 2. 0.5-1 → 0.25 mmol/kg (IBW) 3. Cause? 3. Fleets Phospha-Soda 5 ml BID 3. 1.1-2.4 → 0.15 mmol/kg (IBW) IV → K+; Na+ salts → must consider contribution to body Think of K+ amount in 15 mmol increments → i.e. per dose Potassium Phosphate → there may be an institutional limit on amount / dose given.

IBW Estimated ideal body weight in (kg) http://www.manuelsweb.com/IBW.htm Males: IBW = 50 kg + 2.3 kg x inches over 5 feet. → i.e. 5’2” → multiply: 2.3 x 2 Females: IBW = 45.5 kg + 2.3 kg x inches over 5 feet.

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http://www.manuelsweb.com/IBW.htm


MAGNESIUM Magnesium - 113 • Magnesium - 2nd most abundant cation in muscle. • 2nd most abundant intracellular cation → important

1. muscle integrity 2. action potential in use of muscle mass

• Concentration 1.5-2.4 mg/dL 1. renal important system to keep Mag++ in check

• Role 1. Important cofactor in biochemical reactions

• Homeostasis 1. 10 renal

HYPERmagnesemia > 0.24 mg/dL - 114

Signs / Symptoms Treatment 1. N/V 1. D/C supplements 2. Deep tendon reflex loss → classic symptom 2. Ca++ IV – 1 gm. over 5-10 min.

3. HYPOtension Repeat until symptoms resolve. 4. Bradycardia 5. EKG Δs

HYPOmagnesemia < 1.5 mg/dL Causes - 115 Treatment Goals - 116 Treatment - 116 1. Alcoholism 1. Treat cause 1. PO options – poor absorption 2. Excess GI losses 2. Avoid/resolve S/S • Mag oxide 3. Infection 3. Normalize level • Mag Citrate 4. Malnutrition 4. Avoid Mag ++ access 2. IV distributes into tissue slowly 5. Medications • 50 % excreted in urine 6. Renal loss • Mild-Moderate 1.2-1.5 7. Sepsis A. Dose: 0.5 mEq/kg 8. Surgery • Severe < 1.2 A. 1 mEq/kg Magnesium important to cardiovascular function. 8 mEq = 1 gm. Premix = 4 gm. dose

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fluid & electrolyte disorder -...

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