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Fluids and Electrolytes

Salman Bin AbdulAziz University

College Of Pharmacy

Therapeutics I PHCL 416

Ahmed A AlAmer

PharmD

A 65-year-old man with a 3-day history of temperature to 102°F, lethargy, and productive cough is hospitalized for community-acquired pneumonia.

• His medical history includes hypertension and coronary artery disease.

• His vital signs include HR 104 beats/minute, BP 112/68 mm Hg, and temperature 101.4°F. His weight is 80 kg, decreased skin turgor , urine output 10 mL/hour, BUN 16, Cr 1.7 mg/dL, and WBC 10.4. Other laboratory values are normal.

• What do you think this patient has ?

I. Volume overload

II. Volume depletion

III. non

Case I

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• Subjective and objective for this patient are?

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A 65-year-old man with a 3-day history of temperature to 102°F, lethargy, and productive cough is hospitalized for community-acquired pneumonia.

• His medical history includes hypertension and coronary artery disease.

• His vital signs include HR 104 beats/minute, BP 112/68 mm Hg, and temperature 101.4°F. His weight is 80 kg, decreased skin turgor , urine output 10 mL/hour, BUN 16, Cr 1.7 mg/dL, and WBC 10.4. Other laboratory values are normal.

• What do you think this patient has ?

I. Volume overload

II. Volume depletion

III. non

Case I

• Signs (like HR and BP) in patient with Intravascular Volume Depletion improved after a 500- to 1000-mL fluid bolus

(T/F)

• Tachycardia is the earliest sign of volume depletion

(T/F)

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• What’s the goal of therapy in this patient ?

Restore intravascular volume and prevent organ hypoperfusion.

Fluid resuscitation is indicated for patients with signs or symptoms of intravascular volume depletion.

• Which one of the following is most appropriate for this patient at this time?

A. Furosemide 40 mg intravenously.

B. Albumin 25% intravenously over 60 minutes.

C. Hetastarch 6% 500 mL intravenously over 60 minutes.

D. . 500- to 1000-mL fluid bolus (NS, LR)

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Fluid resuscitation Maintenance Intravenous Fluids

A. IV fluids are infused rapidly, preferably through a central venous catheter. B . Intravenous fluids are administered as a 500- to 1000-mL bolus, after which the patient is reevaluated; this process is continued as long as signs and symptoms of intravascular volume depletion are improving.

Fluid resuscitation Maintenance Intravenous Fluids

Crystalloids (0.9% NaCl or LR) are recommended for fluid resuscitation. Colloids ? are generally not superior to crystalloids and are associated with a considerably higher cost. Give examples of colloids ?

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Fluid resuscitation Maintenance Intravenous Fluids

Maintenance intravenous fluids are indicated in patients who are unable to tolerate oral fluids. The goal of maintenance intravenous fluids ? prevent dehydration and maintain a normal fluid and electrolyte balance.

Fluid resuscitation Maintenance Intravenous Fluids

Continuous infusion through a peripheral or central intravenous catheter

typical maintenance intravenous fluid is D5W with 0.45% NaCl plus 20–40 mEq of KCl/L. The KCl content can be adjusted for the individual patient.

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• Which one of the following is most appropriate for this patient at this time?

A. Furosemide 40 mg intravenously.

B. Albumin 25% intravenously over 60 minutes.

C. Hetastarch 6% 500 mL intravenously over 60 minutes.

D. 500- to 1000-mL fluid bolus (NS, LR)

• After 2 days of appropriate antibiotic treatment, the patient in question 1 has WBC of 9, and he is afebrile. His BP is 135/85 mm Hg, and his urine output is now 45 mL/hour. His albumin is 3.2, BUN 14, and Cr 1.4 mg/dL. All other laboratory values are normal. His appetite is still poor, and he is not taking adequate fluids. He has peripheral intravenous access.

• Which one of the following is most appropriate to initiate?

A. Peripheral PN to infuse at 110 mL/hour.

B. Albumin 5% 500 mL intravenously over 60 minutes.

C. D5W/0.45% NaCl plus KCl 20 mEq/L to infuse at 110 mL/hour.

D. LR solution to infuse at 110 mL/hour.

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• After 2 days of appropriate antibiotic treatment, the patient in question 1 has WBC of 9, and he is afebrile. His BP is 135/85 mm Hg, and his urine output is now 45 mL/hour. His albumin is 3.2, BUN 14, and Cr 1.4 mg/dL. All other laboratory values are normal. His appetite is still poor, and he is not taking adequate fluids. He has peripheral intravenous access.

• Which one of the following is most appropriate to initiate?

A. Peripheral PN to infuse at 110 mL/hour.

B. Albumin 5% 500 mL intravenously over 60 minutes.

C. D5W/0.45% NaCl plus KCl 20 mEq/L to infuse at 110 mL/hour.

D. LR solution to infuse at 110 mL/hour. Sign and symptoms stopped ( no need Resuscitation)

Need for maintenance iv fluid

Fluids and Electrolytes II

Salman Bin AbdulAziz University

College Of Pharmacy

Therapeutics I PHCL 416

Ahmed A AlAmer

PharmD

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• A 72-year-old woman , weight 60 kg , with a history of hypertension has after starting hydrochlorothiazide she experiences dizziness, fatigue, and nausea.

• 3 weeks earlier. Her serum Na+ is 116 mEq/L K+ is 4 mEq/L, BP is 86/50 mm Hg, and HR is 122 beats/minute.

• This patient has

This patient has

I. Hypernatremia, hypervolemia

II. Hyponatremia , hypovolemia

III. Hyponatremia, hypervolemia

Sodium 135–145 mEq/L

Potassium 3.5–5.0 mEq/L

This patient has (tachycardia Hypotension )… hypovolemia Serum Na+ … low (hyponatremia)

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• A 72-year-old woman , weight 60 kg , with a history of hypertension , has after starting hydrochlorothiazide she experiences dizziness, fatigue, and nausea.

• 3 weeks earlier. Her serum Na+ is 116 mEq/L K+ is 4 mEq/L, BP is 86/50 mm Hg, and HR is 122 beats/minute. U Na+ >40 mEq/L

• This patient has

Symptoms of hyponatremia appears after what level ?

I. < 130 mEq/L

II. <140 mEq/L

III. <120 mEq/L

Sodium 135–145 mEq/L

Potassium 3.5–5.0 mEq/L

Mild

Moderate Severe

• A 72-year-old woman , weight 60 kg , with a history of hypertension has after starting hydrochlorothiazide she experiences dizziness, fatigue, and nausea.

• 3 weeks earlier. Her serum Na+ is 116 mEq/L K+ is 4 mEq/L, BP is 86/50 mm Hg, and HR is 122 beats/minute. U Na+ >40 mEq/L

• This patient has

The cause of hyponatremia is HCT ( hydrochlorothiazide) ? ( T/F)

Sodium 135–145 mEq/L

Potassium 3.5–5.0 mEq/L

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• A 72-year-old woman , weight 60 kg , with a history of hypertension has after starting hydrochlorothiazide she experiences dizziness, fatigue, and nausea.

• 3 weeks earlier. Her serum Na+ is 116 mEq/L K+ is 4 mEq/L, BP is 86/50 mm Hg, and HR is 122 beats/minute.

A. 0.9% NaCl infused at 100 mL/hour.

B. 0.9% NaCl 500-mL bolus.

C. 3% NaCl infused at 60 mL/hour.

D. 23.4% NaCl 30-mL bolus as needed.

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• A 72-year-old woman , weight 60 kg , with a history of hypertension has after starting hydrochlorothiazide she experiences dizziness, fatigue, and nausea.

• 3 weeks earlier. Her serum Na+ is 116 mEq/L K+ is 4 mEq/L, BP is 86/50 mm Hg, and HR is 122 beats/minute. U Na+ >40 mEq/L

A. 0.9% NaCl infused at 100 mL/hour.

B. 0.9% NaCl 500-mL bolus.

C. 3% NaCl infused at 60 mL/hour.

D. 23.4% NaCl 30-mL bolus as needed.

Hypovolemia (bolus ) = fluid resuscitation

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MCQ

Correction the underlying cause in this patient means ?

I. Discontinue hydrochlorothiazide

II. Start patient on loop diuretics

III. Give patient BB (beta blocker) to manage his HR

• For the patient described above, which one of the following is the best treatment goal for the first 24 hours in correcting her serum Na+ from her initial value of 116 mEq/L? why ?

A. Increase Na+ concentration to 140 mEq/L.

B. Increase Na+ concentration to 132 mEq/L.

C. Increase Na+ concentration to 126 mEq/L.

D. Maintain serum Na+ between 116 mEq/L and 120 mEq/L.

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Rapid correction of hyponatremia can cause permanent neurologic damage. (To prevent central pontine myelinolysis)

• For the patient described above, which one of the following is the best treatment goal for the first 24 hours in correcting her serum Na+ from her initial value of 116 mEq/L? why ?

A. Increase Na+ concentration to 140 mEq/L.

B. Increase Na+ concentration to 132 mEq/L.

C. Increase Na+ concentration to 126 mEq/L.

D. Maintain serum Na+ between 116 mEq/L and 120 mEq/L.

Why? …write down the answer

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• Correction limit in mild chronic hyponatremia is ?

• Correction limit in moderate acute hyponatremia is ?

• Correction limit in severe acute hyponatremia ?

How to calculate infusion rate for NS?

Initial rate = desired serum [Na+] increase per hour (mEq/h) x patient weight (kg) (example: Na+ by 1 mEq/L/h in 70 kg patient = 70 mL/h infusion,

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change in serum sodium = (infusion sodium concentration [mmol/L] - serum sodium concentration [mmol/L]) / (total body water + 1)

to estimate effect of 1 L of any saline infusion on serum sodium

sodium concentrations of various infusates 5% sodium chloride in water = 855 mmol/L 3% sodium chloride in water = 513 mmol/L 0.9% sodium chloride in water = 154 mmol/L Ringer's lactate solution = 130 mmol/L 0.45% sodium chloride in water = 77 mmol/L 0.2% sodium chloride in 5% dextrose in water = 34 mmol/L 5% dextrose in water = 0 mmol/L

total body water (in L) = weight (in kg) x (age/gender-specific fraction of body weight) 0.6 in children and adult nonelderly men 0.5 in adult nonelderly women and elderly men 0.45 in elderly women

Fluids and Electrolytes III

Salman Bin AbdulAziz University

College Of Pharmacy

Therapeutics I PHCL 416

Ahmed A AlAmer

PharmD

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A 40-year-old man has been admitted to the hospital after several days of vomiting and diarrhea. In the emergency department, he had several runs of nonsustained ventricular tachycardia.

His plasma K+ on admission was 2.8 mEq/L. After receiving 200 mEq of potassium chloride (KCl) infused over 24 hours, his repeat K+ is 3.2 mEq/L, and he continues to have runs of ventricular tachycardia.

Other laboratory values include Na+ 143 mEq/L, magnesium 1.1 mEq/L, phosphorus 3 mg/dL, Ca++ 9 mg/dL, and ionized Ca++ 1.1 mmol/L.

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• What information (signs, symptoms, laboratory values) indicates the presence and severity of the electrolyte abnormalities? ( SOAP )

S

vomiting and diarrhea

O

he had several runs of nonsustained ventricular tachycardia.

plasma K+ on admission was 2.8 mEq/L.

include Na+ 143 mEq/L, magnesium 1.1 mEq/L, phosphorus 3 mg/dL, Ca++ 9 mg/dL, and ionized Ca++ 1.1 mmol/L.

A

Based on clinical presentation and lab values

This patient has hypokalemia that’s resistant to the conventional treatment

P ?

• The cause of hypokalemia in this case ?

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Causes of hypokalemia

a. Reduced intake seldom causes hypokalemia because renal excretion is minimized

because of increased renal tubular absorption.

b. Increased shift of K+ into cells can occur with the following:

i. Increased pH

ii. Insulin or a carbohydrate load

iii. β2-Receptor stimulation caused by stress-induced epinephrine release or

administration of a β-agonist (e.g., albuterol, dobutamine)

iv. Hypothermia

c. Increased GI losses of K+ can occur with vomiting, diarrhea, intestinal fistula or enteral tube drainage, and chronic laxative abuse.

d. Increased urinary losses can occur with mineralocorticoid excess and diuretic use (e.g., loop and thiazide type). ( common cause )

e. Hypomagnesemia is commonly associated with hypokalemia caused by increased renal loss of K+; correction of plasma K+ requires simultaneous correction of serum magnesium.

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Complete

• Regarding symptoms of mild hypokalemia ( 3.5-3 mEq/L) ) patient is ……………..

( symptomatic / asymtomatic )

• Regarding symptoms of moderate hypokalemia ( 3- 2.5 mEq/L) ) patient may complain of symptoms include ……………..

• Patient with severe hypokalemia ( <2.5 mEq/L) can have ………(signs ,symptoms )

ANSWER cramping, weakness, malaise, and myalgias

ANSWER electrocardiogram (ECG) changes Musculoskeletal: Cramping and impaired muscle contraction.

MCQ

What type of hyperkalemia this patient has ?

I. Mild hypokalemia

II. Moderate hypokalemia

III. Severe hypokalemia Why? Check the level and ECG

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Treatment of hyperkalemia

Patients without EKG changes or symptoms

Patients with EKG changes or symptoms

Oral supplementation (eg KCl) .

Oral Or IV ( Severe or with ECG changes )

Whenever possible, potassium supplementation should be administered by mouth

Treatment of hyperkalemia

Patients without EKG changes or symptoms

Oral supplementation (eg KCl) .

(doses greater than 60 mEq should be divided to avoid GI adverse effects)

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Treatment of hyperkalemia

Patients without EKG changes or symptoms

Oral supplementation (eg KCl) .

Potassium Cl- is the preferred salt in patients with concurrent metabolic alkalosis because these patients typically lose Cl- through diuretics or GI loss. Other salts ? All the following can be taken orally K Chloride most common used + metabolic alkalosis K Phosphate patient with hypophosphatemia K Bicarbonate. metabolic acidosis. Potassium acetate

IV K+ salts Potassium acetate …metabolic acidosis Potassium chloride

T/F

• IV K supplement is adminstired as bolus ( IV push) • Doses more than 60 mEq of oral potassium can be administered as one dose why? To avoid gastric erosion • To avoid irritation, no more than about 60 mEq/L should be administered

through a peripheral vein. • Recommended infusion rate is 10–20 mEq/hour to a maximum of 40

mEq/hour.

• Patients who receive K+ at rates faster than 10–20 mEq/hour should be monitored using a continuous EKG.

(F)

(F)

(T)

(T)

(T)

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Which one of the following suggestions is best to treat this patient’s hypokalemia? A. Administer KCl 20 mEq intravenously over 1 hour each × 4 doses and

recheck K+.

B. Administer magnesium sulfate as a 2-g slow intravenous infusion. C. Administer K+ phosphate 15 mmol intravenously over 4 hours. D. Administer Ca++ gluconate 2 g intravenously over 5 minutes.

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Which one of the following suggestions is best to treat this patient’s hypokalemia? A. Administer KCl 20 mEq intravenously over 1 hour each × 4 doses and

recheck K+.

B. Administer magnesium sulfate as a 2-g slow intravenous infusion. C. Administer K+ phosphate 15 mmol intravenously over 4 hours. D. Administer Ca++ gluconate 2 g intravenously over 5 minutes.