Yasser Gebril Inpatient Pharmacy
POTASSIUM CHLORIDE
Learning Objectives
Importance of Potassium Chloride
Potassium Chloride Toxicity
Pharmacokinetics Role of Potassium in the Human Body Epidemiology Causes of Hyperkalemia Diagnosis of Hyperkalemia Treatment of Hyperkalemia
The Need for KCl Guidelines JACHO Recommendation UK Guidelines SSH Potassium Chloride Dosing Guidelines ISMP Recommendations
Hospital Administration Physician and P&T Committee Nursing Units and Pharmacy
Importance of Potassium Chloride 1. Potassium is the primary intracellular ion in the 2. 3. 4. 5.
human body. The normal plasma potassium concentration range is 3.5 to 5 mEq/L. Potassium regulates many biochemical processes in the body, and is a key ion for electrical action potentials across cellular membranes. Potassium chloride is the preferred potassium supplement for the most common causes of hypokalemia. Hyperkalemia commonly results in patients with acute or chronic kidney disease.
Pharmacokinetics Potassium is the most abundant cation in the body, with
estimated total body stores of 3,000 to 4,000 mEq, 98% of this amount is contained within the intracellular compartment, and the remaining 2% is distributed within the extracellular compartment. The Na+-K+-ATPase pump located in the cell membrane is
responsible for the compartmentalization of potassium. This pump is an active transport system that maintains increased
intracellular stores of potassium by transporting sodium out of the cell and potassium into the cell at a ratio of 3:2. Consequently the pump maintains a higher concentration of
potassium inside the cell.
Pharmacokinetics The normal serum concentration range for potassium is 3.5 to 5.0
mEq/L, whereas the intracellular potassium concentration is usually about 140 mEq/L. Approximately 70% of the intracellular potassium is located in
skeletal muscle; the remaining 30% is located in the liver and red blood cells. Extracellular potassium is distributed throughout the serum and
interstitial space. Potassium is dynamic in that it is constantly moving between the
intracellular and extracellular compartments according to the body’s needs. Thus the serum potassium concentration alone does not
accurately reflect the total body potassium content.
Role of Potassium Chloride Potassium has many physiologic functions within cells, including
protein and glycogen synthesis and cellular metabolism and growth. It is also a determinant of the electrical action potential across the cell membrane. The ratio of the intracellular to extracellular potassium concentration is the major determinant of the resting membrane potential across the cell membrane. Thus the resting membrane potential is greatly affected by variations in extracellular potassium concentration. Serum potassium concentrations outside the normal range can have disastrous effects on neuromuscular activity, in particular cardiac conduction. Hypo- and hyperkalemia are both associated with potentially fatal cardiac arrhythmias, along with other neuromuscular disturbances.
Potassium Chloride Toxicity Hyperkalemia: Hyperkalemia is defined as a serum potassium concentration greater than 5.5 mEq/L.
It can be further classified according to its
severity: Mild (serum potassium 5.5 to 6 mEq/L). Moderate (6.1 to 6.9 mEq/L); and Severe hyperkalemia (>7 mEq/L).
Epidemiology Hyperkalemia is much less common than
hypokalemia. The incidence of hyperkalemia in hospitalized patients has been estimated to be 1.4% to 10%. Most cases of hypokalemia are the result of overcorrection of hypokalemia with potassium supplements. Severe hyperkalemia occurs more commonly in elderly patients with renal insufficiency who receive potassium supplementation.
Causes of Hyperkalemia 1. Increased potassium intake 2. Decreased potassium excretion 3. Tubular unresponsiveness to aldosterone. 4. Redistribution of potassium into the
extracellular space.
Diagnosis of Hyperkalemia Clinical Presentation Of Hyperkalemia General Related to the effects of excessive potassium on
neuromuscular, cardiac, and smooth muscle cell function.
Symptoms Frequently asymptomatic; however, the patient may
complain of heart palpitations or skipped heartbeats.
Signs ECG changes
Laboratory Tests Serum potassium concentration >5.5 mEq/L.
Treatment of Hyperkalemia DESIRED OUTCOME The goals of therapy for the treatment of hyperkalemia are: 1. 2. 3.
to antagonize adverse cardiac effects Reverse any symptoms that may be present, and to Return the serum and total body stores of potassium to normal.
Severe hyperkalemia (>7 mEq/L) or moderate hyperkalemia (6.1 to 6.9 mEq/L), when associated with clinical symptoms or electrocardiographic changes, requires immediate treatment. Initial treatment of hyperkalemia is focused on antagonism of the membrane actions of hyperkalemia (Using Calcium). Secondarily, one should attempt to decrease extracellular potassium concentration by promoting its intracellular movement (e.g., with glucose, insulin, β2-receptor agonists, or sodium bicarbonate). Finally, removal of potassium from the body by hemodialysis and/or cationexchange resins may need to be implemented. The underlying cause of hyperkalemia should be identified and reversed, and exogenous potassium must be withheld.
Treatment Algorithm for Hyperkalemia Abnormal ECG? (peaked twaves, widened QRS complex)
Yes
Administer Calcium gluconate
No Continuous ECG monitoring
Yes Hyperglycemia?
No Administer insulin & glucose
Consider albuterol
Consider bicarbonate if acidotic
Give exchange resin or consider dialysis
Follow potassium level every two hours until <5.5 mEq/L
Give insulin & Follow blood sugar
Therapeutic Alternatives for the Management of Hyperkalemia Medication
Dose
Route
Onset/Duration Acuity of Action
Mechanism of action
Expected Result
Calcium
1gm (1 Vial) IV over 5-10 min 1-2 min/10-30 min
Acute
Raises cardiac Threshold potential
Reverses cardiographic effects
Furosemide
20-40 mg
IV
5-15 min/4-6 hours
Acute
Inhibits renal N+ reabsorption
Increased urinary K+ Loss
Regular insulin
5-10 units
IV- SubQ
30 min/2-6 hours
Acute
Stimulates K+ intracellular uptake
Intracellular K+ redistribution
Dextrose 10%
1000 ml
IV over 1-2 hour 30 min/2-6 hour
Acute Stimulates insulin release
Intracellular K+ redistribution
Dextrose 50%
50 ml
IV over 5 min
Acute Stimulates insulin release
Intracellular K+ redistribution
Sodium Bicarb
50-100mEq IV over 2-5 min 30 min/2-6 hour
Acute Raises serum pH
Intracellular K+ redistribution
Albuterol
10-20 mg
Nebulizer 10min 30 min/1-2 hour
Acute
Hemodialysis
4 hours
NA
Immediate/Variable
Acute Removal from plasma
Kayexalate
15-60 gm
Oral or rectal
1 hour/variable
30 min/2-6 hour
Non
Stimulates K+ intracellular uptake
Resin exchanges Na+ for K+
Intracellular K+ redistribution Increased K+ elimination Increased K+ elimination
Why Do We Need To Have Guidelines? The following incidents with potassium chloride have been reported to ISMP Canada: 1.
10 mL potassium chloride (KCl) concentrate was administered direct IV when the intended action was to flush an intravenous line with 10 mL 0.9% sodium chloride. Result: patient Death.
2.
10 mL KCl concentrate was used to reconstitute a drug for parenteral administration when the intended diluent was sterile water. Result: Near miss (error was noted before administration).
3.
10 mL KCl concentrate was administered as a bolus injection by a health care professional who was unaware that KCl concentrate cannot be given as a bolus but must be diluted in a minibag and given as an infusion. Result: patient Death.
4.
A one-liter IV solution was prepared with 400 mEq of potassium chloride and although it was administered at a very low rate, the incident was felt to be a near miss because of the potential for accidental overdose.(error was noted during administration).
5.
IV solutions containing KCl were administered as a fluid replacement in a patient requiring several liters of fluid in a short time frame. Result: hyperkalemia, Death
JCAHO Recommendations JCAHO high priority national patient safety
goals includes: “Improve the Safety of Using High-Alert Medications” with the recommendations to: 1. Remove concentrate electrolytes (including, but not limited to, potassium chloride, potassium phosphates, sodium chloride >0.9 percent) from patient care units; and 2. Standardize and limit the number of drug concentrations available in the organization
United Kingdome the National Patient Safety Agency established by the
National Health Service (NHS ) issued a Patient Safety Alert in July 2002 to all Chief Executives of National Health Service Trusts and Primary Care Trusts in Britain. It required actions in all centers of the National Health Service to reduce the potential for patient injury with the use of potassium chloride by October 31, 2002. In the Alert, one of the strategies suggested that: “Pharmacists should also remove potassium chloride concentrate from wards and clinical areas, use commercially prepared diluted potassium solution where possible, and store potassium chloride concentrate in a separate locked cupboard.”
SSH Potassium Dosing Guidelines SAAD SPECIALIST HOSPITAL
POTASSIUM DOSING GUIDELINES Developed by the DIPC; Pharmacy Department November 2006 Approved by the P&T 2006 This Guideline serves as suggested
I
Parenteral 1. Indicated for patients unable to tolerate or receive oral replacement, patients with urine output > 1 ml/kg/hour and serum Cr < 1 mg/dl, and for patients with renal impairmen. 2. All patients require cardiac monitoring for concentrated Potassium doses Concentrations >80 mEq/l or doses > 0.2 mEq/kg/hour
Parenteral Status
Route
Moderate to Severe Deficiency:
IV Bolus:
K+ less than or equal 2.5mmol/L with or without symptoms e.g. cardiac arrythmias or conduction disturbances, respiratory muscle weakness, paralaysis OR patient on digoxin)
Adult: Central line: 20mEq/100mL over 1 hour Peripheral line: 10mEq/100mL over 1 hour Pediatrics: 0.5-1mEq/kg over 2 hour (same as adult concentration) Fluid restriction Central line:40mEq/100mL over 1 hour
ECG monitoring for rates >5 mEq/hour, frequent potassium levels, and acid-base balance are recommended
Mild to Moderate Deficiency: K+ more than or equal 2.5mmol/L
II.
Concentration and Rate
IV infusion: Adult and Pediatrics: Peripheral line: usual 20-40mEq/L infused at max rate of 10mEq/hour Central line: usual 20-60mEq/L infused at max rate of 20mEq/hr Adult: Central line: 20mEq/100mL over 1 hour Peripheral line: 10mEq/100mL over 1 hour Pediatrics: 0.5-1mEq/kg over 2 hour (same as adult concentration) Fluid restriction Central line:40mEq/100mL over 1 hour
Oral:
Oral Status
Dosage
K+ more than or equal 2.5mmol/L
Adult: 60-80 mEq/day plus additional amounts if needed. (Check serum K+ levels daily) Pediatrics: 1-2 mEq/kg initially, then as needed based on frequently obtained lab values. If deficits are severe or ongoing losses are great, I.V. route should be considered
Preventative Therapy: (e.g. Receiving Amphotericin B, Diuretics, Severe diarrhea, etc)
Adult: 20-40 mEq/day in 1-2 divided doses. Pediatrics: 1-2 mEq/kg/day in 1-2 divided doses
Mild to Moderate Deficiency:
ISMP KCl Safety Recommendations Hospital Administration Physicians And P&T Committee Nursing Units and Pharmacy
1- Hospital Administration Create a high-level multidisciplinary team with a
mandate to: Reduce the error potential of potassium chloride (KCl). Define an implementation strategy (including
timelines). Provide regular updates to the hospital board’s Quality & Risk Management Committee. Include discussion of KCl injury and preventive system safeguards during orientation programs for nurses, physicians, and pharmacists and locum staff
Physicians and P&T committee 1. Pharmacy and Therapeutics Committee to develop
clear guidelines for the use of KCl, including:
Use of oral, instead of IV, KCl whenever clinically feasible. Standardization of prescribing practices to match available
premixed KCl solutions. Maximum concentration of KCl allowable in an IV solution. Proper mixing to avoid pooling. Maximum hourly and daily limits of KCl that a patient may receive. Maximum infusion rate. Requirements for infusion rate and patient monitoring. Evaluation of need and/or feasibility of automatic substitution policy.
Physicians and P&T committee’ Cont. 2. Identify that orders such as “KCl 40 mEq IV now”
or “give KCl 20 mEq IV bolus” should be considered incomplete and unacceptable. Orders require instructions for dilution and infusion rate. 3. If it is deemed necessary that concentrated KCl products be available in a critical care area, create policies to restrict and safeguard their use. Consider a locked cupboard and/or a double sign-out procedure for obtaining the concentrated product
NURSING UNIT Have each patient care unit, program, department, and clinic
undertake a review by physicians, nurses and pharmacists with the following aims: Identify if concentrated KCl products are in patient care areas. Plan and organize actions to remove concentrated KCl products from patient care areas. Have standardized premixed KCl IV solutions available in adequate quantities. Store premixed KCl solutions separately from plain IV solutions. If concentrated KCl products must be available in a critical care area, follow P&T policies regarding access, e.g., locked cupboard and/or a double sign-out procedure for obtaining the product.
Pharmacy 1.
Work with the appropriate department(s), e.g., Stores and Nursing, to arrange for storage and distribution of premixed KCl IV solutions.
2.
Consider purchasing only the 40 mEq /20 mL size concentrate (not 20 mEq/10 mL size) to minimize the chance of mix-up with other commonly used products such as 10 mL sterile water and 10 mL normal saline.
3.
Pharmacy should prepare any nonstandard solutions that are deemed absolutely necessary but are unavailable commercially in a premixed format.
4.
Minibag products containing KCl should be dispensed and controlled by the pharmacy only.
5.
Add an auxiliary fluorescent warning label to the KCl concentrate product at the time of receipt of the drug into inventory in the pharmacy.
6.
Add auxiliary warning label to premixed minibags containing KCl, providing the recommended route of administration (e.g., “central line only”) and the recommended duration of infusion (e.g., “infuse over at least 1 hour”).
7.
Have pharmacists intervene when nonstandard orders for IV solutions with KCl are prescribed. Prescribing practices must take into consideration the premixed KCl IV solutions that are available.
8.
Choose a designated area for storing concentrated KCl products in the pharmacy to reduce the likelihood of substitution errors.
THINK SAFE THINK TWICE DOUBLE CHECK
THANK YOU