Potassium Replacement Prescribing, Monitoring and ...



Standard Operating ProcedurePotassium Replacement Prescribing, Monitoring and Administration - AdultPurposeTo ensure the safe prescribing, monitoring and administration of oral and intravenous potassium (K+) to adult patients at Canberra Hospital and Health Services.ScopeAll approved Health Directorate staff working within their scope of practice that prescribe, monitor, administer or advise on the use of oral or intravenous potassium in adult patients at Canberra Hospital and Health Services.Use of this procedure assumes underlying causes have been determined and are being rmation on the use of potassium acetate and potassium dihydrogen phosphate is not included in this standard operating procedure. Consult you clinical pharmacist for information regarding the use of these.Procedure1. High-risk MedicationThe administration of intravenous (IV) potassium is a potentially dangerous procedure:Errors in calculation or admixture of concentrated potassium containing solutions can result in serious adverse reactions and even death;IV bolus administration of concentrated potassium can be lethal;When high concentrations are used, even minor divergence from the recommended rate of administration can be cardiotoxic.Preparing concentrated potassium solutions for IV infusion administration, as opposed to the use of pre-mixed bags, has the following risks:Errors in calculation of potassium additive;Inadequate mixing of potassium and infusion solution, leading to pooling of the potassium additive and inadvertent potassium bolus.See sections 4 and 5 for available oral and pre-mixed IV bags.Additional potassium chloride MUST NEVER be added to a pre-mix bag as this will affect their osmolarity, and render them unable to be administered via a peripheral line. 2. Determination of Potassium Replacement Requirements in Patients with a Potassium DeficitTotal body potassium deficit should be used to determine route and rate of potassium replacement. Aim to replace 25% of the total body deficit in the first 6 hours and 50 – 75% of the total body deficit in 24 hours.Total body potassium deficit = serum potassium deficit + ongoing losses (refer to tables below). Serum Potassium (mmol/L)Serum potassium Deficit (mmol)+Ongoing lossesAmount of Potassium Per Litre Loss3200Urine20mmol/Lurine2.5300Diuretics75-100mmol/L urine2400Alkalosis75-100mmol/L urine1.5 (near lethal)400+Gut loss (diarrhoea, vomiting)40mmol/L GIT lossPancreatic or small bowel fistula100mmol/L fluid lossOnce the degree of deficit has been determined, refer to the following table to decide upon the most appropriate route and rate of potassium replacement.Category of Total Body Deficit or Serum Potassium (if no losses)RoutePotassium DosageMonitoring RequiredMild Deficit: 150mmol total body potassium deficit ORSerum K+: 3 – 3.5 mmol/L OralPotassium chloride slow release tablets: 2 (16 mmol K+) PO bd OR,Potassium chloride oral mixture 10%: 15mL (20 mmol K+) PO bd OR,Potassium chloride effervescent tablets (Chlorvescent?): 1 (14 mmol K+) PO bdDaily serum potassium ECG not requiredModerate Deficit: 200 – 300mmol total body potassium deficit OR Serum K+: 2.5 – 3 mmol/L Oral(preferred)orIVPotassium chloride slow release tablets: 3 (24 mmol K+) PO tds OR, Potassium chloride oral mixture 10%: 20mL (21.6 mmol K+) PO tds OR,Potassium chloride effervescent tablets (Chlorvescent?): 2 (28 mmol K+) PO tdsIV Peripheral Line (rate not to exceed 10mmol/hr)30mmol/1000 mL pre-mix bag OR,10mmol/100mL isotonic sodium chloride pre-mix bag*IV Central Line (rate not to exceed 20mmol/hr)30 mmol/1000mL pre-mix bag OR,10mmol/100mL isotonic sodium chloride pre-mix bagDaily serum potassiumECG not required unless the patient is at risk of arrhythmiasSevere Deficit: 400mmol total body potassium deficit OR Serum K+: 2 – 2.5 mmol/L Consider admission to the Intensive Care Unit (ICU)OralandIVPotassium chloride slow release tablets: 3 (24 mmol K+) PO tds OR,Potassium chloride oral mixture 10%: 20 mL (21.6 mmol K+) PO tds OR,Potassium chloride effervescent tablets (Chlorvescent?): 2 (28 mmol K+) PO tdsIV Peripheral Line (rate not to exceed 10mmol/hr)30mmol/1000 mL pre-mix bag OR,10mmol/100mL isotonic sodium chloride pre-mix bag*IV Central Line (rate not to exceed 20mmol/hr without continuous ECG monitoring but may be increased to 40mmol/hr with continuous ECG monitoring)30 mmol/1000mL pre-mix bag OR,10mmol/100mL isotonic sodium chloride pre-mix bagSerum potassium every 6 – 12 hoursECGCritical Deficit: > 400mmol total body potassium deficit OR Serum K+: 1.5 – 2 mmol/L Admit to the Intensive Care UnitOral(if possible)andIVPotassium chloride slow release tablets: 3 (24 mmol K+) PO tds OR,Potassium chloride oral mixture 10%: 20 mL (21.6 mmol K+) PO tds OR,Potassium chloride effervescent tablets (Chlorvescent?): 2 (28 mmol K+) PO tdsIV Peripheral Line ( rate not to exceed 10mmol/hr)30mmol/1000 mL pre-mix bag OR, 10mmol/100mL isotonic sodium chloride pre-mix bag* IV Central Line (rate not to exceed 20mmol/hr without continuous ECG monitoring but may be increased to 40mmol/hr with continuous ECG monitoring)30 mmol/1000mL pre-mix bag OR,10mmol/100mL isotonic sodium chloride pre-mix bagSerum potassium every 6 – 12 hoursECG* Where ‘10mmol K+ in 100mL N/S or normal saline’ is prescribed, the 10mmol/100mL isotonic 0.29% sodium chloride pre-mix bag can be used as it is an isotonic equivalent solution.3. Normal Daily Potassium Requirements for Patients who are Nil by MouthFor an adult patient of average weight (70kg), the typical daily potassium requirements are approximately 1mmol K+ / kg i.e. a 70kg patient would require 70 mmol of K+ per day.For obese patients, potassium requirements should be based on lean body weight.4. Available Oral Potassium SupplementsThe oral potassium supplements available at The Canberra Hospital are detailed in the table below.ProductPotassium concentrationBrand NamesNotesPotassium chloride oral mixture20mmol (1.5g) in 15mLPotassium chloride Oral Mixture 10% w/v?Potassium chloride slow release tablets8mmol (600mg) per tabletSlow K?, Span K?, Duro K?Potassium chloride – potassium carbonate – potassium bicarbonate effervescent tablets14mmol per tabletChlorvescent?Must be dissolved in 100-150mL waterPotassium citrate products are also available but are indicated for the prevention of kidney stones and increasing urine pH. 5. Available Pre-mixed Potassium Bags for Intravenous InfusionThe pre-mixed potassium bags for intravenous infusion available at Canberra Hospital & Health Services are detailed in the table below.Potassium ConcentrationVolumeNotesOrder From10mmol potassium in 0.29% sodium chloride100mL isotonic preparationThe isotonic formulations contain a different concentration of sodium chloride to the other pre-mix bags. This enables safe peripheral administration. The same concentration cannot be made with normal saline (sodium chloride 0.9%) bags. Pharmacy20mmol potassium in 0.45% sodium chloride and 5% glucose1000mLPharmacy30mmol potassium in 0.18% sodium chloride and 4% glucose1000mLSupply Services (Mitchell)30mmol potassium in 5% glucose1000mL Supply Services (Mitchell)30mmol potassium in Hartmann’s solution1000mL Supply Services (Mitchell)30mmol potassium in 0.9% sodium chloride1000mL Supply Services (Mitchell)10mmol potassium in 0.45% sodium chloride and 2.5% glucose500mL Supply Services (Mitchell)6. Prescribing and Preparation of Potassium for Intravenous Infusion in Concentrations Unavailable as a Pre-mix BagPrescribers should order potassium available in pre-mixed bags to avoid errors in calculations and/or mixing unless there is a clear clinical need. If there is a clear clinical need, the concentration prescribed for peripheral line access must not exceed 40mmol/1000mL of compatible fluid (refer to the Australian Injectable Drugs Handbook) due to the increased risk of thrombophlebitis.If a patient is fluid restricted ALWAYS consider giving potassium via the oral route. If a non-standard bag is required during the hours of 830am and 430pm, the pharmacy department will prepare the bag in the IV room. Contact the pharmacy department IV room via ext 42633.Outside of these hours, non-standard bags are to be prepared by the nursing staff. Additional potassium chloride MUST NEVER be added to a pre-mix bag as this will affect their osmolarity, and render them unable to be administered via a peripheral line. Plasmalyte? solution does not have published stability data available that supports the addition of extra potassium chloride; as such the pharmacy department IV room are unable to make potassium chloride additions to Plasmalyte?. Potassium 10mmol/10mL ampoules are restricted to critical care areas only.If a potassium infusion is prepared on a ward it should be prepared according to the guidelines set out in the Australian Injectable Drugs Handbook including thorough mixing (invert 10 times) to prevent pooling of the potassium additive.EvaluationOutcome MeasuresAdult patients in The Canberra Hospital and Health Services who require oral or intravenous potassium replacement are safely and appropriately managed.MethodAll incidents related to this procedure are reported via the Clinical Incident Reporting System Riskman & Staff Accident Incident Reporting (SAIR). Incidents are reviewed and corrective actions are reported via relevant departments in line with continuous quality improvement processes.ReferencesAustralian Injectable Drugs Handbook 4th edn. Potassium chloride.Australian Medicines Handbook: Blood and Electrolytes: Drugs for Electrolyte Imbalances: Drugs for Potassium Imbalance (online) [accessed 19/08/2011]MIMS Online Slow K; Span K; Duro K;Chlorvescent. Full Product Information (online) [accessed 17/08/2011]Queensland Health Safe Medication Practice Unit: Fluid and Electrolyte Guidelines Working Party. Prescribing Intravenous Fluids and Electrolytes. 3rd edn. 2008.Disclaimer: This document has been developed by Health Directorate, Division of Medicine, specifically for its own use. Use of this document and any reliance on the information contained therein by any third party is at his or her own risk and Health Directorate assumes no responsibility whatsoever. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download