Calcium gluconate Intravenous for Adults

Who can administer

May be administered by registered competent doctor or nurse/midwife

Important information

• Do NOT administer through same line as solutions containing phosphate, bicarbonate or sulphates
• Must not be administered simultaneously with ceftriaxone (even via a different site or infusion line). May be given sequentially, provided the infusion lines are thoroughly flushed between infusions or different infusion sites are used ^{(ref 5)}
• AVOID rapid administration: may cause hot flushes, peripheral vasodilation, hypotension, nausea and vomiting, cardiac arrhythmias and arrest

Available preparations

• Calcium gluconate 10% (2.25mmol) per 10ml plastic ampoule (Braun) - unlicensed

Reconstitution

Already in solution

Infusion fluids

Sodium chloride 0.9% or Glucose 5%

Methods of intravenous administration

Intravenous infusion (administer using an electronically controlled infusion device) (preferred method)

• Add required dose to a suitable volume of infusion fluid and administer as per 'Dose' overleaf
• If a 50ml infusion volume is used, the residual volume in the infusion line must be flushed through at the same rate to avoid significant underdosing

Slow intravenous injection (in emergency- eg severe acute hypocalcaemia, cardiac resus)^{(ref 1)}

• Administer very slowly (at least 5 minutes for 10ml) ^{(ref 1)}
• Administer via a central line or large peripheral vein ^{(ref 1)}
• There is a risk of arrythmias if the drug is given too quickly
• If injection is administered too rapidly, nausea, vomiting, hot flushes, sweating, hypotension and vasomotor collapse, possibly fatal, may occur

Dose in adults

Severe acute hypocalcaemia/hypocalcaemic tetany ^{(ref 2)}

• Give 10 to 20ml of injection solution (2.25 to 4.5mmol calcium) with plasma calcium and ECG monitoring - each 10ml over five minutes ^{(ref 1)}(risk of arrythmias if given too rapidly)
• This can be repeated as required or, if only temporary improvement, can be followed by an infusion of 22.5mmol (100ml injection solution) added to 900ml Sodium chloride 0.9% or Glucose 5%. Initial rate 50ml/hour, adjusted according to response ^{(ref 2)} (use electronically controlled infusion device)
• Measure serum calcium levels every four to six hours ^{(ref 4,5)}
• Seek urgent Endocrinology team input

Hyperkalaemia with ECG changes or if K+ greater than 6mmol/L- myocardial protection ^{(ref 3)}

• Give 30ml of injection solution (6.75mmol calcium), preferably diluted in 50 to 100ml infusion fluid over 10 minutes
• Give over 30 minutes if on digoxin
• Doses may be repeated if no ECG improvement within 5 to 10 minutes of first dose completed

As an antidote to magnesium in severe hypermagnesaemia ^{(ref 5)}

• Doses similar to those used in severe acute hypocalcaemia (see above) have been used

Post-parathyroidectomy- where corrected calcium is 1.9mmol/L or less. High dose regimen ^{(ref 6,7)} - administer using an electronically controlled infusion device

• Should be used only under the guidance of the Endocrinology Consult Service
• This guideline is only used if severe symptoms and corrected Calcium 1.9mmol/L or less
• Preferably- administer in HDU/ICU setting. If no bed available in ICU/HDU, can administer on a ward with telemetry monitoring
• Can cause tissue necrosis, so administer via central line or large patent IV access
• Calculate the dose of Calcium gluconate 10% in mL = 1.7x patients weight in kg, and dilute as follows:
• Withdraw this volume of fluid from a 1,000ml infusion bag of Sodium chloride 0.9% or Glucose 5% and replace with the calculated dose/volume of calcium gluconate 10% injection solution
• Administer over four to six hours ^{(ref 6,7)}. The rate of infusion may be reduced if the calcium levels improve
• Example - patient weighs 72kg, dose is 1.7x72 = 122.4ml calcium gluconate 10%. Withdraw 122ml from a 1,000mL bag, and add 122ml Calcium Gluconate 10% injection (i.e. over 12 ampoules) solution back into the bag
• Monitoring- see over

Cardiac Resuscitation

• As per resuscitation guidelines

Renal impairment

• Prolonged infusions or repeated doses should be avoided

Monitoring

• Monitor U&E's four to six hourly ^{(ref 4,5)}
• Monitor heart rate, blood pressure ^{(ref 1)}
• Check magnesium and phosphate at baseline ^{(ref 8)}
• Post-parathyroidectomy- High dose regimen - monitor ionised calcium every two hours. Telemetry monitoring required. ^{(ref 7)}
• The infusion site must be monitored to ensure extravasation injury has not occurred
• ECG monitoring is required for intravenous injection as there is a risk of arrythmias if given too quickly

Further information

• Do not give with phosphates, bicarbonates or sulphates
• Patient should remain lying down for a short time after administration of intravenous calcium
• 2 milliequivalent (mEq) Calcium = 1mmol (mmol) Calcium
• Calcium gluconate 1g is equivalent to 93mg, 4.5mEq, 2.25mmol calcium (ref 1,8)
• Note: GUH use unlicensed plastic ampoules exclusively to avoid aluminium exposure risk which has been associated with glass ampoules.

Storage

Store below 25⁰C

References

1. Injectable medicines administration guide, Medusa, Downloaded 19/01/2024

2. BNF- accessed online via ClinicalKey 19/01/2024

3. GUH guide to hyperkalaemia management (Adults)- December 2023

4. Injectable Drugs guide- accessed via Medicinescomplete 19/01/2024

5. Martindale accessed via Medicinescomplete 14/03/2024

6. Barts Endocrine e-Protocols Calcium disorders and bone. December 2009- accessed online 19/01/2024

7. Dr Marcia Bell, Expert opinion 13th July 2016

8. UptoDate- accessed online 14/03/2024