Calcium Chloride + Citric Acid + Sodium Chloride

Usage

This combination of calcium chloride, citric acid, and sodium chloride is primarily used in regional citrate anticoagulation (RCA) during continuous renal replacement therapy (CRRT). It is not typically prescribed as a medication for other conditions outside of this specific context. It falls under the pharmacological classifications of anticoagulant and electrolyte replenisher.

The mechanism of action involves citrate chelating ionized calcium in the blood, thereby interrupting the coagulation cascade and preventing clotting within the CRRT circuit. The sodium chloride helps maintain osmotic balance and electrolyte levels, while the citric acid component contributes to the overall buffering of the solution.

Alternate Names

This combination does not have a specific generic name, as it is formulated specifically for RCA in CRRT settings. It may be referred to as “citrate anticoagulant solution” or “RCA solution”. There are no widely recognized brand names for this specific mixture, though proprietary solutions used for CRRT with RCA may incorporate these components.

How It Works

Pharmacodynamics: Citrate binds to ionized calcium, rendering it unavailable for the coagulation cascade. This prevents clot formation within the CRRT circuit. Sodium chloride maintains isotonicity and provides electrolytes. Citric acid buffers the solution, contributing to acid-base balance.

Pharmacokinetics: Citrate is metabolized by the liver to bicarbonate. Calcium is filtered out during CRRT, necessitating supplementation. Sodium and chloride are routinely monitored and adjusted during CRRT.

Mode of Action: Citrate acts by chelating ionized calcium. This chelation directly inhibits the calcium-dependent steps of the coagulation cascade.

Elimination Pathways: Citrate is primarily metabolized in the liver. Calcium is removed by the CRRT circuit. Sodium and chloride are primarily eliminated renally, but removal is affected by the CRRT parameters.

Dosage

Dosage for this combination is specific to the CRRT protocol and patient parameters. There is no standard dosage regimen outside of CRRT.

Standard Dosage

Standard dosing is individualized and based on the patient’s CRRT prescription and their calcium, electrolyte, and acid-base status. Dosage is adjusted based on frequent monitoring of blood ionized calcium, total calcium, bicarbonate, pH, other electrolytes and acid–base parameters.

Clinical Use Cases

This combination is used in CRRT during:

• Intubation: Not usually required.
• Surgical Procedures: Not usually required.
• Mechanical Ventilation: Not usually required.
• Intensive Care Unit (ICU) Use: Specifically during CRRT.
• Emergency Situations: Not usually indicated.

Side Effects

Common Side Effects

• Metabolic alkalosis
• Hypocalcemia
• Electrolyte imbalances (hypomagnesemia, hypokalemia)

Rare but Serious Side Effects

• Citrate accumulation (in patients with liver failure or impaired metabolism) leading to severe hypocalcemia and metabolic acidosis.

Adverse Drug Reactions (ADR)

• Severe hypocalcemia leading to tetany, seizures, or cardiac arrhythmias.

Contraindications

• Liver failure (relative contraindication, requires careful monitoring).
• Severe shock (relative contraindication, due to impaired citrate metabolism).
• Hypersensitivity to any component (rare).

Drug Interactions

• Calcium supplements: May decrease anticoagulant effect of citrate.
• Medications containing calcium: May counteract the anticoagulant effect of citrate.
• Sodium bicarbonate: May increase risk of metabolic alkalosis.

Pregnancy and Breastfeeding

Data on the use of this combination during pregnancy and lactation are limited. Use only if clearly needed and under close monitoring.

Drug Profile Summary

• Mechanism of Action: Citrate chelates ionized calcium, inhibiting coagulation.
• Side Effects: Hypocalcemia, metabolic alkalosis, electrolyte imbalances.
• Contraindications: Liver failure, severe shock.
• Drug Interactions: Calcium supplements, sodium bicarbonate.
• Pregnancy & Breastfeeding: Limited data; use with caution.
• Dosage: Individualized based on CRRT prescription and patient status.
• Monitoring Parameters: Ionized calcium, total calcium, bicarbonate, pH, other electrolytes.

Precautions

• General Precautions: Careful monitoring of electrolytes, acid-base balance, and ionized calcium during CRRT.
• Specific Populations: Monitor patients with renal or hepatic impairment closely.
• Lifestyle Considerations: Not applicable.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for Calcium Chloride + Citric Acid + Sodium Chloride during CRRT?

A: There is no fixed dosage. It is titrated based on the patient’s individual needs and CRRT prescription, with continuous monitoring of ionized calcium, total calcium, pH, and other electrolytes.

Q2: How does citrate prevent clotting in CRRT?

A: Citrate chelates ionized calcium, a crucial component of the coagulation cascade, thus preventing clot formation.

Q3: What are the common side effects of this combination in CRRT?

A: The most common side effects are hypocalcemia, metabolic alkalosis, and other electrolyte disturbances (hypomagnesemia, hypokalemia).

Q4: What is citrate lock-in syndrome?

A: While this term is often used related to CRRT, it is outdated. It reflects a condition resulting from citrate toxicity during CRRT which has since been better understood. It referred to citrate accumulation, causing cardiovascular instability and a severely increased total/ionized calcium ratio. The recommended practice is now to use calcium ratio to assess anticoagulation quality and prevent complications.

Q5: Are there any contraindications to using this solution?

A: Liver failure and severe shock are relative contraindications because they can impair citrate metabolism.

Q6: How should calcium be administered during CRRT with citrate anticoagulation?

A: Calcium is usually given as calcium chloride or calcium gluconate intravenously, with the dose and rate titrated based on the patient’s ionized calcium levels. It may also be administered in the dialysate itself as part of pre-defined mixtures of electrolytes used in CRRT.

Q7: What are the key monitoring parameters during CRRT with citrate anticoagulation?

A: Closely monitor ionized calcium, total calcium, bicarbonate, pH, and other electrolyte levels (sodium, potassium, magnesium, phosphate).

Q8: What should be done if citrate accumulates during CRRT?

A: Reduce or stop the citrate infusion, correct metabolic acidosis with bicarbonate, and consider alternative anticoagulation methods.

Q9: Can this solution be used outside of CRRT?

A: This specific combination is not generally used outside of the context of CRRT.

Q10: What happens to the citrate administered during CRRT?

A: The citrate is metabolized in the liver to bicarbonate.