How to prepare an infusion in a 50 ml syringe pump?

Preparing a 50 mL Syringe Pump Infusion

To prepare an infusion in a 50 mL syringe pump, use sterile technique to draw up the medication into a 50 mL syringe, dilute to the appropriate concentration with compatible diluent (typically 0.9% sodium chloride or D5W), remove all air bubbles by holding the syringe upright and tapping, then load into a dedicated, lockable infusion pump with appropriate labeling.

General Preparation Steps

Equipment Assembly

• Gather a sterile 50 mL syringe, the prescribed medication vial(s), appropriate diluent, needles for drawing up medication (typically 18-20 gauge), and alcohol wipes 1
• Ensure you have a dedicated infusion pump that is lockable, tamperproof, and adjustable with anti-siphon and anti-reflux mechanisms 1
• Use commercially prepared syringes when available to reduce concentration errors 1

Medication Preparation Using Sterile Technique

• Maintain strict sterile technique throughout preparation—either have an assistant hold vials or use single-operator technique keeping one hand sterile 1
• Draw up the prescribed amount of medication from the vial using an appropriately sized needle 1
• Add the compatible diluent to reach the final 50 mL volume, ensuring you achieve the correct concentration for your dosing protocol 1
• Remove all air bubbles by holding the syringe upright and tapping the side to release bubbles to the top, then expel air 1

Common Concentration Examples

For norepinephrine in a 50 mL syringe:

• Add 4 mg norepinephrine to 50 mL D5W (instead of the standard 250 mL) to create a more concentrated solution if needed, though standard concentration uses 250 mL 2
• Alternative: 1 mg in 100 mL saline creates 10 mcg/mL concentration 2

For fortified antibiotics (ophthalmic use):

• Vancomycin 25 mg/mL: Add 20 mL diluent to 500 mg vial 1
• Cefazolin 50 mg/mL: Add 9.2 mL artificial tears to 1 g vial, then dilute further 1

Loading and Administration

Pump Setup

• Load the prepared syringe into the dedicated infusion pump according to manufacturer instructions 3, 4
• Attach appropriate IV tubing with a one-way valve to prevent retrograde flow 1
• Prime the tubing to remove air, using a minimum flush of 0.9% sodium chloride at 10 mL/h through a separate dedicated line 1
• Label the infusion line with appropriate medication identification (e.g., ISO-standard grey label for lidocaine) 1

Safety Checks Before Starting

• Verify the correct concentration by double-checking your calculation 5
• Ensure the pump is set to the correct flow rate for the prescribed dose 1, 4
• Set both a fixed rate and fixed upper rate limit on the pump 1
• Confirm the syringe is properly secured and there are no leaks 3

Critical Safety Considerations

Route of Administration

• Use central venous access whenever possible for vasopressors like norepinephrine to minimize extravasation risk 2, 6
• If peripheral access must be used temporarily, monitor the site closely every 15 minutes initially 1, 2

Monitoring Requirements

• Monitor continuously with ECG and pulse oximetry during initial infusion 1
• Check blood pressure every 5-15 minutes during titration 1, 2
• Watch for signs of extravasation (pain, swelling, blanching at IV site) 2, 6

Extravasation Management

• If extravasation occurs with vasopressors, immediately infiltrate phentolamine 5-10 mg diluted in 10-15 mL saline at the site 2, 6
• For pediatric patients, use phentolamine 0.1-0.2 mg/kg up to 10 mg 2, 7

Common Pitfalls to Avoid

• Never mix adrenergic drugs with sodium bicarbonate or alkaline solutions in the IV line, as they become inactivated 6
• Avoid frequent changes in infusion rate—adjustments should be made by senior clinicians only 1
• Do not accidentally flush or bolus the line, especially with vasoactive medications 7
• Ensure adequate volume resuscitation before starting vasopressors to prevent severe organ hypoperfusion 2, 6
• Protect light-sensitive medications by covering the syringe with protective foil 7