INFUSION PUMPS

Fluid container

Drip chamber

Roller Clamp

Basic Infusion System

• Flow by gravity

• Flow controlled by roller clamp

• Difficult to set and control infusion rate

Infusion Pumps

What are they?• Usually electrically powered infusion devices

What do they do?• Use pumping action to infuse fluids, medication or

nutrients into patient• Suitable for intravenous, subcutaneous, enteral and

epidural infusions

Infusion Pumps

Why are they used?• To provide accurate and controllable flow over a prescribed

period or on demand

What are they used for?Wide range of drugs and therapies including• Chemotherapy• Pain management• Total parental nutrition• Anaesthesia/sedation• Etc. etc.

Infusion Pumps

TWO BASIC TYPES

• Syringe Pumps

• Volumetric Pumps

Syringe Pump

Syringe Pumps

• Generally used for low volume, low flow rate infusions

• Good short term accuracy• Long start up time at low flow rates

– Prime and purge line before connecting to patient

• Alarms: End/near end of infusion; drive disengaged, occlusion, battery low

• Specialised syringe pumps for ambulatory use, PCA, sedation, insulin etc

Volumetric Pumps

Latch

Cam followers (fingers)

Pressure sensor

Air in line detector

Volumetric Pumps

• Preferred for medium and high flow rates and large volumes

• Generally not suitable for rates < 5ml/h• Variable short term accuracy• Alarms: Latch/door open, set out,

occlusion, battery low, air-in-line• Specialised volumetric pumps for

ambulatory use, epidural infusions etc.

Infusion Pump Incidents

700 incidents/year reported to MHRA, including 10 deaths

20% Device related (e.g. design, failures etc)27% User error53% Not established (majority user error)

Many incidents not reported e.g. 6 Trusts, 321 incidents

Reporting Incidents

• All incidents should be reported on a Clinical Adverse Patient Incident Form

• Aim is to reduce risk in future, not to apportion blame

• Where an infusion pump is involved, the pump and its disposables must be retained, and Clinical Physics informed.

What Goes Wrong?

Medication ErrorsMedication Errors

• Prescription

• Preparation of infusion solution

• Calculation of rate of infusion

What Goes Wrong?

Medication ErrorsMedication Errors

• Prescription

• Preparation of infusion solution

• Calculation of rate of infusion

• Setting up infusion pump/unfamiliarity

If you accidentally use a BLUE 1hr pump instead of a GREEN 24 hour pump, you will deliver the drug at 24 times the intended rate.

What Goes Wrong?

Medication ErrorsMedication Errors

• Prescription• Preparation of infusion solution• Calculation of rate of infusion• Setting up infusion pump/unfamiliarity

Do not use a model you have not been trained and are deemed competent to use

What goes wrong?

Free flow by gravity/siphoningFree flow by gravity/siphoning

- What is it: Uncontrolled fluid flow by gravity from syringe or bag.

- Has resulted in a significant number of fatalities, none yet in North Glasgow.

Free Flow in Volumetric Pumps

If fluid container is a few inches above heart level, free flow by gravity can occur if:

• Pump latch/door open. Always close roller clamp before removing set from pump.

Latch closed

Clamp open

Latch open

Clamp closed

Free Flow in Volumetric Pumps

If fluid container is a few inches above heart level, free flow by gravity can occur if:

• Pump latch/door opened. Always close roller clamp before removing set from pump.

• Infusion set not correctly loaded

Free Flow in Volumetric Pumps

If fluid container is a few inches above heart level, free flow by gravity can occur if:

• Pump latch/door opened. Always close roller clamp before removing set from pump.

• Infusion set not correctly loaded• Damage to set resulting in an air leak

Free Flow in Syringe Pumps

If pump is a few inches above heart level, free flow by gravity can occur if:

1. Syringe not correctly located and secured to pump. Check syringe barrel clamp, barrel flange and plunger located correctly and secured.

Free Flow in Syringe Pumps

If pump is a few inches above heart level, free flow by gravity can occur if:

1. Syringe not correctly located and secured to pump. Check syringe barrel clamp, barrel flange and plunger located correctly and secured

2. Syringe removed from pump. Always close clamp first.

Free Flow in Syringe Pumps

If pump is a few inches above heart level, free flow by gravity can occur if:

1. Syringe not correctly located and secured to pump. Check syringe barrel clamp, barrel flange and plunger located correctly and secured

2. Syringe removed from pump. Always close clamp first.

3. Air leak caused by crack in syringe, plunger seal leak, loose luer connection, distortion of barrel/plunger.

To prevent free flow

• Never remove syringe or set from pump whilst connected to patient, without closing the clamp first (or checking it is closed)

• Always use a set with an anti free flow device (not available for Alaris/IVAC 59 series)

• Check set or syringe is correctly loaded• Check drip chamber on volumetric pump for

unexpected flow after set loading and during infusion

• Keep syringe pump near to or below infusion site

What Goes Wrong?

Occlusion alarm (all pumps)Occlusion alarm (all pumps)

- Occurs when pump is unable to sustain set flow rate and pressure in line increases

- Caused by partial or complete blockage in delivery tubing (kinked tube, clamp or tap closed) or cannula (clotted off, position changed)

Occlusion Alarm

Time to alarm• Dependent on occlusion pressure level

(usually variable) and flow rate– Low pressure, high flow rate 45 seconds– High pressure, low flow rate 45 minutes

• To reduce time to alarm and bolus size– Use highest flow rate clinically acceptable– Use lowest occlusion pressure setting possible

without causing nuisance alarms– User smaller syringes

Occlusion Alarm

Hazards

• Interruption to therapy– Problem with critical, fast acting drugs e.g.

inotropes

• Post occlusion bolus

Tissuing (Extravasation)Extravasation occurs when fluid that should be delivered intravenously is inadvertently delivered into a tissue space.

Tissuing

• Cannot be detected by infusion pumps– Usually little or no increase in pressure

• Secure and dress the catheter for stability

• Check IV site frequently for tenderness, skin tightening, cooling and blanching

What Goes Wrong?

Air-in-lineAir-in-line

• Volumetric pumps have a risk of air being delivered due to poor priming of set, upstream leak or pumping action drawing air out of solution

• Volumetric pumps have either a mechanism for preventing pumping of air or an air-in-line detector & alarm

Air-in-line Alarm

Hazards

• Nuisance alarms

• Interruption to therapy– Problem with critical, fast acting drugs e.g.

inotropes– Recent fatality in North Glasgow

What Goes Wrong?

Tampering by patients/visitors/carersTampering by patients/visitors/carers

1. Keylock

2. Lock box

Ambulatory (portable)

What Goes Wrong?

Equipment FaultsEquipment Faults• Often occur as a result of damage due to fluid

ingress or being dropped/knocked• Always return damaged pumps to Clinical

Physics – never use or attempt to repair• Infusion devices very reliable, faults rarely

result in adverse incidents

Training

• This presentation and demonstrations to follow are a general introduction ONLY

• Before using any infusion device you MUST have received specific training for that model and be signed off as competent – over 50 models in North Glasgow

• Otherwise DO NOT USE