IV CANNULATION AND FIXATION INFUSION PUMP

Intravenous Cannulation

Pediatric intravenous cannulation is an integral part of modern medicine and

is practiced in virtually every health care setting. Venous access allows the

sampling of blood, as well as administration of fluids, medications, parenteral

nutrition, chemotherapy, and blood products.

This topic describes the placement of an intravenous catheter in an upper

extremity of a pediatric patient. A similar technique can be used for placement of

intravenous catheters in different anatomical sites.

Indications

Indications for pediatric intravenous cannulation include the following:

Repeated blood sampling

Intravenous fluid administration

Intravenous medication administration

Intravenous chemotherapy administration

Intravenous nutritional support

Intravenous blood or blood products administration

Intravenous administration of radiological contrast agents (eg, computed

tomography, magnetic resonance imaging, nuclear imaging)

Contraindications

No absolute contraindications exist for pediatric intravenous cannulation.

Peripheral venous access in an injured, infected, or burned extremity should be

avoided if possible.

Vesicant solutions can cause blistering and tissue necrosis if they leak into the

tissue. Irritant solutions (pH < 5, pH >9, or osmolarity >600 mOsm/L, including

sclerosing solutions, some chemotherapeutic agents, and vasopressors) also are

more safely infused into a central vein. Therefore, these solutions should only be

given through a peripheral vein in emergency situations or when a central venous

access is not readily available.

Technical Considerations

Best Practices

In an emergency situation or when patients are expected to require large

volumes infused over a short period of time, the largest gauge and shortest catheter

that is likely to fit the chosen vein should be used. The catheter chosen should

always be slightly smaller than the vein.

Veins have a three-layered wall composed of an internal endothelium

surrounded by a thin layer of muscle fibers, which is surrounded by a layer of

connective tissue. Venous valves encourage unidirectional flow of blood, prevent

pooling of blood in the dependent portions of the extremities, and can impede the

passage of a catheter through and into a vein. Venous valves are more numerous

just distal to the points were tributaries join larger veins and in the lower

extremities.

Veins with high internal pressure become engorged and are easier to access.

The use of venous tourniquets, dependent positioning, pumping via muscle

contraction, and the local application of heat or nitroglycerin ointment can

contribute to venous engorgement.

The superficial veins of the upper extremities are preferred to those of the

lower extremities for peripheral venous access because they interfere less with

patient mobility and pose a lower risk for phlebitis.[3] It is easier to insert a venous

catheter where two tributaries merge and form a Y-shape. It also is recommended

to choose a straight portion of a vein to minimize the chance of hitting valves.

The scalp veins are easily accessed in infants. They can be engorged by placing a

rubber band around the patient’s head at the forehead level.

Complication Prevention

Use of an anesthetic cream 30 minutes prior to insertion attempt and/or

subcutaneous infiltration of an anesthetic solution should be used prior to

peripheral intravenous insertion whenever possible.

Collapse of the vein, inadequate skin traction, incorrect positioning, and

incorrect angle of penetration can all lead to a failed attempt. Either attempt

insertion at a different site or, if you believe that the selected vein should be

accessible, withdraw the venous access device to just beneath the skin and

reattempt to insert.

If blood stops flowing into the flashback chamber, vein collapse,

venospasm, needle hub position against a venous valve, or penetration of the

posterior wall of the vein might be the cause. Observation of a developing

hematoma will necessitate removal of the catheter. Release and then reapply the

venous tourniquet and attempt to gently stroke the vein to engorge it with blood

and release venospasm. Finally, attempt to withdraw the needle a few millimeters

to move it away from a valve.

If there is difficulty advancing the catheter over the needle and into the vein,

failure to release the catheter from the needle before insertion, encountering a

venous valve, removing the needle too far with the catheter being too soft to

advance into the vein, poor skin traction, or venous collapse can all be the cause.

Release the tourniquet and then reapply it to help engorge the vein. Connect a

syringe with normal saline (0.9%) solution to the hub, then attempt to “float” the

device in place by flushing the catheter and advancing it at the same time.

If there is difficulty flushing after the catheter was placed in a vein, catheter tip

position against a venous wall or a valve, blood clot, or piercing of the venous wall

might be the cause. Observation of a hematoma will necessitate removal of the

catheter. Withdraw the catheter slightly to release it from a wall/valve and attempt

to flush it back in.

Palpate the vein carefully before attempting to insert a venous access device

to ensure that there is no palpable pulse in the vessel. If an accidental arterial

puncture did occur, as evidenced by arterial pulsation of blood out of the catheter,

remove the catheter and apply direct pressure using gauze for at least 10 minutes.

Thrombophlebitis can be caused by either thrombus formation with subsequent

inflammation and/or infection. Pain to the intravenous site of along the path of the

catheter, skin erythema and/or induration, swelling, drainage from the skin

puncture site, or presence of a palpable venous cord are the signs of

thrombophlebitis. Remove the catheter and treat with appropriate antibiotics if you

suspect an infectious etiology.

Regularly and at least daily inspect the site of insertion for signs of

infections. Some sources recommend the routine replacement of peripherally

inserted intravenous catheters every 3-4 days, whereas others suggest that proper

antiseptic technique and at least daily monitoring of the insertion sites may allow

for safe less frequent replacement as long as no signs of phlebitis are present.[4]

Accidental puncture of the median nerve is rare but possible as it is located just

posterior to the basilic vein in the antecubital fossa. Other peripheral nerves might

be accidentally punctured, causing pain and rarely paralysis when other veins are

selected.

Continuous infusion of solutions into a venous access device that extravasated into

the surrounding tissue might result in a compartment syndrome. Make sure to

monitor the site while the transfusion is taking place and use extra caution in

patients who are unable to communicate pain or discomfort. Some infusion pumps

are preset to stop the infusion and sound an audible alert with any increase in

resistance to flow.

Some vesicant and irritant solutions may cause severe soft tissue damage if

they extravasate outside of the vein and into the surrounding tissue.

Periprocedural Care

Patient Education & Consent

Explain the procedure to the patient and/or the patient’s representative and obtain

verbal consent.

Equipment

This topic describes the use of the “over-the-needle” type of intravenous

catheter, in which the catheter is mounted on the needle, as shown in the image

below.

Various sizes of "over-the-needle" intravenous catheters.

This device is available in various gauges, lengths, compositions, and designs.

Gauges range from 16-24 G and lengths range from 25-45 mm (see the image

below).

An "over-the-needle" intravenous catheter.

In general, the smallest gauge of catheter should be selected for the prescribed

therapy to prevent damage to the vessel intima and ensure adequate blood flow

around the catheter in order to reduce the risk of phlebitis.

Necessary equipment includes the following:

Nonsterile gloves

Tourniquet

Antiseptic solution (2% chlorhexidine in 70% isopropyl alcohol)

Local anesthetic solution

1-mL syringe with a 30-G needle

2 × 2 gauze

Venous access device

Vacuum collection tubes and adaptor

Saline or heparin lock

Saline or heparin solution

Transparent dressing

Paper tape

Padded arm board

1/2-inch gauze bandage roll

Equipment is shown in the images below.

Some of the equipment required for intravenous cannulation

.

Some of the equipment required for intravenous cannulation.

Patient Preparation

Anesthesia

Both intradermal injection of a topical anesthetic agent just prior to

intravenous insertion as well as topical application of a local anesthetic cream

about 30 minutes prior to intravenous insertion have been shown to significantly

reduce the pain associated with intravenous catheterization. They should be used

unless in emergent situation.

Positioning

Make sure there is adequate light and that the room is warm enough to

encourage vasodilation. Adjust the height or position of the bed or chair to make

sure you are comfortable and to prevent unnecessary bending.

Make sure the patient is in a comfortable position and place a pillow or a rolled

towel under the patient’s extended arm.

The patient’s skin should be washed with soap and water if visibly dirty.

Because infants and young children are unlikely to cooperate, it is

recommended that an assistant aids in stabilizing the extremity during the

procedure.

Technique

Approach Considerations

Use properly fitted nonsterile gloves and eye protection device to prevent

exposure via accidental blood splashes.

Intravenous Catheter Insertion

Place a venous tourniquet over the patient’s nondominant arm and select a

site for intravenous catheter insertion (see the image below).

Vein palpation for pediatric intravenous cannulation.

The veins of choice for catheterization include the cephalic or basilic veins,

followed by the dorsal hand venous network. For prolonged courses of therapy, it

is recommended, although not always practical, to start distally and move

proximally as distal catheters are replaced. In infants, the dorsal hand and dorsal

foot veins are usually easier to access than the antecubital vein.

If difficulty is encountered in finding an appropriate vein, one of the following

techniques may be used: inspection of the opposite extremity, opening and closing

the fist, gravity (holding the arm down), gentle tapping or stroking of the site, or

applying heat (warm towel/pack).

Ultrasound guidance has been shown to facilitate peripheral venous

placement in emergency department patients with difficult intravenous access and

should be used when appropriate veins are not readily visualized or palpable

Transillumination is another technique that can be used in patients with difficult

intravenous access.

Apply an antiseptic solution such as 2% chlorhexidine solution or 70%

alcohol with friction for 30-60 seconds and allow to air dry for up to 1 minute to

ensure disinfection of the site and to prevent stinging as the needle pierces the skin

(see the image below).

Application of antiseptic solution for pediatric intravenous cannulation.

Once cleaned, do not touch or repalpate the skin.

While the skin is allowed to dry, flush the saline or heparin lock with the

appropriate solution. The syringe may be left attached to the tubing. If blood

sampling via a syringe is planned (as in this illustrated case), you should not flush

the saline/heparin lock, but you may connect an empty syringe to it.

Unless in an emergent situation and if the patient is interested in local

anesthesia, infiltrate 0.5-1 mL of a local anesthetic using a 25- or 30-G needle to

raise a wheal at the site of catheter insertion.

Stabilize the vein using your nondominant hand (thumb) applying traction to

the skin distal to the chosen site of insertion. This will prevent superficial veins

from rolling away from the needle. Stabilization should be maintained throughout

the procedure.

Hold the venous access device in your dominant hand bevel up. This will

ensure smoother catheterization because the sharpest part of the needle will

penetrate the skin first. Release the needle from the catheter and replace it ensuring

the catheter was not damaged or fragmented. This will ensure smooth advancement

once the venous access device is inside the vein.

The angle of the needle entry into the skin will vary according to the device

used and the depth of the vein. Small superficial veins are best accessed using a

small catheter (22-24 G) placed at a 10- to 25-degree angle. Deeper veins should

be accessed with a larger catheter at a 30- to 45-degree angle. See the image below.

Angle of insertion with bevel up for pediatric intravenous cannulation.

Upon entry into the vein, the practitioner might feel a “giving way” sensation and

blood should appear in the chamber of the venous access device (ie, flashback).

See the image below.

Flashback of blood into the venous access device for pediatric intravenous

cannulation.

The angle of the venous access device should be reduced to prevent

puncturing the posterior wall of the vein. It should be advanced gently and

smoothly an additional 2-3 mm into the vein.

If no blood is observed in the flashback chamber, the device should be

withdrawn to just beneath the skin level and another attempt to recatheterize the

vein should take place. Flashback may stop if the device punctured the posterior

wall of the vein or in extremely hypotensive patients. If swelling develops,

withdraw the device, release the tourniquet, and apply direct pressure for 5 minutes

as a hematoma developed.

If venous catheterization is unsuccessful, the needle should never be

reintroduced into the catheter. This could result in catheter fragmentation and

embolism.

While maintaining skin traction with your nondominant hand after the hub

of the venous access device was dropped to the skin, hold the needle grip portion

of the venous access device in place between your dominant thumb and middle

finger, while using your dominant index finger to slide the hub of the catheter over

the needle and into the vein. See the image below.

Sliding the hub of the catheter over the needle and into the vein in pediatric

intravenous cannulation.

You may apply a transparent dressing to the hub at this time in order to stabilize

the venous access device in the vein (see image below).

Securing a venous access device in place using a transparent dressing in pediatric

intravenous cannulation.

While using your nondominant middle finger to apply pressure over the

catheter to prevent blood spill and using holding the hub in place using your

nondominant index and thumb fingers, use your dominant hand to withdraw the

needle and secure it in either its safety cover and/or a dedicated biohazard sharps

container. See the image below.

Using the nondominant hand to secure the venous access device in the vein, while

using the dominant hand to remove and secure the needle.

If blood sampling is needed, use a syringe attached to the saline lock and obtain the

required samples. A Vacutainer adaptor or a syringe can also be directly attached

to the venous access device. Release the tourniquet once the blood sample

obtained. See the image below.

Blood sampling in pediatric intravenous cannulation.

While applying pressure to the catheter to prevent blood spillage and while

continuously stabilizing the hub and wings to the skin as described before,

disconnect the blood sampling adaptor or syringe and securely attach the pre

flushed saline or heparin lock to the hub of the venous access device.

Using the saline or heparin flush syringe, withdraw a small amount of blood to

verify that the catheter is still inside the vein and immediately flush the tubing with

the remainder solution. Slide the plastic tubing lock and continue to lock the

tubing, if such a lock is available. Finish securing the tubing to the skin using tape.

See the image below.

Flushing the venous access device in pediatric intravenous cannulation.

Place a label indicating date, time, and other facility-required information over the

transparent dressing.

Keeping an intravenous line from being pulled out by pediatric patient can be

challenging. The images below show some of the methods for securing such lines.

Securing a pediatric venous access device

.

Securing a pediatric venous access device

.

Securing a pediatric venous access device.

The video below demonstrates an example of pediatric intravenous cannulation

Intravenous Catheter Removal

Stop the infusion solution and disconnect tubing leaving just the

saline/heparin lock tubing connected to the venous access device.

Release the adhesive tape and transparent dressing from the skin.

Withdraw the catheter outside of the vein and apply direct pressure with

gauze for at least 5 minutes.

Inspect the catheter for fragmentation and document in the patient’s chart the

date, time, and reason for catheter removal and the integrity of the catheter

as inspected.

Place a 2 × 2 gauze pad or a cotton ball with a paper tape over the

intravenous insertion site and instruct the patient to continue manual

pressure for 10 more minutes in order to minimize hematoma formation.

An infusion pump infuses fluids, medication or nutrients into

a patient's circulatory system. It is generally used intravenously, although

subcutaneous, arterial and epidural infusions are occasionally used. Infusion pumps

can administer fluids in ways that would be impractically expensive or unreliable if

performed manually by nursing staff. For example, they can administer as little as

0.1 mL per hour injections (too small for a drip), injections every minute,

injections with repeatedboluses requested by the patient, up to maximum number

per hour (e.g. in patient-controlled analgesia), or fluids whose volumes vary by the

time of day

Because they can also produce quite high but controlled pressures, they can

inject controlled amounts of fluids subcutaneously (beneath the skin), or epidurally

(just within the surface of the central nervous system- a very popular local

spinal anesthesia forchildbirth).

Types of infusion

The user interface of pumps usually requests details on the type of infusion

from the technician or nurse that sets them up:

Continuous infusion usually consists of small pulses of infusion, usually

between 500 nanoliters and 10 milliliters, depending on the pump's design, with

the rate of these pulses depending on the programmed infusion speed.

Intermittent infusion has a "high" infusion rate, alternating with a low

programmable infusion rate to keep the cannula open. The timings are

programmable. This mode is often used to administer antibiotics, or other drugs

that can irritate a blood vessel.

Patient-controlled is infusion on-demand, usually with a preprogrammed

ceiling to avoid intoxication. The rate is controlled by a pressure pad or button

that can be activated by the patient. It is the method of choice for patient-

controlled analgesia (PCA), in which repeated small doses

of opioid analgesics are delivered, with the device coded to stop administration

before a dose that may cause hazardous respiratory depression is reached.

Total parenteral nutrition usually requires an infusion curve similar to normal

mealtimes.

Some pumps offer modes in which the amounts can be scaled or controlled based

on the time of day. This allows for circadian cycles which may be required for

certain types of medication.

Types of pump

There are two basic classes of pumps. Large volume pumps can pump

nutrient solutions large enough to feed a patient. Small-volume pumps

infuse hormones, such as insulin, or other medicines, such as opiates.

Within these classes, some pumps are designed to be portable, others are

designed to be used in a hospital, and there are special systems for charity and

battlefield use.

Large-volume pumps usually use some form of peristaltic pump. Classically,

they use computer-controlled rollers compressing a silicone-rubber tube through

which the medicine flows. Another common form is a set of fingers that press on

the tube in sequence.

Small-volume pumps usually use a computer-controlled motor turning a screw that

pushes the plunger on a syringe.

The classic medical improvisation for an infusion pump is to place a blood

pressure cuff around a bag of fluid. The battlefield equivalent is to place the bag

under the patient. The pressure on the bag sets the infusion pressure. The pressure

can actually be read-out at the cuff's indicator. The problem is that the flow varies

dramatically with the patient's blood pressure (or weight), and the needed pressure

varies with the administration route, potentially causing risk when attempted by an

individual not trained in this method.

Places that must provide the least-expensive care often use pressurized

infusion systems. One common system has a purpose-designed plastic "pressure

bottle" pressurized with a large disposable plastic syringe. A combined

flow restrictor, air filter and drip chamber helps a nurse set the flow. The parts are

reusable, mass-produced sterile plastic, and can be produced by the same machines

that make plastic soft-drink bottles and caps. A pressure bottle, restrictor and

chamber requires more nursing attention than electronically controlled pumps. In

the areas where these are used, nurses are often volunteers, or very inexpensive.

The restrictor and high pressure helps control the flow better than the

improvised schemes because the high pressure through the small restrictor orifice

reduces the variation of flow caused by patients' blood pressures.

An air filter is an essential safety device in a pressure infusor, to keep air out

of the patients' veins: doctors estimate that 0.55 cm³ of air per kilogram of body

weight is enough to kill (200–300 cm³ for adults) by filling the patient's heart.

Small bubbles could cause harm in arteries, but in the veins they pass through the

heart and leave in the patients' lungs. The air filter is just a membrane that passes

gas but not fluid or pathogens. When a large air bubble reaches it, it bleeds off.

Some of the smallest infusion pumps use osmotic power. Basically, a bag of

salt solution absorbs water through a membrane, swelling its volume. The bag

presses medicine out. The rate is precisely controlled by the salt concentrations and

pump volume. Osmotic pumps are usually recharged with a syringe.

Spring-powered clockwork infusion pumps have been developed, and are

sometimes still used in veterinary work and for ambulatory small-volume pumps.

They generally have one spring to power the infusion, and another for the alarm

bell when the infusion completes.

Battlefields often have a need to perfuse large amounts of fluid quickly, with

dramatically changing blood pressures and patient condition. Specialized infusion

pumps have been designed for this purpose, although they have not been deployed.

Many infusion pumps are controlled by a small embedded system. They are

carefully designed so that no single cause of failure can harm the patient. For

example, most have batteries in case the wall-socket power fails. Additional

hazards are uncontrolled flow causing an overdose, uncontrolled lack of flow,

causing an underdose, reverse flow, which can siphon blood from a patient, and air

in the line, which can cause an air embolism.

Safety features available on some pumps

The range of safety features varies widely with the age and make of the pump.

A state of the art pump in 2003 may have the following safety features:

Certified to have no single point of failure. That is, no single cause of failure

should cause the pump to silently fail to operate correctly. It should at least

stop pumping and make at least an audible error indication. This is a minimum

requirement on all human-rated infusion pumps of whatever age. It is not

required for veterinary infusion pumps.

Batteries, so the pump can operate if the power fails or is unplugged.

Anti-free-flow devices prevent blood from draining from the patient, or

infusate from freely entering the patient, when the infusion pump is being set

up.

A "down pressure" sensor will detect when the patient's vein is blocked, or the

line to the patient is kinked. This may be configurable for high (subcutaneous

and epidural) or low (venous) applications.

An "air-in-line" detector. A typical detector will use an ultrasonic transmitter

and receiver to detect when air is being pumped. Some pumps actually

measure the volume, and may even have configurable volumes, from 0.1 to 2

ml of air. None of these amounts can cause harm, but sometimes the air can

interfere with the infusion of a low-dose medicine.

An "up pressure" sensor can detect when the bag or syringe is empty, or even if

the bag or syringe is being squeezed.

A drug library with customizable programmable limits for individual drugs

that helps to avoid medication errors.

Mechanisms to avoid uncontrolled flow of drugs in large volume pumps (often

in combination with a giving st based free flow clamp) and increasingly also in

syringe pumps (piston-brake)

Many pumps include an internal electronic log of the last several thousand

therapy events. These are usually tagged with the time and date from the

pump's clock.

Usually, erasing the log is a feature protected by a security code, specifically to

detect staff abuse of the pump or patient.

Many makes of infusion pump can be configured to display only a small subset

of features while they are operating, in order to prevent tampering by patients,

untrained staff and visitors.

Safety issues

Infusion pumps have been a source of multiple patient safety concerns, and

problems with such pumps have been linked to more than 56,000 adverse event

reports from 2005 to 2009, including at least 500 deaths. [1] As a result, the

U.S. Food and Drug Administration (FDA) has launched a comprehensive

initiative to improve their safety, called the Infusion Pump Improvement

Initiative. [2] The initiative proposed stricter regulation of infusion pumps. It cited

software defects, user interface issues, and mechanical or electrical failures as the

main causes of adverse events.