The ability to obtain intravenous (IV) access is an
essential skill in medicine and is performed in a variety of settings
by paramedics, nurses and physicians. Although the procedure can
appear deceptively simple when performed by an expert, it is in
fact a difficult skill which requires considerable practice to perfect.
The rate of fluid flow is proportional to radius to
the power of four, and inversely proportional to length; therefore
fluids run fastest through a shorter and larger diameter tube. Also
note that the smaller the gauge of a needle, the larger its diameter
i.e. a 14 gauge needle has larger diameter than a 21 gauge needle.
By starting a peripheral IV, you gain access to the
peripheral circulation of a patient, which will enable you to sample
blood as well as infuse fluids and IV medications. IV access is
essential to manage problems in all critically ill patients. High
volume fluid resuscitation may be required for the trauma patient,
in which case at least two large bore (14-16 G) IV catheters are
usually inserted. All critically ill patients require IV access
in anticipation of future potential problems, when fluid and/or
medication resuscitation may be necessary.
Some patients have anatomy that poses a risk for fluid
extravasation or inadequate flow and peripheral IVs should be avoided
in these situations. Examples include extremities that have massive
edema, burns or injury; in these cases other IV sites need to be
accessed. For the patient with severe abdominal trauma, it is preferable
to start the IV in an upper extremity because of the potential for
injury to vessels between the lower extremities and the heart. For
the patient with cellulitis of an extremity, the area of infection
should be avoided when starting an IV because of the risk of inoculating
the circulation with bacteria. As well, an extremity with an indwelling
fistula or on the same side of a mastectomy (occasionally a problem)
should be avoided because of concerns about adequate vascular flow.
The main complications of an IV catheter are infection
at the site and development of superficial thrombophlebitis in the
vein that is catheterized. It is also common for the IV sites to
The potential for contact with a patient's blood while
starting an IV is high and increases with the inexperience of the
operator. Gloves must be worn while starting an IV and if the risk
of blood splatter is high, such as an agitated patient, the operator
should consider face and eye protection as well as a gown. Trauma
protocol calls for all team members to wear gloves, face and eye
protection and gowns. As well, once removed from the protective
sheath, IV catheters should either go into the patient or into an
appropriate sharps container.
Important: Recapping needles, putting catheters back into their
sheath or dropping sharps to the floor (an unfortunately common
practice in trauma) should be strictly avoided. Recapping of
needles is one of the commonest causes of preventable needle stick
injuries in health care workers.
Peripheral IV sites
Generally IV's are started at the most peripheral
site that is available and appropriate for the situation. This allows
cannulation of a more proximal site if your initial attempt fails.
If you puncture a proximal vein first, and then try to start an
IV distal to that site, the fluid may leak from the injured proximal
vessel. The preferred site in the emergency department is the veins
of the forearm, followed by the median cubital vein that crosses
the antecubital fossa. In trauma patients, it is common to go directly
to the median cubital vein as the first choice because it will accommodate
a large bore IV and it is generally easy to catheterize. In circumstances
where the veins of the upper extremities are inaccessible, the veins
of the dorsum of the foot or the saphenous vein of the lower leg
can be used. In circumstances in which no peripheral IV access is
possible a central IV can be started.
All necessary equipment should be prepared, assembled
and available at the bedside prior to starting the IV. Basic equipment
- gloves and protective equipment
- appropirate size catheter 14-25 G IV catheter
- non-latex tourniquet
- alcohol swab/other cleaning instrument
- non-sterile 2x2 gauze
- sterile 2x2 gauze (this is not practiced in nursing)
- 6x7cm Tegaderm™ Transparent Dressing
- 3 pieces of 2.5 cm tape approximately 10 cm in length
- IV bag with solution set (tubing) (flushed and ready) or
- sharps container
To prepare the IV line, protective caps are removed
from the fluid bag and the spiked end of the IV tubing. The regulating
clamp for the IV line should be closed. The spiked end of the IV
tubing is inserted into the receptacle on the IV bag while holding
the IV bag inverted. The bag is then held upright with the IV line
hanging from the bottom. The drip chamber should be filled half-way
by pinching it and releasing. Following this the bag should be hung
for the IV pole, at a point above the patient, and the regulating
clamp should be opened to "flush" the line of air bubbles
prior to connection to the patient.
Establishing a peripheral intravenous line
- Assemble your equipment.
- Don a pair of appropriately sized non-latex examination gloves.
- Apply tourniquet to the IV arm above the site.
- Visualize and palpate the vein.
- Cleanse the site with a chlorhexidine swab using an expanding
- Prepare and inspect the catheter:
Remove the catheter from the package.
Push down on the flashback chamber to ensure it is tight.
Remove the protective cover.
Inspect the catheter and needle for any damage or contaminants.
Spin the hub of the catheter to ensure that it moves freely
on the needle
Do not move the catheter tip over the bevel of the stylet.
- Stabilize the vein and apply countertension to the skin.
- Insert the stylet through the skin and then reduce the angle
as you advance
through the vein.
- Observe for "flash back" as blood slowly fills
the flash back chamber.
- Advance the needle approximately 1 cm further into the vein.
- Holding the end of the catheter with your thumb and index
finger, pull the
needle (only) back 1 cm with your middle finger.
- Slowly advance the catheter into the vein while keeping tension
on the vein and skin.
- Remove the tourniquet.
- Secure the catheter by placing the Tegaderm™ over the
lower half of the catheter hub taking care not to cover the
IV tubing connection
- Occlude the distal end of the catheter with the 3rd, 4th and
5th fingers of your non-dominant hand.
- Secure the catheter hub with your thumb and index finger
and carefully remove the needle.
- Place the needle into the sharps container.
- Remove the cover from the end of the IV tubing and insert
the IV tubing into the hub of the catheter.
- Secure the tubing to the catheter by screwing the Luer Lock
- Open up the IV roller clamp and observe for drips forming
in the drip chamber.
- Check that the IV is infusing into the vein by occluding
the vein distal to the catheter and observing that the drips
stop forming and then restart once the vein is released.
- Adjust the IV drop to keep the vein open rate (TKVO) of approximately
30 - 60 mL/hr (one drop every 5 - 10 seconds for 10 gtts/mL
- Place a piece of tape over the catheter hub.
- Make a small (kink free) loop in the IV tubing and place
a second piece of tape over the first (piece of tape) to secure
- Place a third piece of tape over the IV tubing above the
- Ensure that the IV is properly secured and infusing properly.
- Ensure that all "sharps" are placed in the sharps
To remove the IV
- Shut off the IV by closing the roller camp.
- Remove the tape and Tegaderm™ from the tubing and catheter.
- Place a non-sterile 2x2 gauze over the IV site and remove
the catheter from the arm and secure it in place with a piece