What is drug delivery?
Drug delivery is the way in which medications are given
to ICU patients. Due to the advances in medicine, drugs
may be delivered in many different ways using many
different delivery systems including: by mouth (pills or
suspensions), through the vein (intravenously), through
the artery (arterially), topically through the skin (transdermally),
through the rectum (suppository), through the eye
(ocular), through the lungs (inhaled), by injection into
the skin (subcutaneously), by injection into the muscle
(intramuscularly), and under the tongue (sublingually).
Pills or Suspensions
It is common to give ICU patients medications by
mouth. Many patients will be able to take pills in the
usual fashion. Patients who have feeding tubes in place
are usually given their medications through these tubes.
Medications may have to be crushed or dissolved in water
to be given through these tubes. Some of the medications
come in a suspension or liquid from and can be directly
given through the tubes or be taken by mouth.
Occasionally the patient's stomach or intestines may not
work properly and another way to give medications must
be found.
Intravenously
Many of the medications that ICU patients receive
must be given intravenously. Medications may be given by
"IV push" where the nurse injects the medication
directly into the IV line while other medications need
to be given more slowly. Medications needing more time
to be given may be slowly infused into the patient
through a small IV bag (called an IV piggy-back)
attached to the main IV line. Some medications and IV
fluids need to be given through an IV pump system. The
IV pump gives the fluid or medication at a very specific
rate and over a very specific time. This prevents the
medication or fluid to be given to slowly or to quickly.
The IV pumps vary in size and shape. IV pumps have
alarms that you may hear.
Arterially
Very few medications are given through the artery in
ICU patients. The most commonly used agent given through
the artery is called contrast material. This is truly
not a medication but rather an agent that is given to
outline the artery if damage or blockage of the artery
is suspected. This agent is usually given to the patient
in the radiology department so that special x-rays of
the artery can be taken at the same time.
Transdermally
Several medications are absorbed through the skin.
The medication may be in the form of a cream or a patch.
These medications may need to be placed on the skin
several times a day or only replaced after several days.
Nitrogylcerin (used for chest pain), clonidine (used for
high blood pressure) and fentanyl (used for pain) are a
few examples. Some patients develop skin irritation from
this form of drug delivery.
Rectal
Many medications may be absorbed through the mucosa
(moist skin) of the rectum. The medications are usually
prepared in a wax suppository that melts when given to
the patient to allow for slow absorption. The amount of
medication that is absorbed is not always predictable.
Tylenol is one example of this from of medication.
Ocular
Medications may be delivered directly to the moist
covering (conjuctiva) over the eye. These medications
are given for eye problems only. Examples include
glaucoma and antibiotic eye drops.
Inhaled
Many medications are given directly into the lungs by
the inhaled route. These medications frequently act to
treat conditions of the lungs. The medications may be
given through a hand held inhaler or nebulizer (small
machine that produces a mist that includes the
medication). These medications are usually used to treat
asthma, emphysema, and rarely infections. In an
emergency situation, several life saving medications can
be given directly into the lungs through a breathing
tube.
Subcutaneously
Medications may be given as an injection directly
underneath the skin. The medication is slowly absorbed
into the body from the tissue just beneath the skin. Two
of the most common medications given in this way are
insulin (used to treat diabetes) and heparin (used to
thin the blood). The absorption of medications through
the subcutaneous tissue can occasionally be
unpredictable in ICU patients.
Intramuscularly
Medications may be given as an injection directly
into the muscle. The medication is slowly absorbed into
the body from the muscle. Two of the most common
medications given this way to ICU patients are
medications to treat pain and nausea (sick to the
stomach). Medications given into the muscle are usually
associated with pain when injected.
Sublingually
Medications may be given under the tongue and get
into the body through the mucosa (moist skin). Because
the tongue has a rich blood vessel supply some
medications are very well absorbed given this way. The
best example is nitroglycerin. This medication is very
effective when given sublingually.
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