Drugs for Pain Relief
Various types of medication are available for pain relief during labor; many can be used alongside natural forms of pain relief.
For some, natural pain
relief may not be sufficient to enable them to deal with the increasing
intensity of contractions, and they may choose to use medication in
combination with natural techniques. In some situations, for example if
labor is induced or augmented , contractions may start strongly rather than build up gradually and a stronger type of pain relief may be needed.
There are several types
of medical pain relief available, which fall into two groups. Analgesic
drugs dull the perception of pain, while anesthesia, which may be
regional or general, numbs pain totally. In regional anesthesia, also
known as a nerve block, local anesthetic drugs are injected around
nerves that supply a particular area. There are several types of
regional nerve block: epidurals and spinal blocks numb sensation in the
abdomen and are used to reduce the pain of contractions; a pudendal
block numbs sensation in the vagina and perineum and may be used in a
forceps delivery. Occasionally, a general anesthetic is given during a
cesarean.
Since all labors are
different, it’s not possible to have a “one size fits all” approach to
pain relief. Being flexible and informed will help you feel in control.
Read any literature from your doctor, go to prenatal classes, and ask
questions. Try to eliminate any worries by increasing your knowledge,
for example by asking if it’s possible to attend a childbirth education
class at the hospital that discusses the pros and cons of each type of
pain relief. Keep in mind that some childbirth classes, like Lamaze and
the Bradley method, can teach you breathing and relaxation techniques
that may help reduce your need for pain medication during labor.
Pain relief plan
Having a birth plan
ahead of time that outlines the circumstances during which you would
resort to using medication for pain relief may be helpful for some
women. For example, you may want to try to remain medication-free unless
the pain is so intense, it interferes with your ability to hold a
normal conversation, or it doubles you over in pain. Perhaps you’ll seek
relief if your labor drags on hours longer than you expected and you
need some respite to sleep for a while to regain your strength for the
upcoming pushing that you’ll be doing. Whatever the case, you may feel
more in control if you know ahead of time what your limits are and when
you want to say yes to pain medication, rather than being overwhelmed by
the situation, if you don’t give it much thought beforehand.
Opioids
These belong to a group
of drugs called narcotics (which literally means sleep-inducing), which
includes morphine. They attach themselves to receptors in the brain or
nerves and block the transmission of pain.
Tranquilizers
These drugs don’t
relieve pain, but they can help to relieve anxiety and help a women
relax for several hours during early labor. Some women who are very
anxious about the impending pain or of labor and childbirth may seek
this sort of medication. Tranquilizers may be given orally,
intravenously, or injected into a large muscle. Oral dosage takes the
longest to take effect. Some women dislike what tranquilizers do to
them, since they may feel drowsy and out of control. If the dose is very
high, women may nod off between contractions. It may be hard for a
woman to fully remember her labor experience if she’s taken
tranquilizers. The drugs also effect the baby, decreasing his activity
and muscle tone during and after birth. For these reasons, tranquilizers
are not for everyone, but in certain circumstances, they can help a
woman feel less anxious about labor.
Epidurals
An epidural is a
regional anesthetic that can be given at any stage of labor to numb the
abdomen and therefore block the pain of contractions, but it’s typically
given when the woman is at least 4 cm dilated. In some cases, if a
woman’s labor progresses very quickly and she doesn’t request one right
away, she may not be able to get one before delivery. Epidurals are the
most popular form of pain relief during labor in the US, with more than
half of pregnant women delivering in hospitals choosing this treatment.
How epidurals work
A hollow needle is
inserted between two vertebrae in the lower back. A tiny plastic tube is
then passed through the needle and into the epidural space surrounding
the spinal cord. A local anesthetic is injected into the needle and
flows through the tube into the epidural space so that the nerve roots
carrying the pain stimulus to the brain are coated with anesthetic and
pain is reduced or completely blocked. This will affect sensation in
your legs so that you need to remain in bed and your baby will be
closely monitored. A stronger epidural also affects sensation in your
bladder, so you will need to have a catheter. Used late in labor, a
stronger epidural may mean that you need help to push the baby out,
since the pelvic floor muscles will be heavy and ineffective. In this
case, your doctor will put a hand on your abdomen to feel when a
contraction starts and will tell you when to push. In some cases, an
assisted delivery becomes necessary.
When are epidurals used?
Epidurals can be
used throughout labor, but they’re typically given during active labor
when a woman is 4–5 cm dilated. Since everyone has varying pain
thresholds, the time when one is requested varies. There are factors to
bear in mind should you opt for an epidural late in labor. To minimize
the risks, you must remain completely still during the placement of the
epidural tube. If your labor has progressed too far to enable you to do
this, the anesthesiologist may refuse to proceed with an epidural for
your own interest. Also, if you choose to have an epidural late in
labor, it may be necessary to give a high dose so that it takes effect
in time, which has disadvantages (see Considering an epidural).
If you’re considering
using an epidural, inform your doctor early in labor so that she can
consult the anesthesiologist. The anesthesiologist may then discuss this
with you and take a brief medical history to ensure that it’s safe for
you to have an epidural. She will discuss any risks, and answer any
questions that you or your partner has, all of which can save time later
on if you decide to go ahead.
There are occasions
when an epidural is not advised. These include cases where a woman has
had spinal surgery or is taking blood-thinning medication. Rarely, a
woman may have an infection that could be exacerbated by an epidural.
Side effects
There are a number of minor side effects. The medication can cause blood pressure to fall, so this will be monitored (see How an epidural is done). If it does fall, you’ll be given fluids and medication, and subsequent doses may be reduced.
It’s common to
experience itching with epidurals, caused by the release of histamine
from the opioid component of a mobile epidural. Histamine is a substance
released by the body during an allergic reaction that can cause
itching. The itch can be treated, but in most cases it gets better on
its own. If you develop an itch, a greater concentration of local
anesthetic alone will be used.
It’s not unusual to
shiver with an epidural, although this is a more common side effect if a
concentrated local anesthetic is used, as is the case for a cesarean
delivery.
Epidural pain
relief can cause a rise in temperature. If this occurs, you’ll have a
blood test to eliminate an infection since this can also cause your
temperature to rise. You will be given preventative antibiotics while
waiting for the blood test results, and acetaminophen to bring your
temperature back to normal.
Problems with epidurals
In addition to side
effects, there can occasionally be problems with the effectiveness of an
epidural. The anesthetic may not spread evenly in the epidural space,
which may be caused by the epidural tube sitting on one side of the
epidural space. This can mean that pain relief only occurs on one side
of the body. If this occurs, the anesthesiologist will try to reposition
the tube and give another dose of anesthetic. If this doesn’t work, the
only other solution is to redo the entire epidural.
Sometimes, one
spot can remain painful, usually in the groin area or low down in the
front of the abdomen, which is referred to as a “missed segment.” This
results from a single nerve root not being coated with the local
anesthetic. Again, the anesthesiologist may reposition the tube.
Sometimes, a stronger local anesthetic or an opioid is used to numb the
area. If a persistent missed segment is too uncomfortable, the
anesthesiologist may do a combined spinal epidural block, known as a CSE.
It’s thought that
epidural pain relief may prolong the second stage of labor. It also
increases your chances of having an assisted delivery, especially if a
high dose of anesthetic is given toward the end of labor, which affects
your ability to push. However, an epidural doesn’t increase the chance
of a cesarean and doesn’t, despite common misconceptions, cause
long-term backache after the birth.
Spinal block
This is similar to an
epidural in that a needle is put in your back and pain relief is
achieved by blocking nerve fibers that supply the pelvic organs.
However, in a spinal block, the needle is passed through the epidural
space to pierce the membrane covering the spinal cord (the dura) so that
anesthetic can be injected into the fluid around the spinal cord; no
tubes are left in place. The needle used for a spinal block is smaller
than that used for an epidural, which means it’s less painful to insert.
There is still a risk of a headache as with an epidural (see An Epidural “headache”) and the side effects should be treated the same way.
A smaller dose of
anesthetic is needed and it works very quickly: pain relief is almost
immediate, whereas an epidural takes 10–20 minutes. However, the use of a
spinal block is limited because only a single dose of medication can be
administered. As a result, spinal blocks are usually reserved for use
during a cesarean, or for an assisted delivery when an epidural isn’t in
place.
Combined spinal epidural (CSE) or “walking epidural”
This involves both a
spinal injection and putting an epidural in place. It’s sometimes done
when problems are encountered with an epidural (see Epidurals)
and is also used for a cesarean. A CSE gives pain relief throughout
labor. However, it’s a specialized technique and isn’t offered in all
units.
Pudendal blocks
This type of
regional anesthesia involves injecting a local anesthetic into the
vagina where the pudendal nerves are located to reduce pain in the
vagina and perineum. The pudendal needle is quite long and thick, so
before the injection is given, a cold anesthetic spray is applied to the
area. The anesthetic has no effect on the baby and can be used with
other medications. It takes effect very quickly and is sometimes used
just before birth to aid an assisted forceps delivery.
General anesthesia
Most cesareans are
conducted using regional anesthesia. However, in some cases general
anesthesia, where the mother is put to sleep, is necessary. This may be
because of a failure of regional anesthesia, blood-clotting problems in
the mother, an infection in the mother’s bloodstream, or persistent
fetal distress.
The procedure
Precautions are
taken to minimize the risks to you and your baby. You’ll be given an
antacid to reduce stomach acid. Often a catheter is inserted into the
bladder and antiseptic is applied to the abdomen before you’re put to
sleep to minimize the baby’s exposure to the anesthetic.
As the mother is put to
sleep, a face mask is held tightly over her nose and mouth. Because a
major risk during general anesthesia is undigested food or liquids in
the stomach re-entering the mouth and going into the lungs (which can
cause damage) you’ll likely be told not to eat or drink anything once
labor begins (because labor usually slows digestion), in case you need
general anesthesia. You may be able to have ice chips, though. Once
asleep, an anesthesiologist inserts a tube through your mouth and down
your throat so that oxygen can easily reach your lungs. You may
therefore have a sore throat when you wake up.
During the
surgery the anesthesiologist cares for the mother, giving painkillers
and anti-nausea medicine when needed. The baby is cared for by the
doctor. Depending on hospital procedure, your partner may or may not be
present for the birth. However, no hospitals allow the partner to be
present while the mother is being put to sleep.
After the surgery
The procedure takes about
an hour. The mother is woken 5–10 minutes after the surgery. The baby
is kept with the mother at all times unless he needs extra care.
Since general
anesthesia doesn’t give localized pain relief, it’s normal to need pain
relief afterward. Oral medicine will be given regularly and
morphine-based medication may be given for a day or two.
Up until 150 years ago, there were few options for pain relief during childbirth.
The history of modern
obstetric pain relief began in the mid-19th century with the discovery
of chloroform. Nitrous oxide and opioids followed and at the start of
the 20th century, enthusiasm for pain-relieving drugs was so great that
they were overused, with women in labor in a state of
near-unconsciousness. The natural childbirth movement in the 1960s and
1970s was a reaction to such overuse of drugs. In the 1970s another
revolution was at hand as epidurals became available.
