Recently, the preferred method of expediting the delivery of infants who
experience difficulties in labor or at birth has changed. In the past,
doctors would sometimes apply
medical forceps to assist in "guiding" an infant through a difficult or prolonged
labor and birth. However, while the overall rate of operative-assisted
vaginal delivery has remained stable over the last ten years, doctors
are now choosing to use vacuums rather than forceps, and the rate of vacuum
use has increased relative to forceps application.
These methods of assisting in labor and delivery can be very dangerous,
especially because they do not always work: The percentage of failure
to further descend an infant after forceps application has been reported
as approximately 7%, while it is almost double at 12% after vacuum-assisted
The rates of
injury to infants at birth also goes up tremendously when forceps or vacuum are involved, especially
when both instruments are used, or there is a prolonged use of either
vacuum or forceps. Furthermore, the vacuum pulls on an infant's head
can cause trauma, including subgaleal hematoma, or a pooling of blood
and edema between the skull and skin of a newborn's head. There is
a large increase in risk for this injury when there is a "pop-off"
or "fall-off" of the vacuum.
But what are these instruments? What do they look like, and how are they
used? We would like to provide a basic overview of vacuum and forceps
and how they are used to deliver a baby.
1. What is a vacuum extractor?
vacuum extractor is a machine with a small rubber or soft-polymer cup attached to a vacuum
engine. The soft cup is attached to a baby's skull, and suction ("traction")
is applied to help assist in pulling the baby out, with maternal efforts
being applied throughout. The original vacuum devices had a hard cup,
the most famous of which was called the "Maelstrom".
2. What are forceps?
Forceps are exactly what they sound like: a scissor-like metal apparatus
used for grasping. Different designs allow the forceps to curve to the
shape of a baby's skull when in the normal birth position, facing
down, head first (occiput-anterior) and to assist in guiding a baby during
birth. Some forceps are curved, while others are straighter. Some allow
obstetricians to lock the forceps during contractions, and unlock them
3. When does a doctor decide to use a vacuum extractor or forceps?
The use of a vacuum extractor or forceps usually occurs when a labor is
prolonged, difficult on the mother or baby, when the baby begins to show signs of
hypoxia (hypoxic-ischemic injury, HIE, metabolic acidosis), or when maternal pushing
efforts fail to deliver a baby.
4. What type of birth injuries are common when a vacuum extractor or forceps are used?
- Shoulder dystocia/brachial plexus injuries
- Retinal or total eye hemorrhages
- Bruising, edema, molding, and caput on the baby's scalp or skull
- Skull fractures
- Diastases of the sutures of the skull
- Metabolic acidosis
- Brain injuries
5. What is a brachial plexus injury?
While many of the above injuries are explained elsewhere on our site, we
wanted to define brachial plexus injury. The brachial plexus is a nerve
cluster that is connected to and transmits signals to the spine regarding
movement of the hand, arm, and shoulder. When the nerves in this area
are impacted during birth, movement of these areas of the body can become
partially or totally impaired. When instruments are used, there is an
even greater risk of injury to the brachial plexus, since pulling on a
baby who is stuck in the birth canal with a vacuum or forceps is an extremely
dangerous and risky procedure.
Some of the symptoms of a brachial plexus injury include poor sensation
in the hand, shoulder, or arm, absence of muscle control in the hand,
shoulder, or arm, partial or total paralysis, and poor muscle tone. A
baby might show symptoms of this injury by favoring one arm over the other,
or by exhibiting "dead-arm," where the baby does not support
the injured limb and it remains limp.
Brachial plexus injury can cause Erb's Palsy, a condition that results
from partial or total paralysis of the upper brachial plexus. Klumpe's
Palsy is the corresponding injury that occurs on the lower brachial plexus.
Both are caused when an infant's shoulder becomes impacted on the
mother's pelvis during delivery. This is common in large or malpositioned
babies. This can cause the nerves of this cluster to stretch, causing
short-term or permanent injury, or even tear, causing permanent, total
injury to the arm, shoulder, and hand. There are surgeries and
physical therapies that can assist with these injuries, but the prognosis is typically better
for stretches rather than tears.