ROCKY MOUNTAIN PERINATAL INSTITUTE
Perineal Trauma Reduction VIDEOS FOR PROVIDERS:
ASSISTED DELIVERY USING FORCEPS
Assisted Delivery Using Forceps
Forceps Delivery Overview
DR. MILLER Hello, I’m Dr. Miller. Today we’re going to discuss forceps delivery. As you probably know, forceps deliveries have become less common over the past decade. Reasons for this include: Improvement in the design of vacuum delivery devices The general trend to perform a cesarean delivery for any labor and delivery difficulty Time constraints Medico-legal concerns (and) A desire to minimize perineal trauma As the frequency of forceps deliveries has decreased, the number of skilled obstetricians available and willing to perform and teach the procedure has also diminished. In some areas of the country and in some institutions, the procedure is no longer performed at all. For many decades, forceps operations were a defining procedure of clinical obstetrics. Today, many obstetric residents graduate having never performed the procedure let alone learned how to skillfully conduct a forceps operation. Despite the overall decline in the use of forceps, there are individual providers, institutions, and systems that remain skilled proponents of the procedure. As cesarean delivery rates have risen, seemingly in concert with maternal mortality rates, attention is returning to methods to reduce the incidences. The careful selection of candidates for the procedure and skilled application of delivery forceps can contribute to reducing the frequency, and consequently the morbidity and mortality, associated with cesarean delivery. Poor patient selection and poor performance of the procedure can result in severe maternal or neonatal injury. It’s also true that despite appropriate patient selection and optimal performance of the procedure, forceps operations sometimes fail or can result in maternal genital trauma or neonatal injury. Nonetheless, when considering the risks and benefits of the operation, there remains a place in modern obstetrics for this once revered procedure. In skilled hands, forceps deliveries are associated with a low likelihood of maternal or fetal morbidity. The most frequent, significant complication of forceps operations is maternal perineal trauma. With careful application of the SAFE PASSAGES principles, obstetricians can maintain third- and fourth-degree laceration rates under three to four percent. One large review of perineal trauma in obstetric providers who use exclusively vacuum, or who use vacuum and forceps, or who use forceps exclusively showed the lowest rate of third- and fourth-degree lacerations by the providers who exclusively used forceps. So, skill in the procedure is paramount to determining the outcome.
DR. MILLER Our goal in discussing forceps delivery is to minimize the risk of maternal and fetal trauma. This is part of an overall initiative to reduce perineal trauma. To that end, in 2012, Dr. Bardett Fausett, the Air Force Surgeon General’s Consultant for Obstetrics and Maternal Fetal Medicine, and his colleagues created the acronym SAFE PASSAGES. The acronym is designed to encourage understanding and application of a series of interventions that reduce the incidence, severity, and long-term consequences of perineal trauma. SAFE PASSAGES includes: Start perineal massage at 36 weeks Alleviate maternal fears Facilitate anterior presentations; rotate the baby if necessary Eliminate midline episiotomy Place a warm compress Adduct the thighs at delivery to an angle of 90 degrees or less Straighten the legs at delivery to an angle of 90 degrees or less Support the perineum, keeping your hands and eyes on the baby and perineum at delivery Aim laterally when an episiotomy is needed Go slowly, controlling the head; deliver after a contraction Excel at operative delivery (and) Superbly repair the vagina, vestibule, muscles, and perineum when lacerations do occur While most of these interventions individually reduce the risk of perineal trauma by 50% or more, the individual interventions do not apply to all patients. For these reasons, care providers should consider all of these interventions and apply them appropriately to the women under their care.
Indications for Forceps Delivery
DR. MILLER Let’s begin with limitations and indications for forceps delivery. The procedure can be performed if the leading point of the baby’s skull is at least +2 station and the cervix is fully dilated. If a forceps procedure is considered at +1 station, the procedure should be performed by an obstetrician with advanced forceps skills. Appropriate circumstances for forceps operations include: A prolonged second stage Maternal exhaustion A contra-indication to pushing (or) Current or impending fetal compromise Forceps may also be used to correct malpresentations, deliver the after-coming fetal head at the time of a breech delivery, or to facilitate delivery of the fetal head during a cesarean. After determining that an indication for an operative vaginal delivery is present, the provider must assess the maternal pelvis, adequacy of analgesia, and the fetal head position. The provider then must determine what type of instrument will be the most likely to produce the desired result with the least amount of trauma to the mother and baby.
Risks of Using Forceps
DR. MILLER With forceps deliveries, minor bruising of the baby’s head is not uncommon. In most cases, when forceps are required, considerable fetal head molding has occurred prior to placement of the forceps. It may be useful to inform the family so that they understand that the baby’s cone-shaped head is due to the birthing process and not due to the use of forceps. Other risks and findings not always caused by, but often associated with, forceps deliveries include: Severe tears to the vagina, perineum, or anus Urinary or stool retention after delivery Bumps, bruises, or marks on the baby’s head or face Swollen or misshapen neonatal head Injury to the baby’s facial nerves due to pressure from the forceps, resulting in drooping facial muscles and difficulty closing the eye on the affected side Maternal hemorrhage (or) Neonatal skull fractures or intracranial bleeding While the severity of these injuries varies from one delivery to the next, and all can occur with spontaneous and cesarean deliveries, many of them are not serious. Small bruises quickly resolve, and when the baby’s head is cone-shaped or the facial nerves are injured, they often return to normal within a day or two. More serious injuries to the baby, such as fractures or intracranial bleeding, are quite rare.
DR. MILLER Before using forceps, assess the shape and capacity of the maternal pelvis to ascertain the possibility of delivering the baby. Carefully make sure the baby’s biparietal diameter has passed through the pelvic inlet and that the leading point of the fetal skull is at least +2 station. Only obstetricians with advanced skills should consider forceps operations when the baby is at +1 station. Clearly identify the fetal sagittal suture and the location of the fetal occiput. When scalp edema and molding make the determination difficult, palpation of the back of the fetal ear or visualization with ultrasound can help confirm your assessment. If the fetal face, brow, or chin is presenting, this is a particularly dangerous situation. In such cases, fetal structural or neuromuscular abnormalities are more common, and operative vaginal delivery can be hazardous. In such circumstances, cesarean delivery is generally recommended. An obstetrician with advanced forceps skills may consider using forceps to assist the delivery of a fetus with a face presentation when the chin is directed anteriorly. One of the most important skills of the obstetrician who does forceps deliveries is to learn when to avoid the procedure or abandon it when it is not likely to succeed or is not going well. Depending upon the position of the baby, the situation calls for different kinds of forceps. When the baby is in an occiput anterior position, two types of forceps should be considered: those designed for a molded fetal head, as is common with long second stages and nulliparous women, or those designed for an unmolded head, as is more common with short second stages and parous women. It’s important that you only use forceps with which you are intimately familiar. Most forceps operations can be accomplished with just three instruments. Elliot-type forceps fit an unmolded fetal head. When using Elliot-type forceps, be sure to use the handle screw to set the forceps to fit the rounded fetal head and avoid over compression. Simpson forceps are designed for a molded fetal head, as the cephalic curve is flatter than Elliot-type forceps. When using Simpson forceps, use the Luikart modification when available. These are less likely to produce marks on the fetal head but still produce adequate traction. Kielland forceps are used for rotations. Again, use the Luikart modification when available.
Preparing for Forceps Delivery
DR. MILLER Prior to a forceps delivery, the exact fetal head position must be determined. Trace the sagittal suture to both ends identifying the anterior and posterior fontanels. Where there is a lot of caput, palpating the external auditory meatus and the pinna can be helpful. Ultrasound can also be used to help clarify the position. In addition to identifying the orientation of the fetal head, any head tilting or asynclitism should be identified. After identifying the fetal position, attention is directed to assessing the shape and capacity of the maternal pelvis. To facilitate evaluation of the pelvis, the mother is typically placed in a lithotomy position with the legs properly supported. The pelvic shape plays a large role in the fetal head position during delivery, and helps indicate if and how an operative vaginal delivery should be attempted. All obstetric providers should be intimately familiar with the pelvic types characterized by Caldwell and Moloy.
DR. MILLER Your final preparations for forceps delivery should include assuring that: The maternal buttocks are resting at the end of the table The mother’s bladder has been emptied The mother has adequate anesthesia The forceps articulate well (and) You have shadowed the forceps position for delivery To conduct the forceps delivery, follow these steps: Select the posterior branch of the forceps. Gently place the forceps blade flat against the fetal head, clearing all maternal tissues. Suspend the handle in a vertical position using two fingers of one hand. In the case of the left branch, the left fingers hold the handle. Use three fingers to form a tripod to support and guide the blade onto the fetal occiput. The second and third fingers guide the toe of the blade against the fetal head and keep maternal tissue from coming between the fetal head and the blade. The thumb is used to keep the cephalic curve of the heel of the blade flat against the fetal head and guide the placement around the head to the malar eminence. The branch should easily fall into place as the handle traverses a wide arching “C” shape. The blade is not to be fit to the vagina or pelvis, but rather to the fetal head. If any resistance is encountered, gentle elevation of the forceps blade with the index finger, while simultaneously lowering the handle and moving it more lateral to the midline, will usually help relieve the resistance and complete the placement of the branch. If resistance remains, do not force the placement. Reconsider an alternative procedure. When successfully placed, the blade should lie evenly along the side of the fetal face, in the pelvic axis, and reach beyond the malar eminences symmetrically covering the space between the fetal orbits and ears. The same procedure is repeated with the anterior branch. If the branch on the maternal right is placed first, the forceps will need to be uncrossed on the perineum to articulate at the lock. If the handle of one branch protrudes from the vagina significantly more than the other branch, either one of the branches has not been placed over the malar eminence, or there is some degree of asynclitism. If there is asynclitism, move both branches of the forceps laterally across the midline toward the branch that protrudes the least. Typically this allows easy articulation. As the lock is articulated, palpate to evaluate the relationship of the blades to the fetal sutures. Three checks are important. First, make sure the sagittal suture is perpendicular to the plane of the branches throughout the sutures’ length. Next, confirm that the posterior fontanel is one fingerbreadth away from the plane of the upper edge of the blades and equidistant on both sides. This makes the plane of traction lie directly over the flexion or center point of the fetal occiput. Finally, if a fenestrated blade is used, the space between the heel of the fenestration and the fetal occiput should not admit more than a single fingertip. Frequently, the blades do not articulate perfectly or rest equidistant from the fontanel and suture line. In this situation, most commonly the anterior blade has not crossed over the fetal malar eminence. Reposition the blade or blades as necessary prior to full articulation or traction. Sometimes, placing the contralateral index finger under the blade against the head can identify a gap between the head and the blade, either proximally or distally. This can usually be corrected by gently lowering the handle of the branch while simultaneously elevating the blade with the palpating index finger. The placement of the forceps should be a delicate operation requiring minimal force. Once the forceps have been placed appropriately, their position relative to the suture lines should be maintained throughout any rotation or extraction movements. This assures that the fetus will traverse the path of least resistance and that the blades do not slip over the fetal tissue. Slippage suggests obstruction that must immediately be corrected, or the procedure should be abandoned.
Hand Placement for Forceps Delivery
DR. MILLER Proper hand placement is crucial during a forceps delivery. One hand should be placed on the shanks of the forceps so as to allow the second or third finger, during rotations, or the fourth or fifth finger, during extractions, to maintain contact with the fetal sutures. This allows the relationship of the forceps to the fetal head to be continuously verified. Unless contra-indicated, maternal expulsive efforts should be encouraged. During the extraction, the non-dominant hand should be positioned on the shanks of the forceps. This hand performs two functions. First, it provides downward traction to guide the fetal head through the Curve of Carus, or the pelvic curve. Second, it assures continuous assessment of the relationship between the forceps and the fetal head. The dominant hand is used to provide outward traction. To avoid placing too much compression on the fetal skull, the operator’s dominant hand should grip the handles as close to the lock as possible. As the fetus clears the symphysis and can be controlled through the perineum via the modified Ritgen maneuver, the provider should consider removing one or both branches of the forceps. Remove the anterior blade first by gently moving it outward and curving the handle up over the opposite maternal thigh. If the forceps are left in place to complete the delivery, move the dominant hand to protect the perineum and help control descent and fetal head extension. The non-dominant hand also helps control the descent with the forceps and completes the extraction very slowly. Avoid elevating the handles out of plane with the fetal sutures to avoid vaginal sulcus tears or perineal trauma. As delivery approaches, the tension on the perineum can be greatly relieved by adduction and extension of the maternal thighs by assistants. As the fetal head extends at delivery, the handles of the forceps will almost be perpendicular to the floor.