ROCKY MOUNTAIN PERINATAL INSTITUTE
Perineal Trauma Reduction VIDEOS FOR PROVIDERS:
ASSISTED DELIVERY USING VACUUM
Assisted Delivery Using Vacuum
Vacuum Delivery Introduction
DR. FAUSETT Hello, I’m Dr. Bardett Fausett, the Air Force Surgeon General’s Consultant for Obstetrics and Maternal Fetal Medicine. Welcome to this video. Here we will focus on minimizing trauma during vacuum-assisted vaginal deliveries. We will also address some of the related interventions of the SAFE PASSAGES algorithm. Here we will assume some degree of familiarity and experience with the procedures. We will review some of the key concepts briefly, but we’ll focus on pearls specifically aimed at maximizing the effectiveness of the procedures while minimizing the risk of trauma to mother and baby. Vacuum deliveries can appear deceptively simple, particularly when they are compared with forceps. However, many of the same principles that apply to the proper use of forceps apply to vacuum deliveries. When improperly used, vacuum instruments are prone to failure and to increasing the incidence of fetal trauma, including potentially fatal intra- or extra-cranial hemorrhage. Practice and application of the principles covered in this video will maximize safety and efficacy when you choose to perform a vacuum-assisted delivery.
Vacuum Delivery Overview
DR. MILLER Hello, I’m Dr. Miller. Today we’re going to discuss operative vaginal delivery using a vacuum. We’ll focus on methods of performing the procedure while minimizing 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 Vacuum Delivery
DR. MILLER It is important to know when it’s appropriate to use a vacuum, and to understand the associated risks. There are specific prerequisites for cases in which a vacuum delivery is being considered. These include: The cervix must be completely dilated The fetal head engaged in the pelvis (and) The fetal head position known Knowing the fetal head position is critical for vacuum placement in order to guide the smallest diameter of the baby’s head through the maternal pelvis. Indications for vacuum delivery include: A prolonged second stage Maternal exhaustion (and) Fetal heart rate patterns that suggest fetal compromise or impending compromise Contra-indications for vacuum delivery include: Gestational age less than 34 weeks Suspected fetal platelet disorder Severe maternal Idiopathic Thrombocytopenia Purpura, or ITP, or A family history of hemophilia
Risks of Vacuum Delivery
DR. MILLER There are specific risks associated with vacuum delivery. These include: Maternal genital trauma, particularly injury to the vaginal canal from entrapment of maternal tissue inside of the suction cup Bleeding under the baby’s scalp, or cephalohematoma Bleeding underneath the baby’s periosteum, or subgalial hematoma, and Bleeding inside the baby’s skull, or intracranial hemorrhage In addition, compared to forceps deliveries, vacuum deliveries are more likely to: Fail to complete the delivery vaginally (and) Result in a shoulder dystocia Following the practices outlined in the SAFE PASSAGES acronym minimizes the risk of perineal trauma during vacuum delivery. For example, consider preparing the perineum with a warm compress if time allows.
DR. MILLER After carefully identifying the fetal head position and station, it’s critical to place the suction cup symmetrically astride the sagittal suture at the median flexion point, also known as the pivot point. While avoiding maternal vaginal tissue, create the vacuum pressure according to the manufacturer’s specifications. When well applied, this will pull part of the scalp into the cup and create an artificial caput, or chignon. Once the cup is applied, sweep the circumference of the cup to ensure that no vaginal or cervical tissues have been inadvertently trapped. At this point, apply sustained downward traction along the pelvic curve using two hands. Use your dominant hand to exert traction and your non-dominant hand to monitor the progress of descent and prevent cup detachment by applying counter pressure directly to the vacuum cup. The traction should be applied in concert with uterine contractions and the mother’s pushing. Discontinue traction when the contraction ends and the mother stops pushing. As it flexes and descends, the fetal head may rotate, resulting in passive rotation of the cup. Although this is to be expected, do not attempt to manually rotate the fetal head with the vacuum. Descent of the vertex should occur with each application of traction. Once the fetal head begins to crown, consider releasing the suction, removing the cup, and continuing with normal delivery. Alternatively, you can leave the cup on the baby’s head, but be sure to provide some counter traction on the cup against the fetal head to avoid breaking the suction and getting a pop–off. If you leave the cup on, you’ll need a skilled assistant to help protect and support the perineum as the baby delivers since both of your hands will be occupied. Whether you take the vacuum off to complete the delivery or get the help of an assistant and leave the vacuum on, two large European studies have demonstrated that specific hand position and coaching at the time of delivery can reduce the risk and severity of maternal genital trauma. These studies recommend the following method: The delivery assistant presses the fetal head with their left hand to control the speed of crowning through the vaginal introitus The right hand supports the perineum and tries to grip the baby’s chin through the perineum When a good grip has been achieved, the mother is asked to stop pushing and breathe rapidly while the provider slowly helps the fetal head through the introitus When most of the head is out, the perineal ring is pushed under the baby’s chin
Preparing for Vacuum Delivery
DR. MILLER Before using a vacuum extractor, make sure the baby’s position is clearly identified. In order for the molded fetal head to traverse the maternal pelvis with the least degree of resistance, the vacuum cup must be placed over the center of the fetal flexion point. Several elements of the SAFE PASSAGES acronym are particularly important when performing a vacuum delivery. These include facilitating anterior presentations, adducting the thighs, straightening the legs, and supporting the perineum at delivery. Remember to aim laterally when an episiotomy is needed. When the baby is crowning, go slowly while controlling the head and delivering after a contraction. Some vacuum instruments are designed to facilitate spontaneous auto-rotation of the fetal head to an occiput anterior position. It is wise to develop skill with such instruments as the risk of third- and fourth-degree lacerations is cut in half when babies auto-rotate to an occiput anterior position.
Vacuum Delivery Conclusion
DR. MILLER In keeping with SAFE PASSAGES, don’t forget that communication and encouragement are important to reduce maternal fear and anxiety. This will help her cooperate with you and help relax the pelvic floor muscles facilitating the delivery. The adrenergic hormones, secreted under conditions of anxiety and stress, tighten the lower uterine segment and pelvic floor and make contractions less effective. Remember to reduce the resistance and tension on the maternal perineum by delivering the baby when the maternal thighs are not flexed more than 90 degrees and the thighs are less than 90 degrees apart. While such a position is easily obtained in side-lying and hands and knees deliveries, this position can also be achieved with the mother on her back as long as the legs are positioned as recommended in SAFE PASSAGES. On the other hand, when the maternal thighs are flexed and abducted, as is common in a squatting or flexed lithotomy position, the perineum is stretched taut and more likely to tear with delivery. SAFE PASSAGES positioning does not increase the risk of shoulder dystocia. The literature is very clear that midline episiotomy should be avoided during vacuum deliveries. On the other hand, there is some literature that supports performing mediolateral episiotomies for all operative deliveries. Many practicing obstetricians do not subscribe to this practice for all operative deliveries, but when the baby is particularly large or the perineum unusually short, it’s important to consider a mediolateral episiotomy. Ultimately, this is a matter of experience and judgment. If you are facile with the other interventions of the SAFE PASSAGES acronym, you will minimize the risk of severe perineal lacerations without routinely cutting mediolateral episiotomies, even with operative deliveries.