Dennen's Forceps Deliveries.pdf
This volume retains much of the original text from the previous edition, including explanations of forceps devices and techniques. It also provides the latest College guidelines, a chapter on vacuum-assisted deliveries, and information on the current and changing status of forceps deliveries.
Dennen's Forceps Deliveries.pdf
processing.... Drugs & Diseases > Obstetrics & Gynecology Forceps Delivery Treatment & Management Updated: Jun 15, 2020 Author: Michael G Ross, MD, MPH; Chief Editor: Christine Isaacs, MD more...
Share Email Print Feedback Close Facebook Twitter LinkedIn WhatsApp webmd.ads2.defineAd(id: 'ads-pos-421-sfp',pos: 421); Sections Forceps Delivery Sections Forceps Delivery Overview Practice Essentials
History of the Procedure Epidemiology Presentation Indications Relevant Anatomy Contraindications Show All Workup Treatment Preoperative Details
Intraoperative Details Postoperative Details Follow-up Complications Outcome and Prognosis Future and Controversies Show All Media Gallery References Treatment Preoperative Details Reviewing the indications for operative vaginal delivery and confirming the presence of all the prerequisites for forceps application are crucial steps. In particular, the presentation, position, and station of the presenting part must be reconfirmed just before the procedure.
Maternal verbal consent should be obtained prior to the forceps attempt, although the procedure may need to be performed emergently or after the mother has been medicated. If a planned forceps delivery is to be performed (ie, for maternal medical indications), counseling and consent may be completed prior to the onset of active labor.
The type of forceps to be used depends on the specific indications and conditions. The most commonly used forceps are Simpson forceps, which are used to deliver a molded fetal head, as is commonly seen in nulliparous women. Also commonly used are Tucker-McLane forceps, which have a more rounded cephalic curve, more suitable for the unmolded fetal head commonly seen in multiparous women. Kjelland forceps are made for rotation of the fetal head and lack a pelvic curve. Many instruments are available with the Luikart modification (pseudo-fenestrated).
The decision of what type of anesthesia is used should be made before initiating the delivery. An adequate level of anesthesia should be in effect before forceps application. Although published reports suggest that using only local infiltration anesthesia to the perineal body is enough, the authors believe that this type of anesthesia may be less than adequate. Very few women can tolerate forceps application without, at a minimum, pudendal block anesthesia. Attempts to "force the issue" with inadequate anesthesia may be intolerable to the mother. Pudendal block anesthesia may be augmented with intravenous sedation.
The most crucial point of forceps delivery is knowledge of the presentation position of the fetus. The term pelvic application is used when the left blade is applied on the left side of the pelvis and the right blade is applied on the right side of the pelvis, regardless of the fetal position. Pelvic application is never to be used as a substitute for knowledge of the fetal position; inappropriate pelvic application may cause maternal harm.
Once again, emphasizing that forceps delivery is skill- and training-dependent is important. The operator must have a clear understanding of his or her own capabilities, as well as the safe limits of the procedure, and must not exceed either of these.
After ensuring proper anesthesia and an empty bladder, the fetal position is again checked prior to introducing the instrument. The presence of the sagittal suture in the anteroposterior diameter of the pelvic outlet is confirmed, and the left forceps blade is introduced into the posterior half of the left side of the pelvis and is guided to the appropriate position along the fetal head.
At all times, attention should be given to avoiding the use of excessive force. At the beginning of the application, the blades should be held like a pencil, almost in a vertical position; as the blades are introduced into the vagina, they are brought to a horizontal position. Avoiding levering or forcing the blade with the nonvaginal hand is critical. The fingers in the vagina should only guide the blades and should not apply pressure on or displace the fetal head. The application of the forceps is generally not performed during a uterine contraction; however, properly placed blades may be left in place if a contraction ensues during placement.
In a proper cephalic application, the long axis of the blades corresponds to the occipitomental diameter, with the ends of the blades lying over the posterior cheeks (see image below); the blades should lie symmetrically on both sides of the head. The sagittal suture of the fetal head will be in the middle, and the blades will be equidistant from the sagittal and occipital sutures. At no time should any part of the forceps cover any midline structure. The forceps should lock easily with minimal force and stand parallel to the plane of the floor. The appropriateness of application should be confirmed before applying traction.
During an indicated forceps delivery, traction is applied during contractions. The instrument may be used to maintain the station of the fetal head between contractions. In an emergency, applying continuous traction may be necessary until the fetal head delivers.
After confirming proper forceps application, traction starts parallel to the plane of horizon and is then elevated to an almost vertical position as the fetal head extends, and the forceps are removed as the fetal head delivers through the perineum.
With forceps delivery, less opportunity exists for the maternal tissues to stretch, and episiotomy may be performed to allow a more rapid delivery. The utility of episiotomy in preventing short- and long-term maternal injury is controversial. [8]
After a forceps delivery, thorough examination of both the mother and the newborn is advisable. Maternal cervical, vaginal, and perineal lacerations must be excluded. In addition, maternal vulvar edema may be significant. Most operators institute measures such as perineal ice to ameliorate this. Pain medication is also advisable. These patients are at increased risk for hemorrhage, and a postoperative hemogram should be obtained and the condition corrected as needed.
In the absence of specific forceps-related complications, a follow-up postpartum examination within 4-6 weeks, according to the usual protocol for postpartum care, with a thorough pelvic examination, is usually sufficient.
Either mother or infant may experience complications related to a forceps-assisted delivery. Research into forceps delivery complications is hampered by a number of potential biases: Maternal and fetal complications have been reported to vary depending on skill and judgment of the operator; however, this is difficult or impossible to quantify. In addition, there is the problem of the comparison group; complication rates are often quoted in comparison to normal deliveries, but forceps deliveries are often performed in patients with complicated pregnancies or abnormal labors.
Early maternal complications include lacerations and bleeding. Even with appropriate use, forceps deliveries may be associated with an increased risk of perineal tears, [9] possibly due to the more rapid stretching of the tissues with delivery of the fetal head. One center was able to reduce the incidence of serious (third- or fourth-degree) perineal tears at operative vaginal delivery by a series of interventions. [10] The incidence of serious tears was reduced from 41% to 26% using a policy of increased use of vacuum delivery (from 16% to 29% of instrumental deliveries), use of mediolateral episiotomy, and changes in forceps technique. In addition to overt perineal tears, forceps deliveries have been associated with an increased incidence of tears of the levator ani, and this can be demonstrated by pelvic ultrasound. [11, 12]
Late maternal complications are largely related to damage to the pelvic support tissues; this damage may occur in the form of anatomic deficits, such as fistulae, or in defects in rectal sphincter function, due to both tears and nerve damage at the time of delivery. The finding of an increased risk of fecal incontinence after forceps delivery has been confirmed by numerous studies. [13] In one study, the rate of fecal incontinence was increased to 23% after an instrumental delivery (80% of these were forceps deliveries). [14]
Although urinary incontinence