Alternatively, if the lower uterine segment is thick and unyielding, cutting laterally and then slightly upward with bandage scissors will lengthen the incision. Importantly, when scissors are used, the index and midline fingers of the nondominant hand should be insinuated beneath the myometrium and above fetal parts to prevent fetal laceration. Comparing blunt and sharp expansion of the initial uterine incision, blunt stretch is associated with fewer unintended incision extensions, shorter operative time, and less blood loss. However, the rates of infection and need for transfusion do not difer (ASIClOglu, 2014; Saad, 2014).
The uterine incision is made large enough to allow delivery of the fetus without tearing into the uterine vessels that course along the lateral uterine margins. If the placenta is encountered in the incision line, it must be either detached or incised. Placental function is thereby compromised, and thus delivery is performed expeditiously.
At times, a low transverse hysterotomy is selected but provides inadequate room for delivery. In such instances, one corner of the hysterotomy incision is extended cephalad into the contractile portion of the myometrium-a J incision. If this is completed bilaterally, a U incision is formed. Last, some prefer instead to extend in the midline-a T incision. As expected, each has higher intraoperative blood loss (Boyle, 1996; Patterson, 2002). Moreover, as these extend into the contractile portion, a trial of labor is more likely to be complicated by uterine rupture in future pregnancies.
Delivey of the Fetus. In a cephalic presentation, a hand is slipped into the uterine cavity between the symphysis and fetal head. The head is elevated gently with the ingers and palm through the incision. Once the head enters the incision, delivery may be aided by modest transabdominal fundal pressure (Fig. 30-6).
After a long labor with cephalopelvic disproportion, the fetal head may be tightly wedged in the birth canal. Release of an impacted fetal head raises the risk of hysterotomy extension, of associated blood loss, and of fetal skull fracture. In
FIGURE 30-6 Delivery of the fetal head.
this situation, there are three considerations for delivery. First, a "push" method may be used. With this, upward pressure exerted by a hand in the vagina by an assistant will help to dislodge the head and allow its delivery above the symphysis.
If this is anticipated, a patient in frog-leg position may allow easier vaginal access.
Second, as an alternative, a "pull" method grasps the fetal legs to bring them through the hysterotomy. he fetus is then delivered by traction as one would complete a breech extraction.
ized trials and retrospective cohort studies (Berhan, 2014; J eve, 2016; Nooh, 2017). A low vertical hysterotomy incision, which will give more room for the "pull" technique, may be selected. If a low transverse incision has already been made, then this can be extended to a J-, U-, or T-incision as previously discussed.
The third method is use of the "fetal pillow," which is a distensible intravaginal balloon that when inflated, elevates the fetal head. The device is available outside the United States, but evidence for its eicacy is limited (Safa, 2016; Seal, 2016).
Conversely, in women without labor, the fetal head may be unmolded and without a leading cephalic point. The round head may be diicult to lift through the uterine incision in a relatively thick lower segment that is unattenuated by labor. In such instances, either forceps or a vacuum device may be used to deliver the fetal head (Fig. 30-7).