http://informahealthcare.com/jmf ISSN: 1476-7058 (print), 1476-4954 (electronic) J Matern Fetal Neonatal Med, 2015; 28(7): 839–841 ! 2014 Informa UK Ltd. DOI: 10.3109/14767058.2014.935326
SHORT REPORT
Is manual palpation of the uterine scar following vaginal birth after cesarean section (VBAC) helpful? C. Dinglas, T. J. Rafael, and A. Vintzileos Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Winthrop University Hospital, Mineola, NY, USA
Abstract
Keywords
Risk of uterine rupture with trial of labor after cesarean (TOLAC) is less than one percent. Discovery of uterine rupture often occurs during labor. In our case, the uterine scar is discovered to be ruptured during the postpartum period. The exact cause and time of uterine rupture is difficult to ascertain in this case, yet manual palpation of the uterine scar did not aid in the eventual diagnosis.
TOLAC, uterine exploration, uterine rupture, VBAC
Introduction Uterine rupture is a life-threatening complication for women undergoing trial of labor after cesarean delivery (TOLAC). The initial signs and symptoms of uterine rupture are typically nonspecific, which makes the diagnosis difficult and can delay definitive therapy. Fetal heart rate abnormalities, worsening abdominal pain, vaginal bleeding, and hemodynamic instability raise the suspicion of uterine rupture [1,2]. The diagnosis of uterine rupture can be clinical or radiological and is based on the complete disruption of all uterine layers, including the serosa. Typically, the most common indicator for diagnosis of uterine rupture is based on fetal distress in women who are at risk for uterine rupture [2]. Studies have suggested that manual uterine exploration may be performed in symptomatic patients following vaginal delivery, including those with suprapubic pain, persistent vaginal bleeding, retained placenta or in patients with risk factors (i.e. prolonged second stage, operative delivery) [3,4]. If uterine massage is necessitated postpartum, we must evaluate the clinical utility of manual scar palpation.
Case A 23-year-old African American female G2P1001 at 40 weeks gestation was admitted with premature rupture of
Address for correspondence: Dr. Cheryl Dinglas, Division of MaternalFetal Medicine, Department of Obstetrics and Gynecology, Winthrop University Hospital, 259 1st Street, Mineola, NY 11501, USA. E-mail:
[email protected] History Received 27 March 2014 Revised 29 May 2014 Accepted 12 June 2014 Published online 11 July 2014
membranes, and desired a trial of labor after cesarean section. Her previous C-section was for a non-reassuring fetal heart rate tracing 3 years prior. The operative report indicated that she had a 2-layer closure of a low transverse uterine incision. With this history, the patient was deemed an appropriate candidate for TOLAC. The patient was admitted at 1 cm dilation and progressed to full dilation in approximately 18 hours with the use of low-dose Pitocin to a maximum of 18 milliunits/min. During the patient’s labor course, the patient remained comfortable with an epidural. The fetal heart tracing during the labor course demonstrated persistent, but intermittent variable decelerations resolved with resuscitative efforts, including lateral positioning, oxygen, and an amnioinfusion. The amnioinfusion was given as a bolus of 500 ml over 30 min. Five minutes prior to completion of the bolus, the patient was found to be fully dilated. Then, the second stage of labor lasted 35 min. The patient vaginally delivered a live female infant, weighing 7 pounds, 12 ounces. The placenta delivered spontaneously was intact. Afterwards, the vagina, perineum and cervix were thoroughly explored with only a small periurethral laceration identified. Excellent hemostasis was noted and no repair was needed. After few minutes, vaginal bleeding was seen. Upon further examination of the genital tract, moderate bleeding was noticed from the uterus, which was found to be atonic. An examination of the prior uterine scar was performed and found to be intact by both the resident and attending physician. Subsequently, uterine massage was performed using the bimanual technique and the patient received an additional 20 units of Pitocin plus an IM injection of Methergine 0.2 mg. The uterus regained tone and the
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vaginal bleeding was ceased. The patient’s vitals were found to be normal. The uterine scar was not reexamined after the bimanual examination. The physicians left the room and allowed the mother to bond with her newborn. Approximately 15 minutes later, the patient complained of severe abdominal pain and the physicians returned to the room for reevaluation. She described the pain as diffuse, and the abdomen was found to be distended with guarding. Her heart rate was 130 and her blood pressure dropped to 75/41. A bedside ultrasound scan demonstrated hemoperitoneum. The patient was taken back to the operating room where exploratory laparotomy revealed a full thickness tear along the previous low transverse scar, which was actively bleeding. Approximately 1500 cc of hemoperitoneum was evacuated and the patient received 4 units of packed red blood cells and 2 units of fresh frozen plasma in the OR. The patient received an additional 2 units of packed red blood cells postoperatively and was discharged home in stable condition on postoperative day #5.
Comment The overall incidence in women with a prior cesarean delivery is reported to be less than 1% [5]. The risk of uterine rupture depends on several factors. Risk factors include a prior cesarean section, with increasing risk with more than one C-section, use of high dose Pitocin, fundal pressure, increasing maternal age, advanced gestational age, birth weight exceeding 4000 g, inter-delivery interval 518–24 months, high parity, frequent epidural dosing, and singlelayer uterine closure. Several models have been developed to identify patients at higher risk for uterine rupture based on these risk factors [6,7]. In our case, the patient would be classified as low-risk. She only had one previous Cesarean section which occurred 3 years prior, and had a transverse incision that was repaired in two layers. Also, the patient was young and her labor course involved low-dose Pitocin, never exceeding beyond an infusion of 18 milliunits/min. Additionally, she delivered an infant that weighed less than 4000 g. Concern for uterine rupture during the patient’s labor course occurred when intermittent variable decelerations were noted on fetal heart rate monitoring. However, these decelerations responded well to maternal resuscitative efforts, including an amnioinfusion. Yet, it is important to consider whether the amnioinfusion could have caused or contributed to the uterine rupture. Amnioinfusion results in a large volume expansion of the uterus and could potentially weaken the old uterine scar. It is less likely in this case since the amnioinfusion was initiated just 30 min prior to delivery with little time to infuse large volumes of fluid. Also, the decelerations resolved with the amnioinfusion instead of causing a non-reassuring fetal heart rate tracing, as we might expect with uterine rupture. An uncomplicated vaginal delivery appeared to have occurred in which the patient was found to have only a small periurethral laceration that was hemostatic. However, uterine rupture was discovered within the following 20 min after delivery. The cause of rupture might be attributed to
J Matern Fetal Neonatal Med, 2015; 28(7): 839–841
uterine exploration since the old uterine scar was identified to be intact by two physicians just prior to the uterine massage that was utilized to resolve the atony. Additionally, the patient developed a sudden change in pain shortly after the physicians left the room, which was just after the uterus firmed and vaginal bleeding had ceased. Conversely, the scar may have ruptured during the antepartum time period, with the physicians’ perceptions of an intact scar on postpartum evaluation being inaccurate. Some clinicians recommend routine uterine scar exploration after an uncomplicated VBAC, while others only recommend it in situations of excessive vaginal bleeding or signs of hypovolemia [7,8]. In this patient, the cervix and vagina were reexamined after bleeding was noted and was seen to come from the uterus. The risk of hemorrhage was taken into consideration. With vaginal bleeding after successful TOLAC, clinicians might suspect possible uterine scar dehiscence versus complete rupture. Thus, palpation of the uterine scar was performed in this patient. In this case, it is plausible that the myometrial fibers could have gradually stretched throughout the patient’s labor course, and a small defect could have been present at the time of uterine exploration with palpation causing further insult to the defect. It is also possible the uterine scar could have been affected by a combination of factors in which it became thin enough during labor on Pitocin, amnioinfusion, delivery, and then ruptured as a result of the uterine massage. It is important to note that caution should be taken when performing uterine massage in cases of VBAC. In either case, manual palpation of the scar was not helpful; as a matter of fact it could have contributed to the complete rupture. One study by Silberstein et al. demonstrated that when the integrity of the uterine scar is palpated in patients achieving successful VBAC, the detection rate of uterine scar dehiscence or rupture was 0.23%. Furthermore, less than 0.005% of the subjects had complete uterine rupture. Thus, it appears that the potential benefit, if any, of routine examination of uterine scar after VBAC is low [9]. The decision to palpate the uterine scar should be reevaluated. According to ACOG, manual uterine exploration after VBAC has not been shown to improve outcomes [7]. Additional methods could be considered in evaluating the integrity of the uterine scar, including ultrasound [10]. Also, medical management to control bleeding could be quickly utilized rather than uterine massage in patients with a vulnerable C-section scar. More prospective analyses on TOLAC should examine the clinical utility of manual uterine scar exploration following successful VBAC.
Declaration of interest The authors report no declarations of interests.
References 1. Bujold E, Gauthier RJ. Neonatal morbidity associated with uterine rupture: what are the risk factors? Am J Obstetr Gynecol 2002;186: 311–14. 2. Holmgren CM. Uterine rupture associated with VBAC. Clin Obstetr Gynecol 2012;55:978–87.
DOI: 10.3109/14767058.2014.935326
3. Lurie S, Hagay Z, Goldschmit R, Insler V. Routine previous cesarean scar exploration following successful vaginal delivery. Is it necessary? Eur J Obstetr Gynecol Reprod Biol 1992;45: 185–6. 4. Perrotin F, Marret H, Fignon A, et al. Scarred uterus: is routine exploration of the cesarean scar after vaginal birth always necessary? J Gynecol Obstetr Biol Reprod 1999;28:253–62. 5. Guise JM, Denman MA, Emeis C, et al. Vaginal birth after cesarean: new insights on maternal and neonatal outcomes. Obstetr Gynecol 2010;115:1267–8. 6. Murphy, DJ. Uterine rupture. Curr Opin Obstetr Gynecol 2006;18: 135–40. 7. American College of Obstetricians and Gynecologists (ACOG). ACOG Practice bulletin no. 115: Vaginal birth
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after previous cesarean delivery. Obstet Gynecol 2010; 116:450–63. 8. Landon MB. Predicting uterine rupture in women undergoing trial of labor after prior cesarean delivery. Semin Perinatol 2010;34: 267–71. 9. Silberstein T, Wiznitzer A, Katz M, et al. Routine revision of uterine scar after cesarean section: has it ever been necessary? Eur J Obstetr Gynecol Reprod Biol 1998;78: 29–32. 10. Rozenberg P, Fracois G, Philippe HJ, et al. Thickness of the lower uterine segment: its influence in the management of patients with previous cesarean sections. Eur J Obstetr Gynecol Reprod Biol 1999;87:39–45.
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