Intra-operative haemorrhage by blunt versus sharp expansion of the uterine incision at caesarean delivery: a randomised clinical trial

Abstract

Objective To determine whether the method used to expand the uterine incision for caesarean delivery affects the incidence of intra-operative haemorrhage. Design A prospective randomised study of women undergoing a low segment transverse caesarean delivery.Participants were assigned to have their uterine incision either sharply or bluntly expanded. Participants Between June 1998 and June 2000, 470 women drew assignments to the sharp expansion group and 475 to the blunt group. Results The maternal demographics of age, race, nulliparity, and body mass index as well as pre-operative haematocrit were similar between groups. Compared with the blunt group, the estimated blood loss (886 versus 843mL, P ¼ 0.001), change in the mean haematocrit (6.1% versus 5.5%, P ¼ 0.003), incidence of postpartum haemorrhage (13% versus 9%; relative risk ¼ 1.23, 95% CI 1.03, 1.46) and need for a transfusion (2% versus 0.4%; relative risk ¼ 1.65, 95% CI 1.25, 2.21) were significantly greater in the sharp group. Conclusion In caesarean delivery, sharply expanding the uterine incision significantly increases intra-operative blood loss and the need for subsequent transfusion.

Unintended Extension of the Lower Segment Uterine Incision at Cesarean Delivery: A Randomized Comparison of Sharp versus Blunt Techniques

“…18,19 The only difference between the two groups was the technique for expanding the uterine incision (sharp vs. blunt). We found that unintended extension of the uterine incision was significantly less frequent when using the blunt technique than the sharp technique, similar to the findings of Magann et al 12 Furthermore, there was significantly less estimated blood loss after elective CS using the blunt technique compared with the sharp technique, similar to previous results. 12,13 Our results do not agree with those of Hameed and Ali.…”

“…9 Expansion of the uterine incision either bluntly or with scissors has been evaluated only in five randomized controlled trials. [10][11][12][13][14] Two of these studies reported no difference between the uterine expansion methods with respect to a postoperative decrease in maternal hemoglobin and hematocrit, 10,11 while the remaining two studies showed that expanding the uterine incision with a sharp object significantly increased the intraoperative blood loss. 12,13 By contrast, Hameed and Ali reported that the sharp method of expanding the uterine incision during cesarean deliveries was more precise and resulted in less blood loss and fewer inadvertent tears compared with the blunt method.…”

Complications of blunt versus sharp expansion of the uterine incision in lower segment caesarean section. A randomized controlled trial

“…The other important outcome that has to be considered when comparing the blunt expansion and sharp expansion of the uterine incision is the estimated blood loss in either technique. It has been argued that sharp expansion method is associated with higher blood loss due to bleeding from incision itself by muscle ooze or traumatized vasculature [10]. In our study we did not find a significant difference of the percentage blood loss between sharp uterine expansion group and the blunt uterine expansion group.…”

“…Here there was no significant difference in the incidence of unintended uterine incisions, intra operative duration or estimated blood loss [9]. In another study, which included 945 women, it was reported that sharp extension is associated with greater estimated blood loss and a greater incidence of post-partum haemorrhage and need for transfusion [10]. On the other hand a non-randomized clinical trial Original PaPers www.slcog.lk/sljog in Pakistan on comparison of blunt vs. sharp expansion of the uterine incision reported a significant increase in blood loss, need for transfusion and inadvertent extension of incision in the blunt group compared to sharp group [11].…”

“…It was determined that 250 women in each group was sufficient power (power of 0.80, α error of 0.05 & β error =0.20) to demonstrate a difference of 10% (25%vs15%) of unintended tears between groups [12]. These calculations were based on a previous study in which the unintended extensions between the two methods were approximately 25% versus 15% [10] but an interim analysis was done halfway through the study after recruiting 274 participants which included 133 in the sharp expansion group and 141 in blunt expansion group who underwent through the complete trial. Here we found that the percentage of unintended extensions, which was our primary outcome measure, was significantly higher in the blunt expansion group compared to the sharp expansion group.…”