Knotless Barbed Suture Closure of the Uterus at Caesarean Section

Caesarean section (CS) is one of the most commonly performed operations worldwide and the prevalence is increasing1. There are perioperative complications including neonatal morbidity and, on the maternal side, haemorrhage, infection and organ injury2. Furthermore, there are implications for future pregnancies, the risks of which rise with each successive caesarean3. Closure of the lower segment hysterotomy at CS is most commonly affected using a 2-layer approach employing braided absorbable sutures such as Vicryl (polyglactin 910)4. Closure is with a continuous suturing technique and the tension of the closure is maintained manually until the suture is secured with knots at the angles. Knotless barbed suture (KBS) closure of the caesarean hysterotomy remains a novel technique that is not yet widely employed. These sutures, first invented in 1964, were approved by the FDA in 2004 and were first used in a clinical trial in 20075. Barbed sutures anchor themselves within the tissue, as barbs on the suture resist backward movement through the tissue. They offer even tension over the length of the hysterotomy and are cut flush with the uterus without the need for anchoring knots.

A systematic review and meta-analysis of randomised control trials (n460) on KBS compared with 'smooth' sutures at elective CS found that operative times were lower and the need for additional haemostatic sutures was lower6. There was a trend towards lower blood loss and no difference in operative morbidity. Some trials, some of which are ongoing, have examined whether there is a difference in lower segment residual myometrial thickness (RMT) after KBS and whether there is a difference in the incidence of scar niche7. These outcomes, respectively, are offered as potential proxy measures for uterine rupture risk and praevia or PAS risk. The results of these trials, as per their proxy outcomes, have been encouraging. This trial offers the first data on KBS at CS in UK practise.

Methods:

This single-centre retrospective cohort study in a tertiary care hospital in Northern England including caesarean deliveries from November 2022 to October 2024 - a 24 month period. The cohorts are women who had a Medtronic's V-loc 180 absorbable device (KBS) and women who had 2 layer vicryl (polyglactin 910) uterine closure i.e. smooth suture (SS).

Data was collected prospectively using a Microsoft Excel™ spreadsheet by the lead clinician (HS) as part of a quality improvement project and data was cross-referenced with patient records using Clevermed badgernotes ™ maternity system data records. Baseline characteristics reported are: patient age at delivery, parity, number of previous caesarean sections, BMI at booking, additional intraoperative interventions, birth-weight, indication for, and category of, caesarean, mode of anaesthesia, grade of operator and whether a consultant was present if not the primary surgeon (Table 1). The pre-specified outcome was blood loss. The pre-specified secondary outcomes were operating time, infection rates, readmission, unplanned outpatient attendance, and other complications.