Blunt versus sharp uterine incision expansion during low transverse cesarean delivery: a metaanalysis

Understanding Obstetrical Surgical Planning for the Pediatrician

Cesarean deliveries are common in the United States, occurring in approximately one-third of deliveries in 2021. Given this high rate of cesarean deliveries, it is important for all clinicians caring for the pregnant person-infant dyad to be educated about cesarean deliveries. In this review, we describe the indications for cesarean delivery, the evidence-based practices of preoperative planning to ensure safe deliveries, and the clinical decision-making behind various cesarean incisions. In addition, we discuss the most common complications of cesarean deliveries for the pregnant person-infant dyad.

Evidence-based surgical procedures to optimize caesarean outcomes: an overview of systematic reviews

Background

Caesarean section (CS) is the most performed major surgery worldwide. Surgical techniques used for CS vary widely and there is no internationally accepted standardization. We conducted an overview of systematic reviews (SR) of randomized controlled trials (RCT) to summarize the evidence on surgical techniques or procedures related to CS.

Methods

Searches were conducted from database inception to 31 January 2024 in Cochrane Database of Systematic Reviews, PubMed, EMBASE, Lilacs and CINAHL without date or language restrictions. AMSTAR 2 and GRADE were used to assess the methodological quality of the SRs and the certainty of evidence at outcome level, respectively. We classified each procedure-outcome pair into one of eight categories according to effect estimates and certainty of evidence. The overview was registered at PROSPERO (CRD 42023208306).

Findings

The analysis included 38 SRs (16 Cochrane and 22 non-Cochrane) published between 2004-2024 involving 628 RCT with a total of 190,349 participants. Most reviews were of low or critically low quality (AMSTAR 2). The SRs presented 345 procedure-outcome comparisons (237 procedure versus procedure, 108 procedure versus no treatment/placebo). There was insufficient or inconclusive evidence for 256 comparisons, clear evidence of benefit for 40, possible benefit for 17, no difference of effect for 13, clear evidence of harm for 14, and possible harm for 5. We found no SRs for 7 pre-defined procedures. Skin cleansing with chlorhexidine, Joel-Cohen-based abdominal incision, uterine incision with blunt dissection and cephalad-caudal expansion, cord traction for placental extraction, manual cervical dilatation in pre-labour CS, changing gloves, chromic catgut suture for uterine closure, non-closure of the peritoneum, closure of subcutaneous tissue, and negative pressure wound therapy are procedures associated with benefits for relevant outcomes.

Interpretation

Current evidence suggests that several CS surgical procedures improve outcomes but also reveals a lack of or inconclusive evidence for many commonly used procedures. There is an urgent need for evidence-based guidelines standardizing techniques for CS, and trials to fill existing knowledge gaps.

Funding

UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), a cosponsored programme executed by the World Health Organization (WHO).

Unintended uterine extension at the time of cesarean delivery - risk factors and associated adverse maternal and neonatal outcomes

OBJECTIVE

To identify risk factors, maternal and neonatal adverse outcomes related to unintended lower segment uterine extension during cesarean delivery (CD).

METHODS

A retrospective cohort analysis in a single, university-affiliated medical center between 1 January 2018 and 31 December 2019. All singleton pregnancies delivered by CD were included. Univariate and multivariate analyses were performed to identify maternal and obstetrical predictors for uterine extension during CD. For secondary outcomes, we assessed the correlation between uterine extension and any adverse maternal or neonatal outcome. Risk factors were analyzed using ROC statistics to measure their prediction performance for a uterine extension.

RESULTS

Overall, 1746 (19.3%) CDs were performed during the study period. Of them, 121 (6.9%) CDs were complicated by unintended uterine extension. There was no difference in maternal demographics and clinical data stratified by uterine extension at CD. Uterine extensions were significantly more common following induction of labor, intrapartum fever, premature rupture of membranes, a trial of labor after cesarean, advanced gestational age, emergent CD, and in particular CD during the second stage of labor (37.2% vs. 6.5%) and after failed vacuum extraction (6.6% vs. 1.1%), p < .05 for all. The incidence of postpartum hemorrhage and re-laparotomy did not differ between the groups. Most of the extensions were caudal-directed (40.4%), and were closed by a two-layer closure (92%). Mean extension size was 4.5 ± 1.7 cm. Using multivariable analysis, the only factor that remained significant was CD at the second stage of labor (adjusted odds ratio (aOR) 54.2, 95% CI 4.5-648.9, p = .002), with an area under the ROC curve 0.653 (95% CI 0.595-0.712, p < .001). Emergent CD, body mass index, birth weight, failed vacuum attempt, and trial of labor after cesarean were not significant. For secondary outcomes, an unintended uterine extension was associated with longer operation time, higher estimated blood loss, greater pre- to post-CD hemoglobin difference, increased blood products transfusion, puerperal fever, and longer hospital stay. No clinically significant neonatal adverse outcomes were observed.

CONCLUSIONS

In our cohort, second-stage CD was the strongest predictor for an unintended uterine extension. Following uterine extension, women had increased infectious and blood-loss morbidity.

[The cesarean procedure: Guidelines for clinical practice from the French College of Obstetricians and Gynecologists]

OBJECTIVE

To identify procedures to reduce maternal morbidity during cesarean.

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE® method with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane and EMBASE databases. The quality of the evidence was assessed (high, moderate, low, very low) and a (i) strong or (ii) weak recommendations or (iii) no recommendation were formulated. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Of the 27 questions, there was agreement between the working group and the external reviewers on 26. The level of evidence of the literature was insufficient to provide a recommendation on 15 questions. Preventing hypothermia is recommended to increase maternal satisfaction and comfort (weak recommendation) and to reduce neonatal hypothermia (strong recommendation). The quality of the evidence of the literature did not allow to recommend the skin disinfectant to be used nor the relevance of a preoperative vaginal disinfection nor the choice between the use or nonuse of an indwelling bladder catheterization (if micturition takes place 1 hour before the cesarean section). The Misgav-Ladach technique or its analogues should be considered rather than the Pfannenstiel technique to reduce maternal morbidity (weak recommendation) bladder flap before uterine incision should not be performed routinely (weak recommendation), but a blunt (weak recommendation) and cephalad-caudad extension of uterine incision (weak recommendation) should be considered to reduce maternal morbidity. Antibiotic prophylaxis is recommended to reduce maternal infectious morbidity (strong recommendation) without recommendation on its type or the timing of administration (before incision or after cord clamping). The administration of carbetocin after cord clamping does not significantly decrease the incidence of blood loss>1000 ml, anemia, or blood transfusion compared with the administration of oxytocin. Thus, it is not recommended to use carbetocin rather than oxytocin in cesarean. It is recommended that systematic manual removal of the placenta not to be performed (weak recommendation). An antiemetic should be administered after cord clamping in women having a planned cesarean under locoregional anaesthesia to reduce intraoperative and postoperative nausea and vomiting (strong recommendation) with no recommendation regarding choice of use one or two antiemetics. The level of evidence of the literature was insufficient to provide any recommendation concerning single or double-layer closure of the uterine incision, or the uterine exteriorization. Closing the peritoneum (visceral or parietal) should not be considered (weak recommendation). The quality of the evidence of the literature was not sufficient to provide recommendation on systematic subcutaneous closure, including in obese or overweight patients, or the use of subcuticular suture in obese or overweight patients. The use of subcuticular suture in comparison with skin closure by staples was not considered as a recommendation due to the absence of a consensus in the external review rounds.

CONCLUSION

In case of cesarean, preventing hypothermia, administering antiemetic and antibiotic prophylaxis after cord clamping are the only strong recommendations. The Misgav-Ladach technique, the way of performing uterine incision (no systematic bladder flap, blunt cephalad-caudad extension), not performing routine manual removal of the placenta nor closure of the peritoneum are weak recommendations and may reduce maternal morbidity.

Sharp expansion of the cesarean delivery uterine incision in women with previous cesarean section scars

Although the blunt uterine incision expansion during a low-transverse cesarean delivery has prevailed over the sharp technique, the latter should not be completely abandoned. The sharp method with scissors should be considered when managing patients with previous cesarean sections, although more studies are required for a definite answer.

Risk factors for uterine incision extension during cesarean delivery

BACKGROUND

Unintentional extension of uterine incision is a known complication during cesarean delivery estimated to occur in 4-8% of cesarean deliveries. The aim of this study was to examine risk factors associated with unintentional uterine incision extension and to assess which of them are independent risk factors for this condition.

STUDY DESIGN

We conducted a retrospective cohort study at a large public university tertiary referral center between 2003 and 2017. Included were women who underwent cesarean delivery during this time period. Demographic, medical, obstetrical and surgical data were collected. The primary outcome was the presence of uterine incision extension during cesarean delivery. Secondary outcomes included detection of risk factors associated with uterine incision extension. A multivariate analysis was additionally performed to identify general and labor related risk factors for unintentional extension of uterine incision among patients that underwent cesarean delivery during second stage of labor.

RESULTS

During the study period, 25,879 cesarean deliveries performed in our medical center were assessed. Out of them, 731 (2.8%) cases of unintended uterine incision extension were identified. Women in this group had high rates of full cervical dilatation and increased maternal hemorrhage. Assessment of incision extension direction revealed that two-thirds of extensions were lateral, mostly unilateral. Median size of the extension was 2.7 ± 1.2 cm.Independent parameters associated with unintended uterine incision extension included nulliparity, vertex presentation, epidural anesthesia and cesarean section indication. Further analysis including cesarean deliveries performed during the second stage of labor revealed 397 (15.3%) cesarean deliveries in which incision extension was noted and 2205 (84.7%) cesarean deliveries without incision extension. Following multivariate analysis performed in women who underwent cesarean delivery during second stage of labor, two independent parameters associated with unintended uterine incision extension remained significant - past cesarean delivery and failed vacuum attempt.

CONCLUSIONS

Vacuum extraction attempt and previous cesarean delivery are independent risk factors for uterine incision extension in women undergoing cesarean delivery during the second stage of labor. We also showed the majority of these extensions to be lateral.

Comparison of intra operative hemorrhage by blunt and sharp expansion of uterine incision at cesarean section

Objectives:

To compare the effect of blunt and sharp incision of uterus at cesarean section on intra-operative haemorrhage.

Methods:

This trial was conducted at the Department of Obstetrics and Gynaecology, Pakistan Ordinance Factory Hospital, Wah Cantt from 14^th January to 13^th July 2012. Total 80 women planned for lower segment cesarean section through Pfannensteil incision were randomized to either blunt uterine incision (Group-A, n=40) or sharp uterine incision (Group-B, n=40). The fall in Haemoglobin and HCT was compared in two groups and analyzed with help of SPSS version 10.

Results:

Both groups were similar in terms of demographic features like age, parity, gestational age and indication for cesarean section. The participants in Group-A reveled significantly less drop of mean Hb concentration as compared to Group-B (1.47±1.08 and 1.95±0.85 respectively, P value 0.031). Similarly, the fall in mean HCT was significantly less in Group-A in comparison to Group-B (3.21±1.3 and 4.21±2.17 respectively, P-value 0.015)

Conclusion:

Blunt expansion of uterine incision during caesarean section is associated with less fall in Haemoglobin and HCT as compared to sharp expansion.

Cesarean delivery: an evidence-based review of the technique

The cesarean section is utilized to deliver babies since the late 19^th century. Nowadays, the frequency of cesarean section is increased, mainly because of the low rate of complications and for the increasing demand from future mothers, scared by the idea of painful labor. Although the technique to perform cesarean section has been refined over time, infections, hemorrhage, pain and other consequences still represent matter of debate. To try to reduce the incidence of these complications many trials, randomized or not, have been performed, with the aim to analyze different technical aspects of this surgery. The aim of our review was to resume all the evidence-based instructions on how to best approach to cesarean section practice, in a step-to-step fashion, considering pre-operative actions, opening and closing steps, and postoperative prophylaxis.

The Case for Standardizing Cesarean Delivery Technique: Seeing the Forest for the Trees

In this Commentary, we explain the case for a standardized cesarean delivery surgical technique. There are three strong arguments for a standardized approach to cesarean delivery, the most common major abdominal surgery performed in the world. First, standardization within institutions improves safety, efficiency, and effectiveness in health care delivery. Second, surgical training among obstetrics and gynecology residents would become more consistent across hospitals and regions, and proficiency in performing cesarean delivery measurable. Finally, standardization would strengthen future trials of cesarean delivery technique by minimizing the potential for aspects of the surgery which are not being studied to bias results. Before 2013, more than 155 randomized controlled trials, meta-analyses or systematic reviews were published comparing various aspects of cesarean delivery surgical technique. Since 2013, an additional 216 similar studies have strengthened those recommendations and offered evidence to recommend additional cesarean delivery techniques. However, this amount of cesarean delivery technique data creates a forest for the trees problem, making it difficult for a clinician to synthesize this volume of data. In response to this difficulty, we propose a comprehensive, evidence-based and standardized approach to cesarean delivery technique.

Endometrium-free uterine closure technique and abnormal placental implantation in subsequent pregnancies

BACKGROUND

Abnormal placentation can result in massive hemorrhage, which is the leading cause of severe maternal morbidities and mortality in its management. Over the past 50 years, the incidence of placenta previa (PP), abnormal implantation of the placenta, and cesarean scar pregnancy have continued to rise. This coincides with the well-documented parallel rise in the rate of cesarean deliveries, the performance of multiple repeat cesarean deliveries and the adoption of newer uterine closure techniques. However, no studies have examined the role of uterine closure techniques in abnormal placentation in women with a history of a prior cesarean delivery.

OBJECTIVE

To assess the practicality of one specific uterine closure technique at cesarean delivery and to evaluate the relationship between previous cesarean delivery and subsequent development of abnormal implantation of the placenta, as well as neonatal and other perioperative outcomes after receiving an endometrium-free uterine closure technique.

METHODS

This retrospective observational study considered cesarean deliveries (n = 727) and subsequent vaginal births after cesarean delivery (n = 109) among total deliveries (n = 4496) performed in private practice at NYU Langone Health from 1985 to 2015. All cesarean deliveries were performed using the endometrium-free uterine closure technique. The primary outcome was the incidence of abnormal implantation of the placenta in subsequent pregnancies. The secondary outcomes were neonatal and maternal complications, specifically postoperative hemoglobin and hematocrit concentration losses. The association between independent variables and outcomes were evaluated using mixed-effect regression models.

RESULTS

In contrast to published data, independent of the number of repeat cesarean deliveries, the presence of 26 (3.1%) PPs and of 366 (43.8%) anterior placentas, there were no patients with abnormal implantation of the placenta in a cesarean scar, neither prenatally nor at delivery. Maternal hemorrhage, postoperative and neonatal complications did not reach clinical significance. The statistical analysis revealed that, when compared with women who had fewer repeat cesarean deliveries using endometrium-free uterine closure technique, those with the most had a lesser risk of forming PP and less blood loss, as measured by both hematocrit and hemoglobin evaluation.

CONCLUSION

In this retrospective cohort study, the exclusion of the endometrium during the endometrium-free uterine closure technique was associated with fewer placental abnormalities in subsequent pregnancies and reduced life-threatening maternal morbidity for future cesarean deliveries.

Guidelines for intraoperative care in cesarean delivery: Enhanced Recovery After Surgery Society Recommendations (Part 2)

The Enhanced Recovery After Surgery Society guideline for intraoperative care in cesarean delivery will provide best practice, evidenced-based, recommendations for intraoperative care, with primarily a maternal focus. The "focused" pathway process for scheduled and unscheduled cesarean delivery for this Enhanced Recovery After Surgery cesarean delivery guideline will consider procedure from the decision to operate (starting with the 30-60 minutes before skin incision) through the surgery. The literature search (1966-2017) used Embase and PubMed to search medical subject headings including "cesarean section," "cesarean section," "cesarean section delivery," and all pre- and intraoperative Enhanced Recovery After Surgery items. Study selection allowed titles and abstracts to be screened by individual reviewers to identify potentially relevant articles. Metaanalyses, systematic reviews, randomized controlled studies, nonrandomized controlled studies, reviews, and case series were considered for each individual topic. Quality assessment and data analyses evaluated the quality of evidence and recommendations were evaluated according to the Grading of Recommendations, Assessment, Development and Evaluation system as used and described in previous Enhanced Recovery After Surgery Society guidelines. The Enhanced Recovery After Surgery cesarean delivery guideline/pathway has created a maternal focused pathway (for scheduled and unscheduled surgery starting from 30-60 minutes before skin incision to maternal discharge) with Enhanced Recovery After Surgery-directed preoperative elements, intraoperative elements, and postoperative elements. Specifics of the intraoperative care included the use of prophylactic antibiotics before the cesarean delivery, appropriate patient warming intraoperatively, blunt expansion of the transverse uterine hysterotomy, skin closure with subcuticular sutures, and delayed cord clamping. A number of specific elements of intraoperative care of women who undergo cesarean delivery are recommended based on the evidence. The Enhanced Recovery After Surgery Society guideline for intraoperative care in cesarean delivery will provide best practice, evidenced-based, recommendations for intraoperative care with primarily a maternal focus. When the cesarean delivery pathway (elements/processes) is studied, implemented, audited, evaluated, and optimized by maternity care teams, this will create an opportunity for the focused and optimized areas of care and recommendations to be further enhanced.

Postcesarean wound infection: prevalence, impact, prevention, and management challenges

Surgical site infection (SSI) is one of the most common complications following cesarean section, and has an incidence of 3%-15%. It places physical and emotional burdens on the mother herself and a significant financial burden on the health care system. Moreover, SSI is associated with a maternal mortality rate of up to 3%. With the global increase in cesarean section rate, it is expected that the occurrence of SSI will increase in parallel, hence its clinical significance. Given its substantial implications, recognizing the consequences and developing strategies to diagnose, prevent, and treat SSI are essential for reducing postcesarean morbidity and mortality. Optimization of maternal comorbidities, appropriate antibiotic prophylaxis, and evidence-based surgical techniques are some of the practices proven to be effective in reducing the incidence of SSI. In this review, we describe the biological mechanism of SSI and risk factors for its occurrence and summarize recent key clinical trials investigating preoperative, intraoperative, and postoperative practices to reduce SSI incidence. It is prudent that the surgical team who perform cesarean sections be familiar with these practices and apply them as needed to minimize maternal morbidity and mortality related to SSI.