Major underestimation and overestimation of visual blood loss during cesarean deliveries: can they be predicted?

Postpartum bleeding visual underestimation: A persistent problem

Postpartum bleeding volume calculated by the visual method is lower than the bleeding volume that is objectively quantified.

Blood loss in laparoscopic distal pancreatectomy could be underestimated

BACKGROUND

Previous studies have reported that laparoscopic distal pancreatectomy (LDP) has an advantage in reducing blood loss over open distal pancreatectomy (ODP). This study was performed to investigate whether blood loss is truly reduced in LDP.

METHODS

A total of 113 patients undergoing DP from 2014 to 2022 were classified into Open and LDP groups and compared by statistical analysis. Estimated blood loss (EBL) was calculated from the perioperative changes in the hematocrit, hemoglobin, or red blood cell volume, and actual blood loss (ABL) was taken from the operative record.

RESULTS

ABL was significantly lower in the LDP than ODP group (50[5-1350] vs 335 [5-1950] ml, P < .01). However, there were no significant differences in EBL calculated from the hematocrit (406 [66-1990] vs 540 [23-1490] ml, P = .14), hemoglobin, or red blood cell volume. EBL showed more linear correlations with ABL in the ODP group (r = 0.64-0.73) than in the LDP group (r = 0.52-0.57). In the multivariate analysis for ABL, ODP (P = .02) and operative time (P < .01) were significant factors. In contrast, no significant factors were found for EBL.

CONCLUSIONS

Intraoperative blood loss may be underestimated in LDP, and a new evaluation method needs to be established.

Prevention of postpartum hemorrhage

Postpartum hemorrhage is a leading cause of severe maternal morbidity and mortality worldwide and the United States. While the rates of maternal mortality attributable to hemorrhage are declining, severe maternal morbidity continues to be a growing problem. Efforts in recent years to more appropriately identify patients at risk, define significant hemorrhage, quantify blood loss, and standardize approaches to care in pregnancy and postpartum have led to an increasing preventability of PPH. We aim to review the most current recommendation for the prevention and effective management of obstetric hemorrhage.

Towards a universal definition of postpartum hemorrhage: retrospective analysis of Chinese women after vaginal delivery or cesarean section: A case-control study

Postpartum hemorrhage (PPH) is a leading cause of maternal morbidity and mortality, yet it is inconsistently defined, preventing accurate estimation of its incidence and identification of risk factors. Here we began to explore a unified definition of PPH that may be valid for vaginal delivery and cesarean section.Medical records of women who underwent vaginal delivery or cesarean section at our tertiary medical center between January and December 2018 were retrospectively analyzed. Patients who delivered by each route were compared in terms of PPH incidence and risk factors depending on different blood loss cut-off values.A total of 560 vaginal deliveries and 393 cesarean sections were analyzed. Vaginal deliveries were associated with significantly greater blood loss based on change of hemoglobin level, but significantly lower blood loss based on clinical estimation. When PPH was defined as blood loss ≥500 ml based on change of hemoglobin level, its incidence was 57.7% for vaginal deliveries and 28.2% for cesarean sections. The corresponding incidences were 15.4% and 3.3% when PPH was defined as blood loss ≥1000 ml based on change of hemoglobin levels. Independent risk factors for PPH in vaginal deliveries were lateral perineotomy (OR 2.835, 95%CI 1.694-4.743), suturing by a junior physician (OR 3.456, 95%CI 2.005-5.956), and long time from delivery of placenta to return to the recovery room (OR 1.013, 95%CI 1.003-1.022). A risk factor for PPH in cesarean sections was a long time from delivery of the fetus until the end of the operation.PPH is a significantly underestimated obstetric problem, especially in vaginal deliveries. Regardless of delivery route, hemoglobin-based blood loss of 500 ml and 1000 ml may be useful, respectively, as early warning and diagnostic cut-off values.

Carbetocin versus Oxytocin for the Prevention of Postpartum Hemorrhage in Cesarean Deliveries: A Retrospective Study of Two Consecutive Periods

Objective  The aim of the study is to investigate whether carbetocin prevents postpartum hemorrhage (PPH) more effectively than oxytocin Methods  This historical retrospective single-center cohort study compares women who underwent cesarean deliveries during two periods. During period A, oxytocin was used as a 10-unit bolus immediately after delivery, with 20 units thereafter infused for 24 hours. During period B, carbetocin in a single 100-µg injection replaced this protocol. The main outcome was PPH, defined as a decline in hemoglobin of more than 2 g/dL after the cesarean. The analysis was performed on the overall population and then stratified by the timing of the cesareans (before or during labor). A logistic regression analysis was performed. Results  This study included 1,796 women, 52% of whom had a cesarean before labor; 15% had a PPH. The crude PPH rate was lower in period B than in period A (13 vs. 17%, respectively, odds ratio 0.75, 95% confidence interval [CI]: 0.58-0.98). The difference was no longer significant in the multivariate analysis (adjusted odds ratio: 0.81, 95% CI 0.61-1.06). Results were similar when stratified by the timing of the cesareans (before or during labor). Conclusion  Carbetocin is not superior to oxytocin in preventing PPH. However, it does provide the advantage of requiring a single injection.

The effect of meconium thickness level on neonatal outcome

BACKGROUND

Despite its prevalence and potential maternal and neonatal implications, the literature on the thickness levels of meconium stained amniotic fluid (MSAF) and its impact on neonatal outcomes is relatively outdated and relies on relatively small sample sizes.

AIMS

To study if different thickness levels of MSAF correlate with adverse neonatal outcome.

STUDY DESIGN

A retrospective cohort study.

SUBJECTS

The medical records and neonatal charts of all women with a singleton pregnancy, who underwent a trial of labor, at 37 + 0/7 weeks or beyond, between 10/2008 and 7/2018 were reviewed.

OUTCOME MEASURES

The cohort was divided according to the level of meconium reported during labor into four groups: Clear (C group), Light meconium (LM group), Intermediate meconium (IM group), and Heavy meconium (HM group). Composite neonatal outcome included at least one of the following: umbilical artery pH ≤ 7.1, sepsis, need for blood transfusion, need for phototherapy, respiratory distress syndrome, meconium aspiration syndrome, need for mechanical ventilation support, necrotizing enterocolitis, intraventricular hemorrhage, hypoxic ischemic encephalopathy, periventricular leukomalacia, seizures, hypoglycemia, hypothermia, and death. Continuous parameters were compared with Anova's test or Kruskal Wallis, and categorical variables by chi-square test or Fisher exact test, as appropriate. Multivariant logistic regression was performed in order to eliminate possible cofounders.

RESULTS

Overall, 24,445 deliveries were reviewed (C-20,185, LM-1074, IM-2736, HM-450). Composite adverse neonatal outcome was more common with increasing thickness of MSAF. On multivariable analysis, IM and HM were independently associated with composite adverse neonatal outcome.

CONCLUSION

The degree of meconium thickness independently correlates with composite adverse neonatal outcome.

Preoperative moderate thrombocytopenia is not associated with increased blood loss for low-risk cesarean section: a retrospective cohort study

BACKGROUND

The occurrence of thrombocytopenia is as high as 7-12% in pregnancy, yet minimum platelet count safe for cesarean section remains unknown.

METHODS

In this retrospective noninferior cohort study, we consecutively included patients undergoing cesarean section for a period of 6 years in a tertiary hospital and excluded patients at very high risk for excessive hemorrhage. The included patients with preoperative platelet count of 50-100 × 10⁹/L were defined as the thrombocytopenic group. The control group were eligible patients with preoperative platelet count>150 × 10⁹/L, matched to the thrombocytopenic group by age and operation timing in a 1:2 ratio. Mixed effect model was used to analyze the effect of thrombocytopenia based on a noninferiority assumption. The predefined noninferiority delta of bleeding was 50 mL.

RESULTS

There was no significant difference of the calculated blood loss between the thrombocytopenic and the control group (mean difference = 8.94, 95% CI - 28.34 mL to 46.09 mL). No statistical difference was observed in the requirement for blood transfusion, visually estimated blood loss, or the incidence of adverse events between groups. Although there were more patients admitted to intensive care unit (odds ratio = 12, 95% CI 2.69-53.62, p = 0.001) in the thrombocytopenic group, most of them required critical care for reasons other than hemorrhage. The thrombocytopenic group had longer length of hospital stay (mean difference = 0.40 days, 95% CI 0.09-0.71, p = 0.011), but the difference was considered as clinically insignificant.

CONCLUSIONS

Preoperative moderate thrombocytopenia is not associated with increased blood loss, blood transfusion, or occurrence of adverse events in patients undergoing cesarean section in absence of additional bleeding risk.

Cesarean delivery due to nonreassuring fetal heart rate: the effect of phase of labor on subsequent vaginal delivery success

Introduction: To assess trial of labor and vaginal delivery rates in pregnancies following cesarean delivery (CD) due to nonreassuring fetal heart rate (NRFHR) according to phase of labor at cesarean.Materials and methods: This was a retrospective cohort of deliveries at a university hospital between 2009 and 2016. We compared primary CDs performed due to NRFHR during nonactive labor (cervical dilatation < 5 cm) and active labor (cervical dilatation ≥ 5 cm). Subsequent deliveries were reviewed for trial of labor and vaginal delivery rates, and maternal and obstetric outcomes compared.Results: Two hundred thirty-six patients underwent a CD during the nonactive phase of labor (nonactive phase group) and 126 patients during the active phase of labor (active phase group). Patients with a past active phase CD were more likely to attempt a trial of labor but equally likely to achieve a vaginal delivery. There was a trend for more CDs due to nonprogressive labor in this group. After adjustment, only past vaginal delivery was independently associated with a successful vaginal delivery, but not the phase of labor during which the past CD was performed.Conclusion: Our study points to a similar prognosis for patients with a past CD due to NRFHR, regardless of previous labor course.

Meconium-stained amniotic fluid: a risk factor for postpartum hemorrhage

Background/aim

Clinical data with respect to the impact of meconium on the risk of maternal hemorrhage are scarce. Therefore, in this study, we aimed to determine whether meconium-stained amniotic fluid (MSAF) represents a risk factor for postpartum hemorrhage (PPH) after vaginal delivery in a large unselected population.

Patients and methods

A retrospective cohort study evaluated 78,542 consecutive women who had a vaginal delivery between 24th and 44th weeks of gestation. The women who had undergone cesarean section were excluded to avoid possible bias. Postpartum blood loss was measured with graduated blood sack. Postpartum blood loss between 1,000 and 2,000 mL and >2,000 mL were classified as moderate and severe PPH, respectively.

Results

A total of 74,144 patients were available for analysis. According to the color of amniotic fluid (AF), two groups of patients were identified: MSAF (n=10,997) and clear AF (n=63,147). The rates of severe and massive PPH were found to be significantly higher in the MSAF group than that of clear AF group (OR=1.3, 95% CI: 1.2-1.5, p<0.001 and OR=2.5, 95% CI: 1.5-4.2, p<0.001). Operative vaginal delivery rate was found to be higher in the MSAF group than that of clear AF group, but the difference was only borderline significant (OR=1.5, 95% CI: 1.0-2.2, p=0.05). There were no significant differences between the MSAF and the clear AF groups with respect to episiotomies, second- or third-degree perineal tears, vaginal-perineal thrombus, cervical lacerations, vaginal births after cesarean section, twin deliveries, and placental retention rates.

Conclusion

To the best of our knowledge, this is the first clinical study that has investigated the role of MSAF as a risk factor for PPH after vaginal delivery in an unselected population. Our results suggest that MSAF is significantly associated with higher risk of moderate and severe PPH than clear AF.