Association between ionised calcium and severity of postpartum haemorrhage: a retrospective cohort study

Postpartum Hemorrhagic Morbidity with Scheduled versus Unscheduled Cesarean Delivery at Term

OBJECTIVE

 This study aimed to compare the composite maternal hemorrhagic outcomes (CMHOs) among term (≥37 weeks) singletons who had scheduled versus unscheduled cesarean deliveries (CDs). A subgroup analysis was done for those without prior uterine surgeries.

STUDY DESIGN

 Retrospectively, we identified all singletons at term who had CDs. The unscheduled CDs included individuals admitted with a plan for vaginal delivery with at least 1 hour of attempted labor. CMHOs included any of the following: estimated blood loss of ≥1,000 mL, use of uterotonics (excluding prophylactic oxytocin) or Bakri balloon, surgical management of hemorrhage, blood transfusion, hysterectomy, thromboembolism, admission to intensive care unit, or maternal death. Multivariable Poisson regression models with robust error variance were used to estimate adjusted relative risks (aRRs) with 95% confidence intervals (CIs).

RESULTS

 Of 8,623 deliveries in the study period, 2,691 (31.2%) had CDs at term, with 1,709 (67.3%) scheduled CDs, and 983 (36.5%) unscheduled CDs. Overall, the rate of CMHO was 23.3%, and the rate of blood transfusion was 4.1%. CMHOs were two-fold higher among unscheduled (34.5%) than scheduled CDs (16.9%; aRR = 2.18; 95% CI: 1.81-2.63). The aRRs for blood transfusion and surgical interventions to manage postpartum hemorrhage were three times higher with unscheduled than scheduled CDs. The subgroup analysis indicated that among the cohorts without prior uterine surgery, the rate of the CMHOs was significantly higher when the CD was unscheduled versus scheduled (aRR 1.85; 95% CI 1.45-2.37).

CONCLUSION

 Compared to scheduled CDs, the composite hemorrhagic adverse outcomes were significantly higher with unscheduled CDs.

KEY POINTS

· Unscheduled cesareans are at higher risk of hemorrhage.. · Unscheduled cesareans are at higher risk of transfusion.. · Atony treatment is higher in unscheduled cesareans..

Association Between Laboratory Coagulation Parameters and Postpartum Hemorrhage in Preterm and Term Caesarean Section: A Retrospective Analysis

Background: Deranged antepartum laboratory parameters may be risk factors for postpartum hemorrhage (PPH). However, whether this is also valid in women who give birth prematurely is currently unknown. Methods: We performed a retrospective single-center study to assess the role of antepartum hemoglobin, platelet count, fibrinogen, activated partial thromboplastin time, and prothrombin time as risk factors for PPH following caesarean section. We defined PPH as documented blood loss of at least 1 L and/or transfusion of red blood cell concentrates. We stratified the included patients according to gestational age: extremely preterm (gestational age < 28 weeks), very preterm (gestational age between 28 and 32 weeks), late and moderate preterm (gestational age between 32 and 37 weeks), and term (gestational age ≥ 37 weeks). Results: We included 1734 patients, 112 (6%) of whom had PPH. In total, 19 patients (10%) were in the extremely preterm group, 13 patients (10%) were in the very preterm group, 44 patients (9%) were in the late and moderate preterm group, and 36 patients (4%) were in the term group. Hemoglobin predicted PPH in all gestational age groups. Platelet count was associated with PPH in term, but not in preterm patients. Fibrinogen was associated with PPH in late prematurity but not in term patients and not in patients with early or extreme prematurity. Conclusions: Antepartum hemoglobin was the only factor predicting PPH in preterm and term caesarean sections. Platelet count and fibrinogen concentration were associated with PPH in term and late prematurity, respectively, but not in earlier stages of prematurity.

Oxytocin with calcium vs oxytocin for induction of labor in women with term premature rupture of membranes: a randomized controlled trial

BACKGROUND

Intravenous calcium administration has shown promise in enhancing uterine contractions and reducing blood loss during cesarean delivery, but this regimen has not been compared in vaginal labor induction.

OBJECTIVE

This study aimed to determine the efficacy of oxytocin combined with calcium vs oxytocin alone for inducing labor in women with term premature rupture of membranes.

STUDY DESIGN

This single-blind, randomized controlled trial was conducted between October 2022 and May 2023 at a tertiary university hospital. Patients diagnosed with premature rupture of membranes were randomly allocated into 2 groups. The intervention group received a bolus of 10 mL of calcium gluconate followed by a continuous infusion of oxytocin via a pump (n=210), whereas the control group received only oxytocin infusion (n=218). The primary outcome was successful vaginal deliveries within 24 hours after labor induction. The secondary outcomes included the interval from labor induction to delivery, vaginal delivery blood loss, and maternal and neonatal complications.

RESULTS

Baseline characteristics, including maternal age, body mass index, and Bishop score before labor induction, were comparable between the groups. The rate of vaginal delivery within 24 hours after labor induction was statistically higher in the intervention group (79.52% vs 70.64%; P=.04). The participants in the intervention group experienced a shortened interval between labor induction and delivery (10.48 vs 11.25 hours; P=.037) and demonstrated a higher success rate in labor induction assessed by the onset of the active phase (93.80% vs 87.61%; P=.04) without increasing the cesarean delivery rate. Reduced hemorrhage was observed in the intervention group (242.5 vs 255.0 mL; P=.0015), and the maternal and neonatal outcomes were comparable between the groups.

CONCLUSION

The coadministration of calcium and oxytocin in labor induction among pregnancies with premature rupture of membranes was more efficient and safer than the administration of oxytocin alone. Our research suggests that the combination therapy of calcium and oxytocin may offer significant advantages during the process of labor induction and result in better outcomes. VIDEO ABSTRACT.

Intravenous Calcium to Decrease Blood Loss During Intrapartum Cesarean Delivery: A Randomized Controlled Trial

OBJECTIVE

To evaluate whether prophylactic administration of 1 g of intravenous calcium chloride after cord clamping reduces blood loss from uterine atony during intrapartum cesarean delivery.

METHODS

This single-center, block-randomized, placebo-controlled, double-blind superiority trial compared the effects of 1 g intravenous calcium chloride with those of saline placebo control on blood loss at cesarean delivery. Parturients at 34 or more weeks of gestation requiring intrapartum cesarean delivery after oxytocin exposure in labor were enrolled. Calcium or saline placebo was infused over 10 minutes beginning 1 minute after umbilical cord clamping in addition to standard care with oxytocin. The primary outcome was quantitative blood loss, analyzed by inverse Gaussian regression. Planned subgroup analysis excluded nonatonic bleeding, such as hysterotomy extension, arterial bleeding, and occult placenta accreta. We planned to enroll 120 patients to show a 200-mL reduction in quantitative blood loss in planned subgroup analysis, assuming up to 40% incidence of nonatonic bleeding (80% power, α<0.05).

RESULTS

From April 2022 through March 2023, 828 laboring parturients provided consent and 120 participants were enrolled. Median blood loss was 840 mL in patients allocated to calcium chloride (n=60) and 1,051 mL in patients allocated to placebo (n=60), which was not statistically different (mean reduction 211 mL, 95% CI -33 to 410). In the planned subgroup analysis (n=39 calcium and n=40 placebo), excluding cases of surgeon-documented nonatonic bleeding, calcium reduced quantitative blood loss by 356 mL (95% CI 159-515). Rates of reported side effects were similar between the two groups (38% calcium vs 42% placebo).

CONCLUSION

Prophylactic intravenous calcium chloride administered during intrapartum cesarean delivery after umbilical cord clamping did not significantly reduce blood loss in the primary analysis. However, in the planned subgroup analysis, calcium infusion significantly reduced blood loss by approximately 350 mL. These data suggest that this inexpensive and shelf-stable medication warrants future study as a novel treatment strategy to decrease postpartum hemorrhage, the leading global cause of maternal morbidity and mortality.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT05027048.

Admission Hypocalcemia and the Need for Endoscopic and Clinical Interventions among Patients with Upper Gastrointestinal Bleeding

INTRODUCTION

Calcium is an essential co-factor in the coagulation cascade, and hypocalcemia is associated with adverse outcomes in bleeding patients, including trauma patients, women with postpartum hemorrhage, and patients with intracranial hemorrhage. In this retrospective, single-center, cohort study, we aimed to determine whether admission-ionized calcium (Ca++) is associated with higher rates of therapeutic interventions among patients presenting with acute nonvariceal upper gastrointestinal bleeding (NV-UGIB).

METHODS

Adult patients admitted due to NV-UGIB between January 2009 and April 2020 were identified. The primary outcome was defined as a need for clinical intervention (two or more packed cell transfusions, need for endoscopic, surgical, or angiographic intervention). Univariate and multivariable logistic regression analyses were performed to determine whether Ca++ was an independent predictor of the need for therapeutic interventions. Propensity score matching was performed to adjust the imbalances of covariates between the groups.

RESULTS

A total of 434 patients were included, of whom 148 (34.1%) had hypocalcemia (Ca++ <1.15 mmol/L). Patients with hypocalcemia were more likely to require therapeutic interventions than those without hypocalcemia (48.0% vs. 18.5%, p < 0.001). Specifically, patients with hypocalcemia were more likely to require endoscopic intervention for control of bleeding (25.0% vs. 15.7%, p = 0.03) and multiple packed cell transfusions (6.8% vs. 0.3%, p < 0.001). Additionally, they had significantly longer hospital stay (5.0 days [IQR 3.0-8.0] vs. 4.0 days [IQR 3.0-6.0], p = 0.01). After adjusting for multiple covariates, Ca++ was an independent predictor of the need for therapeutic intervention (aOR 1.62, 95% confidence interval [CI] 1.22-2.14, p < 0.001). The addition of Ca++ to the Modified Glasgow Blatchford score improved its accuracy in the prediction of therapeutic intervention from AUC of 0.68 (95% CI 0.63-0.72) to 0.72 (95% CI 0.67-0.76), p = 0.02. After incorporation of the propensity score, the results did not change significantly.

CONCLUSION

These findings suggest that hypocalcemia is common and is associated with an adverse clinical course in patients with NV-UGIB. Measurement of Ca++ on admission may facilitate risk stratification in these patients. Trials are needed to assess whether the correction of hypocalcemia will lead to improved outcomes.

Coagulation management and transfusion in massive postpartum hemorrhage

PURPOSE OF REVIEW

Excessive bleeding during and following childbirth remains one of the leading causes of maternal mortality.

RECENT FINDINGS

Current guidelines differ in definitions and recommendations on managing transfusion and hemostasis in massive postpartum hemorrhage (PPH). Insights gained from trauma-induced coagulopathy are not directly transferable to the obstetric population due to gestational alterations and a differing pathophysiology.

SUMMARY

Factor deficiency is uncommon at the beginning of most etiologies of PPH but will eventually develop from consumption and depletion in the absence of bleeding control. The sensitivity of point-of-care tests for fibrinolysis is too low and may delay treatment, therefore tranexamic acid should be started early at diagnosis even without signs for hyperfibrinolysis. Transfusion management may be initiated empirically, but is best to be guided by laboratory and viscoelastic assay results as soon as possible. Hypofibrinogenemia is well detected by point-of-care tests, thus substitution may be tailored to individual needs, while reliable thresholds for fresh frozen plasma (FFP) and specific components are yet to be defined. In case of factor deficiency, prothrombin complex concentrate or lyophilized plasma allow for a more rapid restoration of coagulation than FFP. If bleeding and hemostasis are under control, a timely anticoagulation may be necessary.

Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022

BACKGROUND

Management of peri-operative bleeding is complex and involves multiple assessment tools and strategies to ensure optimal patient care with the goal of reducing morbidity and mortality. These updated guidelines from the European Society of Anaesthesiology and Intensive Care (ESAIC) aim to provide an evidence-based set of recommendations for healthcare professionals to help ensure improved clinical management.

DESIGN

A systematic literature search from 2015 to 2021 of several electronic databases was performed without language restrictions. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used to assess the methodological quality of the included studies and to formulate recommendations. A Delphi methodology was used to prepare a clinical practice guideline.

RESULTS

These searches identified 137 999 articles. All articles were assessed, and the existing 2017 guidelines were revised to incorporate new evidence. Sixteen recommendations derived from the systematic literature search, and four clinical guidances retained from previous ESAIC guidelines were formulated. Using the Delphi process on 253 sentences of guidance, strong consensus (>90% agreement) was achieved in 97% and consensus (75 to 90% agreement) in 3%.

DISCUSSION

Peri-operative bleeding management encompasses the patient's journey from the pre-operative state through the postoperative period. Along this journey, many features of the patient's pre-operative coagulation status, underlying comorbidities, general health and the procedures that they are undergoing need to be taken into account. Due to the many important aspects in peri-operative nontrauma bleeding management, guidance as to how best approach and treat each individual patient are key. Understanding which therapeutic approaches are most valuable at each timepoint can only enhance patient care, ensuring the best outcomes by reducing blood loss and, therefore, overall morbidity and mortality.

CONCLUSION

All healthcare professionals involved in the management of patients at risk for surgical bleeding should be aware of the current therapeutic options and approaches that are available to them. These guidelines aim to provide specific guidance for bleeding management in a variety of clinical situations.

Guideline No. 431: Postpartum Hemorrhage and Hemorrhagic Shock

OBJECTIVE

This guideline aims to provide evidence for prevention, recognition, and treatment of postpartum hemorrhage including severe hemorrhage leading to hemorrhagic shock.

TARGET POPULATION

All pregnant patients.

BENEFITS, HARMS, AND COSTS

Appropriate recognition and treatment of postpartum hemorrhage can prevent serious morbidity while reducing costs to the health care system by minimizing more costly interventions and length of hospital stays.

EVIDENCE

Medical literature, PubMed, ClinicalTrials.gov, the Cochrane Database, and grey literature were searched for articles, published between 2012 and 2021, on postpartum hemorrhage, uterotonics, obstetrical hemorrhage, and massive hemorrhage protocols.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

All members of the health care team who care for labouring or postpartum women, including, but not restricted to, nurses, midwives, family physicians, obstetricians, and anesthesiologists.

RECOMMENDATIONS

Epidemiology and definition of PPH worldwide

Postpartum/peripartum hemorrhage (PPH) is an obstetric emergency complicating 1-10% of all deliveries and is a leading cause of maternal mortality and morbidity worldwide. However, the incidence of PPH differs widely according to the definition and criteria used, the way of measuring postpartum blood loss, and the population being studied with the highest numbers in developing countries. Despite all the significant progress in healthcare, the incidence of PPH is rising due to an incomplete implementation of guidelines, resulting in treatment delays and suboptimal care. A consensus clinical definition of PPH is needed to enable awareness, early recognition, and initiation of appropriate intensive treatment. Unfortunately, the most used definition of PPH based on blood loss ≥500 ml after delivery suffers from inaccuracies in blood loss quantification and is not clinically relevant in most cases, as the amount of blood loss does not fully reflect the severity of bleeding.

Calcium chloride for the prevention of uterine atony during cesarean delivery: A pilot randomized controlled trial and pharmacokinetic study

STUDY OBJECTIVE

To assess the feasibility, patient tolerance, pharmacokinetics, and potential effectiveness of a randomized controlled trial protocol investigating intravenous calcium chloride for the prevention of uterine atony during cesarean delivery.

DESIGN

Double-blind, randomized controlled pilot trial with nested population pharmacokinetic analysis.

SETTING

This study was performed at Lucile Packard Children's Hospital, from August 2018 to September 2019.

PATIENTS

Forty patients with at least two risk factors for uterine atony at the time of cesarean delivery.

INTERVENTIONS

One gram of intravenous calcium chloride (n = 20 patients) or a saline placebo control (n = 20 patients), in addition to standard care with oxytocin, upon umbilical cord clamping.

MEASUREMENTS

The primary efficacy-related outcome was the presence of uterine atony defined as the use of a second-line uterotonic medication, surgical interventions for atony, or hemorrhage with blood loss >1000 mL. Blood loss, uterine tone numerical rating scores, serial venous blood calcium levels, hemodynamics, and potential side effects were also assessed.

MAIN RESULTS

The study protocol proved feasible. The incidence of atony was 20% in parturients who received calcium compared to 50% in the placebo group (relative risk 0.38, P = 0.07, 95% CI 0.15-1.07, NNT 3.3). Calcium recipients tolerated the drug infusion well, with no adverse events and an equal incidence of potential side effects in the calcium and placebo groups. Ionized calcium concentration rose significantly in all patients who received calcium infusion, from baseline 1.18 mmol/L to peak levels 1.50-1.60 mmol/L. One-compartment population pharmacokinetics established clearance of 0.93 (95% CI 0.63-1.52) L/min and volume of distribution 76 (95% CI 49-94) L.

CONCLUSIONS

In this pilot study, investigators found that intravenous calcium chloride was well-tolerated by the 20 patients assigned to receive the study drug and may be effective in prevention of uterine atony. A 1-g dose was sufficient to substantially increase calcium levels without any critically elevated lab values or concern for adverse side effects. These encouraging findings warrant further investigation of calcium as a novel agent to prevent uterine atony with an adequately powered clinical trial. Clinical trial registry NCT03867383 https://clinicaltrials.gov/ct2/show/NCT03867383.

Low serum calcium is associated with perioperative blood loss and transfusion rate in elderly patients with hip fracture: a retrospective study

Background

To investigate whether hypocalcemia influenced total blood loss and transfusion rate in elderly patients with hip fracture.

Methods

From our hip fracture database, patients were consecutively included between January 2014 and December 2020. Serum calcium level was corrected for albumin concentration, and hypocalcaemia was defined as corrected calcium < 2.11 mmol/L. Hemoglobin and hematocrit were obtained on admission day and postoperative day, and blood transfusions were collected. According to the combination formulas of Nadler and Gross, the total blood loss of each patient was calculated. Risk factors were further analyzed by multivariate linear regression.

Results

A total of 583 consecutive elderly hip fracture patients were finally included (mean age 79.32 ± 8.18 years, 68.61% female). On admission, the mean serum corrected calcium level was 2.17 ± 0.14 mmol/L, and the prevalence of hypocalcemia was 33.11% (95% CI: 29.42–37.02). When comparing patients with normal calcium, hypocalcemia patients exhibited a higher blood transfusion rate (7.69% vs 16.06%, P < 0.05), and significantly larger total blood loss (607.86 ± 497.07 ml vs 719.18 ± 569.98 ml, P < 0.05). Multivariate linear regression analysis showed that male, anemia on admission, time from injury to hospital, intertrochanteric fracture, blood transfusion and hypocalcemia were independently associated with increased total blood loss (P < 0.05).

Conclusion

Hypocalcemia is common in elderly patients with hip fracture, and significantly associated with more total blood loss and blood transfusion. The other risk factors for increased total blood loss are male, anemia on admission, time from injury to hospital, intertrochanteric fracture, and blood transfusion.

Level of evidence

Level III, retrospective study.

Hypocalcemia is associated with adverse clinical course in patients with upper gastrointestinal bleeding

Acute non-variceal upper gastrointestinal bleeding (NV-UGIB) is associated with significant morbidity and mortality. Early and efficient risk stratification can facilitate management and improve outcomes. We aimed to determine whether the level of ionized calcium (Ca⁺⁺), an essential co-factor in the coagulation cascade, is associated with the severity of bleeding and the need for advanced interventions among these patients. This was a retrospective single-center cohort study of all patients admitted due to NV-UGIB. The primary outcome was transfusion of ≥ 2 packed red blood cells, arterial embolization, or emergency surgery. Secondary outcomes included (1) transfusion of ≥ 2 packed red blood cells, (2) arterial embolization, or emergency surgery, and (3) all-cause in-hospital mortality. Multivariable logistic regression was performed to determine whether Ca⁺⁺ was an independent predictor of these adverse outcomes. 1345 patients were included. Hypocalcemia was recorded in 604 (44.9%) patients. The rates of primary adverse outcome were significantly higher in the hypocalcemic group, 14.4% vs. 5.1%, p < 0.001. Secondary outcomes-multiple transfusions, need for angiography or surgery, and mortality were also increased (9.9% vs. 2.3%, p < 0.001, 5.3% vs. 2.8%, p = 0.03, and 33.3% vs. 24.7%, p < 0.001, respectively). Hypocalcemia was an independent predictor of primary and all the secondary outcomes, except mortality. Hypocalcemia in high-risk hospitalized patients with NV-UGIB is common and independently associated with adverse outcomes. Ca⁺⁺ monitoring in this population may facilitate the rapid identification of high-risk patients. Trials are needed to assess whether correction of hypocalcemia will lead to improved outcomes.

Association between admission serum calcium and hemoglobin in older patients with hip fracture: a cross-sectional study

PURPOSE

Serum calcium ion is an essential cofactor in the coagulation cascade, and low calcium concentration is associated with more bleeding in many diseases. This study aimed to describe the prevalence of hypocalcaemia, and investigate the correlation between calcium and hemoglobin (Hb) level in older patients with hip fracture.

METHODS

From our established hip fracture database, patients were consecutively included between January 2014 and December 2020. Serum calcium concentration was corrected for albumin level, and hypocalcaemia was defined as corrected calcium below the lower limit of reference range (< 2.11 mmol/L), and further sub-grouped into mild hypocalcaemia (1.90-2.11 mmol/L) and severe hypocalcaemia (< 1.90 mmol/L). Pearson correlation, scatter plots and partial correlation analyses were performed to evaluate the associations between various factors and Hb level.

RESULTS

A total of 1032 older patients with hip fracture were finally included (mean age 79.2 years, 66.0% female). At admission, the mean serum corrected calcium and Hb levels were 2.14 mmol/L and 11.0 g/dL. Overall, the prevalence of hypocalcaemia and anemia were 39.5% and 71.6%, respectively. After adjusting for all variables, low serum calcium concentration was positively associated with low Hb level in the total study (partial correlation r = 0.13, P < 0.001), as well as in patients with femur neck fracture (partial correlation r = 0.16, P = 0.001) and intertrochanteric fracture (partial correlation r = 0.13, P = 0.003).

CONCLUSION

Hypocalcaemia was common in older patients with hip fracture, and independently and positively associated with low Hb level. Further study on causal relationship between calcium and Hb level in older patients with hip fracture is necessary.

Placenta accreta spectrum disorder: updates on anesthetic and surgical management strategies

Placenta accreta spectrum (PAS) is a leading contributor to major obstetric hemorrhage and severe maternal morbidity in the developed world. In the United States, PAS has become the most common cause of peripartum hysterectomy. Over the last 40 years, clinicians have also witnessed a dramatic increase in the incidence of PAS. In the 1950s, the incidence of PAS was reported to be 0.03 per 1000 pregnancies. Recent epidemiological studies estimate that the PAS incidence is between 0.79 and 3.11 in 1000 pregnancies. As a consequence, obstetric anesthesiologists are increasingly likely to be called upon to manage women with suspected PAS for delivery. Given the increasing incidence and the morbidity burden associated with PAS, anesthesiologists play a vital role in optimizing maternal outcomes for women with PAS. This review will provide up-to-date information on nomenclature, pathophysiology, risk factors, antenatal detection, systemic preparations (includes timing of delivery, location of surgery, pre-operative evaluation and patient positioning), surgical and anesthetic approach, intra-operative management, invasive radiology and postoperative plans.