The aim of this paper is not to outline a specific medical-surgical algorithm for managing PPH, but rather to give an overview for system-wide preparedness that should be considered in planning to mitigate this frequent, potentially life-threatening, obstetrical emergency.
Introduction
Postpartum hemorrhage (PPH) is estimated to occur in 3% of US deliveries1 and is probably the most common life-threatening emergency encountered by obstetricians. In contrast to other serious obstetric conditions encountered less frequently (e.g., hypertensive crisis, sepsis, cardiac disease, pulmonary embolism, amniotic fluid embolism), PPH will likely be managed by obstetricians on a regular, perhaps weekly or monthly basis. The aim of this paper is not to outline a specific medical-surgical algorithm for managing PPH, but rather to give an overview of system-wide preparedness that should be considered in planning to mitigate this frequent, potentially life-threatening, obstetrical emergency.
Defining PPH
There are a multitude of definitions for PPH in the medical literature. When interpreting published reports on PPH, it is important to recognize these differences and keep in mind that population-based studies often rely upon ICD codes, which themselves do not incorporate a quantitative definition. Recently the American College of Obstetricians and Gynecologists’ (ACOG) reVITALize program, 2 which aims to standardize clinical terms, defined PPH as a cumulative blood loss ≥ 1,000 mL, or blood loss accompanied by signs and symptoms of hypovolemia, within 24 hours after the birth process. This definition is also used in the recently updated 2017 ACOG “Postpartum Hemorrhage” Practice Bulletin #183.3 Going forward, the development of “core outcome sets” to define critical clinical parameters in research should serve to accelerate discovery and improvements in PPH management.4
Scope of the problem
Obstetric hemorrhage is the leading cause of global maternal mortality.5 In a chart review of 95 maternal deaths among 1.5 million deliveries from 2000 to 2006, Clark and colleagues found PPH to be the third leading cause of maternal death, behind complications of preeclampsia and amniotic fluid embolism.6 Multiple studies from various developed countries including the United States have reported increasing trends in PPH over the last several decades.1 In this country, all-cause maternal mortality is increasing,7 bringing with it an increase in PPH-related maternal mortality and severe morbidity, much of which is preventable.
PPH-related mortality and Its root causes
It is evident from published studies that the majority of PPH-related maternal deaths are preventable with standard obstetrical care. A report from North Carolina (1995-1999) estimated that PPH deaths were avoidable in 93% of cases,8 and a study from a large US hospital system (2000-2006) estimated that 73% of PPH deaths were avoidable with standard care.6 Such findings have been confirmed in studies published from other industrialized countries. Of the commonest causes of contemporary maternal mortality, PPH is probably the most preventable. In Clark and Hankins’ commentary, “Preventing maternal death: 10 clinical diamonds,” 6 clinical diamonds are directed specifically to PPH mortality.9
Common root causes of preventable PPH-related maternal mortality are outlined in Table 1. Typically, some or all of the response cascade to significant bleeding is delayed to the point where irreversible cardiovascular collapse and coagulopathy occur. These steps in managing PPH may not always occur in a serial fashion, sometimes requiring simultaneous or parallel deployment in accelerated severe cases. The problem typically begins with failure to identify significant bleeding (quantifying blood loss), changes in vital signs (hypotension, tachycardia, oliguria), calling for help (second physician, anesthesiologist), preparation of blood products (type & crossmatch), administration of appropriate blood products (massive transfusion protocol), and assessment of essential laboratory parameters (hemoglobin, prothrombin time/partial prothrombin time, fibrinogen, potassium, calcium) during resuscitation. An omission or delay at any of these steps may result in unsuccessful resolution of this common obstetrical emergency. With massive fluid and blood component replacement, careful monitoring for not just anemia and coagulopathy, but also potentially lethal cardiac pro-arrhythmic electrolyte imbalances (i.e., hyperkalemia and hypocalcemia) are critical; the use of established protocols may serve to prompt appropriately-timed assessments.
Often these failures are the result of system deficiencies in the design and model of care in that hospital. The patient is dependent upon her clinical providers, who are dependent upon hospital services, all of which are dependent upon the system’s safety culture. The efficient and successful performance of the providers within the system clinical environment is greatly impacted by the culture of quality and safety set forth by administration, physician and nursing leadership. Systems with a “just culture” environment encourage transparency and benefit by learning from system deficiencies and provider errors.10,11 Quality and safety initiatives are dependent upon strong leadership, time-consuming, costly, and require ongoing maintenance and refinement. There is a wide range of evolution in adopting these initiatives across obstetrical units nationwide; some facilities are far further down the path than others. It is believed that investment in quality and safety initiatives will ultimately reduce avoidable harm (thus reduce liability), reduce costs (thus increase value of care and revenue), and ultimately benefit all involved in the provision of medical care, from patient, to providers, to payers and society. Data indicate such an effect when systems are adequately prepared.12,13 Development and adoption of clinical service guidelines (e.g., quantifying blood loss, massive transfusion protocol) and prospective monitoring of events (i.e., event debriefings, quality metric dashboard) will serve to refine processes and prevent future delays in provision of complex, life-saving care.
Designated levels of maternity care
Across the United States there are > 3,000 hospitals that provide maternity services for approximately 4 million births per annum. Clinical capabilities range widely, from small community hospitals without 24/7 anesthesiology and blood banking services, to specialized quaternary-care “Percreta Centers” which manage deliveries at the highest risk for exsanguination and maternal death. Every center providing obstetrical care, however, should be prepared to recognize PPH, initiate basic treatment of the underlying cause, and have a plan in place to transfer patients, if indicated, to a facility with the appropriate level of care. While many patients who develop PPH do not have identifiable pre-labor risk factors, some will be readily identified as high-risk (e.g., placenta previa with prior cesarean) and should be referred for transfer of care well prior to anticipated delivery. Development of designated levels of maternity care will serve to reduce preventable severe maternal morbidity and mortality, by timely referral to an appropriately equipped center for management of at-risk and complex cases.14
Guidelines, protocols, policies and material
National medical organization guidelines have evolved from simple recommendations for treatment of a given condition to a more integrated systems approach to prevention, management, and ongoing improvement. With regard to PPH, development of institutional guidelines, protocols and policies should address such issues as general PPH management, massive blood transfusion, and patient transport to a higher level of care. Protocols for specific emergencies such as amniotic fluid embolism (AFE) have also been advocated.15 Some specific considerations for PPH preparation include:
Systematic Estimation of Blood Loss
It is perplexing that historically, many inpatient hospital intake/output (I/O) flow sheets have captured oral intake, intravenous intake, urine output, and emesis, but not quantitative blood loss, especially in the obstetric setting where blood loss is the norm and excessive blood loss is not uncommon. Obstetric blood loss is often underestimated16 and simple education can improve blood loss estimates.17 Efforts to quantify blood loss, whether by active subjective assessment or gravimetric methods, are increasingly being adopted by obstetric units, some incorporating assessments into the electronic medical record on a per hour and/or per shift basis.
Maternal Early Warning System
In 2012 the UK National Health System adopted the Modified Early Obstetric Warning System (MEOWS) into its maternal safety standards.18 A prospective validation of MEOWS found that 30% of patients triggered evaluation and 13% experienced a complication, predicting maternal morbidity with 89% sensitivity and 79% specificity.19 In the United States, the National Partnership for Maternal Safety proposed Maternal Early Warning Criteria,20 thresholds including heart rate (HR) < 50 or > 120 beats/minute, systolic blood pressure (SBP) < 90 or > 160 mmHg, diastolic blood pressure > 100 mmHg, respiratory rate < 10 or > 30 breaths/minute, oxygen saturation < 95%, and urine output < 35 mL/hour for ≥ 2 hours. Other parameters, such as the shock index (SI), calculated as HR/SBP, and delta-SI (i.e. current SI minus baseline SI), are promising physiologic parameters for such systems of maternal surveillance and deserve further research.21
Hemorrhage Cart
Obstetric hemorrhage carts are useful in prompt mobilization of equipment
necessary to treat PPH, including transfusion lines, surgical instruments, sutures, tamponade balloons and other material such as consent forms, algorithms, and checklists.12 Given the logistics of requesting equipment in emergency conditions, a well-equipped and maintained obstetric hemorrhage cart can serve to avoid treatment delays per evidence-based guidelines. Such preparation can be carried further, with specialty percreta centers stocking operating rooms with “percreta carts” containing a more elaborate array of instrumentation for these complicated cases.22
Uterine Balloon Tamponade
Use of a uterine-specific balloon catheter to control PPH was first described in 1951 by Holtz.23 Over the past 2 decades, uterine tamponade by various balloon devices (some US Food and Drug Administration-approved for specific use) has gained popularity due to ease of use and high success rates.24,25 Current ACOG guidelines support uterine balloon tamponade (UBT) in management of PPH (ACOG Practice Bulletin #183), stating “…it is important for institutions to adopt an approach and train personnel in this approach.” A population-based retrospective cohort study of 72,529 women found that incidence of invasive procedures (i.e., pelvic vessel ligation, arterial embolization, hysterectomy) following vaginal delivery was significantly lower in institutions that routinely used UBT compared to those that did not.26
Uterine Compression Suture
Since the original report by B-Lynch in 1997,27 a variety of uterine compression suture procedures have been described for control of PPH at laparotomy. The reported success rates of these procedures to control PPH are generally well over 75%28 and the procedures are technically quick and simple. The only disadvantage is that laparotomy is required, which is of course not an issue at the time of cesarean. This author finds the B-Lynch procedure easiest to perform, and preferable to other techniques that may directly oppose the anterior and posterior uterine walls in such a way that uterine synechiae may become a concern.
Thromboelastography
Point-of-care testing for hemostatic function can be performed by thromboelastography (TEG) and an adaptation called rotational thromboelastometry (ROTEM). Both TEG and ROTEM, as a single test, provide information regarding clot initiation, strength, and lysis, allowing for a more tailored transfusion response. Some obstetrical units have incorporated TEG/ROTEM into their massive transfusion protocols.29
Tranexamic Acid (TXA)
The landmark 2017 WOMAN trial was a multinational, randomized, double-blind, placebo-controlled trial of women with a clinical diagnosis of PPH after vaginal birth or caesarean section.30 From 2010 to 2016, a total of 20,060 women were assigned to receive either 1 g IV TXA or matching placebo, in addition to usual PPH care. Death due to bleeding was significantly reduced in women given TXA, especially if given within 3 hours of birth. Thromboembolic events did not differ significantly between groups. TXA appears to be beneficial in treating PPH and should be integrated into hospital PPH guidelines; the role of prophylactic TXA deserves further study.31
Preparation and teamwork
Management of PPH is a team effort. Depending upon complexity, other disciplines such as Gynecologic Oncology, Urology, Hematology and Critical Care specialists are required. Efficient teamwork requires planning and ongoing practice, much like any complex group effort such as seen in athletic team events, aviation, musical concerts or military operations.
Education
Multiple
of online material devoted to management of PPH are available for individual or group education. The “Obstetric Hemorrhage Bundle” prepared by the Council on Patient Safety in Women’s Health Care comprehensively addresses PPH readiness, recognition, prevention, response, reporting, and systems learning. This material is an invaluable resource to reduce patient risk and improve outcomes; bundles are also available for other high-risk clinical conditions. The Advanced Practice Strategies (APS) GNOSIS for Obstetrics, available by subscription, provides assessment of learner baseline knowledge and judgement, and tailors individualized learning paths in areas requiring supplemental education.
Simulation
Simulation in healthcare has dramatically evolved in recent years, but is not a novel idea, as illustrated by Babcock’s 1924 publication advocating drills for managing intraoperative cardiopulmonary collapse.32 A joint publication in 2011 from ACOG, the Society for Maternal-Fetal Medicine (SMFM) and other organizations advocates integration of simulation as part of a comprehensive strategy to improve obstetrical outcomes.33 Evidence that the practice of simulation in the obstetric arena improves maternal-fetal outcomes continues to accrue.34
Debriefings and Review
Maternal mortality is just the “tip of the iceberg” and is a rare occurrence at any obstetric unit in industrialized countries. Severe maternal morbidity (i.e., 4 or more units of red blood cells, intensive care unit admission) is significantly more common and provides an opportunity for retrospective review in order to improve clinical processes, structure and outcomes.35 A consensus statement from ACOG, SMFM, AWHONN and the Joint Commission recommends that all cases of severe maternal morbidity, whether sentinel events or not, undergo a thorough and credible multidisciplinary comprehensive review.36 Structured team debriefings are an excellent starting point for the review process.
Quality metrics
Tracking of process and outcome metrics is a fundamental component of a hospital’s quality program. Using a modified Delphi procedure, Woiski and colleagues developed a set of guideline-based quality indictors to measure guideline adherence in PPH care. From 69 extracted recommendations, 50 were selected and translated into 22 quality indicators on professional performance and organization of PPH care. Such PPH-related metrics should be considered for integration into a hospital’s or system’s quality and patient safety metric dashboard.
Conclusion
The majority of PPH-related maternal deaths and many severe maternal morbidities are avoidable with provision of timely interventions. From the glass-half-full perspective, significant outcome improvements can be readily accomplished with individual and institutional preparations for this common obstetrical emergency.
Disclosure Dr. Dildy is co-inventor of the Belfort-Dildy Obstetrical Tamponade System, assigned to B&D Medical Development LLC (Park City, UT) of which he is a manager. The system is manufactured and marketed by Clinical Innovations, LLC (Murray, UT) as the ebbTM Complete Tamponade System for use in treating postpartum hemorrhage.
REFERENCES
1. WM, Kuklina EV, Berg CJ. Trends in postpartum hemorrhage: United States, 1994-2006. Am J Obstet Gynecol. 2010;202:353 e1-6.
2. Menard MK, Main EK, Currigan SM. Executive summary of the reVITALize initiative: standardizing obstetric data definitions. Obstet Gynecol. 2014;124:150-3.
3. Committee on Practice Bulletins--Obstetrics. Practice Bulletin #183: Postpartum Hemorrhage. Obstet Gynecol. 2017 Oct;130(4):e168-e186.
4. Dildy GA. A call to action for data definition standardisation and core outcome sets. BJOG. 2017;124:1840.
5. Kassebaum NJ, Bertozzi-Villa A, Coggeshall MS, et al. Global, regional, and national levels and causes of maternal mortality during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2014;384:980-1004.
6. Clark SL, Belfort MA, Dildy GA, Herbst MA, Meyers JA, Hankins GD. Maternal death in the 21st century: causes, prevention, and relationship to cesarean delivery. Am J Obstet Gynecol. 2008;199:36 e1-5; discussion 91-2 e7-11.
7. Moaddab A, Dildy GA, Brown HL, et al. Health Care Disparity and State-Specific Pregnancy-Related Mortality in the United States, 2005-2014. Obstet Gynecol. 2016;128:869-75.
8. Berg CJ, Harper MA, Atkinson SM, et al. Preventability of pregnancy-related deaths: results of a state-wide review. Obstet Gynecol. 2005;106:1228-34.
9. Clark SL, Hankins GD. Preventing maternal death: 10 clinical diamonds. Obstet Gynecol. 2012;119:360-4.
10. Marx D. How building a ‘just culture’ helps an organization learn from errors. OR Manager. 2003;19:1, 14-5, 20.
11. Frankel AS, Leonard MW, Denham CR. Fair and just culture, team behavior, and leadership engagement: The tools to achieve high reliability. Health Serv Res. 2006;41:1690-709.
12. Shields LE, Smalarz K, Reffigee L, Mugg S, Burdumy TJ, Propst M. Comprehensive maternal hemorrhage protocols improve patient safety and reduce utilization of blood products. Am J Obstet Gynecol. 2011;205:368 e1-8.
13. Shields LE, Wiesner S, Fulton J, Pelletreau B. Comprehensive maternal hemorrhage protocols reduce the use of blood products and improve patient safety. Am J Obstet Gynecol. 2015;212:272-80.
14. Hankins GD, Clark SL, Pacheco LD, O’Keeffe D, D’Alton M, Saade GR. Maternal mortality, near misses, and severe morbidity: lowering rates through designated levels of maternity care. Obstet Gynecol. 2012;120:929-34.
15. Barbieri RL, Farber MK. Does your obstetric unit have a protocol for treating amniotic fluid embolism? OBG Management 2014;26:8-14.
16. Stafford I, Dildy GA, Clark SL, Belfort MA. Visually estimated and calculated blood loss in vaginal and cesarean delivery. Am J Obstet Gynecol. 2008;199:519 e1-7.
17. Dildy GA, 3rd, Paine AR, George NC, Velasco C. Estimating blood loss: can teaching significantly improve visual estimation? Obstet Gynecol. 2004;104:601-6.
18. Mackintosh N, Watson K, Rance S, Sandall J. Value of a modified early obstetric warning system (MEOWS) in managing maternal complications in the peripartum period: an ethnographic study. BMJ Qual Saf. 2014;23:26-34.
19. Singh S, McGlennan A, England A, Simons R. A validation study of the CEMACH recommended modified early obstetric warning system (MEOWS). Anaesthesia. 2012;67:12-8.
20. Mhyre JM, D’Oria R, Hameed AB, et al. The maternal early warning criteria: a proposal from the national partnership for maternal safety. Obstet Gynecol. 2014;124:782-6.
21. Kohn JR, Dildy GA, Eppes CS. Shock index and delta-shock index are superior to existing maternal early warning criteria to identify postpartum hemorrhage and need for intervention. J Matern Fetal Neonatal Med. 2017:1-241.
22. Shamshirsaz AA, Fox KA, Erfani H, et al. Multidisciplinary team learning in the management of the morbidly adherent placenta: outcome improvements over time. Am J Obstet Gynecol. 2017;216:612 e1- e5.
23. Holtz RS. The control of postpartum hemorrhage by the intrauterine balloon. Am J Obstet Gynecol. 1951;62:450-1.
24. Dildy GA, Belfort MA, Adair CD, et al. Initial experience with a dual-balloon catheter for the management of postpartum hemorrhage. Am J Obstet Gynecol. 2014;210:136 e1-6.
25. Howard TF, Grobman WA. The relationship between timing of postpartum hemorrhage interventions and adverse outcomes. Am J Obstet Gynecol. 2015;213:239 e1-3.
26. Revert M, Rozenberg P, Cottenet J, Quantin C. Intrauterine balloon tamponade for severe postpartum hemorrhage. Obstet Gynecol. 2018;131:143-9.
27. B-Lynch C, Coker A, Lawal AH, Abu J, Cowen MJ. The B-Lynch surgical technique for the control of massive postpartum haemorrhage: an alternative to hysterectomy? Five cases reported. Br J Obstet Gynaecol. 1997;104:372-5.
28. Antony KM, Dildy GA, 3rd. Postpartum hemorrhage: the role of the Maternal-Fetal Medicine specialist in enhancing quality and patient safety. Semin Perinatol. 2013;37:246-56.
29. Mallaiah S, Barclay P, Harrod I, Chevannes C, Bhalla A. Introduction of an algorithm for ROTEM-guided fibrinogen concentrate administration in major obstetric haemorrhage. Anaesthesia. 2015;70:166-75.
30. Collaborators WT. Effect of early tranexamic acid administration on mortality, hysterectomy, and other morbidities in women with post-partum haemorrhage (WOMAN): an international, randomised, double-blind, placebo-controlled trial. Lancet. 2017;389:2105-16.
31. Pacheco LD, Hankins GDV, Saad AF, Costantine MM, Chiossi G, Saade GR. Tranexamic Acid for the Management of Obstetric Hemorrhage. Obstet Gynecol. 2017;130:765-9.
32. Babcock WW. Resuscitation during anesthesia. Anesthesia and Analgesia 1924:208-13.
33. Quality patient care in labor and delivery: a call to action. 2011. (Accessed 4 February 2018, at https://www.acog.org/-/media/Departments/Patient-Safety-and-Quality-Improvement/Call-to-Action-Paper.pdf?dmc=1&ts=20180204T2051393669.)
34. Deering S, Rowland J. Obstetric emergency simulation. Semin Perinatol. 2013;37:179-88.
35. Callaghan WM, Grobman WA, Kilpatrick SJ, Main EK, D’Alton M. Facility-based identification of women with severe maternal morbidity: it is time to start. Obstet Gynecol. 2014;123:978-81.
36. Severe Maternal Morbidity: Clarification of the New Joint Commission Sentinel Event Policy. 2015. (Accessed 3 February 2018, at https://www.acog.org/About-ACOG/News-Room/Statements/2015/Severe-Maternal-Morbidity-Clarification-of-the-New-Joint-Commission-Sentinel-Event-Policy.)