- Email: [email protected]
Strategies for Reducing Maternal Mortality
Strategies for Reducing Maternal Mortality Steven L. Clark, MD The maternal death rate in the United States has shown no improvement in several decades and may be increasing. On the other hand, hospital systems that have instituted comprehensive programs directed at the prevention of maternal mortality have demonstrated rates that are half of the national average. These programs have emphasized the reduction of variability in the provision of care through the use of standard protocols, reliance on checklists instead of memory for critical processes, and an approach to peer review that emphasizes systems change. In addition, elimination of a small number of repetitive errors in the management of hypertension, postpartum hemorrhage, pulmonary embolism, and cardiac disease will contribute significantly to a reduction in maternal mortality. Attention to these general principles and specific error reduction strategies will be of benefit to every practitioner and more importantly to the patients we serve. Semin Perinatol 36:42-47 © 2012 Elsevier Inc. All rights reserved. KEYWORDS cesarean delivery, maternal mortality, patient safety
D
espite dramatic advances in blood banking and antimicrobial and antihypertensive therapies, the development of safe and effective anesthetic and anticoagulation techniques and the availability of various sophisticated approaches to hemodynamic monitoring of critically ill patients, maternal mortality rates have not declined in the United States for more than three decades1-4 (Fig. 1). The major traditional causes of maternal death— hemorrhage, hypertension, and thromboembolism—remain prominent in contemporary series.1-4 However, a reduction in the absolute frequency of these potentially preventable conditions as causes of death has led to an increasing importance of unpreventable events such as amniotic fluid embolism.1-6 (Table 1). Further, improved survival of infants born with congenital heart disease in the late 20th century has led to an increasing number of women of childbearing age with corrected, or partially corrected, cardiac anomalies that pose new challenges to the 21st-century obstetrician. In contrast, anesthesia-related maternal deaths in the United States have declined by 60% since 1979; currently, the risk of anesthesia related death is approximately 1.2 per 1 million live births.7 This review will focus on strategies that may be undertaken both by individual clinicians and by hospitals and hospital systems to reduce maternal deaths. The discussion will include both general principles of patient safety and specific clinical
Hospital Corporation of America, Nashville, TN. No reprints available. Address reprint requests to Steven L. Clark, MD, 217 Melrose Rd, PO Box 404, Twin Bridges, MT 59754. E-mail: [email protected]
42
0146-0005/12/$-see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1053/j.semperi.2011.09.009
approaches to preventing maternal death. We will also review the somewhat complex and confusing role of cesarean delivery in contributing to, and preventing, maternal death.
Definitions Maternal deaths include those occurring during pregnancy or in the first 42 days post partum. These conditions have traditionally been classified as follows1,8:
Direct Maternal Deaths Deaths attributable to complications of pregnancy itself. Examples include deaths due to preeclampsia or postpartum hemorrhage.
Indirect Maternal Deaths Deaths attributable to the confounding effects of pregnancy on preexisting maternal medical conditions. Examples include decompensation due to preexisting cardiac disease or intracranial aneurysm.
Nonmaternal Deaths Deaths occurring during pregnancy or the puerperium but unrelated in any way to pregnancy. Examples include motor vehicle accidents or homicide. Using a different classification system, the World Health Organization excludes “nonmaternal” deaths from calculations of maternal mortality, and uses the more general term
Strategies for reducing maternal mortality
43 ● ● ●
Figure 1 Maternal mortality in the United States.
“pregnancy-related death” to define those events traditionally termed “direct, indirect, and nonmaternal” deaths.5 In comparing maternal death rates, it is critical to consider the definitions used; nonmaternal deaths are not counted in some series, yet may account for as many as 20% of maternal deaths in series that use the more comprehensive definition.1 In addition, it is important to realize the difficulty in classifying some causes of death— could a case of postpartum suicide or drug overdose apparently unrelated to pregnancy actually have its origin in postpartum stress or depression?
Incidence Overall, the maternal death rate in the United States has remained stable for several decades at about 9-10 deaths per 100,000 pregnancies (Fig. 1). A recent report suggesting an increase in maternal death rate to 13-14 per 100,000 pregnancies in the years 1998-2005 is of concern, but may be simply due to changes in definitions and reporting procedures.2-6 In underdeveloped countries, rates of maternal death remain much higher. However, direct comparisons of maternal death rates in developed and undeveloped countries are of little value owing to differences in definitions and significant problems with underreporting in undeveloped areas. Importantly, some hospital systems that have instituted comprehensive patient safety initiatives have shown significantly lower rates of maternal death.1,9,10 The Hospital Corporation of America recently reported a maternal death rate of 6.5 per 100,000 pregnancies—less than half of the most recently reported figures for the United States, despite the inclusion in this lower rate of deaths traditionally classified as “nonmaternal.”1 Despite the best care available, only onethird of maternal deaths in the United States are preventable, given our current state of medical knowledge and within the confines of our current health care delivery system.1
General Approaches to Patient Safety The principles of patient safety outlined by the Institute of Medicine a decade ago are valuable starting points for programs aimed at the prevention of maternal death.9-12 Some of the most critical processes include the following:
The elimination of variability in the provision of care through the development of standard protocols. Increased reliance on checklists instead of memory for critical procedures. An approach to peer review and quality improvement that emphasizes systems change to prevent error, rather than a punitive approach to those involved in adverse outcomes.
Examples of such protocols that have proven useful in preventing maternal mortality are shown in Table 2. Several key features of both of these protocols are typical of effective approaches to the prevention of catastrophic outcomes, and include the following: 1. Aggressive identification of developing problems before the patient becomes critically ill. 2. Involvement and empowerment of all health care providers to identify potentially lethal complications and initiate independent corrective action. 3. Reduction in process variation, ensuring that in a critical situation, all team members will know what each other provider has done, is doing, and is about to do. 4. Specificity in treatment protocols, thus eliminating the need to rely on memory, and reduction in the “normalization of deviance,” a term used to describe reliance on anecdotal experience rather than evidence-based medicine. 5. The ready use of consultants (both within and outside of a given specialty). This approach does not imply incompetence of the primary provider, but rather recognition of the fallibility of any single human, regardless of intelligence or experience, in the face of an uncommon and potentially catastrophic situation. Two heads are often better than one.
Individual Practice Patterns A detailed examination of the pathophysiology and treatment of conditions commonly leading to maternal death is
Table 1 Causes of Maternal Mortality in the United States (2000-2006)* Cause of Death
%
Complications of preeclampsia Amniotic fluid embolism Obstetric hemorrhage Pulmonary thromboembolism Cardiac disease Nonobstetric infection Accident/suicide Obstetric infection Medication error or reaction Ectopic pregnancy Other Total
15 14 11 11 11 7 7 7 5 1 11 100
*Based on 1.5 million pregnancies.1
S.L. Clark
44 Table 2 Protocol for treatment of hypertensive crisis in pregnancy
beyond the scope of this treatise, but may be found in other excellent texts.8,13,14 Rather, the ensuing discussion will focus on a series of specific errors that often lead to maternal death, and steps that may be taken to avoid such outcomes. This list is based on a recent detailed review of preventable and nonpreventable causes of maternal mortality, as well as the author’s experience in safety oversight of a large, multistate hospital system and many years of
consultation with risk management and malpractice insurance carriers.
Hypertension Three key errors lead to death in women with preeclampsia, or preeclampsia superimposed on chronic hypertension. The latter group of hypertensive women seems to be at particular risk, perhaps due to longstanding chronic vascular disease.
Strategies for reducing maternal mortality 1. The provider does not appropriately respond to abnormal blood pressures in the clinic and does not engage in appropriate evaluation of new or significantly worsening hypertension. A blood pressure of 140/90 in a previously normotensive woman, or a significant increase in blood pressure in a previously hypertensive woman, always requires some degree of further evaluation; “return to clinic in 1 week” does not generally constitute such an evaluation. If the changes are mild and not associated with other indicia of preeclampsia, repeat blood pressure evaluations in the clinic and close follow-up may be all that is required. However, with more marked elevations of blood pressure, or the occurrence of other signs or symptoms of preeclampsia, hospitalization for a full evaluation may be necessary both for a full evaluation of the current condition and to rule out fulminate worsening of the disease. While mild cases of preeclampsia may sometimes be managed on an outpatient basis, most cases will require both inpatient evaluation and either inpatient management or delivery. 2. The provider does not respond to severe hypertension during labor or the immediate postpartum period, especially if blood pressures are not consistently above 160/110 mm Hg. Markedly elevated systolic or diastolic pressures alone may also be confusing to both nurses who are expected to report hypertension and to physicians who must treat it. As a rule, an aggressive approach to blood pressure control is in the patient’s best interest, even if severely elevated pressures are not consistently seen (see Table 2). While the goal of acute peripartum antihypertensive therapy is not the normalization of blood pressure, lowering of either systolic or diastolic blood pressure is suggested for any woman whose levels exceed either of the above values. Twenty milligrams of intravenous labetalol will not be harmful to a woman with either a systolic pressure ⬎160 mm Hg or a diastolic pressure ⬎105 mm Hg, even if such pressures are only intermittently seen. Adverse events may be prevented using recently developed checklistbased algorithms for team management of hypertensive crisis in pregnancy (Table 2). 3. Failure to recognize and treat pulmonary edema. While pulmonary edema is uncommon in women with severe preeclampsia, it is a relative common cause of death in women dying of complications of preeclampsia. Many antepartum nurses have never independently recognized pulmonary edema and most obstetricians have little experience in the treatment of this condition. Any woman with preeclampsia complaining of shortness of breath or cough, or with significant changes in pulse oximetry or respiratory rate, should have a prompt and thorough evaluation. In most cases, this includes chest x-ray and careful monitoring of maternal oxygenation status. When recognized, many women with pulmonary edema will be well served if managed in conjunction with a maternal-fetal medicine specialist, anesthesiologist, or pulmonologist.
45
Hemorrhage Occasional maternal deaths from hemorrhage are not preventable. However, a recent review of maternal deaths in a delivery population of approximately 1.5 million from the United States during 2000-2006 concluded that all deaths from hemorrhage were potentially preventable with improved care.1 The following common errors are seen: 1. Failure to use a working diagnosis in cases of hemorrhage. It is critical to realize that postpartum hemorrhage is a clinical sign, not a diagnosis! This sign may be caused by uterine atony, lacerations, retained placenta, including placenta accreta, and occasionally, coagulopathy. Each of these conditions requires specific therapy. Taking a shotgun approach (for example, continued use of uterotonic agents in a uterus noted to be firmly contracted) may result in missed diagnosis and death. 2. Continued attempts at the same (unsuccessful) approach to stopping hemorrhage. This is especially commonly seen with the administration of uterotonic agents for actual or presumed uterine atony. A rapidly hemorrhaging patient can receive full courses of oxytocin, Methergine (Novartis, Basel, Switzerland), and prostaglandins, as well as a careful inspection of the genital tract for lacerations and uterine exploration (manual or with curettage) to exclude retained placenta within 30 minutes—if heavy bleeding continues, operative intervention is often indicated. Failure to act decisively in the face of severe, ongoing hemorrhage may lead to maternal death. 3. Insufficient or slow replacement of blood and clotting components in the patient with massive ongoing hemorrhage. In the patient with ongoing hemorrhage, early preparation of blood and components is essential. After the replacement of 4-6 U of packed red blood cells in the face of ongoing bleeding, fibrinogen and platelets should be assessed and replaced appropriately according to standard massive transfusion protocols. 4. Failure to adequately prepare for placenta accreta. This condition is usually seen in women with one or more prior cesarean scars and a concurrent placenta previa.15 Such women should be evaluated and delivered in a referral center with the immediate availability of both multiple surgical subspecialists and massive amounts of blood and components.16 Few conditions in obstetrics are more difficult to manage than a placenta percreta with invasion of multiple abdominal organs—if your center does not regularly operate on women with placental accreta, you should probably not do it at all.
Pulmonary Thromboembolism In a recent review of maternal deaths, pulmonary thromboembolism was the single cause of death most amenable to reduction by systematic change in practice.1 We and others recommend the routine use of pneumatic compression devices (PCDs) for all women undergoing cesarean delivery.1,10,17 Placement and activation should ideally precede the beginning of surgery, and should continue until the patient is
46 Table 3 Protocol for treatment of postpartum hemorrhage
S.L. Clark
Strategies for reducing maternal mortality fully ambulatory (usually ⬍24 hours). Preliminary results of such policies suggest an improvement in outcomes and a reduction in deaths from pulmonary embolism.10,17
Cardiac Disease No single type of cardiac disease in pregnancy accounts for a significant number of maternal deaths, although as a whole, cardiac disease remains a relatively frequent cause of death.1-5 Proper management of women with complex cardiac disease generally involves multiple specialists, including maternal fetal medicine, anesthesiology, and cardiology as well as experienced nursing care. The key to prevention of mortality is usually proper counseling and the judicious use of pregnancy termination in early pregnancy, as well as careful planning for delivery. This often includes delivery in a tertiary care center. Invasive hemodynamic monitoring is sometimes useful during the peripartum period.
The Role of Cesarean Delivery in Maternal Death For years, it has been recognized that women delivered by cesarean experience death at a rate up to 10 times higher than those delivered vaginally.1 However, a common error in earlier studies involves the assumption that the cesarean is causative, rather than simply having been performed for the indication that actually led to maternal death. A recent series from the United States involved careful analysis of medical records by a number of recognized authorities in maternal critical care.1 This analysis suggested that the vast majority of deaths associated with cesarean are not due to the procedure itself but due to the underlying condition that led to the cesarean. These authors estimated that approximately 20 women die each year in the United States due to complications of cesarean delivery. To put this into context, a woman is 7 times more likely to get leprosy in the United States than to die as a result of cesarean delivery.18 Certainly, the number of babies saved by the same operation is orders of magnitude greater. Further, because a condition as common as an obstructed labor in nature often results in both fetal and maternal death, it is clear that cesarean delivery saves far more maternal lives annually than are lost owing to this operation. It also appears that the excess deaths causally attributed to cesarean vs vaginal delivery are primarily due to excess deaths from postoperative pulmonary embolism.1 If one assumes that PCDs are as effective in cesarean deliveries as in other types of major surgery, the adoption of universal PCD use for all cesarean deliveries would eliminate the increased statistical risk of death due to cesarean in the United States.1 (Table 3).
47
Conclusions Most maternal deaths in the United States are not preventable. Nevertheless, that fraction of preventable deaths that continue to occur is especially tragic. There has been no significant decline in the rate of maternal deaths in the United States in several decades. Widespread adoption of general principles of patient safety by the obstetric profession and careful attention to those specific errors discussed above may help alter this trend favorably in future years.
References 1. Clark SL, Belfort MA, Dildy GA, et al: Maternal death in the 21st century. Prevention and relationship to cesarean delivery. Am J Obstet Gynecol 199:36.e1-36.e5, 2008 2. Berg CJ, Callaghan WM, Syverson C, et al: Pregnancy-related mortality in the United States, 1998-2005. Obstet Gynecol 116:1302-1309, 2010 3. Khan KS, Wojkyla D, Say L, et al: WHO analysis of causes of maternal death: A systematic review. Lancet 367:1066-1074, 2006 4. Joint Commission Sentinel Event Alert 44, 2010. Available at: http:// www.jointcommission.org/assets/1/18/SEA_44.PDF. Accessed April 22, 2011 5. Hoyert DL: Maternal mortality and related concepts. National Center for Health Statistics. Vital Health Stat 3, 2007 6. Dildy GA, Belfort MA, Clark SL: Anaphylactoid syndrome of pregnancy (amniotic fluid embolism), in Belfort MA, Saade GA, Foley MA, et al (eds): Critical Care Obstetrics, 5th ed. Oxford, UK, John Wiley and Sons, 2010 7. Hawkins JC, Chang J, Palmer SK, et al: Anesthesia-related maternal mortality in the U.S. 1998-2005. Obstet Gynecol 116:1302-1309, 2010 8. Cunningham FG, Leveno KJ, Bloom SL, et al: Williams Obstetrics, 22nd ed. New York, NY, McGraw-Hill, 2005 9. Clark SL, Belfort MA, Meyers JA, et al: Improved outcomes, fewer cesarean deliveries and reduced litigation: Results of a new paradigm in patient safety. Am J Obstet Gynecol 199:105.e1-105.e7, 2008 10. Clark SL, Meyers JA, Frye DK, et al: Patient safety in obstetrics: The Hospital Corporation of America experience. Am J Obstet Gynecol 204:283-287, 2011 11. Kohn LT, Corrigan JM, Donaldson MS. (eds): To Err Is Human. Washington, DC, Institute of Medicine, National Academy Press, 2000 12. Crossing the Quality Chasm: A New Health System for the 21st Century. Washington, DC, The Institute of Medicine, National Academy Press, 2001 13. Belfort MA, Saade GA, Foley MA, et al (eds): Critical Care Obstetrics, 5th ed. John Wiley and Sons, 2010 14. Creasy RK, Resnik R, Iams JD, et al: Maternal-Fetal Medicine, 6th ed. Philadelphia, PA, Elsevier, 2009 15. Clark SL, Koonings PP, Phelan JP: Placenta previa/accreta and prior cesarean section. Obstet Gynecol 66:89-92, 1985 16. Wright JD, Herzog WT, Shah N, et al: Regionalization of care for obstetric hemorrhage and its effect on maternal mortality. Obstet Gynecol 115:1194-2000, 2010 17. Grunebaum A, Chervenak F, Skupski D: Effect of a comprehensive obstetric patient safety program on compensation payments and sentinel events. Am J Obstet Gynecol 204:97-105, 2011 18. Storrs C: Armadillos spreading leprosy to humans. CNN Health. Available at: http://www.cnn.com/2011/HEALTH/04/27/armadillos.spreading. leprosy/index.html. Accessed April 28, 2011
D
espite dramatic advances in blood banking and antimicrobial and antihypertensive therapies, the development of safe and effective anesthetic and anticoagulation techniques and the availability of various sophisticated approaches to hemodynamic monitoring of critically ill patients, maternal mortality rates have not declined in the United States for more than three decades1-4 (Fig. 1). The major traditional causes of maternal death— hemorrhage, hypertension, and thromboembolism—remain prominent in contemporary series.1-4 However, a reduction in the absolute frequency of these potentially preventable conditions as causes of death has led to an increasing importance of unpreventable events such as amniotic fluid embolism.1-6 (Table 1). Further, improved survival of infants born with congenital heart disease in the late 20th century has led to an increasing number of women of childbearing age with corrected, or partially corrected, cardiac anomalies that pose new challenges to the 21st-century obstetrician. In contrast, anesthesia-related maternal deaths in the United States have declined by 60% since 1979; currently, the risk of anesthesia related death is approximately 1.2 per 1 million live births.7 This review will focus on strategies that may be undertaken both by individual clinicians and by hospitals and hospital systems to reduce maternal deaths. The discussion will include both general principles of patient safety and specific clinical
Hospital Corporation of America, Nashville, TN. No reprints available. Address reprint requests to Steven L. Clark, MD, 217 Melrose Rd, PO Box 404, Twin Bridges, MT 59754. E-mail: [email protected]
42
0146-0005/12/$-see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1053/j.semperi.2011.09.009
approaches to preventing maternal death. We will also review the somewhat complex and confusing role of cesarean delivery in contributing to, and preventing, maternal death.
Definitions Maternal deaths include those occurring during pregnancy or in the first 42 days post partum. These conditions have traditionally been classified as follows1,8:
Direct Maternal Deaths Deaths attributable to complications of pregnancy itself. Examples include deaths due to preeclampsia or postpartum hemorrhage.
Indirect Maternal Deaths Deaths attributable to the confounding effects of pregnancy on preexisting maternal medical conditions. Examples include decompensation due to preexisting cardiac disease or intracranial aneurysm.
Nonmaternal Deaths Deaths occurring during pregnancy or the puerperium but unrelated in any way to pregnancy. Examples include motor vehicle accidents or homicide. Using a different classification system, the World Health Organization excludes “nonmaternal” deaths from calculations of maternal mortality, and uses the more general term
Strategies for reducing maternal mortality
43 ● ● ●
Figure 1 Maternal mortality in the United States.
“pregnancy-related death” to define those events traditionally termed “direct, indirect, and nonmaternal” deaths.5 In comparing maternal death rates, it is critical to consider the definitions used; nonmaternal deaths are not counted in some series, yet may account for as many as 20% of maternal deaths in series that use the more comprehensive definition.1 In addition, it is important to realize the difficulty in classifying some causes of death— could a case of postpartum suicide or drug overdose apparently unrelated to pregnancy actually have its origin in postpartum stress or depression?
Incidence Overall, the maternal death rate in the United States has remained stable for several decades at about 9-10 deaths per 100,000 pregnancies (Fig. 1). A recent report suggesting an increase in maternal death rate to 13-14 per 100,000 pregnancies in the years 1998-2005 is of concern, but may be simply due to changes in definitions and reporting procedures.2-6 In underdeveloped countries, rates of maternal death remain much higher. However, direct comparisons of maternal death rates in developed and undeveloped countries are of little value owing to differences in definitions and significant problems with underreporting in undeveloped areas. Importantly, some hospital systems that have instituted comprehensive patient safety initiatives have shown significantly lower rates of maternal death.1,9,10 The Hospital Corporation of America recently reported a maternal death rate of 6.5 per 100,000 pregnancies—less than half of the most recently reported figures for the United States, despite the inclusion in this lower rate of deaths traditionally classified as “nonmaternal.”1 Despite the best care available, only onethird of maternal deaths in the United States are preventable, given our current state of medical knowledge and within the confines of our current health care delivery system.1
General Approaches to Patient Safety The principles of patient safety outlined by the Institute of Medicine a decade ago are valuable starting points for programs aimed at the prevention of maternal death.9-12 Some of the most critical processes include the following:
The elimination of variability in the provision of care through the development of standard protocols. Increased reliance on checklists instead of memory for critical procedures. An approach to peer review and quality improvement that emphasizes systems change to prevent error, rather than a punitive approach to those involved in adverse outcomes.
Examples of such protocols that have proven useful in preventing maternal mortality are shown in Table 2. Several key features of both of these protocols are typical of effective approaches to the prevention of catastrophic outcomes, and include the following: 1. Aggressive identification of developing problems before the patient becomes critically ill. 2. Involvement and empowerment of all health care providers to identify potentially lethal complications and initiate independent corrective action. 3. Reduction in process variation, ensuring that in a critical situation, all team members will know what each other provider has done, is doing, and is about to do. 4. Specificity in treatment protocols, thus eliminating the need to rely on memory, and reduction in the “normalization of deviance,” a term used to describe reliance on anecdotal experience rather than evidence-based medicine. 5. The ready use of consultants (both within and outside of a given specialty). This approach does not imply incompetence of the primary provider, but rather recognition of the fallibility of any single human, regardless of intelligence or experience, in the face of an uncommon and potentially catastrophic situation. Two heads are often better than one.
Individual Practice Patterns A detailed examination of the pathophysiology and treatment of conditions commonly leading to maternal death is
Table 1 Causes of Maternal Mortality in the United States (2000-2006)* Cause of Death
%
Complications of preeclampsia Amniotic fluid embolism Obstetric hemorrhage Pulmonary thromboembolism Cardiac disease Nonobstetric infection Accident/suicide Obstetric infection Medication error or reaction Ectopic pregnancy Other Total
15 14 11 11 11 7 7 7 5 1 11 100
*Based on 1.5 million pregnancies.1
S.L. Clark
44 Table 2 Protocol for treatment of hypertensive crisis in pregnancy
beyond the scope of this treatise, but may be found in other excellent texts.8,13,14 Rather, the ensuing discussion will focus on a series of specific errors that often lead to maternal death, and steps that may be taken to avoid such outcomes. This list is based on a recent detailed review of preventable and nonpreventable causes of maternal mortality, as well as the author’s experience in safety oversight of a large, multistate hospital system and many years of
consultation with risk management and malpractice insurance carriers.
Hypertension Three key errors lead to death in women with preeclampsia, or preeclampsia superimposed on chronic hypertension. The latter group of hypertensive women seems to be at particular risk, perhaps due to longstanding chronic vascular disease.
Strategies for reducing maternal mortality 1. The provider does not appropriately respond to abnormal blood pressures in the clinic and does not engage in appropriate evaluation of new or significantly worsening hypertension. A blood pressure of 140/90 in a previously normotensive woman, or a significant increase in blood pressure in a previously hypertensive woman, always requires some degree of further evaluation; “return to clinic in 1 week” does not generally constitute such an evaluation. If the changes are mild and not associated with other indicia of preeclampsia, repeat blood pressure evaluations in the clinic and close follow-up may be all that is required. However, with more marked elevations of blood pressure, or the occurrence of other signs or symptoms of preeclampsia, hospitalization for a full evaluation may be necessary both for a full evaluation of the current condition and to rule out fulminate worsening of the disease. While mild cases of preeclampsia may sometimes be managed on an outpatient basis, most cases will require both inpatient evaluation and either inpatient management or delivery. 2. The provider does not respond to severe hypertension during labor or the immediate postpartum period, especially if blood pressures are not consistently above 160/110 mm Hg. Markedly elevated systolic or diastolic pressures alone may also be confusing to both nurses who are expected to report hypertension and to physicians who must treat it. As a rule, an aggressive approach to blood pressure control is in the patient’s best interest, even if severely elevated pressures are not consistently seen (see Table 2). While the goal of acute peripartum antihypertensive therapy is not the normalization of blood pressure, lowering of either systolic or diastolic blood pressure is suggested for any woman whose levels exceed either of the above values. Twenty milligrams of intravenous labetalol will not be harmful to a woman with either a systolic pressure ⬎160 mm Hg or a diastolic pressure ⬎105 mm Hg, even if such pressures are only intermittently seen. Adverse events may be prevented using recently developed checklistbased algorithms for team management of hypertensive crisis in pregnancy (Table 2). 3. Failure to recognize and treat pulmonary edema. While pulmonary edema is uncommon in women with severe preeclampsia, it is a relative common cause of death in women dying of complications of preeclampsia. Many antepartum nurses have never independently recognized pulmonary edema and most obstetricians have little experience in the treatment of this condition. Any woman with preeclampsia complaining of shortness of breath or cough, or with significant changes in pulse oximetry or respiratory rate, should have a prompt and thorough evaluation. In most cases, this includes chest x-ray and careful monitoring of maternal oxygenation status. When recognized, many women with pulmonary edema will be well served if managed in conjunction with a maternal-fetal medicine specialist, anesthesiologist, or pulmonologist.
45
Hemorrhage Occasional maternal deaths from hemorrhage are not preventable. However, a recent review of maternal deaths in a delivery population of approximately 1.5 million from the United States during 2000-2006 concluded that all deaths from hemorrhage were potentially preventable with improved care.1 The following common errors are seen: 1. Failure to use a working diagnosis in cases of hemorrhage. It is critical to realize that postpartum hemorrhage is a clinical sign, not a diagnosis! This sign may be caused by uterine atony, lacerations, retained placenta, including placenta accreta, and occasionally, coagulopathy. Each of these conditions requires specific therapy. Taking a shotgun approach (for example, continued use of uterotonic agents in a uterus noted to be firmly contracted) may result in missed diagnosis and death. 2. Continued attempts at the same (unsuccessful) approach to stopping hemorrhage. This is especially commonly seen with the administration of uterotonic agents for actual or presumed uterine atony. A rapidly hemorrhaging patient can receive full courses of oxytocin, Methergine (Novartis, Basel, Switzerland), and prostaglandins, as well as a careful inspection of the genital tract for lacerations and uterine exploration (manual or with curettage) to exclude retained placenta within 30 minutes—if heavy bleeding continues, operative intervention is often indicated. Failure to act decisively in the face of severe, ongoing hemorrhage may lead to maternal death. 3. Insufficient or slow replacement of blood and clotting components in the patient with massive ongoing hemorrhage. In the patient with ongoing hemorrhage, early preparation of blood and components is essential. After the replacement of 4-6 U of packed red blood cells in the face of ongoing bleeding, fibrinogen and platelets should be assessed and replaced appropriately according to standard massive transfusion protocols. 4. Failure to adequately prepare for placenta accreta. This condition is usually seen in women with one or more prior cesarean scars and a concurrent placenta previa.15 Such women should be evaluated and delivered in a referral center with the immediate availability of both multiple surgical subspecialists and massive amounts of blood and components.16 Few conditions in obstetrics are more difficult to manage than a placenta percreta with invasion of multiple abdominal organs—if your center does not regularly operate on women with placental accreta, you should probably not do it at all.
Pulmonary Thromboembolism In a recent review of maternal deaths, pulmonary thromboembolism was the single cause of death most amenable to reduction by systematic change in practice.1 We and others recommend the routine use of pneumatic compression devices (PCDs) for all women undergoing cesarean delivery.1,10,17 Placement and activation should ideally precede the beginning of surgery, and should continue until the patient is
46 Table 3 Protocol for treatment of postpartum hemorrhage
S.L. Clark
Strategies for reducing maternal mortality fully ambulatory (usually ⬍24 hours). Preliminary results of such policies suggest an improvement in outcomes and a reduction in deaths from pulmonary embolism.10,17
Cardiac Disease No single type of cardiac disease in pregnancy accounts for a significant number of maternal deaths, although as a whole, cardiac disease remains a relatively frequent cause of death.1-5 Proper management of women with complex cardiac disease generally involves multiple specialists, including maternal fetal medicine, anesthesiology, and cardiology as well as experienced nursing care. The key to prevention of mortality is usually proper counseling and the judicious use of pregnancy termination in early pregnancy, as well as careful planning for delivery. This often includes delivery in a tertiary care center. Invasive hemodynamic monitoring is sometimes useful during the peripartum period.
The Role of Cesarean Delivery in Maternal Death For years, it has been recognized that women delivered by cesarean experience death at a rate up to 10 times higher than those delivered vaginally.1 However, a common error in earlier studies involves the assumption that the cesarean is causative, rather than simply having been performed for the indication that actually led to maternal death. A recent series from the United States involved careful analysis of medical records by a number of recognized authorities in maternal critical care.1 This analysis suggested that the vast majority of deaths associated with cesarean are not due to the procedure itself but due to the underlying condition that led to the cesarean. These authors estimated that approximately 20 women die each year in the United States due to complications of cesarean delivery. To put this into context, a woman is 7 times more likely to get leprosy in the United States than to die as a result of cesarean delivery.18 Certainly, the number of babies saved by the same operation is orders of magnitude greater. Further, because a condition as common as an obstructed labor in nature often results in both fetal and maternal death, it is clear that cesarean delivery saves far more maternal lives annually than are lost owing to this operation. It also appears that the excess deaths causally attributed to cesarean vs vaginal delivery are primarily due to excess deaths from postoperative pulmonary embolism.1 If one assumes that PCDs are as effective in cesarean deliveries as in other types of major surgery, the adoption of universal PCD use for all cesarean deliveries would eliminate the increased statistical risk of death due to cesarean in the United States.1 (Table 3).
47
Conclusions Most maternal deaths in the United States are not preventable. Nevertheless, that fraction of preventable deaths that continue to occur is especially tragic. There has been no significant decline in the rate of maternal deaths in the United States in several decades. Widespread adoption of general principles of patient safety by the obstetric profession and careful attention to those specific errors discussed above may help alter this trend favorably in future years.
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