Current Women's Health Reviews - Volume 7, Issue 2, 2011

Pregnant or postpartum patients requiring intensive care unit (ICU) admission account for less than 2% of the whole ICU population in developed countries, but they can reach up to 10-15% in developing regions. However, the great impact of these patients' admission to the ICU is more important than the actual number of patients admitted. Critically ill Obstetric patients represent a unique group of patients with particular characteristics. Their normal physiology is different from that of non-pregnant women. In addition, they are exposed to common diseases such as community acquired pneumonia or urinary tract infection; but they also suffered from pregnancy-related disorders not completely known by many critical care physicians. On the other hand, these patients are young, usually healthy and they carry a baby or have just delivered, which makes the process of being critically ill completely unexpected. Moreover, they frequently have other children to look after. When a mother is critically ill or eventually dies the whole house welfare is compromised. Maternal death increases the risk of child death and malnourishment and decreases the probability of school enrolment. Maternal mortality is a rare event in developed countries, but is still frequent in developing regions, where women die of completely preventable diseases such as septic abortion. The primary objective of the current supplement was to review the most frequent causes of admission of obstetric patients to the Intensive Care Unit, in order to help physicians with their management. The secondary objective was to cast some light on the most important causes of maternal mortality worldwide. In this way, we hope to contribute to build up knowledge about this important health problem, with the aim of promoting in some way its prevention.

This review briefly updates issues related to physiology of pregnancy and peripartum period, maternal mortality and obstetric ICU admissions. Maternal mortality (MM) is still a frequent event, occurring mainly in developing countries. Causes of MM vary: in developed countries, complications of anaesthesia/caesarean section (20%), hypertensive disorders (16%), embolism (15%) and hemorrhage (13%) prevail. In developing countries, obstetric hemorrhage, hypertensive disorders and sepsis are the commonest. Other causes are region-specific, as HIV-AIDS in Africa, anemia and obstructed labor in Asia, and unsafe abortion in Latin America and the Caribbean. Obstetric intensive care unit (ICU) requirement can be considered an indicator of severe maternal morbidity in itself. In high and low-income countries, obstetric patients represent <5% and 10-15% of ICU admissions, respectively; usually occur in the post-partum period, and reasons are obstetric over medical. The most common obstetric causes are: hypertensive disorders, hemorrhage, and sepsis of pelvic origin, with regional variations in incidences. Medical causes of admission, however, show great disparity. Mechanical ventilation is required in 20-65% of patients, and pulmonary artery catheter is seldom used. ICU maternal mortality is <5% in high-income countries, but might reach between 10-60% in low-income countries. APACHE II score usually overpredicts ICU mortality.

Preeclampsia is still one of the leading causes of maternal and fetal morbidity and mortality. Improved understanding of the etiology of the disorder has not yet led us to a treatment paradigm which improves maternal and fetal morbidity and mortality in all instances. The degree of severity of preeclampsia is a continuum. However, based on certain criteria and in an attempt to de prevent bad outcome the presentation of the disease is often defined as “mild” or “severe”. Intensive care of mothers with severe preeclampsia and associated complications is not uncommon, and often involves women who lack prenatal care or have delayed diagnosis. Maternal complications can be many and include abrutio placenta, disseminated intravascular coagulation, the syndrome of hemolysis, elevated liver enzymes, low platelets (HELLP), pulmonary edema, eclampsia, stroke, visual loss, posterior reversible leukoencephalopathy, and death. The majority of women recover from severe preeclampsia without sequelae, but a small percentage will require intensive care to manage complications.

The HELLP syndrome (haemolysis, elevated liver enzymes, low platelet count) is a variant of the pre-eclampsia/eclampsia syndrome occurring in 10-20% of patients whose diseases are labelled as severe. Although the majority of cases of HELLP syndrome occur antepartum, the disease can present in the postpartum period, usually within 48 hours of delivery. Hypertension and proteinuria may not be detected in 10-20% of cases. As the HELLP syndrome and concurrent eclampsia have been implicated in as many as 5-6 of every 10 maternal deaths it is apparent that such patients require the expertise of a multidisciplinary team (e.g haematologist, maternal fetal medicine experts, and critical care specialists). There is no conclusive evidence supporting the use of high dose corticosteroids in the treatment of HELLP syndrome. Steroids for the use of accelerating fetal lung maturity and decreasing the high perinatal mortality associated with severe pre-eclampsia and the HELLP syndrome is however of proven benefit. The aetiology of pre-eclampsia complicated by the HELLP syndrome is unknown, but data from animal models suggest roles for circulating anti angiogenic proteins. The consensus is that delivery is followed by rapid return of the haematological system to normal. Pregnancies between 24-34 gestational weeks usually should, if possible, receive a standard corticosteroid course, followed by delivery. In pregnancies >35 weeks, rapid delivery alone suffices. Most clinicians would not attempt expectant management in gestations <24 weeks.

Obstetric haemorrhage refers to any bleeding that occurs during pregnancy, delivery or in the postpartum period. It is associated with maternal morbidity and remains the leading cause of direct maternal deaths in developing countries. Antepartum haemorrhage (APH) refers to any genital tract bleeding prior to the delivery of the baby. Identifiable causes of APH include placenta praevia, placental abruption, vasa praevia and local organic pathology such as genital tract tumours. The exact cause of APH remains uncertain in approximately 50% of patients. Postpartum haemorrhage (PPH) refers to excessive bleeding from the genital tract after the delivery of the baby and is termed primary when it occurs within the first 24 hours of birth. Common causes include atonic uterus, genital tract trauma, retained placental tissue and coagulopathy. Secondary PPH occurs after the first 24 hours and is due to retained products of conception and/or infection (endometritis). The management algorithm ‘HAEMOSTASIS’ has been proposed to aid the systematic management of postpartum haemorrhage. A multidisciplinary approach is essential to improve outcomes. Early diagnosis, timely institution of appropriate measures to arrest haemorrhage, replacement of blood volume (intravenous fluids), ensuring oxygen carrying capacity of blood (by blood transfusion) and correction of coagulopathy may help save lives.

The pregnant woman is at risk of several pregnancy-specific conditions that may cause respiratory failure, as well as many conditions that are aggravated by the pregnant state. These conditions include pulmonary edema secondary to preeclampsia, amniotic fluid embolism, ARDS due to pregnancy complications and other causes, as well as aspiration of gastric contents, venous thromboembolism and pre-existing heart disease. Management of these patients requires understanding of the altered maternal physiology and avoidance of harm to the fetus. While radiological procedures and drug therapy may compromise fetal wellbeing, the greatest risk is deterioration in the maternal condition resulting in fetal hypoxia. Little data exist to guide prolonged mechanical ventilation in the pregnant woman, but usual principles can be applied to optimize oxygenation, while avoiding maternal alkalosis. If the fetus is at a viable gestation and is at risk due to intractable maternal hypoxia, there may be a benefit to the fetus in delivery. However, delivery purely in an attempt to improve maternal oxygenation or ventilation is often not successful.

Unsafe abortion (UA) is still a main cause of maternal mortality in countries with restrictive abortion laws. Our objective was to review current concepts about septic abortion (SA), its epidemiology, diagnosis, management and prevention. A wide variety of methods for inducing abortion exist. Lastly, misoprostol has replaced more dangerous methods. Septic abortion is a polymicrobial ascending infection. It should be suspected in any young women presenting with lower abdominal pain, fever and vaginal bleeding, as well as with severe sepsis or septic shock. Broad-spectrum antibiotics and source control should be initiated promptly. Removal of retained products of conception should be performed as soon as possible. Indications for laparotomy are failure to respond to uterine evacuation and adequate treatment, uterine perforation with suspected bowel injury, pelvic and adnexal abscesses and clostridial myometritis. Indications for hysterectomy are a uterus of woody appearance or discolored, clostridial necrotizing myometritis, crepitation of the pelvic tissue and radiographic evidence of air within the uterine wall. Aggressive surgical wound debridement and hysterectomy should be performed whenever gas gangrene is present. Effective contraception has been shown to reduce UA but is not enough to cope with high fertility regulation demands. Legalized, safe and accessible abortion services are required.

Maternal sepsis remains a major preventable cause of morbidity and mortality worldwide. The current epidemic of obesity, diabetes, and cesarean delivery will most certainly increase the risk of infectious morbidity and mortality. Women who undergo cesarean are three times more likely to develop sepsis. Early recognition of cases and prompt treatment are essential to improve outcomes. Most cases of maternal sepsis are due to direct obstetrical causes and should be treated with broad spectrum antibiotics and source control measures. Early goal directed therapies should be initiated according to standardized protocols. Patients should be transferred to a critical care unit if feasible. Optimal care for the septic patient requires a multidisciplinary team with expertise in all relevant areas including critical care, infectious disease, maternal fetal medicine, obstetrics, anesthesia, pharmacology, and neonatology. This article reviews the epidemiology, microbiology, pathophysiology and treatment of obstetrical sepsis.

Pulmonary embolism (PE) is a leading cause of maternal mortality during pregnancy and following delivery. Pregnancy is associated with a variety of anatomical, hormonal and biochemical alterations that predispose towards venous thrombosis and PE. A high index of suspicion is critical in making the diagnosis, which can be confirmed by objective testing with lower extremity Doppler ultrasound, lung scintigraphy or CT angiography. Treatment in the acute setting typically includes intravenous UFH, subcutaneous LMWH or subcutaneous UFH, with transition to subcutaneous regimens for the duration of the pregnancy. Interventions in pregnant women with massive (hemodynamically unstable) PE include: positioning in a left lateral decubitus position, volume resuscitation, and supplemental oxygen. IVC filters may be helpful, as they can be for non-pregnant patients. Although experience is limited, systemic or catheter directed thrombolytic therapy have been reported to be successful in treatment of massive PE in pregnant patients with relatively low maternal and fetal mortality. Invasive therapies such as surgical embolectomy for severely ill pregnancy women with massive PE might be instituted depending on the patient acuity and the available resources and expertise.

During pregnancy, the risk of venous thromboembolism (VTE) increases 2-5 fold and pulmonary embolism (PE) remains a leading cause of maternal mortality in developed countries. For pregnant women with suspected deep vein thrombosis (DVT) or PE, the use of serial compression leg ultrasound (CUS) should be considered to exclude DVT whereas a normal ventilation perfusion lung scan likely excludes PE. A computer tomographic pulmonary angiogram (CTPA) could assist in ruling out PE in women who present with an abnormal chest radiograph. Low molecular weight heparins (LMWH) are the agents of choice for treatment and thromboprophylaxis of pregnant patients with VTE but appropriate dosing changes throughout pregnancy remain uncertain. Women with previously unprovoked VTE and those in whom VTE are provoked by previous pregnancies or use of oral contraceptive are at highest risk of VTE recurrence during pregnancy, and should be offered antepartum and postpartum thromboprophylaxis. On the other hand, women with prior VTE related to a transient risk factor would benefit from postpartum thromboprophylaxis. More research is needed to identify the absolute risk of VTE during pregnancy associated with more prevalent risk factors such as maternal age, obesity, and mode of delivery.

Peripartum cardiomyopathy (PPCMP) is a relatively rare form of dilated cardiomyopathy with unknown etiology. A generally accepted definition comprises the following criteria: 1) cardiac failure occurring in the last month of pregnancy or within 5 months after delivery; 2) absence of an alternative cause for the cardiomyopathy; 3) absence of heart disease before the last month of pregnancy and 4) demonstrated left ventricular dysfunction. From an intensivist's perspective, the diagnosis of PPCMP should always be considered when triaging a woman with peripartum respiratory or hemodynamic distress. Timely diagnosis is crucial to enable prompt initiation of the proper management in order to minimize the risk for serious maternal and neonatal sequelae. Goal-directed echocardiography should be utilized as early as possible, preferably already in the emergency department, to demonstrate or rule out PPCMP. Only then, appropriate supportive measures such as appropriate medical therapy, intra-aortic balloon counter pulsation (IABP), extracorporeal membrane oxygenation (ECMO) or assist device support can be initiated.

This paper reviews the current concepts and outlines appropriate management of conditions such as epilepsy, headache, benign intracranial hypertension, myasthenia gravis, multiple sclerosis, Bell's palsy and cerebrovascular disorders. It also discusses briefly, labor analgesia and anaesthesia in women with neurological disorders.