دانلود کتاب مراقبت های ویژه مامایی

The successful epidemiologic evaluation of any disease or condition has several prerequisites. Two of the most important prerequisites are that the condition should be accurately defined and that there should be measurable outcomes of interest. Another requirement is that there must be some systematic way of data collection or surveillance that will allow the measurement of the outcomes of interest and associated risk factors. The epidemiologic evaluation of critical illness associated with pregnancy has met with mixed success on all of these counts. Historically, surveillance of pregnancy-related critical illness has focused on the well-defined outcome of maternal mortality in order to identify illnesses or conditions that might have led to maternal death. Identification of various conditions associated with maternal mortality initially came from observations by astute clinicians. One of the best examples is the link described by Semmelweis between handwashing habits and puerperal fever. In most industrial and many developing countries, there are now population-based surveillance mechanisms in place to track maternal mortality. These are often mandated by law. In fact, the World Health Organization uses maternal mortality as one of the measures of the health of a population. Fortunately, in most industrialized nations, the maternal mortality rates have fallen to very low levels. Unfortunately, recent statistics for the United States suggest that overall maternal mortality has been increasing, but it remains unclear whether this is just due to improvements in surveillance. Although maternal mortality is an important maternal health measure, tracking maternal deaths may not be the best way to assess pregnancy- related critical illnesses since the majority of such illnesses do not result in maternal death. As stated by Harmer, “death represents the tip of the morbidity iceberg, the size of which is unknown.” Unlike mortality, which is an unequivocal endpoint, critical illness in pregnancy as a morbidity outcome is difficult to define and, therefore, difficult to measure and study precisely. There are many common conditions in pregnancy– such as hypertensive diseases, intrapartum and postpartum hemorrhage, venous thromboembolism, diabetes, thyroid disease, asthma, seizure disorders, and infection and sepsis– that occur frequently and require special medical care, but do not actually become critical illnesses. Most women with these complications have relatively uneventful pregnancies that result in good outcomes for both mother and infant, but each of these conditions can be associated with significant complications that have thepotential for serious morbidity, disability, or death. The stage at which any condition becomes severe enough to beclassified as a critical illness has not been clearly defined. However, it may be helpful to consider critical illness as impending, developing, or established significant organ dysfunction, which may lead to long-term morbidity or death. This allows some flexibility in the characterization of disease severity, since it recognizes conditions that can deteriorate rather quickly in pregnancy.