Maternal oxygen transport variables during the third trimester of normal pregnancy

Recognition and Management of Sepsis in the Obstetric Patient

Sepsis is one of the principal causes of maternal mortality in obstetrics. Physiologic changes that occur during pregnancy create a vulnerable environment, predisposing pregnant patients to the development of sepsis. Furthermore, these changes can mask sepsis indicators normally seen in the nonobstetric population, making it difficult to recognize and treat sepsis in a timely manner. The use of maternal-specific early warning tools for sepsis identification and knowledge of appropriate interventions and their effects on the mother and fetus can help clinicians obtain the best patient outcomes in acute care settings. This article outlines the signs and symptoms of sepsis in obstetric patients and discusses treatment options used in critical care settings.

Severe sepsis during pregnancy

Severe sepsis is a major cause of mortality among critically ill patients. Early recognition accompanied by early initiation of broad-spectrum antibiotics with source control and fluid resuscitation improves outcomes. Hemodynamic resuscitation starts with fluid therapy followed by vasopressors if necessary. Cases refractory to first-line vasopressors (norepinephrine) will require second-line vasopressors (epinephrine or vasopressin) and low-dose steroid therapy. Resuscitation goals should include optimization of central venous oxygenation and serum lactate.

Pulmonary vasodilators--treating the right ventricle

Pulmonary hypertension remains a significant complication of several systemic and cardiothoracic diseases. It is important to emphasize that the hemodynamic relevance relates to the effect of pulmonary hypertension on right ventricular function and right-left ventricular interaction. The goal of pulmonary vasodilation should focus on optimizing right ventricular function and improving systemic perfusion. The properties of an optimum vasodilator include selective pulmonary vasodilation (avoiding systemic vasodilation), rapid onset of action, short half-life, and ease of administration. Inhaled nitric oxide or nebulization of traditional systemically administered agents offers the greatest clinical promise. An additional merit of selective pulmonary vasodilation consists of augmenting oxygenation by improving ventilation perfusion matching.

The management of respiratory infections during pregnancy

Respiratory infections that complicate pregnancy are encountered frequently, and they encompass a broad range of disorders. Although respiratory infections usually are not seen more commonly in pregnancy, they often result in greater morbidity and mortality secondary to the physiologic adaptations that occur during pregnancy. Pregnant patients who have one of these disorders require higher level of surveillance and intervention.

Cardiac disease and pregnancy

The pregnant state imposes a supraphysiologic strain on the pregnant woman's cardiac performance through complex biochemical, electric, and physiologic changes affecting the blood volume, myocardial contractility, and resistance of the vascular bed. In the presence of underlying heart disease, these changes can compromise the woman's hemodynamic balance, her life, and that of her unborn child. Cardiac pathology represents a heterogeneous group of disorders, each with its own hemodynamic, genetic, obstetric, and social implications. Physicians caring for these women should actively address the issue of reproduction. Ideally, pregnancy should be planned to occur after optimization of cardiac performance by medical or surgical means. Once pregnancy is achieved, the concerted effort of a multidisciplinary team of obstetricians, cardiologists, anesthesiologists, nursing, social, and other services provides the best opportunity to carry the pregnancy to a successful outcome.