Although mortality outcomes are similar, conservative rather than liberal fluid management is associated with fewer days of mechanical ventilation (Wiedemann, 2006). Some pregnancyinduced physiological changes predispose to a greater risk of permeability edema from vigorous fluid therapy. Colloid oncotic pressure (COP) is determined by serum albumin concentration, and 1 gl dL exerts approximately 6 mm Hg pressure. As discussed in Chapter 4 (p. 68), serum albumin concentrations normally drop in pregnancy. This results in a decline in oncotic pressure from 28 mm Hg in the nonpregnant woman to 23 mm Hg at term and to 17 mm Hg in the puerperium (Benedetti, 1979; Dennis, 2012). With preeclampsia, endothelial activation with leakage causes extravascular albumin loss and lowered serum albumin levels. As a result in these cases, 14 mm Hg postpartum (Zinaman, 1985). hese changes have a significant clinical efect on the colloid oncotic pressure/wedge pressure gradient. Normally, this gradient exceeds 8 mm Hg. However, when it is 4 mm Hg or less, the risk for pulmonary edema rises. No benefits are gained by albumin rather than crystalloid infusions in these women (Uhlig, 2014). hese associations were reviewed by Dennis and Solnordal (2012).
No long-term follow-up studies address gravidas who recover from ARDS. In nonpregnant subjects, risks for impaired global cognitive function at 3 and 12 months are significant (Pandharipande, 2013). Data from nonpregnant patients indicate a 1-to 2-year hiatus before basic normal activity is restored in all. In a 5-year follow-up study, Herridge and associates (201r1) reported normal lung function but signiicant exercise limitation, physical and psychological sequelae, decreased physical quality of life, and increased use of health-care services.
This syndrome is induced by a systemic inlammatory response to bacteria or viruses or their by-products such as endotoxins or exotoxins. The severity of the syndrome is a continuum or spectrum 47-3). According to the Centers for Disease Control and Prevention (CDC), sepsis caused 6.2 percent of pregnancy-related deaths in the United States from 201r1 to 2013 (Creanga, 2017). It was also a signiicant cause of maternal mortality in Michigan and the United Kingdom (Bauer, 2015; 110hamed-Ahmed, 2015; Nair, 2015).
Infections that most commonly cause sepsis syndrome in obstetrics are pyelonephritis (Chap. 53, p. 1028), chorioamnionitis and puerperal sepsis (Chap. 37, p. 667), septic abortion (Chap. 18, p. 351), and necrotizing fasciitis (Chap. 37, p. 671). With severe sepsis, the mortality rate in nonpregnant patients is 20 to 35 percent and is 40 to 60 percent with septic shock (Angus, 2013; Munford, 2015). With shock, the mortality rate in pregnancy has been reported to be 30 percent (Mabie, 1997; Snyder, 2013). That said, the maternal mortality risk from sepsis is significantly underestimated (Bauer, 2015; Chebbo, 2016; Mohamed-Ahmed,r2015).