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CHAPTER 127: Critical Illness in Pregnancy 1261

in any postpartum patient with severe or quickly evolving sepsis that is variation is useful in the assessment of fluid-responsiveness early in
otherwise unexplained. Streptococcal toxic shock syndrome may occa- pregnancy, but may perform poorly later in pregnancy due to abdomi-
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sionally follow an uncomplicated pregnancy and delivery. 3 nal obstruction from the gravid uterus. Bedside echocardiography is
Septic abortion refers to abortion-associated endometritis, which commonly employed in the assessment of circulating volume; dynamic
can evolve to myometrial and perimetrial involvement and lead to collapse of the inferior vena cava (IVC) suggests a fluid responsive state.
life-threatening sepsis. Illegal abortions often employ rigid, non-sterile It is important to recognize that none of the indicators of hemody-
devices for uterine evacuation, which can cause uterine infection, namic fluid responsiveness have been tested rigorously in the pregnant
uterine perforation with peritonitis, and retention of products of con- patient. 82,83 Importantly, the gravid uterus may alter IVC filling, inde-
ception. 74,75 Patients present with fever, pelvic pain, and tenderness to pendent of the status of the circulating volume, and relief of aortocaval
palpation; peritoneal signs may be present. Thorough pelvic and abdom- compression through patient positioning will often enhance ultrasound
inal examinations, and ultrasound evaluation for retained products of assessment of cardiac function and vascular filling. Vasoactive agents are
conception are essential. indicated for hypotension refractory to volume resuscitation. When sep-
Chorioamnionitis complicates up to 4% of pregnancies. When treated sis is complicated by cardiac dysfunction, inotropic support with dobu-
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early and appropriately, sepsis is an uncommon complication. Patients tamine is recommended; as with nonpregnant patients, elevated cardiac
https://kat.cr/user/tahir99/illary return of
typically present with fever; maternal or fetal tachycardia, abdominal ten- filling pressures, a narrow pulse pressure, sluggish cap
derness, and foul-smelling amniotic fluid also may be present. However, the nailbed, and cool, clammy extremities suggest cardiac dysfunction.
the obstetric examination may be unrevealing, and chorioamnionitis The course of fluid resuscitation is guided by the clinical status; when
should be considered in patients with unexplained sepsis or ARDS. patients are volume replete and hemodynamically stable, transition to a
In pregnant patients, abdominal and pelvic wound infections typi- conservative fluid strategy is often warranted. A more detailed approach
cally result from the introduction of bacteria during cesarean section to hemodynamic resuscitation in sepsis is presented in Chap. 31. It is
or episiotomy procedures. Wound infections may present up to several worth noting that a central venous oxygen saturation (Scv O 2 ) lower than
weeks after delivery. While a variety of infectious agents can cause 70%, which often indicates inadequate oxygen delivery in nonpregnant
postpartum fever and mild wound infections, severe postpartum wound patients with sepsis, can be a normal finding in late pregnancy. 84
infections are most commonly due to group A Streptococcus (GAS). A Blood, urine, and pelvic sites should be cultured, and a chest x-ray
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small subset of GAS infections are caused by toxin producing or invasive obtained in the initial evaluation of sepsis. Empiric antibiotics should
strains, which are associated with substantial morbidity and mortality. provide polymicrobial coverage, including anaerobic coverage in the
In particular, invasive strains can cause necrotizing fasciitis or seed to case of a confirmed or suspected obstetric source. For those at risk of
distant sites. Surgical debridement can be lifesaving for severe wound nosocomial or resistant microbes, the regimen should be expanded as
infections, and prompt surgical evaluation is a critical part of the evalu- indicated. Coverage for methicillin resistant Staphylococcus aureus
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ation of postpartum sepsis. 3,72,77,78 (MRSA), most often due to a community acquired strain in pregnant
Nonobstetric infections also may cause maternal sepsis. The inci- patients, should be considered in those with severe skin or soft tissue
dence of pyelonephritis and the morbidity of pneumonia are both infections. Aminoglycosides may cause fetal toxicity, and if possible are
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increased in pregnancy. While bacteriuria or asymptomatic bacteremia avoided antepartum. Even if a single microbe is isolated in blood cultures,
is common, only a minority of pregnant patients develop frank pyelone- polymicrobial coverage should be continued in unstable patients with
phritis and sepsis, usually later in pregnancy when ureteral stasis is most pelvic infections, where blood cultures have been described as the “tip of
pronounced. Gram-negative rods are the most common cause of pyelo- the iceberg” of local microbial burden. Source control is critical, and a
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nephritis, although the prevalence of gram positive microbes increases thorough pelvic evaluation is mandatory. Retained products of concep-
as pregnancy progresses. Pneumonia in pregnancy is reviewed below. tion require immediate evacuation. In septic patients receiving adequate
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Other infections are less common, but can be severe. Pregnancy is asso- empiric antibiotics, ongoing deterioration can be suggestive of a localized
ciated with a substantially increased risk of listeriosis, which presents abscess, a resistant organism, or septic thrombophlebitis. Surgical drain-
3
with fever and flu-like symptoms. Maternal illness is usually mild, but age, with possible hysterectomy, may be required, particularly in patients
serious CNS infection can occur, and the accompanying fetal illness is with myometrial microabscesses or gas gangrene from clostridial species.
usually severe. The risk of disseminated herpes virus is also increased Computed tomography or magnetic resonance imaging of the pelvis may
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in pregnancy. Globally, malaria and viral hepatitis are also important aid in the diagnosis of septic pelvic thrombophlebitis, which requires
causes of sepsis in pregnancy. Finally, while cholecystitis and appen- anticoagulation in addition to antibiotics; rarely venous ligation or surgi-
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dicitis are not more common in pregnancy, their clinical presentations cal excision may be required as well. Sepsis from chorioamnionitis is
3
may be altered by the effect of the gravid uterus on the abdominal exam. unlikely to respond to antibiotic therapy alone, and delivery of the fetus
3
Management: As part of expectant management, obstetric, critical care is usually indicated. When chorioamnionitis is suspected, diagnostic
and anesthesiology staff should be apprised early of a deteriorating preg- sampling of amniotic fluid may aid in the decision for delivery.
nant patient. Achieving quick hemodynamic stability is a cornerstone of In addition to supporting hemodynamics and treating infection, several
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sepsis management, and is particularly important in pregnancy where other measures contribute to the successful management of sepsis. If
blood flow is a key determinant of fetal oxygen delivery. Antimicrobial indicated, mechanical ventilation should be instituted expeditiously; strat-
therapy and source control are essential, and should occur in parallel egies for ARDS are reviewed below. Fevers are detrimental to the fetus, and
with hemodynamic management. are treated with acetaminophen and cooling blankets. As cortisol is often
The hypoperfusion of sepsis can be multifactorial, and assessing elevated in pregnancy, the corticotropin stimulation test may be difficult
preload, afterload, and contractility is imperative. While the circulating to interpret; if adrenal insufficiency is suspected on clinical grounds, corti-
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volume is nearly always inadequate and requires aggressive management costeroids may be given in refractory shock. Glucose control is indicated
in the early phase of sepsis, refractory vasodilation or impaired contrac- as it is for nonpregnant patients. Renal replacement may be required if
tility often contribute to ongoing hypoperfusion and shock. In normal renal failure develops. Finally, providing nutritional support, avoiding
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pregnancy, the central venous pressure (CVP) is generally unchanged oversedation, and preventing venous thromboembolic disease, gastroin-
from prepregnancy levels; if there are no impediments to venous return testinal ulcers, and secondary infections are important.
and be useful in guiding resuscitation. In the setting of valvular disease, ■ PREECLAMPSIA
or forward flow, the CVP should accurately reflect circulating volume
heart failure, pericardial disease, or other conditions of obstruction, the Preeclampsia is a unique disorder of pregnancy, marked by endothelial
CVP reflects right-sided pressures but is less reliable in gauging the cir- dysfunction, hypertension, and proteinuria. It occurs in 2% to 8% of
culating volume and in predicting fluid-responsiveness. Pulse pressure pregnancies, and is a significant cause of obstetric ICU admissions and

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