CLINICAL CASE
Unit Two: Obstetrics
Section B: Abnormal Obstetrics
Objective 28: Postpartum Infection
Patient 1
A 19-year-old G1 now P1 African-American, two day post op from a c-section is
evaluated for a fever of 39o C. She denies nausea or vomiting, but has noticed
increased lower abdominal pain since last evening. Her pregnancy was uneventful and
she presented to the hospital at 38 6/7 days with rupture of membranes. 12 hours
later, she is given Pitocin to induce labor. 9 hours later, she is 5 cm/completely
effaced and vertex at zero station. Despite adequate contractions (240 Montevideo
units per hour), she has had no progress for 3 hours. At this time, a primary low
transverse cesarean section is performed. She delivered a viable male, 3750 grams,
with Apgar 9/9 at one and five minutes respectively. At the time of birth, she is given
Keflex 1 gm for intrapartum prophylaxis.
Past Medical History
Med: neg
Surgeries: none
No known drug allergies
Medications: Prenatal vitamins, Iron, Folate
Lab
WBC: 16.9 w/ 70% PMNs
Hematocrit: 34 vol. %
UA: negative
Patient 2
You are part of the obstetrical team caring for a 32-year-old primipara who has
presented with a term pregnancy and spontaneous rupture of membranes. The fluid
is clear, the baby is active and has a heart rate of 125, with good reactivity and
variability. The patient has had an unremarkable prenatal course. Pitocin induction
is begun 24 hours after SROM.
Ten hours after beginning Pitocin induction, the patient is noted to be doing well
with her epidural. Her cervix is 7 cm dilated, 100% effaced. The fetus is in the vertex
position, seemingly OP, at -2 station. Her exam is unchanged 2 hours later despite Q
3 min. contractions that measure 60 mm Hg by an internal pressure catheter. She is
advised to have a cesarean section.
She delivers a 9 1b. 2 oz. boy, Apgars 7 and 9, by low transverse cesarean section.
The procedure is uncomplicated. Blood loss is estimated at 500 cc. She receives 2
grams of a cephalosporin for prophylaxis after the umbilical cord is clamped and 20
units of Pitocin after the placenta is removed.
On the second full day postpartum/post op, she complains of generally not feeling
well. She feels tired and achy, and wonders if she has a fever. She has no appetite and
has not yet passed flatus. The nurse reports that the patient’s pulse is 88, BP 110/70,
and temperature 38.5 °C. Lower abdominal and uterine tenderness are the only
positive findings on exam.
Lab
19,000 WBC, Hct 34, VA few epithelial cells, 1-5 WBC’s, rare bacteria
Assessment/Plan
Postpartum endometritis
Parenteral antibiotics
Discussion
Postpartum endometritis remains a common and potentially serious complication of
abdominal delivery. This infection is also termed endometritis, metritis,
endomyometritis and endomyoparametritis. Of these, endometritis is the most
commonly used term to describe postpartum uterine infection.
The route of delivery that is vaginal vs. cesarean section is the single most important
risk factors. The incidence of endometritis following vaginal delivery rarely exceeds 2
– 3%; however, after cesarean section frequency ranges from 10% in low risk patients
who have received prophylactic antibiotics to as high as 95% in a high risk population
without prophylactic antibiotics. In the later group, i.e. cesarean section, if the
membranes have been ruptured for a prolonged period of time (> than 6 hours) and
the patient has had prolonged labor, then the likelihood of endometritis is markedly
increased. There are few data to support a direct increase in endometritis following
the use of electronic fetal monitoring or on the number of vaginal examinations. It is
true and related that with slow progress of labor there are more vaginal exams
performed.
It is well established that the pathogenesis of postpartum endometritis involves both
anaerobic and aerobic organisms. This infection is an ascending infection and is
caused by the organisms found in the normal vaginal flora. These included the aerobic
organisms of Group A and B Streptococcus, Enterococcus, as well as Staphylococcus,
Gram-negative aerobic organisms include E.coli, Klebsiella pneumoniae, and Proteus
mirabilis, as well as a whole host of anaerobic organisms. The precise pathogenesis is a
complex interaction among the host defense mechanisms, the size of bacterial
inoculum and virulence of the bacteria involved. Obviously, the number of bacteria
and the size of the inoculum are primarily influenced by the length since rupture of
the membranes, the duration of labor, as well as, potentially, the number of vaginal
examinations.
The most common reported clinical signs and symptoms of postpartum endometritis
include fever, leukocytosis, lower abdominal pain, uterine tenderness and foulsmelling vaginal discharge. Clearly, the most important sign and symptom is that of
fever. This diagnosis is based on clinical findings alone and there has been no
laboratory and/or culture techniques used to increase the likelihood of this diagnosis.
At the time diagnosis of endometritis, parenteral antibiotic therapy is begun. Single
agent therapy, such as broad spectrum second and third-general cephalosporins offer
the advantage of less toxicity and theoretically less pharmacy and nursing time for
administration. When compared to the gold standard of clindamycin-gentamicin, the
cure rates and efficacy rates are identical. Failure to respond to the antibiotic therapy
within 48-72 hours may be due to pelvic abscess, septic pelvic thrombophlebitis
and/or the emergence of a resistant organism. The treatment should be continued
until the patient is afebrile, as well as asymptomatic, for 24-36 hours. Patient may be
discharged from the hospital at this time with no antibiotic therapy, as follow up oral
antibiotics are generally unnecessary.
Teaching points
1.
Postpartum infection is common especially in high-risk groups (preterm
delivery, prolonged ruptured membranes, prolonged labor, women
whose delivery via cesarean section).
2.
This is an ascending polymicrobial infection involving both grampositive anaerobes and gram-negative anaerobes.
3.
Prophylactic administration of antibodies will decrease the likelihood of
endometritis after a cesarean section by > 50%.
4.
Sequelae of endometritis include pelvic abscess, septic pelvic vein
thrombophlebitis or phlegmon.
5.
Treatment should include broad-spectrum coverage for the
polymicrobial organisms most commonly involved in endometritis.