Treatment of Chorioamnionitis After Delivery

Chorioamnionitis refers to infection of the amniotic fluid, membranes, placenta and/or
uterus. Clinical chorioamnionitis is defined by a temperature of 380 C or more and one or
more of the following findings: maternal heart rate > 100 BPM, baseline fetal heart rate >
160 BPM, uterine tenderness, or foul smelling amniotic fluid. It complicates 0.5 to 10.5
percent of deliveries and accounts for 10 to 40 percent of cases of maternal febrile
morbidity in the peripartum period and 50 percent of preterm deliveries before 30 weeks of
gestation. Chorioamnionitis is also associated with 20 to 40 percent of cases of early
neonatal sepsis and pneumonia. (Hagberg et al). The most extensively tested antibiotic
regimen is ampicillin 2 g IV every 6 hours and gentamicin 1.5mg/kg every 8 hours. After
delivery clindamycin 900 mg IV q 8 hours can be used for further coverage in those women
delivering by cesarean section. The treatment is usually continued until the patient is
asymptomatic for 24 - 48 hours although that treatment is primarily based on expert opinion.
(Edwards et al). Potential benefits of not needing to treat with antibiotics after a
delivery complicated by intramniotic infection is shortened hospital stay and reduced cost.
No studies up until now have compared treatment verses no treatment head to head for vaginal
delivery and one postpartum dose vs. continued treatment for 24 hours in the women
undergoing a cesarean delivery. Unfortunately the Duff study combined patients analyzing
both vaginal deliveries and cesarean deliveries together. They were both treated with either
the single dose of antibiotics or continual treatment with antibiotics until afebrile and
asymptomatic for 24 hours. He found no statistical significant difference in treatment
failure in the one dose vs. multiple dose groups. This finding was the primary outcome of
the study.Our study will be a double blind placebo controlled randomized study. There will
be two arms: vaginal delivery and cesarean delivery. The first arm consists of patients who
have had a vaginal delivery complicated by chorioamnionitis. They will be randomized into
one of two groups: 1) no further antibiotics after delivery ( they will receive a saline
infusion instead of antibiotics but this will be labeled in the pharmacy and neither the
patient nor the physician will know whether the patient is receiving antibiotics or saline)
or 2) one additional dose of antibiotics (ampicillin 2 grams IV, gentamicin 1.5 mg/kg IV)
following their vaginal delivery. The second arm of this study consists of patients who have
had a cesarean delivery complicated by chorioamnionitis. They will also be randomized into
one of two groups: 1) one dose of ampicillin 2 grams IV, gentamicin 1.5 mg/kg IV,
clindamycin 900 mg IV and then saline infusions instead of antibiotics until they are
afebrile for 24 hours ( they will receive saline infusions instead of antibiotics but this
will be labeled in the pharmacy and neither the patient or the physician will know whether
the patient is receiving antibiotics or saline) or 2) ampicillin 2 g IV every 6 hours,
gentamicin 1.5mg/kg every 8 hours, and clindamycin 900 mg IV every 8 hours until the patient
has been afebrile for 24 hours. For the patients in both arms of the study the primary
outcome will be treatment failure defined as either a single temperature of 39 C or two or
more temperatures of 38.4 C or more at least 4 hours apart after delivery in the vaginal
group or after the first antibiotic dose in the cesarean group. All treatment failures will
be treated with ampicillin 2 grams IV every 6 hours, gentamicin 1.5 mg/kg every 8 hours and
clindamycin 900 mg every 8 hours until the patient has been afebrile and asymptomatic for 24
hours. Timing of temperature spikes or other symptoms associated with uterine infection will
be noted as well as number of doses of antibiotics and infection related complications such
as wound infection, pelvic abscess and septic pelvic thrombophlebitis. Patients will be
recruited from the Labor and Delivery unit here at Naval Medical Center Portsmouth. All
patients that develop chorioamnionitis will be offered participation in the study. All women
greater than 18 years old will be eligible to participate. Patients will be consented by the
residents and staff working on labor and delivery. Exclusion criteria will include those who
do not wish to participate, patients who are allergic to the study antibiotics, women who
are immunocompromised or women receiving antibiotics for other reasons such as prophylaxis
for bacterial endocarditis.

Inclusion Criteria:.

- All patients that develop chorioamnionitis and who are over 18 years of age will be
offered participation in the study.

Exclusion Criteria:

- Women who do not wish to participate, patients who are allergic to the study
antibiotics

- Women who are immunocompromised or women receiving antibiotics for other reasons such
as prophylaxis for bacterial endocarditis