Neonatal Sepsis (Sepsis Neonatorum)
Medical Author: John Mersch, MD, FAAP
Medical Editor: William C. Shiel Jr., MD, FACP, FACR
Neonatal sepsis is any infection involving an infant during the first 28 days
of life. Neonatal sepsis is also known as "sepsis neonatorum." The infection may
involve the infant globally or may be limited to just one organ (such as the
lungs with pneumonia). It may be acquired prior to birth (intrauterine sepsis)
or after birth (extrauterine sepsis). Viral (such as herpes, rubella [German
measles]), bacterial (such as group B strep) and more rarely fungal (such as
Candida) causes may be implicated.
During her pregnancy, a women's obstetrician is constantly monitoring the
health of both of the pregnant women and her fetus for any signs or symptoms
that might indicate sepsis. Prior to birth, many indicators can signal that a
potential infection is developing. Women are screened for infectious diseases at
their first OB office visit. Some of these include HIV, gonorrhea, syphilis,
herpes, Chlamydia, and hepatitis B, as well as immunity to rubella
and chickenpox. Between the 35th and 37th week of pregnancy, screening for
group B strep is commonly performed. Some symptoms and signs, such as slower
than anticipated fetal growth, may be subtle indications of threatened fetal
well-being. Measurement of uterine size via the traditional tape measure or
ultrasound examination of the uterus, placenta, and fetus will both provide
critical information. Throughout the pregnancy, office visits provide the
opportunity to monitor fetal heart rate. The obstetrician commonly evaluates
both the actual heart rate at rest as well as the infant's cardiac response to a
mild stress (for example, uterine contraction). If concerns develop, specialized
evaluations can be performed ("stress testing") during which fetal heart rate,
fetal movement and fetal tone are monitored and an objective risk assessment may
be made. Maternal fever during her pregnancy warrants a timely and thorough
evaluation. Equally significant would be the onset of premature labor or
premature rupture of the amniotic sac (termed "premature rupture of membranes").
During labor, several indicators may raise concern regarding the possibility
of neonatal sepsis. Abnormalities of fetal heart rate, maternal fever, premature
separation of the placenta from the uterine wall, or foul smelling/cloudy
amniotic fluid all indicate a high-risk labor and delivery. These situations
will commonly prompt consultation with the pediatrician or neonatologist
regarding the potential for delivery and/or postpartum complications.
Any infant who fails to make a smooth transition from intrauterine to
extrauterine life should be considered at high risk for sepsis. Close monitoring
of vital signs (heart rate, respiratory rate and effort, skin color, temperature,
and "vigor") is a crucial part of the evaluation of the newborn. Infants may
manifest neonatal sepsis by subtle signs such as poor feeding, jaundice, unusual
rashes, or more obvious indicators such as seizures, projectile vomiting, or
abdominal distention. The importance of the clinical observations of the postpartum nurse cannot be understated.