Short summary

Objective:
To assess the timing of prophylactic antibiotics for caesarean section in relation to the rate of surgical site infections and to assess the possible impact of antibiotic on infant microbiota.

Design:
An unblinded parallel randomised controlled feasibility trial.

Setting:
Odense University Hospital, Denmark.

Population:
Women (BMI<30) scheduled for planned caesarean section and their infants.

Methods:
Women are randomly assigned into two groups receiving prophylactic antibiotic administrated either 15 to 60 minutes before skin incision or after umbilical cord clamping. Blood and stool samples are collected from the infants. Follow-up are 30 days + 9 months.

Main outcome measure:

1. Infant gut microbiota at the 10th day of life and follow-up at 9 months
2. Cefuroxime clearance among newborn infants if the mother received antibiotic prior to cord clamping.

Rationale

Women undergoing a caesarean section (CS) have a relatively high risk of postpartum infections. Usually, surgical antibiotic prophylaxis is given before skin incision to reduce the risk of wound infection.  The effect of prophylactic antibiotic is optimal if the dose is administrated within one hour before the surgical incision, and the risk may even be further reduced if antibiotic is administrated within 30 minutes before incision. For caesarean section antibiotics is often given after birth to reduce the antibiotic exposure of the infant. As wound infection after caesarean section remains a clinically important problem, it is relevant to explore the relevance of this special precaution.

Description of the cohort

Eligible participants are women, age 18 or older, with a pre-gestational BMI < 30, reading and understanding Danish, who give birth by planned CS at Odense University Hospital.

Data and biological material

Infants were the mother was exposed to pre-incisional antibiotic: blood sample from the umbilical cord and two blood samples from the infant 3-4 hours and 8-10 hours after delivery. All infants in both groups: a blood sample taken on the 2nd-3rd days postpartum for immunological analyses. The parents collect stool samples on day 10 and 9 months postpartum.

The parents answer a nutritional questionnaire from birth through to the 10th day postpartum. Information about symptoms of infection, contacts with the healthcare system, and the need for antibiotics after discharge was obtained by a questionnaire sent electronically to all participants (the mothers) within 30 days post-CS.

Collaborating researchers and departments

Department of Plastic Surgery and Department of Gynaecology and Obstetrics, Odense University Hospital

• PhD-student Nana Hyldig

Department of Gynaecology and Obstetrics, Odense University Hospital

• Professor Jan Stener Jørgensen

Hans Christian Andersen Children's Hospital, Odense University Hospital

• Gitte Zachariassen, MD, PhD

The Danish Strategic Research Council project NEOMUNE

Publications associated with the project

The half-life and exposure of cefuroxime varied in newborn infants after a Caesarean section. Gitte Zachariassen, Nana Hyldig, Jan Stener Jørgensen, Dennis S Nielsen, Gorm Greisen. Acta Paediatr. 2016 Sep;105(9):1074-8