Prophylactic perioperative cefuroxime levels in plasma and adipose tissue at the time of caesarean section (C-LACE): a protocol for a pilot experimental, prospective study with non-probability sampling to determine interpatient variability

Background: The aim of the C-LACE study is to measure cefuroxime concentration in plasma and adipose tissue of non-obese and obese pregnant women undergoing caesarean section. Methods: This study plans to compare maternal cefuroxime concentrations (plasma and adipose tissue), at the time of skin incision and time of skin closure during a caesarean section from non-obese (body mass index BMI < 30 kg/m²) and obese (BMI ≥ 30 kg/m²) pregnant women. The incidence of post-surgical site infection will also be measured. At least 15 participants are required for each arm (non-obese vs obese) with a total of 30 participants. The study participants will be followed up between 30 and 40 days post-caesarean section to record details of any post-caesarean surgical infection to explore correlations between BMI, measured cefuroxime concentrations and post-caesarean infection rates. Discussion: This pilot study will allow the development of a model testing the inter-patient variability in plasma and adipose tissue concentrations of cefuroxime. The results will facilitate the development of a larger study to determine whether differences in cefuroxime plasma and tissue concentration in obese and non-obese women can support the development of a physiologically based pharmacokinetic model. This model can then be used to propose dosing adjustments that can be used in a further trial to optimise cefuroxime dosing for women undergoing caesarean section. Trial registration: ISRCTN Registry, ISRCTN17527512. Registered on 26 October 2020