Optimal administration of cefazolin prophylaxis for cesarean delivery

Surgical-site infection in multifetal cesarean delivery

PURPOSE

The relationship between multifetal cesarean delivery and surgical-site infection (SSI) is unclear. If SSI is more common in multifetal cesareans, adjustment of practices such as antibiotic dosing could be warranted. The purpose of this study was to determine whether patients undergoing multifetal cesarean delivery are more likely to experience SSI than those undergoing singleton cesarean delivery.

METHODS

This was a retrospective cohort study including all cesarean deliveries at a tertiary hospital from 10/1/2009 to 12/28/2018. The primary outcome was rate of SSI in women after multifetal cesarean delivery as compared to those who underwent singleton cesarean delivery. Univariable analysis and multivariable logistic regression were used to assess independent clinical factors associated with SSI in multifetal cesarean deliveries.

RESULTS

34,340 women underwent cesarean delivery during this period. 33,211 were singletons (96.7%), and 1,129 were multifetal (3.3%). There was no difference in the rate of SSI in multifetal gestations (15/1,129, 1.3%) as compared to singletons (493/33,211, 1.5%) (p = 0.670, OR 0.89 [95% CI 0.53, 1.50], aOR 1.06 [95% CI 0.61, 1.84]). Limiting analysis to multifetal deliveries, prolonged rupture of membranes (p < 0.004, OR 5.43 [95% CI 1.49, 19.88]), labor augmentation (p < 0.001, OR 15.84 [1.74, 144.53]), and chorioamnionitis (p < 0.001, OR 15.43 [95% CI 3.11, 76.62]) were more common in women with SSI.

DISCUSSION

SSI is not increased in multifetal cesarean delivery as compared to singleton cesarean delivery. In multifetal cesareans, chorioamnionitis, prolonged rupture of membranes, and labor augmentation were associated with increased odds of SSI.

Understanding the pharmacokinetics of antibiotics in pregnancy: Is there a role for therapeutic drug monitoring? A narrative review

PURPOSE

Antibiotics are commonly used during pregnancy. However, physiological changes during pregnancy can affect the pharmacokinetics of drugs, including antibiotics, used during this period. Pharmacokinetic evaluations have shed light on how antibiotics are affected during pregnancy and have influenced dosing recommendations in this context. Methods: A narrative review was conducted and included reports providing data reflecting drug distribution and exposure in the context of pregnancy. Results: Pharmacokinetic parameters of antibiotics in pregnancy and transplacental passage of antibiotics are comprehensively presented. Conclusion: Knowledge about the impact on pharmacokinetics and fetal exposure is especially helpful for complicated or severe infections, including intra-amniotic infection and sepsis in pregnancy, where both mother and fetus are at risk. Further studies are warranted to consolidate the role of therapeutic drug monitoring in complicated or severe infections in pregnant patients.

Calculating the appropriate prophylactic dose of cefazolin in women undergoing cesarean delivery

BACKGROUND AND OBJECTIVES

Surgical site infection and other postoperative complications are relatively common in obstetrical procedures, and they are associated with morbidity, prolonged hospital stay, and readmissions. Appropriate levels of antimicrobial agents given directly before skin incision can prevent the establishment of surgical-related infection caused by endogenous microorganisms present on the woman's skin. We aimed to determine serum concentrations of cefazolin given to pregnant women prior to scheduled cesarean delivery and to compare their drug concentrations and pharmacokinetics in 2 weight groups.

STUDY DESIGN

We conducted a prospective cohort analysis of the pharmacokinetics of cefazolin in women undergoing cesarean delivery (August 2017 to September 2018). One or two grams of intravenous cefazolin was administered within 30 min prior to skin incision to women weighing <80 kg and ≥80 kg, respectively. Maternal serum samples were obtained at skin incision and 30 min later. The serum concentration of cefazolin was measured by high-pressure liquid chromatography. Antimicrobial coverage was defined as being appropriate when the cefazolin levels were above the minimal inhibitory concentration. Pharmacokinetic parameters were estimated using a one-compartment model.

RESULTS

A total of 61 women were enrolled, of whom 47 underwent cesarean delivery (study group). The mean time that had elapsed between drug administration to incision was 13 ± 6.9 min (95% confidence interval 10.6-16.2 min). The drug levels after 30 min in women who weighed >80 kg and in women who received 2 g cefazolin, after 30 min from incision differed significantly (87.0 ± 26.0 vs 55.4 ± 16.6 μg/ml, p = .0001).

CONCLUSION

A single 1- or 2-g dose of cefazolin provides serum concentrations above minimal inhibitory concentrations for susceptible pathogens in most women undergoing scheduled cesarean delivery.

Reducing post-caesarean delivery surgical site infections: a narrative review

Surgical site infection complicates 1-10% of caesarean deliveries. With the rate of caesarean delivery increasing, it is important to identify effective measures of preventing surgical site infection and to consider their impact on maternal and neonatal outcomes. Compelling evidence supports the use of prophylactic antibiotics, prior to skin incision, to reduce surgical site infection. However, there remain international variations in terms of the recommended agent, dose and body weight-adjusted dosing. Advances in wound dressings are an evolving area of interest and surgical technique can influence outcomes. This narrative review explores pharmacological and non-pharmacological methods of preventing surgical site infection following caesarean delivery.