Fetal, Preterm, and Term Neonate Exposure to Remifentanil: A Systematic Review of Efficacy and Safety

Antibiotics, Analgesic Sedatives, and Antiseizure Medications Frequently Used in Critically Ill Neonates: A Narrative Review

Antibiotic, analgesic sedative, and antiseizure medications are among the most commonly used medications in preterm/sick neonates, who are at high risk of nosocomial infections, central nervous system complications, and are exposed to numerous painful/stressful procedures. These severe and potentially life-threatening complications may have serious short- and long-term consequences and should be prevented and/or promptly treated. The reported variability in the medications used in neonates indicates the lack of adequate neonatal studies regarding their effectiveness and safety. Important obstacles contributing to inadequate studies in preterm/sick infants include difficulties in obtaining parental consent, physicians' unwillingness to recruit preterm infants, the off-label use of many medications in neonates, and other scientific and ethical concerns. This review is an update on the use of antimicrobials (antifungals), analgesics (sedatives), and antiseizure medications in neonates, focusing on current evidence or knowledge gaps regarding their pharmacokinetics, indications, safety, dosage, and evidence-based guidelines for their optimal use in neonates. We also address the effects of early antibiotic use on the intestinal microbiome and its association with long-term immune-related diseases, obesity, and neurodevelopment (ND). Recommendations for empirical treatment and the emergence of pathogen resistance to antimicrobials and antifungals are also presented. Finally, future perspectives on the prevention, modification, or reversal of antibiotic resistance are discussed.

Determination of remifentanil in neonatal dried blood spots by liquid chromatography-tandem mass spectrometry

Remifentanil is an ultra-short-acting synthetic opioid-class analgesic which might be increasingly used "off-label" as pain management during labour. Side effects in parturients during labour, and in the infant at birth are of particular concern, especially respiratory depression which is concentration-dependent, and can occur at levels as low as 3-5 ng mL-1. The safety of such use, particularly in newborns due to remifentanil placental transfer, has not been fully demonstrated yet, partly due to the lack of a suitable non-invasive analytical method. The aim of our work was to develop a sensitive method to monitor the levels of remifentanil in neonates by a non-invasive sampling of umbi lical cord blood to support efficacy and safety trials. The presented LC-MS method is sensitive enough to reliably quantify remifentanil in just 20 µL of blood at only 0.3 ng mL-1. The dried blood spot sample preparation included solvent extraction with subsequent solid-phase extraction. The method was validated in terms of accuracy, precision, recovery, matrix effect, and stability, and was successfully applied to a small pilot study. The estimated arterial blood concentrations at the time of delivery ranged from 0.2 to 0.3, and up to 0.9 ng mL-1 in neonatal, and maternal samples, respectively.

Neonatal Outcomes in Labor After Intravenous Remifentanil Analgesia vs. Epidural Analgesia: A Retrospective Observational Study

Background Some evidence indicates that maternal analgesia during labor may have adverse effects on neonates due to exposure to specific drugs or the potential effects of analgesia on the course of labor. We assessed the clinical outcome of term neonates born to mothers who received epidural analgesia (E) or systemic analgesia with remifentanil (R) during labor. Methods Data was collected retrospectively over one year. We have evaluated the medical records of 247 full-term neonates; 208 were born to mothers who received E and 39 to mothers who received R. Data on Apgar scores and neonatal complications (perinatal asphyxia, respiratory distress, infection, hyperbilirubinemia, and birth injuries), and average hospital stay were collected. Mann-Whitney U test, chi-square test, and logistic regression analysis were used where appropriate. Results The values of the mean Apgar scores between E and R at 1 and 5 minutes were similar (8.83 vs. 8.97, p = 0.252; 9.81 vs. 9.87, p = 0.762, respectively). The average length of neonatal hospitalization did not differ between groups (4.19 vs. 4; p = 0.557). The percentages of neonates with any complication were similar between groups (28.3% vs. 32.5%, p = 0.598). Neonates born by cesarean delivery (CD) had significantly worse outcomes than those born vaginally (p = 0.008, OR 2.8, 95% CI [1.30, 6.17]). Conclusion We did not find a statistically significant difference in mean Apgar scores and neonatal complications between neonates who received epidural vs. remifentanil analgesia. An increased rate of complications in neonates born via CD was found. Future studies should have a larger sample size and be powered to detect associations in these findings.

Factors influencing the use of epidural labor analgesia: a cross-sectional survey analysis

Introduction

This study aimed to explore the personal and organizational factors influencing the lack of implementation of epidural labor analgesia (ELA).

Methods

This study was conducted at the Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China. A total of 451 women who underwent vaginal delivery without ELA between 8 October 2021 and 30 March 2022, were included. A questionnaire was used to collect the relevant data. We derived and validated the variable, without ELA, by using binary logistic regression analysis.

Results

Of the total 451 included, 355 (78.7%) initially preferred ELA, whereas 96 (21.3%) rejected it directly. Five variables were validated (p < 0.05): multiparas, ELA would lead to back pain, experienced ELA in previous delivery, the inner attitude toward labor pain, and blood routine and coagulation function not being tested within 14 days. The sensitivity and specificity of this model were 96.3 and 69.8%, respectively.

Conclusion

The corresponding training should be provided to the medical staff to identify women at high risk of rejecting ELA during the prenatal examination process using a questionnaire, then provide them with knowledge regarding ELA, so that ELA can benefit more mothers. Additionally, the existing organizational factor should be addressed in order to efficiently provide ELA services to mothers.

Clinical trial registration

This study was registered at the Chinese Clinical Trial Registry (Chi CTR 2000034625) on July 12, 2020.

Low-Dose Remifentanil in Preterm Cesarean Section with General Anesthesia: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVE

The conventional technique of general anesthesia induction during a Cesarean section involves the use of opioids only after cord clamping. We hypothesized that the use of remifentanil before cord clamping might reduce the use of maternal supplemental anesthetic agents and improve the maternal hemodynamics status and neonatal adaptation of the preterm neonate.

METHODS

A phase III, double-blind, randomized, placebo-controlled, hospital-based trial enrolled parturients undergoing a Cesarean section under general anesthesia before 37 weeks of gestation. Block randomization allocated pregnant women to remifentanil or placebo. The primary outcome was the rate of newborns with Apgar scores < 7 at 5 min. Secondary outcomes were maternal hemodynamic parameters, complications of anesthetic induction, use of adjuvant anesthetic agents, neonatal respiratory distress, umbilical cord pH, and lactate levels.

RESULTS

A total of 52/55 participants were analyzed, comprising 27 women in the remifentanil group and 25 in the placebo group. Nine of 27 (33.3%) neonates had an Apgar score < 7 at 5 min in the remifentanil group versus 11/25 (44.0%) in the placebo group (p = 0.45, odds ratio = 0.66, 95 confidence interval 0.20-2.18). The blood cord gases, cognitive, behavior, sensory, sleeping, and feeding scores at 1 and 2 years of corrected age were not different. For the mothers, hemodynamic parameters, anesthesia duration, and the cumulative treatment dose until cord clamping did not differ between the groups.

CONCLUSIONS

The use of a low dose of remifentanil before cord clamping for a Cesarean section appears to be safe both for the mother and the preterm newborn, but it does not improve maternal or neonatal outcomes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT02029898.