Prenatal buprenorphine exposure: Effects on biochemical markers of hypoxia and early neonatal outcome

Buprenorphine use in pregnant opioid users: a critical review

Pregnancy in opioid users poses a number of problems to treating physicians. Most guidelines recommend maintenance treatment to manage opioid addiction in pregnancy, with methadone being the gold standard. More recently, buprenorphine has been discussed as an alternate medication. The use and efficacy of buprenorphine in pregnancy is still controversial. This article reviews the current database on the basis of a detailed and critical literature search performed in MEDLINE (206 counts). Most of the relevant studies (randomised clinical trials and one national cohort sample) were published in the last 2 years and mainly compared buprenorphine with methadone. Some studies are related to maternal outcomes, others to foetal, neonatal or older child outcomes. With respect to maternal outcomes, most studies suggest that buprenorphine has similar effects to methadone. Very few data from small studies discuss an effect of buprenorphine on neurodevelopment of the foetus. Neonatal abstinence syndrome is common in infants of both buprenorphine- and methadone-maintained mothers. As regards neonatal outcomes, buprenorphine has the same clinical outcome as methadone, although some newer studies suggest that it causes fewer withdrawal symptoms. Since hardly any studies have investigated the combination of buprenorphine with naloxone (which has been suggested to possibly have teratogenic effects) in pregnant women, a switch to buprenorphine monotherapy is recommended in women who become pregnant while receiving the combination product. These novel findings indicate that buprenorphine is emerging as a first-line treatment for pregnant opioid users.

Buprenorphine treatment of opioid-dependent pregnant women: a comprehensive review

AIMS

This paper reviews the published literature regarding outcomes following maternal treatment with buprenorphine in five areas: maternal efficacy, fetal effects, neonatal effects, effects on breast milk and longer-term developmental effects.

METHODS

Within each outcome area, findings are summarized first for the three randomized clinical trials and then for the 44 non-randomized studies (i.e. prospective studies, case reports and series and retrospective chart reviews), only 28 of which involve independent samples.

RESULTS

Results indicate that maternal treatment with buprenorphine has comparable efficacy to methadone, although difficulties may exist with current buprenorphine induction methods. The available fetal data suggest buprenorphine results in less physiological suppression of fetal heart rate and movements than methadone. Regarding neonatal effects, perhaps the single definitive conclusion is that prenatal buprenorphine treatment results in a clinically significant less severe neonatal abstinence syndrome (NAS) than treatment with methadone. The limited research suggests that, like methadone, buprenorphine is compatible with breastfeeding. Data available thus far suggest that there are no deleterious effects of in utero buprenorphine exposure on infant development.

CONCLUSIONS

While buprenorphine produces a less severe neonatal abstinence syndrome than methadone, both methadone and buprenorphine are important parts of a complete comprehensive treatment approach for opioid-dependent pregnant women.

Management of women treated with buprenorphine during pregnancy

The management of pregnancy and delivery of a woman on opiate-substitution therapy with buprenorphine requires a coordinated team approach by social services, addiction medicine, obstetrics, and pediatrics. Her obstetrical care is further complicated by the unique pharmacology of buprenorphine and the issues of pain management. Obstetrical providers should be familiar with the complex issues surrounding the optimal care of these women.

The relation between delivery type and cord blood levels of chitotriosidase and Troponin T

The operative deliveries can expose the fetus to acute and systemic hypoxia along with an increase in perinatal morbidity. The aim of this study was to reveal any relationship between delivery type and Chitotriosidase and Troponin T levels in cord blood. Ninety babies born in Ankara Etlik Maternity and Women’s Health Teaching Hospital were involved in the study. The babies were divided into three groups; Group 1: Normal vaginal; Group 2: Caesarean section; Group 3: Forceps application. Cord blood samples were drawn from umbilical arteries of the babies soon after the birth. Chitotriosidase enzyme activities in group 3 (141 nmol/ml/h (0–246)) were found higher than groups 1 (100 nmol/ml/h (0–208)) and 2 (91 nmol/ml/h (0–202)) (p<0.01 and p<0.03 respectively). Although cardiac Troponin T levels were higher in group 3, the difference among groups was not statistically significant (p=0.79). Acute or systemic hypoxic exposure of the organism gives rise to a microvascular response characterized by interactions between leukocytes and endothelium. We are hypothesizing that the high levels of chitotriosidase found in the forceps group were due to hypoxia, and that chitotriosidase level can be used as a marker of acute and systemic hypoxia.