Adverse neonatal effects of maternal labetalol treatment

Naringenin prevents pregnancy-induced hypertension via suppression of JAK/STAT3 signalling pathway in mice

BACKGROUND

Pregnancy-induced hypertension (PIH) is characterized by high blood pressure during pregnancy, which causes perinatal and maternal mortality. Inflammation, oxidative stress and the JAK2/STAT3 signalling pathway have been reported to play critical roles in the pathogenies of PIH. Due to the safety and side effects of current treatments for PIH, searching for new therapeutic agents is urgently needed. Naringenin is a flavonoid with anti-inflammation and anti-oxidation activities. In the current study, the effects of naringenin on PIH were investigated.

METHODS

We established the PIH mouse model and administrated naringenin to these mice. The blood pressure, total urine protein, plasma levels of vasodilation converting enzyme (VCE), α-1A adrenergic receptor (α-ADR) and angiotensin, inflammatory cytokines, oxidative stress markers were measured. The protein levels of reactive oxygen species proto-oncogene 1 (ROS1), superoxide dismutase 2 (SOD2), signal transducer and activator of transcription 3 (STAT3), phospho-STAT3, Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP-1), Janus kinase 2 (JAK2) and phospho-JAK2, in vascular endothelium cells were detected by western blot.

RESULTS

Administration of naringenin significantly decreased blood pressure, total urine protein level, plasma levels of VCE, α-ADR and angiotensin in PIH mice. Naringenin decreased serum levels of pro-inflammatory cytokines interleukin (IL)-2, IL-6 and tumour necrosis factor alpha (TNF-α), while increased IL-10. Naringenin decreased serum levels of ROS, endothelin while increased SOD and nitric oxide levels. Western blot analysis showed that naringenin inhibited ROS expression, while increased SOD expression in vascular endothelial cells of mice. In addition, western blot also showed that naringenin inhibited JAK2/STAT3 signalling by suppressing SHP-1 expression in vascular endothelial cells of mice.

CONCLUSION

Naringenin suppressed the activation of JAK2/STAT3 signalling pathway and promoted SHP-1 expression, leading to ameliorated hypertension in pregnancy.

Distinct outcomes of labetalol exposed infants: case reports and systematic review

BACKGROUND

The adverse effects of long-term maternal exposure of labetalol on neonates have been recognized clinically. But there are few systematic studies on their clinical demonstrations and potential mechanisms.

METHODS

A death case of an infant with long-term maternal labetalol exposure was reported and compared with two case reports from the literature. A systematic literature review was carried out followed by a retrospective analysis on neonatal labetalol withdrawal effects.

RESULTS

It was discovered that labetalol withdrawal effects initially cause various degrees of hypotension, hypoglycemia, and bradycardia among exposed neonates. Some life-threatening cases can also occur within 1 week after birth. Long-term maternal exposure of labetalol, preterm infants with birth asphyxia, acidosis, hypoalbuminemia, and cardiac defects are their primary features. Possible mechanisms were concluded as labetalol-induced effects on the vascular and sympathetic nervous system as well as tissue oxygen extraction.

CONCLUSIONS

Neonatal labetalol withdrawal effects include early-onset and late-onset demonstrations, the latter can be life-threatening. A possible mechanism is multiple factors induced imbalance of sympathetic homeostasis increases neonatal vulnerability to common stresses. Long-term exposed preterm infants complicated with asphyxia, acidosis, hypoalbuminemia and cardiac defects, should be provided with intense care during the first week after birth. Further work is necessary to enrich this hypothesis.

Neonatal side effects of maternal labetalol treatment in severe preeclampsia

OBJECTIVE

Labetalol is often used in severe preeclampsia (PE). Hypotension, bradycardia and hypoglycemia are feared neonatal side effects, but may also occur in (preterm) infants regardless of labetalol exposure. We analyzed the possible association between intrauterine labetalol exposure and such side effects.

STUDY DESIGN

From 1 January 2003 through 31 March 2008, all infants from mothers suffering severe PE admitted to one tertiary care center were included. Severe PE was defined according to the International Society for the Study of Hypertension in Pregnancy (ISSHP) criteria. Infants exposed to labetalol in utero (labetalol infants) were compared with infants, who were not exposed to labetalol (controls). Neonatal records were reviewed for hypotension (RR<mean gestational age in weeks), bradycardia (heartrate<100/min) and hypoglycaemia (glucose<2.7 mmol/L) in the first 48 postnatal hours.

RESULTS

Of 109 infants, 55 had been exposed to labetalol, whereas 54 were not (controls). Gestational age at delivery and birthweight were similar in both groups (31.8 vs. 32.8 weeks (p=0.06) and 1510 vs. 1639 grams (p=0.25), respectively for the labetalol vs. control group). Hypotension occurred significantly more in conjunction with labetalol exposure (16, (29.1%) vs. 4 (7.4%); p=0.003), irrespective of the route of administration. Patent ductus arteriosus (PDA) was present in 9 (56%) of hypotensive labetalol infants compared to 1 (24%) infant in the hypotensive control group (NS). In a multivariate regression model, labetalol exposure, the need for intubation and PDA appeared independently associated with hypotension (P<0.001). Hypoglycemia occurred in 26 (47.3%) of labetalol infants and in 23 (42.6%) of control infants (p=0.62). Bradycardia occurred in 4 (7.3%) of labetalol infants and in 1 (1.9%) of control infants (p=0.18). Hypoglycemia was more common in premature infants (n=45 (48,9%) vs. n=4 (23.5%), p=0.05) in both labetalol and control infants.

CONCLUSION

Hypotension is more common after maternal labetalol exposure, regardless of the dosage and route of administration. The need for intubation and the presence of a PDA also play a role. Hypoglycemia is a very common finding in this population and is merely related to prematurity and independent of labetalol exposure as was the incidental occurrence of bradycardia. These findings on the neonatal side effects of maternal labetalol treatment in preeclampsia underline the importance of frequent blood glucose and blood pressure measurements in the first days of life, especially in intubated preterm infants with a PDA.

Medications in pregnancy and lactation: Part 2. Drugs with minimal or unknown human teratogenic effect

This is the second of a two-part series on the use of medication during pregnancy and lactation. Pregnancy risk factors together with an increased incidence of chronic diseases and the rise in mean maternal age predict an increase in medication use during gestation. However, as highlighted in the first installment of this series, relatively few medications have specifically been tested for safety and efficacy during pregnancy, and, therefore, responses to those inquiries can be uninformed and inaccurate. Whereas the first installment provided new insight into the nature of medications with known human teratogenic effects, this part concentrates on drugs with minimal or no known human teratogenic effect. It is important that clinicians become familiar with all of the aspects of the drugs they prescribe, in addition to the controversies surrounding them, through consultation with maternal-fetal medicine specialists and through references and Web sites providing up-to-date information in an effort to promote safer prescribing practices.

Neonatal hypoglycaemia: clinical and legal aspects

Transiently low blood glucose levels are common in the neonatal period and may be considered a normal feature of adaptation to extrauterine life. There is no evidence that this causes brain injury in the absence of concurrent clinical manifestations. Conversely, persistent and severe hypoglycaemia may be associated with other underlying pathologies which themselves predispose to brain injury. Attribution of brain injury therefore requires demonstration of both 'significant' hypoglycaemia and a characteristic resulting pattern of brain injury. The prevention of hypoglycaemic brain injury requires early detection in infants considered 'at risk' and appropriate intervention. No single concentration of plasma glucose can be associated universally with either the appearance of clinical signs or causation of cerebral injury. For this reason we suggest that treatment be based upon 'operational thresholds' and guided by clinical assessment, not by the plasma glucose concentration alone. For example, the infant displaying neurological signs requires more urgent elevation of blood glucose concentration than the 'asymptomatic' one, regardless of the absolute plasma glucose value.

Exposition aux bêtabloquants en fin de grossesse

OBJECTIVES

To analyse neonatal effects after in utero betablockers exposure and the pertinence of recommendations delivered by our team.

POPULATION AND METHODS

We report 44 pregnancies exposed to betablockers during the late pregnancy including the period of delivery about which the Regional Pharmacovigilance Center of Tours (CRPV) was questionned.

RESULTS

Among the 39 children for whom we know the follow up, 22 had neonatal adverse effects of which 19 could be explained by in utero exposure to betablockers i.e. an hypoglycaemia (11 times), a bradycardia (six times), a bradycardia and hypoglycemia (one time) and an hypotension (one time). A drug-related effect was retained for eleven newborns (27%) and another etiology could be evoked in the eight others. The risk of neonatal adverse effects seems to increase in newborns exposed to labetalol (5/11), to betaxolol (1/2) or to propranolol (2/6) or when the dose is high. The eight newborns who had intrauterine growth retardation were generally more often exposed to atenolol than eutrophic newborns. Four babies had malformations.

CONCLUSIONS

Our recommendation was an hospitalization 44 times (100%) to monitor heart rate, blood pressure and glycemia. When the follow-up is known, hospitalization was performed in 88% of the cases. Glycemia, heart rate and blood pressure were monitored in all the hospitalized children and in three of the five not hospitalized children. Our recommendation seems particularly justified with regard to hypoglycemia which is often asymptomatic but whose consequences can be severe. Atenolol often provider of intrauterine growth retardation and labetalol more often at the origin of neonatal adverse effects are probably to avoid during pregnancy.

Cardiovascular Pharmacotherapeutic Considerations During Pregnancy and Lactation

Table 2 summarizes the recommendations regarding the use of cardiovascular drugs during pregnancy and lactation.

Comprehensive management of hypertensive emergencies and urgencies

Despite advances in chronic hypertension management, hypertensive emergencies and urgencies remain as serious complications. Much of this relates to poor compliance with effective antihypertensive management. Hypertensive emergencies and urgencies can also be seen as the initial manifestations of hypertension in pregnancy and in the perioperative period. Multiple classes of intravenous antihypertensive drugs are available to treat hypertensive emergencies, and specific agents may have an advantage in a given clinical situation. Orally active agents are used to treat hypertensive urgencies, and include clonidine, angiotensin-converting enzyme inhibitors, and labetalol. Most patients respond to drug therapy, but problems may arise related to a rapid normalization of blood pressure.

Untoward effects of rapid-acting antihypertensive agents

Cerebral haemorrhage remains a major cause of hypertensive cerebral mortality. Lowering of raised blood pressure is therefore crucial in the clinical management of hypertensive disorders of pregnancy. This article reviews rapid-acting agents employed in life-threatening situations.