Israel Medical Association Journal

Background: The need for postnatal monitoring of infants exposed to intrauterine beta blockers (BBs) has not been clearly defined.

Objectives: To evaluate infants exposed to intrauterine BBs in order to estimate the need for postnatal monitoring.

Methods: This retrospective case-control study comprised 153 term infants born to mothers who had been treated with BBs during pregnancy. Treatment indications included hypertension 76 mothers (49.7%), cardiac arrhythmias 48 (31.4%), rheumatic heart disease 14 (9.1%), cardiomyopathy 11 (7.2%) and migraine 4 (2.6%). The controls were infants of mothers with hypertension not exposed to BBs who were born at the same gestational age and born closest (before or after) to the matched infant in the study group.

Results: Compared to the control group, the infants in the study group had a higher prevalence of early asymptomatic hypoglycemia (study 30.7% vs. control 18.3%, P = 0.016), short symptomatic bradycardia events, other cardiac manifestations (P = 0.016), and longer hospitalization (P < 0.001). No life-threatening medical conditions were documented. The birth weight was significantly lower for the high-dose subgroup compared to the low-dose subgroup (P = 0.03), and the high-dose subgroup had a higher incidence of small-for-gestational-age (P = 0.02).

Conclusions: No alarming or life-threatening medical conditions were observed among term infants born to BB treated mothers. These infants can be safely observed for 48 hours after birth close to their mothers in the maternity ward. Glucose follow-up is needed, especially in the first hours of life.

Background: Phototherapy is considered the standard of care for neonatal jaundice. However, its short term cardiorespiratory effects have not been studied thoroughly.

Objectives: To assess the cardiorespiratory effect of phototherapy during sleep in term infants with physiologic jaundice.

Methods: We performed two polysomnography studies during 3 hours sleep in 10 healthy term infants with physiologic jaundice; each infant served as his/her own control. The first study was performed just prior to phototherapy and the second study during phototherapy 24 hours later. Heart and respiratory rates, type and duration of apneas, and arterial oxygen saturation were analyzed during active and quiet sleep.

Results: Term infants (gestational age 38.6 ± 1.4 weeks, birth weight 3.2 ± 0.5 kg) underwent the two polysomnography studies within a short time interval and had a comparable bilrubin level (3.6 ± 0.8 and 4.5 ± 0.8 days; 14.5 ± 1.4 and 13.8 ± 2.1 mg/dl, P = NS, respectively). There was no difference in sleeping time or the fraction of active and quiet sleep before or during phototherapy. During active sleep under phototherapy there was a significant decrease in respiratory rate and increase in heart rate (54.3 ± 10.3 vs. 49.1 ± 10.8 breaths/minute, and 125.9 ± 11.7 vs. 129.7 ± 15.3 beats/minute, respectively, P < 0.05), as well as a decrease in respiratory effort in response to apnea. These effects were not found during quiet sleep. Phototherapy had no significant effect on oxygen saturation, apnea rate or periodic breathing in either sleep state. No clinical significant apnea or bradycardia occurred.

Conclusions: Phototherapy affected the cardiorespiratory activity during active sleep but not during quiet sleep in term infants with physiologic jaundice. These effects do not seem to have clinical significance in "real-life" conditions.