Effect of phototherapy on the ductus arteriosus diameter in extremely premature infants: A randomised controlled trial.

Patent ductus arteriosus (PDA) is a common complication among preterm infants (especially birth weight < 1000 g) and is closely associated with mortality and morbidity. Phototherapy (PT) is frequently used in the treatment of jaundice in premature infants in the first week of life. The relationship between PT and PDA has been investigated in a small number of studies but has not been fully elucidated because the studies had varying results. AIM: To examine the effect of PT on parameter (DA diameter, left atrial/aortic root ratio) in premature infants. METHODS: The study was planned as a prospective, randomised, double-blind study. A total of 83 infants <1000 g and < 30 weeks of gestation were included, and they were divided into two groups: the non-shielded and shielded groups. The babies included in the study were evaluated with a Doppler echocardiogram before and after PT. RESULTS: The hemodynamically significant PDA (hs-PDA) and left atrial/aortic root ratio significantly decreased in the shielded group, and the need for treatment due to PDA was significantly lower. The PT times of both groups were similar. CONCLUSION: Shielding application decreases the rate and severity of hs-PDA in extremely premature babies receiving PT.

Cardiovascular changes during phototherapy in newborns.

Phototherapy is the most effective non-invasive method of neonatal hyperbilirubinemia treatment. Application of this method can be associated with side effects including changes in the cardiovascular system. During phototherapy, the primary effects in the cardiovascular system include cutaneous vasodilation leading to skin hyperperfusion and subsequent redistribution of blood. The increased blood flow through the skin is associated with increased transepidermal water loss. Further effects include an increase in cerebral blood flow. Redistribution of blood to the cutaneous bed is compensated by hypoperfusion in the splanchnic area (mostly postprandial) and a significant reduction of the renal blood flow. Regarding closure/reopening of the ductus arteriosus, the results suggest that that phototherapy does not affect ductal patency. During phototherapy the cardiac output can be slightly reduced due to a decreased stroke volume, especially in preterm newborns. Systemic blood pressure is decreased and heart rate is elevated in both preterm and term newborns during phototherapy. The heart rate variability is slightly reduced. Symbolic dynamics analysis of the short-term HRV showed that during phototherapy the activity of the ANS regulating the heart rate is shifted towards the dominancy of the sympathetic activity. The responses in the cardiovascular system of premature/mature newborns without other pathology confirm a well physiologically functioning control of this system, even under specific conditions of phototherapy.

Side Effects of Phototherapy on Neonates.

Phototherapy in neonates for treatment of pathological jaundice is an effective therapeutic tool that is widely used in neonatal units. Over the past years, a greater concern has emerged about the effects on the immune and inflammatory system and its potential genotoxic and side effects, especially the late ones, possibly associated with childhood diseases, showing that this treatment is not as harmless as previously believed. Numerous studies assessing these possible adverse effects of phototherapy on neonates have been published over the past years. Through this review, we seek to analyze what we know about the side effects of phototherapy in the neonatal period. The main causes of jaundice, phototherapy techniques, acute and late side effects, and effects on the immune and inflammatory system were reviewed. It was concluded that phototherapy is not a treatment free of side effects and further studies need to be conducted to elucidate its harmful effects on neonates.

Meta-Analysis of the Effect of Chest Shielding on Preventing Patent Ductus Arteriosus in Premature Infants.

Objective This study aims to perform a meta-analysis of randomized studies to evaluate if chest shielding during phototherapy is associated with decreased incidence of patent ductus arteriosus (PDA) in premature infants. Design/Methods We used published guidelines for the meta-analysis of clinical trials. The search strategy included electronic searches of CINAHL, CENTRAL Cochrane Library, MEDLINE, PubMed, and abstracts presented at the Pediatric Academic Societies. Inclusion criteria were randomized controlled trials (RCTs), quasi-RCTs or cluster RCTs published in English and involving chest shielding during phototherapy in premature infants with PDA as an outcome. Exclusion criteria involved case reports, case series, and multiple publications from the same author. Heterogeneity testing using Q statistics was performed to evaluate the variance between studies. Results Two RCTs met study criteria. There was heterogeneity (I2: 55.4%) between the two trials. Meta-analysis of RCTs using the random effect model demonstrated that chest shielding during phototherapy was associated with decreased incidence of PDA (odds ratio: 0.47, 95% confidence interval: 0.23-0.96). There was no publication bias on Eggers test. Heterogeneity was seen in gestational age, gender, prophylactic use of postnatal indomethacin, duration of phototherapy, and assessment of PDA. Conclusion Chest shielding during phototherapy may be associated with decreased incidence of PDA among premature infants.

A new approach to an old hypothesis; phototherapy does not affect ductal patency via PGE2 and PGI2.

OBJECTIVE: Numerous investigations have demonstrated that phototherapy (PT) directly or indirectly causes ductal patency by photorelaxation effect. In this observational study, we aimed to assess the effect of PT on the incidence of patent ductus arteriosus (PDA) together with prostaglandins (PGE2) and (PGI2) levels in preterm infants. METHODS: Preterm infants whose gestational age<34 weeks and who required PT in the first 3 d of life were enrolled in this prospective study. The clinical signs of PDA, the data of detailed echocardiographic study were recorded and plasma PGE2 and PGI2 levels were measured before and after PT. The outcome measures were the status of ductus arteriosus and alterations of PGE2 and PGI2 levels under the effect of PT. RESULTS: A total of 44 preterm infants were enrolled in the study, of these 21 (47.7%) were in Group 1 (Non-PDA Group) and 23 (52.3%) were in Group 2 (PDA Group). After PT, ductal reopening occurred in three infants (14.3%) in Group 1, while ductus closed in four infants in Group 2 (17.3%). PT does not seem to effect ductal patency for both groups (p=0.250 and p=0.125, respectively). PGE2 levels were not different before and after PT for both groups (p=0.087, p=0.408, respectively). However, PGI2 levels were significantly decreased after PT in both groups (p=0.006, and p=0.003, respectively). CONCLUSION: There was no effect of PT on ductal patency. We can conclude that PGs were eliminated simultaneously with ductal closure and photorelaxation effect did not influence PG levels.

Cardiac output and ductal reopening during phototherapy in preterm infants.

Left ventricular output (LVO), left pulmonary artery blood flow (LPA) and patency of the ductus arteriosus (PDA) were studied with 2D/pulsed Doppler ultrasound before, during and after phototherapy treatment in 27 preterm infants (gestational age < or =32 wk), who were exposed for a minimum of 12 h to phototherapy for non-haemolytic hyperbilirubinemia. In 14 infants (52%) the ductus arteriosus reopened during phototherapy, but ductal patency was not of haemodynamic importance. LVO initially decreased in preterm infants in whom the ductus did not reopen. From 12 h until discontinuation of phototherapy, LVO and LPA were higher than before phototherapy in all infants. After withdrawal of phototherapy, LVO and LPA returned to pre-phototherapy values.

The effect of phototherapy on renal blood flow velocity in preterm infants.

Mean renal blood flow velocity (RBFV) was studied with two-dimensional/ pulsed Doppler ultrasound and relative renal vascular resistance (RVR) was calculated before, during, and after phototherapy treatment in 30 preterm infants (gestational age < or = 32 weeks) who were treated for a minimum of 12 h with phototherapy for nonhemolytic hyperbilirubinemia. RBFV decreased, whereas RVR increased significantly after the initiation of phototherapy. In 'healthy' (nonventilated) infants RBFV and RVR returned to baseline values after discontinuation of phototherapy. Whereas in 'unhealthy' (ventilated) infants, RBFV and RVR did not return to baseline values after discontinuation of phototherapy. In 16 infants (> 50% of the cases) the ductus arteriosus reopened during phototherapy.

Association of patent ductus arteriosus and phototherapy in infants weighing less than 1000 grams.

To determine the relationship of phototherapy and patent ductus arteriosus, we analyzed prospectively collected data on 295 infants with birth weight of 501 to 999 gm admitted from 1984 through 1988. Seventy-four percent were evaluated by an imaging study to aid in the detection of a silent patent ductus arteriosus. Overall incidence of patent ductus arteriosus in the study population was 63%. Infants who received phototherapy (n = 128) had an increased incidence of patent ductus arteriosus compared with those who did not receive phototherapy (76% vs 53%). There was an association of patent ductus arteriosus and phototherapy (p < 0.05) when we analyzed the data with a stepwise regression model that controlled for the effects of gestational age, birth weight, gender, race, diagnosis of hyaline membrane disease, mechanical ventilation, patent ductus arteriosus imaging studies, prophylactic indomethacin, peak total and indirect bilirubin values, and the occurrence of abnormal serum sodium values. We conclude that the use of phototherapy is associated with an increased incidence of patent ductus arteriosus in extremely low birth weight infants.

Phototherapy effect on the incidence of patent ductus arteriosus in premature infants: prevention with chest shielding.

Patent ductus arteriosus is common among premature neonates, especially those with birth weights less than 1,500 g. In vitro, room light inhibits the contraction of immature piglet's ductal rings. Because phototherapy is used frequently from the first days of life to treat jaundice in preterm neonates, we compared the occurrence of patent ductus arteriosus among premature infants exposed to this intense light source with those whose chests were shielded. Seventy-four babies with respiratory distress syndrome were randomly assigned to either a treatment group (chest shielded with aluminum foil while on phototherapy, 36 babies) or control group (no shield, 38 babies). All were on radiant warmers, received mechanical ventilation for respiratory distress syndrome, and phototherapy (Air Shields model PTU 78-1) from day 1 of life. Irradiance was maintained at greater than 4.0 microW/cm2/nm in all cases. Although both groups had similar birth weights, gestational ages, severity of respiratory distress syndrome, intravenous fluid intake, and duration of phototherapy, the incidence of patent ductus arteriosus was significantly less in the shield group (shield 11/36 v No shield 23/38; P = .009). Patent ductus arteriosus murmurs developed in shielded patients at a later date, they required less vigorous treatment (ie, indomethacin), and they had shorter hospitalizations (74 v 85 days; P less than .05). The significant reduction of patent ductus arteriosus with shielding suggests that phototherapy may play a role in the occurrence of patent ductus arteriosus in premature infants. Shielding may be a practical method to decrease this common complication should this initial observation be confirmed.