Fiberoptic phototherapy versus conventional daylight phototherapy for hyperbilirubinemia of term newborns.

The efficacy and wavelengths of fiberoptic phototherapy and conventional daylight phototherapy were compared in a relatively larger series of term newborns with nonhemolytic and significant hyperbilirubinemia than reported in previous studies. One hundred and nine term newborns were randomly assigned to receive either fiberoptic phototherapy on a fiberoptic phototherapy pad or overhead conventional phototherapy consisting of five daylight fluorescent lamps. Although the average spectral irradiance measured during the study period was significantly greater in the fiberoptic phototherapy group (9.2+/-1.2 microW/cm2/nm vs 7.1+/-1.1 microW/cm2/mm, p < 0.05), conventional phototherapy was significantly more effective in decreasing bilirubin levels: the duration of exposure to phototherapy was significantly shorter (49.4+/-14.4 hours vs 61+/-13.1 hours, p < 0.05), and overall bilirubin decline rate as mg/dl/h and percent/h was significantly greater in the conventional phototherapy group (0.15+/-0.06 mg/dl/h vs 0.11+/-0.05 mg/dl/h, and 0.81+/-0.34 percent/h vs 0.60+/-0.28 percent/h, p < 0.05). There were four failures of phototherapy in the fiberoptic phototherapy group whereas no phototherapy failure was observed in the conventional phototherapy group (p < 0.05). The emission spectrum of the daylight fluorescent lamp revealed a broad emission between the violet and red spectra with tiny narrow peak emission bands in 405 nm, 436 nm, 546 nm and 577 nm, while a broad emission through the blue and green wavelengths (mainly in the green spectrum) without any peak emissions was detected in the tungsten-halogen lamp of the fiberoptic phototherapy system. Conventional phototherapy with daylight fluorescent lamps should be preferred to fiberoptic phototherapy administered with fiberoptic phototherapy and in the treatment of term newborns with nonhemolytic hyperbilirubinemia.     

Double versus single phototherapy in term newborns with significant hyperbilirubinemia

The efficacy of double phototherapy, in the form of conventional phototherapy with special blue light plus fiberoptic phototherapy, was compared with conventional phototherapy consisting of special blue lamps alone in a relatively larger series of term newborns with significant hyperbilirubinemia. During the study period the sum of the average spectral irradiances in the double phototherapy group was significantly higher than that of the single phototherapy group (p < 0.05). Phototherapy was effective in decreasing bilirubin levels in both groups, but the response was greater in the double phototherapy group; the duration of exposure to phototherapy was significantly shorter (31.2 +/- 8.5 vs. 38.98 +/- 14.7 h, p < 0.05), and the overall bilirubin decline rate as mumol/l/h and per cent/h was significantly greater in the double phototherapy group (4.1 +/- 1.37 vs. 3.3 +/- 0.86 mumol/l/h, and 1.29 +/- 0.38 vs. 1.02 +/- 0.44 per cent/h, p < 0.05). In phototherapy treatment of term newborns with significant hyperbilirubinemia, double phototherapy provided more rapid and effective bilirubin reduction than conventional phototherapy alone due to higher spectral irradiance and larger body surface area exposed to phototherapy. The value of double phototherapy in the treatment of newborns with hemolytic hyperbilirubinemia remains to be determined.     

Formation of photoproducts and cytotoxicity of bilirubin irradiated with turquoise and blue phototherapy light

AIM: To compare a new turquoise ("green") fluorescent phototherapy lamp (490 nm) with a conventional blue phototherapy lamp (450 nm) with respect to cytotoxicity and photochemical effects of bilirubin. METHODS: Mouse lymphoma cells (L5178Y-R) in the presence of bilirubin solutions were exposed to phototherapy light. Occurrence of necrosis and apoptosis, reduction of mitotic index and inhibited cell growth was assayed by appropriate methods. The presence of bilirubin and its photoisomers was measured by high-pressure liquid chromatography analysis and absorption spectroscopy. RESULTS: At constant and equal light irradiances, the cytotoxic effects in the presence of bilirubin bound to human serum albumin showed that the green lamp caused significantly less necrosis (n = 4, p < 0.05) and less inhibition of cell multiplication (n = 3, p < 0.05) than the blue lamp. A slightly lower apoptotic fraction, although not statistically significant, was observed in cells exposed to the blue lamp. Photo-oxidation of bilirubin was more prominent with blue light irradiation. The photoequilibria between geometric isomers of bilirubin were different for the two lamps; more geometric photoisomers were formed by blue irradiation (n = 6, p < 0.05). The amounts of the most water-soluble isomers (presumably mainly lumirubin) were rather similar for the two lamps. CONCLUSION: The two lamps were similar in the formation of therapeutically relevant photoproducts, but the blue lamp showed potential in forming more photo-oxidation products and in causing more severe cellular damage in the presence of bilirubin.     

Clinical usefulness of high intensity green light phototherapy in the treatment of neonatal jaundice

Two matched groups of term newborn infants with idiopathic jaundice were subjected to intensive double direction green or blue light phototherapy (PT). The efficacy of treatment was expressed as rate of decline of serum bilirubin concentration after 6, 12 and 24 h of light exposure. More rapid response was obtained using conventional blue lamps (Philips TL/20W/52) than green lamps (Sylvania F20T12/G). Whole duration of PT was significantly shorter using blue lamps (P<0.05). However, less postphototherapy rebound was observed in babies treated with green light PT. It can be concluded that green light PT is useful but not preferable to blue light PT for clinical use in the treatment of neonatal jaundice.     

Fibreoptic phototherapy in the management of jaundice in low birthweight neonates

A fibreoptic phototherapy device has been compared with conventional white and special blue fluorescent phototherapy lamps to evaluate its efficacy in lowering serum bilirubin levels in low-birthweight neonates. Fibreoptic phototherapy was found to be as effective 21s white light and less effective than blue light, as assessed by (i) the bilirubin concentration after 24 h of phototherapy and at the end of phototherapy, (ii) the duration of phototherapy, (iii) the percentage daily decline rate and (iv) the overall percentage decline rate ( p < 0.05). There were no failures of phototherapy and the need for re-exposure was low (4.7% of the total sample), with no difference between groups. The fibreoptic approach represents a promising way to aggregate synergically the most recent optical technologies and develop a modern, efficient and caring phototherapy system for low-birthweight infants.     

An alternative phototherapy light combination

Combinations of fluorescent lamps for phototherapy were evaluated in order to select one that maximizes blue light content (400 to 500 nanometers) for most effective photodegradation of bilirubin, maintains acceptable color balance for observing infant skin color, and requires minimal lamp replacement for low maintenance cost. The combination that best achieves these objectives consists of four special blue (Westinghouse F20T12-BB) and four broad spectrum (Verd-A-Ray F20T12-CC) lamps that produce blue radiation in excess of an array of eight conventional blue lamps, a spectrum closely approximating that of natural light, and at least 80% of the original blue radiation after 2,100 hours of use.     

Intensified phototherapy using daylight fluorescent lamps

Jaundice is a common reason for therapeutic intervention in newborn infants and phototherapy is effective treatment if enough light energy is delivered to a skin surface area of sufficient size. Narrow spectrum blue light is superior to white light, but in developing countries fluorescent blue lamps often have to be imported and are much more expensive than white lamps. We developed a phototherapy unit in which seven daylight fluorescent tubes are placed immediately under the floor of a transparent plexiglass crib. The efficacy of this unit, delivering approximately 19 microW/cm2/nm, was compared with that of two conventional phototherapy units using overhead lamps placed 35 cm above the infants. One unit used daylight fluorescent tubes and delivered approximately 4 microW/cm2/nm, the other unit used special blue fluorescent tubes and delivered approximately 22 microW/cm2/nm. Fifty-one infants were included in the analyses, all of them breastfed on demand. Serum bilirubin levels were determined spectrophotometrically at 0, 12 and 24 h. The decrement in serum bilirubin concentrations was significantly greater in infants undergoing phototherapy with the new device or with special blue lamps compared to conventional overhead daylight lamps (p < 0.001 both at 12 and at 24 h). We conclude that highly efficient phototherapy may be delivered with daylight fluorescent lamps placed in very close proximity to the patient. Thus, lack of access to expensive imported special blue lamps does not preclude delivery of effective phototherapy in developing countries.     

On the efficacy of various irradiation regimens in phototherapy of neonatal hyperbilirubinaemia

The efficacy of various irradiation regimens in phototherapy of neonatal hyperbilirubinaemia was analysed. One hundred and one newborns were assigned to three groups at random. The best results were achieved when six special blue fluorescent lamps were used and the sides of the incubator were draped with white cloth to reflect the light diffusely. This simple measure increased the therapeutic effect by approx. 35%. Compared to standard phototherapy units equipped with fluorescent lights, a halide lamp was no more effective. The results of the clinical trial confirm the conclusions drawn from measurements, published previously. According to those findings, irradiating large areas of skin as homogeneously as possible should produce optinum results. Using a lamp with a large surface in combination with diffusely reflecting areas should best meet this requirement.     

A clinical trial of fiberoptic phototherapy vs conventional phototherapy.

We conducted a randomized, controlled trial to compare fiberoptic phototherapy with conventional phototherapy in healthy jaundiced newborns with birth weights greater than 2500 g. Twelve patients received fiberoptic phototherapy and 14 patients received conventional phototherapy. There were no significant differences between the groups with respect to birth weight, gestational age, feeding method, presence of hemolytic disease, hematocrit, reticulocyte count, or initial serum bilirubin level. Measured irradiance at 425 to 475 nm for conventional phototherapy was greater than that of fiberoptic phototherapy (9.2 +/- 0.9 microW/cm2 per nanometer vs 8.2 +/- 1.2 microW/cm2 per nanometer). Both types of phototherapy lowered the level of serum bilirubin after 18 hours of therapy (fiberoptic group, from 231 +/- 29 to 210 +/- 24 mumol/L; conventional group, from 231 +/- 21 to 188 +/- 26 mumol/L), but the mean serum bilirubin level was lower after 18 hours of therapy in the conventional phototherapy group (188 +/- 26 vs 210 +/- 24 mumol/L). There were no side effects in either group of newborns. Both methods of phototherapy decreased the serum bilirubin level, but conventional phototherapy did so more effectively, probably because of its greater irradiance.     

Phototherapy in the management of neonatal hyperbilirubinemia: efficacy with light sources emitting more than 500 nanometers

The clinical action of green fluorescent lamps, properly filtered to remove wavelengths of less than 500 nm, was investigated in a group of 23 newborns with different initial serum bilirubin concentrations. The serum bilirubin levels were measured at 6, 12, 24, and 48 hours after the beginning of phototherapy. These results are compared with those obtained, under the same experimental conditions, in a group exposed to commercial green lamps. Similar bilirubin decline rates were observed in the two experiments. In general, these data confirm the satisfactory clinical efficacy of the green light in phototherapy and prove, in particular, that the blue component present in the emission spectrum of the commercial green lamps has a negligible effect on the bilirubin degradation process.     

Efficacy of phototherapy for hyperbilirubinaemia in infants with the respiratory distress syndrome

Objectives: To evaluate the efficacy of phototherapy for hyperbilirubinaemia in preterm infants with and without the respiratory distress syndrome (RDS).
Methodology: Prospective cohort study of preterm infants cared for at Kandang Kerbau Hospital, Singapore: 170 with RDS and 477 without RDS, sepsis or other complications (control group) presenting with non-haemolytic hyperbilirubinaemia at about the same time were exposed to daylight phototherapy when bilirubin concentrations exceeded 255 μmol/L or 222 μmol/L if <48h of age. Bilirubin values were monitored 6-hourly during exposure, and daily for at least 2 days postphototherapy.
Results The infants were comparable in birthweight, gestational age, postnatal age, haemoglobin, haematocrit and bilirubin values, at start. The response to phototherapy of the infants with RDS was comparable to that of the well preterm infants; the duration of exposure was 50.1 ± 1.6 (mean ± s.e.m.) versus 50.1 ± 1.4 h, 24-hour decline rate 25.71 ± 1.29% versus 26.32 ± 0.65, and overall decline rate 0.96± 0.03%/h versus 0.95±0.02%/h.
Conclusion The presence of RDS did not affect the efficacy of phototherapy for neonatal hyperbilirubinaemia in preterm infants.     

Dermal bilirubin kinetics during phototherapy in term neonates

Aim: To investigate dermal bilirubin kinetics during phototherapy in the presence of neonatal indirect hyperbilirubinaemia. Methods: 33 neonates with non-haemolytic indirect hyperbilirubinaemia, who required phototherapy, were included in the study. Phototherapy modules containing four normal and four blue fluorescent lamps were used during the study. The transcutaneous bilirubin index (TcBI) was measured in an area of the forehead covered by a 2.5 cm diameter opaque patch and a nearby exposed site. The TcBI obtained from patched and unpatched areas and simultaneous serum bilirubin (SB) concentrations were measured before the start of phototherapy and after 6, 12, 18, 30, 42 and 66 h of phototherapy. Results: SB concentration and the TcBI from the unpatched area decreased significantly during the first 6 h of exposure, while the TcBI obtained from the patched area decreased significantly after 12 h. The TcBI from the unpatched area was consistently lower than that from the patched area during phototherapy. After the onset of phototherapy, there was a weak, non-significant correlation between SB concentrations and the TcBI from patched and unpatched areas.

Conclusion: Phototherapy was effective for both patched and unpatched areas, but the rate of decline was slower in patched areas, only becoming significant in the second 6 h of treatment. There was no significant correlation between the levels of SB and TcBI after the onset of phototherapy, and therefore the use of TcBI cannot be recommended as a surrogate measure of SB.     

Phototherapy for ABO haemolytic hyperbilirubinaemia.

The efficacy of 'standard' daylight phototherapy and 'high intensity' blue light phototherapy for neonatal jaundice from ABO-HD, or of a non-haemolytic nature was evaluated. Altogether 77 full-term infants with ABO-HD and 3,020 with non-haemolytic jaundice were studied. Both groups of infants responded well to standard daylight phototherapy; the response in non-haemolytic hyperbilirubinaemia was significantly greater. High intensity blue light phototherapy was significantly more effective in reducing bilirubin levels than standard daylight phototherapy in both group of infants with no failure being encountered. Four infants with non-haemolytic jaundice did not respond adequately to white light (1.4/1,000); they needed high intensity blue light for adequate response. Bilirubin rebound was mild. Four infants in the blue light group needed a second exposure (28.3/1,000) compared with 20 in the white light group (6.9/1,000), a difference that was significant. Standard white light phototherapy is usually adequate for ABO-HD as well as non-haemolytic hyperbilirubinaemia. High intensity blue light would be preferable where a more rapid and greater response is desirable.     

A new blue light-emitting phototherapy device: a prospective randomized controlled study

OBJECTIVE: To evaluate the efficacy of a new phototherapy light source with a narrow luminous blue spectrum. The device, made with high-intensity gallium nitride light-emitting diodes (LEDs), was compared with conventional phototherapy at similar light intensities. SETTING: Two university-affiliated community hospitals in Jerusalem. DESIGN: Prospective open randomized study. PARTICIPANTS: Sixty-nine jaundiced, but otherwise healthy, term infants who met the entry criteria for phototherapy set by the American Academy of Pediatrics' Practice Parameter. MAIN OUTCOME MEASURES: The duration of phototherapy and the rate of decrease in total serum bilirubin (TSB) concentration. RESULTS: The mean TSB concentrations at initiation and termination of treatment did not differ between newborns receiving LED and those receiving conventional phototherapy. The duration of phototherapy and the rate of decrease in TSB concentration were not statistically different in the 2 groups. The average rate of decrease in TSB after adjustment by a linear regression analysis for confounding factors was -3.16 micromol/L/h (95% confidence limits -4.81, -1.51) in newborns receiving LED phototherapy compared with -2.19 micromol/L/h (-3.99, -0.40) in those treated with conventional phototherapy (P <.14). No side effects were noted in any of the newborns. CONCLUSIONS: The blue gallium nitride LED device is as effective as conventional phototherapy and is readily accepted by nursing staff. Future LED phototherapy devices can provide much higher irradiance, and thus greater efficacy, and offer a new highly versatile approach to the treatment of jaundice.     

Phototherapy for neonatal jaundice: clinical equivalence of fluorescent green and "special" blue lamps

The relative efficacy of fluorescent green (Sylvania F20T12/G) and "special" blue (Westinghouse F20T12/BB) lamps in the phototherapy of jaundiced neonates was investigated. Two groups of low birth weight infants with a mean gestational age of 35 weeks and mean birth weight of 1930 gm, who developed hyperbilirubinemia within the first 5 days of life, were given green or blue lamp phototherapy under the same irradiation conditions. No statistically significant difference in plasma bilirubin concentrations was found between the two groups after 24 or 48 hours of treatment. Because recent measurements indicate that green lamps are much less efficient than special blue lamps for the production of Z, E isomers of bilirubin in vitro and in vivo, the clinical equivalence of these two types of lamps seems to support the hypothesis that production of structural photoisomers of bilirubin is the main mechanism of phototherapy in humans. Therefore, fluorescent green lamps provide an alternative to special blue lamps for treatment of neonatal hyperbilirubinemia.     

Efficacy of "high-intensity" blue-light and "standard" daylight phototherapy for non-haemolytic hyperbilirubinaemia

We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.     

Cells, bilirubin and light: formation of bilirubin photoproducts and cellular damage at defined wavelengths

Christensen T, Kinn G, Granli T, Amundsen I. Cells, bilirubin and light: formation of bilirubin photoproducts and cellular damage at defined wavelengths. Acta Paediatr 1994;83:7–12. Stockholm. ISSN 0803–5253
Cultured cells from one human and one murine cell line were treated with bilirubin and irradiated with visible light of different wavelengths, either from phototherapy lamps or from a Xenon/Mercury lamp equipped with a monochromator. Bilirubin bound to human serum albumin was also irradiated with light. After irradiation, the bilirubin and its photoisomers were extracted and analysed with High Pressure Liquid Chromatography. The formation of single strand breaks in the DNA of treated cells was studied using a fluorescence marker. Cytotoxicity in the mouse skin cell line was measured by loss of the ability to form visible colonies in vitro. Green light exposure favours the production of lumirubin, while blue light causes more DNA damage and cytotoxicity. Green light may be more efficient and safer than shorter wavelength exposure when treating jaundiced newborns with phototherapy.     

Efficacy and safety of the "integral" phototherapy for neonatal hyperbilirubinemia. Results of a follow-up at 6 years of age

One hundred and ten full-term newborns were treated with integral phototherapy (IP) in the first week of life for hyperbilirubinemia (peak bilirubin concentration, 19.5 +/- 2.8 mg/dl). IP was provided by an apparatus which irradiated the infants over the entire skin surface with four visible blue light lamps placed around the body at a mean distance of only 20 cm. The irradiance of the lamps at the skin surface was 0.350 mW/sq cm, in the wavelength range between 425 and 475 nm. The IP resulted in a 48-hour bilirubin decline rate of 0.163 mg/dl/h. After a mean exposure of 78 +/- 32 h, the mean plasma bilirubin level was 8.4 +/- 0.8 mg/dl. One hundred and ten comparable nonjaundiced infants were studied as controls. At 6 years of age, both groups of subjects were called for a follow-up concerning growth, visual, and hearing functions, and neuro-developmental status. The follow-up was completed in 81 children of the IP group (73.6%) and in 89 of the controls (80.6%). There were no significant differences in the studied parameters between the two groups. The study concludes that IP appears to be an effective and safe treatment for jaundiced infants. IP employs less radiant energy from the lamp source than the traditional apparatus, but delivers this energy to a larger skin surface area.     

Management of phototherapy for neonatal hyperbilirubinemia: Is a new radiometer applicable for all wavelengths and light source types?

Background: To evaluate the clinical effects of phototherapy for neonatal hyperbilirubinemia, it is necessary to measure the rate of cyclobilirubin production, which represents the main photochemical pathway of bilirubin metabolism. Since the Atom Phototherapy Analyzer can be used to calculate the theoretical relative light energy of irradiance as a means of assessing the cyclobilirubin production rate for each wavelength spectrum, the clinical effect of phototherapy can be evaluated regardless of the light source type. Using the Atom Phototherapy Analyzer, the correlation between the irradiance of various light sources with different peak wavelengths and the rate of cyclobilirubin production was investigated in vitro. We also investigated the utility of green LED in vitro. Methods: A bilirubin‐albumin complex solution was prepared, poured into tubes, and irradiated using various light sources. All light sources used were bed‐type phototherapy devices; that is, green and blue LED and green and blue fluorescence tubes. The concentrations of photoisomers were measured after irradiation and compared with the irradiance of the light sources. Results: The irradiance measured by the Atom Phototherapy Analyzer decreased in the following order: blue fluorescence tube > green LED > blue LED > green fluorescence tube. The cyclobilirubin production rates and irradiance values of the light sources were significantly positively correlated (R²= 0.93, P < 0.05). Conclusion: Our data indicate that the Atom Phototherapy Analyzer can be used to objectively evaluate the effects of phototherapy using various light sources. Further, the effects of green LED were similar to those of other light sources in vitro.     

Bilirubin-albumin binding affinity and serum albumin concentration during intensive phototherapy (blue double light) in jaundiced newborn infants

Thirty newborn infants with normal birth weights and uncomplicated hyperbilirubinaemia were studied. Twenty three of these were treated continuously for 24h with intensive phototherapy (blue double light), and seven untreated infants served as controls. During the treatment the serum concentrations of total bilirubin and unbound bilirubin in diluted serum measured by the peroxidase method were markedly reduced. The binding affinity of bilirubin to its high affinity site on serum albumin was not affected. During the treatment a slight decrease of the serum albumin concentration occurred, and the possible causes of this observation are discussed.