News review 4. Phototherapy lights for neonatal jaundice : What is new ?
Dr Anu Thukral and Dr Ashok Deorari share their views......

 

Phototherapy is the most common intervention used for the treatment of hyperbilirubinemia. It has become the mainstay of treatment since its introduction in 1958. Light in the range of 400-500nm with a peak at 460±10 nm is considered most effective. The phototherapy units and the type of lamps vary widely. The efficacy is influenced by spectrum, surface area of the infant exposed and irradiance of the light used. Here we shall review current literature of the latest techniques used in phototherapy.

 

Light emitting diode uses high intensity gallium nitrate LED and has many advantages over the conventional phototherapy units - this includes running on a low wattage 9watts, more efficient conversion, longer life time, cost effectiveness and little infrared and no UV ray emission. Maisels MJ et al compared the efficacy of light-emitting diode (LED) phototherapy with special blue fluorescent (BB) tube phototherapy in the treatment of neonatal hyperbilirubinemia.1 they randomized 66 infants term or near term into the two groups and concluded that LED phototherapy is as effective as BB phototherapy in lowering serum bilirubin levels in term and near-term newborn.

 

Martins BM did a study comparing light emitting with a microproceesed phototherapy in preterm neonates with hyperbilirubinemia.2 They randomized 88 infants in the two groups and found that after 24 hours of treatment, a significantly greater number of patients receiving Super LED phototherapy had reached serum bilirubin concentrations low enough to allow withdrawal of treatment (23 vs. 10, p<0.01).

 

Ebbesen F et al did a RCT at their centre in Denmark3 to compare the efficiency of turquoise light with that of TL52 blue in treatment of preterm infants with jaundice at the same level of body irradiance and found that the decrease in serum concentrations of total bilirubin, total bilirubin isomers and the toxic Z, Z-bilirubin was greatest for infants treated with turquoise light. This they related to the deeper penetration and increased production of lumirubin, and E, Z bilirubin.

 

Phototherapy in principle is a relatively simple treatment, however its application is not standardized4 and there are a variety of factors which may lead to suboptimal treatment including phototherapy duration, bedside optimization of device potential to deliver light, phototherapy device characteristics and patient's characteristics. Vreman HJ et al developed and tested a standardized bench method for evaluating the efficacy of some devices. They quantified the in vitro photodegradation rate (expressed as t(1/2)) of unconjugated bilirubin in solution at 37 degrees C during exposure to a given light source at its mean delivered irradiance to the 2D body surface area (BSA) of newborn models. Halogen lamp devices, without and with fiberoptics, were least effective, fluorescent moderately effective and Light-emitting diode (LED)-based devices yielded the shortest t (1/2).

 

To summarize recent evidence suggests:

 

  1. Efficacy of LED phototherapy for treating hyperbilirubinemia in premature infants and term infants is as effective as conventional and perhaps better than halogen spotlight.
  2. LED could be a resource full technique in view of its efficacy and least side effects and cost effectiveness
  3. Turquoise light is better than conventional blue light in the treatment of hyperbilirubinemia but a larger study is required for the same.
  4. Standardized bench method effectively evaluates the relative in vitro efficacy of various devices and may guide further in vitro and in vivo evaluations of devices.

 

1. Randomized controlled trial of light-emitting diode phototherapy.

 

J Perinatol. 2007 Sep; 27(9):565-7. Epub 2007 Jun 28
Maisels MJ, Kring EA, DeRidder J.

 

OBJECTIVE: We wished to compare the efficacy of light-emitting diode (LED) phototherapy with special blue fluorescent (BB) tube phototherapy in the treatment of neonatal hyperbilirubinemia.

 

STUDY DESIGN: We randomly assigned 66 infants >or=35 weeks of gestation to receive phototherapy using an LED device or BB. In addition to phototherapy from above, all infants also received phototherapy from below using four BB tubes or a fiberoptic pad.

 

RESULT: After 15+/-5 h of phototherapy, the rate of decline in the total serum bilirubin (TSB) was 0.35+/-0.25 mg/dl/h in the LED group vs 0.27+/-0.25 mg/dl/h in the BB group (P=0.20).

 

CONCLUSION: LED phototherapy is as effective as BB phototherapy in lowering serum bilirubin levels in term and near-term newborns.

 

2. Efficacy of new micro processed phototherapy system with five high intensity light emitting diodes (Super LED).

 

J Pediatr (Rio J). 2007 May-Jun;83(3):253-8.
Martins BM, de Carvalho M, Moreira ME, Lopes JM.

 

OBJECTIVES: To evaluate the efficacy of a micro processed phototherapy (PT) system with five high intensity light emitting diodes (Super LED) for the treatment of neonatal hyperbilirubinemia of premature infants.

 

METHODS: Randomized clinical trial using Super LED phototherapy in the study group and twin halogen spotlight phototherapy in the control group. A stratified blocked randomization, based on birth weight, was performed. The duration of phototherapy and the rate of decrease of total serum bilirubin (TSB) concentration in the first 24 hours of treatment were the main outcome measures.

 

RESULTS: We studied 88 infants, 44 in the Super LED group and 44 in the halogen spotlight PT group. The demographic characteristics of the patients in both groups were similar. Infants in the Super LED group had a similar mean initial serum bilirubin level (10.1+/-2.4 mg %) to those receiving halogen spotlight treatment (10.9+/-2.0 mg %). After 24 hours of treatment, the decrease in total serum bilirubin levels was significantly greater in the Super LED group (27.9 vs. 10.7%, p <0.01) and duration of phototherapy was significantly shorter in this group (36.8 h vs. 63.8 h, p<0.01). After 24 hours of treatment, a significantly greater number of patients receiving Super LED phototherapy had reached serum bilirubin concentrations low enough to allow withdrawal of treatment (23 vs. 10, p<0.01).

 

CONCLUSIONS: Our results demonstrate that the efficacy of Super LED phototherapy for treating hyperbilirubinemia in premature infants was significantly better than halogen phototherapy.

 

3. Therapeutic effect of turquoise versus blue light with equal irradiance in preterm infants with jaundice.

 

Acta Paediatr. 2007 Jun; 96(6):837-41
Ebbesen F, Madsen P, Støvring S, Hundborg H, Agati G.

 

AIM: To compare the efficiency of turquoise light with that of TL52 blue in treatment of preterm infants with jaundice at the same level of body irradiance.

 

METHODS: Infants with gestational age 28-37 weeks and non-hemolytic hyperbilirubinemia were treated for 24 h with either turquoise light (OSRAM L18W/860 fluorescent lamps) or blue light (Philips TL20W/52 fluorescent lamps). The concentrations of serum total bilirubin and bilirubin isomers were measured by the Vitros routine method and by HPLC, respectively.

 

RESULTS: The decrease in serum concentrations of total bilirubin, total bilirubin isomers and the toxic Z, Z-bilirubin was greatest for infants treated with turquoise light. Further, the increase in Z, E-bilirubin was smaller and there was a trend towards a higher rise in E, Z-bilirubin.

 

CONCLUSIONS:Turquoise light has a greater bilirubin reducing effect than TL52 blue light with equal irradiance, expressed both by serum total bilirubin, total bilirubin isomers and Z, Z-bilirubin, i.e. the turquoise spectral range is more efficient than the blue. This is in accordance with deeper penetration into the skin, lower production of the Z, E-bilirubin and greater production of E, Z-bilirubin and lumirubin, in infants under turquoise light. This suggests, given equal irradiances, that light in the turquoise spectral range is preferable to the TL52 blue in treatment of newborn jaundiced infants.

 

4. Standardized bench method for evaluating the efficacy of phototherapy devices

 

Acta Pediatr. 2008 Mar; 97(3):308-16.
Vreman HJ, Wong RJ, Murdock JR, Stevenson DK.

 

AIM: As phototherapy (PT) devices employ a variety of broadband light sources, we developed and tested a standardized bench method for evaluating the efficacy of some devices.

 

METHODS: To evaluate efficacy, we quantified the in vitro photodegradation rate (expressed as t(1/2)) of unconjugated bilirubin in solution at 37 degrees C during exposure to a given light source at its mean delivered irradiance to the 2D body surface area (BSA) of newborn models. Reproducibility (between-day variation) of the method was determined at irradiance levels from 10 to 70 muW/ cm(2)/nm on three different days.

 

RESULTS: Between-day t (1/2) measurements had coefficients of variation from 3% to 10%. When t(1/2) values were normalized to the exposable 2D horizontal BSA, halogen lamp devices, without and with fiberoptics, were least effective (t(1/2)= 60-108 min and 100-126 min for preterm and term models, respectively). Fluorescent tube devices had t(1/2)= 19-78 min and 25-78 min, for preterm and term models, respectively. Light-emitting diode (LED)-based devices yielded the shortest t(1/2) values (16-24 min) for preterm and term newborn models.

 

CONCLUSIONS: We demonstrated the applicability of the method through the determination of the efficacy of several commercially available PT devices. This standardized method is reproducible and effectively evaluates the relative in vitro efficacy of various devices and may guide further in vitro and in vivo evaluations of devices.