Phototherapy to Prevent Severe Neonatal Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation: Technical Report

The intensity and spectral output of phototherapy devices and its illuminated body surface area (BSA) or “light footprint” impact their potential effectiveness in treating hyperbilirubinemia (Aggregate Evidence Quality Grade A). Clinical effectiveness should be evaluated and monitored during use (Aggregate Evidence Quality Grade A). Blocking the light source or reducing exposed BSA should be avoided (Aggregate Evidence Quality Grade B). Further development of phototherapy devices should focus on the standardization of irradiance meters, improvements in design allowing for parent-infant bonding, and identification of safety limits (minimal and maximal) of light wavelengths and irradiances emitted. Along with the incorporation of new evidence provided in the current 2022 American Academy of Pediatrics “Clinical Practice Guideline Revision for the Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation,”¹  the Committee on the Fetus and Newborn offers this technical report to summarize the principles and application of phototherapy to facilitate safe and effective treatment of neonates with the goal of preventing hyperbilirubinemia and phototherapy-associated adverse effects.

Phototherapy is prescribed for treating neonatal hyperbilirubinemia and is performed by exposing newborn infants to light in the blue-green wavelength range (460–490 nm), preferably at an optimal peak of 478 nm^2,3  and at an irradiance of 25 to 35 µW/cm²/nm to at least 1 surface of the body (ventral or dorsal).⁴  The photoconversion of the unconjugated bilirubin molecule mostly occurs in the microcirculation of the skin with almost immediate photo-isomerization to the excretable water soluble 4E,15Z photoisomer, peaking within 120 minutes. About 20% of bilirubin is converted to the 4Z,15E photoisomer and 5% to lumirubin. This transformation results in a presumably rapid decrease of excessive unconjugated bilirubin concentrations and the subsequent reduction of potential exposure to neurotoxicity.⁵  Further decline in total serum/plasma bilirubin (TSB) concentrations are attributable to natural excretion in bile and stools. Phototherapy is an essential intervention for severe hyperbilirubinemia, especially in neonates at high risk. The timing of intervention is guided by performing serial measurements of TSB concentrations and screening for the presence of intrinsic risk factors for bilirubin neurotoxicity. Although clinical trial data that show that phototherapy directly prevents kernicterus are scant,⁶  there is sufficient evidence that its use reduces the risk of bilirubin neurotoxicity as well as the use of exchange transfusions (particularly in extremely preterm infants).⁶  Failure of response to phototherapy is unusual unless complicated by an increased rate of bilirubin production attributable to the presence of hemolysis or use of inappropriate (or ineffective) phototherapy devices. The available current evidence and consensus for the application of phototherapy can be translated to institutional policies for standardized implementation for its safety and effectiveness. This report outlines a standardized approach to the use of phototherapy consistent with the 2022 American Academy of Pediatrics (AAP) “Clinical Practice Guideline Revision for the Management of Hyperbilirubinemia in the Newborn Infant 35 or More Weeks of Gestation.”¹ 

Clinical trials have validated the efficacy of phototherapy in reducing unconjugated hyperbilirubinemia (TSB >25 mg/dL [>428 µmol/L]). Initiation of phototherapy is clinically determined when a specific range of TSB threshold values based on a newborn infant’s gestational age (in weeks), postnatal age (in hours), and the presence or absence of risk factors associated with bilirubin neurotoxicity is reached.^1,7 

The TSB thresholds should provide a sufficient margin of safety and take into account interlaboratory variations in TSB measurements,⁸  the biologic vulnerability of an individual infant, the rapidity of an infant’s response to phototherapy, and the balance between risks of over- and undertreatment.⁹  The effectiveness of phototherapy depends on the efficacy of the device used and the net gradient between an infant’s rates of bilirubin production and elimination. Phototherapy needs to be delivered in measurable doses (irradiance), which makes it conceptually similar to pharmacotherapy.⁴ 

A wide selection of commercial phototherapy devices is available in the United States that comply with US Food and Drug Administration standards. A complete discussion of devices is beyond the scope of this review; some of the common types of devices are listed for comparison in Table 1. They are best categorized according to their light source: (1) fluorescent-tube devices that emit different colors (cool white daylight, blue, special blue, turquoise, and green) and are straight (F20 T12, 60 cm, 20 W), U-shaped, or spiral-shaped; (2) metal halide bulbs used in spotlights and incubator lights; (3) high-intensity narrow band light-emitting diodes (LEDs) or metal halide bulbs, used with fiberoptic light in pads, blankets, or spotlights; and (4) LEDs incorporated into overhead, underneath, and circumferential (360°) illumination. LED light sources are preferred because they can deliver the recommended specific light wavelengths in narrow bandwidths with minimal heat generation.

Comparisons of commercially available phototherapy devices using in vitro photodegradation methodologies may not accurately predict clinical efficacy because of variable rates of bilirubin production and elimination as well penetration of light through the skin.¹⁰  Factors to consider in prescribing and implementing phototherapy using a particular device include: (1) the emission wavelength range of the light source; (2) the light intensity (dose, irradiance) delivered; (3) the percent exposed BSA of the infant (ventral, dorsal, or both) that can be illuminated; and (4) commercially availability. Efficacy is measured by the rate of reduction in TSB concentrations but may be impacted by variations in infant skin thickness and maturation and hematocrit.¹¹ 

The visible white light spectrum ranges from approximately 400 to 700 nm. The bilirubin molecule absorbs visible light most strongly in the blue region of the spectrum (range: 460–490 nm). Specific peak wavelength around 478 nm is the optimum wavelength for absorption by bilirubin in competition with hemoglobin, skin pigments, and light scattering in the dermis.^4,6  Upon exposure to this blue light, unconjugated bilirubin bound to human serum albumin undergoes efficient, reversible configurational (Z → E) isomerization, and much less efficient structural isomerization to a ring closed product called lumirubin. Both products are found in infants undergoing phototherapy. Yet, there is evidence that the transformation to lumirubin is primarily responsible for the phototherapy effect^4,12,13  (see Appendix II).

Absorption of light transforms unconjugated bilirubin molecules bound to human serum albumin in solution into bilirubin photoproducts (predominantly isomers of bilirubin).^10,13,14  The most effective light is in the blue-to-green (∼460 to 490 nm) region, in which bilirubin absorption is maximal and light penetration of the skin is good.^10,15,16  The original prototype phototherapy device designed and used by Cremer et al¹⁷  resulted in a clinically significant rate of TSB decrease with a blue fluorescent-tube light source with 420- to 480-nm emission.^12,17  More effective narrow-band special blue bulbs (F20T12/BB [General Electric, Westinghouse, Sylvania] or TL52/20W [Phillips]) were subsequently developed and used.^18,19  Most recently, commercial compact fluorescent-tube light sources and devices use LEDs of narrow spectral bandwidths.^19–24  Recent in vitro experiments and clinical studies have provided evidence that administration of light in the blue-green region (478 nm) is optimal, and it is anticipated that this light wavelength will be incorporated into future commercial devices.^2,3,25,26 

Attention to the configuration of marketed devices, the nature of the light source, and overall ambient temperature conditions is required to minimize the risk of hypothermia or hyperthermia. Safety measures may include use of a warmer bed, incubator or kangaroo (skin-to-skin) care, provision of adequate nutrition, and adherence to safe sleep practices.

Devices emitting narrow wavelength light within the blue-green (460 to 490 nm, 478 nm optimal) region of the visible light spectrum are currently the most effective for treating neonatal hyperbilirubinemia.^10,13,27  Lights with broader wavelengths or non-LED light sources may also work, although not as effectively, and may also be potentially harmful because of production of unnecessary heat and other adverse effects including increased evaporative losses, oxidative stress, and skin DNA damage.^4,28,29  Because hemoglobin serves as a major competitor of bilirubin for light absorption, the efficacy of phototherapy is dependent on the hematocrit. For example, polycythemia could reduce therapeutic efficiency.¹¹ 

Special blue fluorescent tube lights are also effective but do not deliver in a narrow band of light and may be associated with heat and evaporative water loss. Devices that incorporate blue or blue-green (460 to 490 nm) LEDs are the most effective, have a long lifetime (>20 000 hours), low heat output, low infrared (IR) emission, and no ultraviolet (UV) emission.

Commercial phototherapy devices can be configured for clinical use in multiple settings in the hospital. Earlier reports suggested the potential for home use as well,³⁰  but there remains a paucity of evidence comparing the effectiveness of home versus hospital-based phototherapy. However, a recent report³¹  of carefully selected neonates demonstrated home phototherapy can be delivered safely with minimal need for subsequent hospitalization and presumed cost savings. Key factors for successful use of home phototherapy include: the selection of low-risk patients, availability of daily health-supervised visits for which health care providers receive payment to manage equipment and monitor the newborn infant’s well-being, and ability to track serial TSB measurements and provision of family support. Criteria for home phototherapy use are explicitly outlined in the 2022 AAP Clinical Practice Guideline Revision.¹  Infants at any perceived risk for acute bilirubin encephalopathy are not candidates for home treatment and instead may require emergency phototherapy within an inpatient care facility. Other locations include those that provide the ability to initiate and maintain phototherapy during neonatal transport and in the emergency department while awaiting inpatient placement.

Light intensity or energy output of a device is defined as irradiance and refers to the number of photons (spectral energy) that are delivered per unit area (cm²) of exposed skin.⁷  The dose of phototherapy is a measure of the irradiance delivered for a specific duration and exposed BSA. Determination of an in vivo dose-response relationship may be confounded by the optical properties of an infant’s skin and rates of bilirubin production and elimination.⁷  Irradiance is measured with a radiometer (W/cm²) or spectroradiometer (µW/cm²/nm) over a given wavelength band. Table 1 compares the irradiance footprints of the most popular devices in the United States as measured with their specific irradiance meter. It is important to note that the use of radiometers not recommended by the manufacturer may measure wavelengths that do not penetrate skin well or are suboptimal or useless for phototherapy and, therefore, have little or no value.

A direct relationship between irradiance and the rate of in vivo TSB concentration decrease was only described in the report of a study of term “healthy” infants with nonhemolytic hyperbilirubinemia (peak values: 15 to 18 mg/dL [257 to 308 µmol/L]) using fluorescent Philips daylight (TL20W/54), white (TL20W/52), or special blue (TLAK 40W/03) lamps.^32–34  The AAP has recommended that for intensive phototherapy, an irradiance of 30 µW/cm²/nm (range 25 to 35) of blue-green light at around 478 nm in the range 460 to 490 nm be applied.^1,7  Decline in TSB concentrations may flatten as irradiance doses exceed >35 µW/cm²/nm.^32,33  Safety and benefits of much higher doses have yet to be reported and could potentially have adverse effects on tissues and organs, as described in a recent review.³⁵  Currently, no single method is in general use for measuring total phototherapy doses. In addition, the calibration methods, wavelength responses, and geometries when multiple devices are used have not been standardized. Consequently, different radiometers may show different values for the same light source, so, in general, radiometers recommended by the manufacturer of the specific device should be used.¹⁰  Visual estimations of brightness and use of ordinary photometric or colorimetric light meters are inappropriate.^7,27 

Maximal irradiance can be achieved by bringing a light source close to the infant⁷ ; however, halogen or tungsten lights should not be used because of the possibility for heat-generated burns. Furthermore, with some devices (especially spotlights), decreasing the distance to an infant may severely reduce the exposed BSA. Irradiance distribution in the illuminated area (or footprint) of a device is rarely uniform, and measurements taken at the center of the footprint can greatly exceed those at the periphery and are variable among phototherapy devices, especially for spotlights, but in contrast, not for LED devices.⁷  Ideal distance and orientation of the light source are maintained according to the specific manufacturer’s operational recommendations. The irradiance of all lamps decreases variably over time with use; manufacturers may provide useful lifetime estimates to estimate when irradiance may be expected to decrease. A record of therapy provided is best described by duration, number of devices, daily measure at skin level exposure, and percent of BSA exposed.

An infant’s total BSA³⁶  is influenced by their disproportionate head size, especially in the preterm infant. Complete (100%) exposure of the total BSA to light is impractical and limited by use of eye masks and diapers. Circumferential illumination (total BSA exposure of >80%) from devices placed at multiple directions to yield 360° exposure have been achieved. In clinical practice, exposure is usually planar: ventral with overhead light sources or dorsal with phototherapy mattresses or blankets. Approximately 35% of the total BSA (ventral or dorsal) is exposed with either method. Changing the infant’s position while receiving phototherapy may place the infant at risk for unsafe nonsupine sleep positions.³⁷  Several well-designed studies have demonstrated the lack of any beneficial effect of changing infant position under phototherapy.^37–39  Percent of exposed BSA using the most appropriate light source rather than the number of devices (double, triple, etc) is clinically more relevant.^27,28  Use of more than 1 phototherapy device can improve effectiveness by increasing a greater available skin surface illumination, but care must be taken to avoid interference and presence of shadows and, thereby, ensure a uniformly irradiated light footprint.⁷ 

Physical obstruction of light by equipment, such as radiant warmers, head covers, large diapers, eye masks that enclose large areas of the scalp, tape, electrode patches, and insulating plastic covers decrease the exposed BSA. Circumferential phototherapy maximizes the exposed area and is especially effective in infants with extreme hyperbilirubinemia. Combining several types of devices, such as those placed overhead with those placed below the infant or bassinet, such as pads or mattresses, could increase the BSA exposed. For an infant in an incubator, the light emission is best delivered perpendicular to the surface of the incubator to minimize reflectance, shadows, and loss of efficacy.^7,27  The delineation of effectiveness by using single, double, or triple phototherapy fails to account for the specific extent BSA exposed, the specific wavelength of light sources used, and the measured uniformity of irradiance delivered at the skin surface level.

The clinical impact of phototherapy should normally become evident within 4 hours of initiation with an anticipated decrease in TSB concentrations of >2 mg/dL (34 µmol/L). A minimal reduction in the TSB concentration rise may suggest a “plateau effect” and may be considered a partial response.⁷  The rate of clinical response depends on an infant’s rate of bilirubin production (even more so during ongoing hemolysis), enterohepatic circulation, and bilirubin elimination; the degree of tissue bilirubin deposition^32,33,40 ; and the rates of the photochemical reactions of bilirubin. Conversion of bilirubin molecules to nontoxic photoisomers occurs within seconds of light exposure and reaches a plateau by 2 hours.^10,14,41  Timely implementation of phototherapy for excessive hyperbilirubinemia (TSB >25 mg/dL [>428 µmol/L]), even while medical procedures are being conducted, is sometimes referred to as the “crash-cart” approach.^42,43  This rapid implementation practice has been reported to reduce the need for exchange transfusion and possibly minimize the severity of bilirubin neurotoxicity.

Serial measurements of TSB concentrations used to monitor the effectiveness of phototherapy by the timed rate of TSB decline (mg/dL per hour) should be based on the current 2022 AAP Clinical Practice Guideline Revision.¹ 

Phototherapy can be administered continuously or intermittently (ie, cycled). The benefits of either strategy have not been demonstrated consistently in the literature nor opined by clinical case reports and practice options. In view of potential adverse effects of excessive photon exposure, it is prudent to limit the total duration of light exposure or “irradiance dose.” Since the advent of phototherapy, small trials in term or near-term infants have reported that brief light exposure to 15 minutes per hour resulted in equivalent reduction of TSB concentrations as compared with continuous phototherapy^17,44–47 ; this clinical practice for extremely low birth weight infants is currently under investigation. In current practice, total duration of phototherapy is determined by serial monitoring of TSB concentration (dependent of frequency of testing) and its discontinuation once a target TSB concentration is reached.

1. Continuous: uninterrupted exposure (as with “escalation of care”).

2. Continual: brief interruptions for infant handling, parental bonding, and breastfeeding.

3. Intermittent (cycled): timed intervals (in minutes or hours) of nonexposure. Cycled phototherapy in extremely low birth weight infants has been proposed as light exposure is cycled usually at 15 minutes on and 45 minutes off per hour⁴⁸  and is currently under clinical investigation.

Light-emission characteristics of phototherapy devices help in predicting their effectiveness (Aggregate Evidence Quality Grade B, Appendix I). Clinical effectiveness of a specific device, known before use, allows for individualized monitoring during its application (Aggregate Evidence Quality, Grade A) for a safer implementation strategy. Local guidelines (instructions) for routine clinical use should be made available to clinical staff. Obstructing the light source and reducing the exposed BSA must be avoided (Aggregate Evidence Quality, Grade B). Important action items for phototherapy based on contemporary recommendations¹  are summarized in Table 2. These considerations have been incorporated into policies and procedures at several diverse high-resource settings. In low-resource locations, the most relevant evidence-based practice should be sought. The Food and Drug Administration has not approved use of any improvised technologies that have been modified and adapted for cost-savings. Although such improvised devices may be innovative, they still must meet minimum efficacy and safety standards and approval by local institutional regulatory agencies.

A clinician skilled in newborn care should assesses a neonate’s clinical status during phototherapy to ensure adequate hydration and temperature control (especially when heat-generating phototherapy devices are used) as well as providing nutrition by promoting breastfeeding. TSB levels are serially assessed by clinicians who concurrently monitor for onset of progressive signs of acute bilirubin encephalopathy associated with unexpected or sudden onset of extreme hyperbilirubinemia for the infant’s age. These signs include deteriorating or altered feeding patterns, lethargy, inconsolability, high pitched crying, hypotonia or hypertonia, opisthotonus, retrocollis, or fever.¹  As discussed in the 2022 AAP clinical practice guideline revision,¹  although questions have been raised about safety of phototherapy, 6 decades of phototherapy use in newborn infants 35 or more weeks of gestation has not resulted in any clinical evidence of irreversible or serious side effects (discussed below).

Prolonged phototherapy has been associated with increased oxidant stress and lipid peroxidation⁴⁹  and riboflavin deficiency.⁵⁰  Thus, intravenous tubing and infusions that deliver multivitamins and intralipids may require protection from light exposure. Recent clinical reports of speculated adverse outcomes (eg, malignant melanoma, DNA damage, and skin changes), especially when using LED-based devices,²⁹  have yet to be validated.^1,7,27,51,52  Phototherapy does not exacerbate hemolysis.⁵³  Staff should educate parents regarding the care of their newborn infant undergoing phototherapy. Devices must comply with general safety standards listed by the International Electrotechnical Commission.⁵⁴  Key clinical considerations (Table 3) include:

• Positioning: Ideally, newborn infants undergoing phototherapy should adhere to safe, supine sleep positions. Alternating between supine and prone positions does not reduce the duration of phototherapy compared with continuous supine positioning alone.³⁷  Additionally, prone positioning has been associated with an increased risk of sudden infant death³⁸  and is contrary to the established safe sleep practices for infants recommended to parents or caregivers when discharged from the hospital.³⁹ 

• Interruption of phototherapy: Continuous exposure to the light source may be reasonably briefly interrupted and the eye mask removed to allow for feeding and parent-infant bonding.¹ 

• Use of eye masks: Eye masks are used to shield an infant from the glare of the overhead lights. Preventing a theoretical risk of retinal damage has not been proven and may be similar to protection by closed eyelids. Retinal damage has been documented in the unpatched eyes of newborn monkeys exposed to phototherapy, but there are no similar data available from human newborn infants because eye patches have always been used.^55–57  Retinal injury has not been reported after inadvertent displacement of eye masks, but efforts should be made to maintain the eye mask in place.

• Use of diapers: Concerns for the long-term effects of continuous phototherapy exposure of the reproductive system have been raised but not substantiated.^58–60  Diapers are used for hygienic purposes, and not for gonadal protection.

• Other protective considerations: Devices used in environments with high humidity and oxygen must meet electrical and fire hazard safety standards.⁵⁴ 

• Concurrent clinical disorders: Phototherapy is contraindicated in infants with congenital porphyria or those treated with photosensitizing drugs.⁷ 

Sister Jean Ward’s initial observation and practice that sunlight had an ameliorative effect on hyperbilirubinemia led to the development of phototherapy devices. The sun emits blue-green light in the spectrum needed to most effectively convert bilirubin to its water‐soluble isomers for excretion. However, a significant fraction of sunlight is in the UV region (<400 nm), and this potentially damaging radiation can be effectively absorbed by various organic and biologic substances. Recently, the use of window-tinting films, which have the ability to block UVA (315–400 nm) and IR (>700 nm) radiation from the sun and to selectively transmit visible light including therapeutic blue light, was evaluated.⁶¹  Transmission of therapeutic blue-green light (400–520 nm) through films ranged from 24% to 83% compared with unfiltered solar radiation. Studies from countries with limited phototherapy resources have provided evidence in support of filtered sunlight coupled with close monitoring of temperature and overall clinical status. Efficacy of filtered-sunlight phototherapy has been shown in clinical studies in Nigeria,^62–65  and the sun emits blue-green light in the spectrum needed to most effectively convert bilirubin to its water‐soluble isomers for excretion. Home exposure to natural sunlight exposes the infant to unwanted UV and IR radiation. Natural unfiltered sunlight cannot be applied at prescribed dosages. Undressing newborn infants and exposing them to natural sunlight in the home setting cannot be recommended given the concerns for hypothermia, hyperthermia, sunburn, and long‐term risk of various skin malignancies.

Adjuvant therapies for the prevention and treatment of hyperbilirubinemia either lack strong supportive evidence of efficacy and safety or theoretical considerations suggest more likely harm than benefit and are reviewed extensively in the 2022 AAP Clinical Practice Guideline Revision.¹ 

Phototherapy use over the past 6 decades in newborn infants 35 or more weeks of gestation has been safe, effective, and beneficial to neonatal public health. When performed under medical supervision, no known significant or worrisome risks have been reported. However, concerns about photo-oxidative injury or superficial skin DNA damage have been raised in multiple studies that applied inconsistent light dosing. It has been suggested that phototherapy is associated with a small, statistical risk of subsequent cancer⁶⁶  and epilepsy.⁶⁷  Most of these epidemiologic reports are confounded by inconsistent use of devices and clinical practices, such as use of white light, inadvertent exposure to UV lights, or exposure to unfiltered direct sunlight. UV irradiation may occur with the use of fluorescent light sources for phototherapy, which could have some mutagenic risk, although likely very small and probably inconsequential in most cases. Our knowledge of potential risk of phototherapy comes from its use in extremely preterm neonates and observations from bench studies. The use of blue-green LED devices do not pose this risk but has been associated with some photo-oxidation in exposed tissues.^29,68,69  The exact mechanism(s) by which LED light interacts with tissues to cause any injury is unknown but may be related to the degree of translucency in the skin of extremely preterm infants.^70,71 

Contraindications to the use of phototherapy are rare but include infants with known congenital porphyria or albinism. It may be used with caution among infants who have concurrent cholestasis and exfoliative dermatologic disorders. Phototherapy has no effect in reducing conjugated hyperbilirubinemia, and, if used, may lead to a slow reversible nontoxic bronzing of the skin. This report does not address the use of phototherapy in preterm infants (<32 weeks of gestation). A prudent clinician closely assesses for over-treatment and over prescription. Indeed, the Eunice Kennedy Schriver National Institute of Child Health and Development trial reporting on the use of phototherapy in the most vulnerable preterm infants (birth weight <750 g) suggests a Bayesian increase in mortality.⁷¹  At the time of this writing, another National Institutes of Health-sponsored trial is underway, comparing the use of continuous versus cycled phototherapy to assess the relative safety and efficacy of reducing phototherapy exposure. Although animal model studies are hypothesis-generating, their relevance to humans must be established in rigorous clinical studies that could include population surveillance studies. However, any recently reported associations between phototherapy, cancer risks, and epilepsy need further validation in prospective studies before any changes in current guidelines for clinical practice are warranted.

The AAP Evidence-Based Clinical Practice Guidelines Development and Implementation Manual notes that new data have emerged regarding potential phototherapy-related harms (Table 4), an emerging subject that was not previously covered. The committee has reviewed all relevant literature without a date restriction. Two systematic reviews (initial and expanded) were found to be conducted in accordance with the cited “Preferred Reporting Items for Systematic Reviews and Meta-Analysis Guideline” to ascertain “What are the adverse clinically detectable effects of phototherapy in newborns?” with a comparator of nontreatment for increased risk of any adverse clinical outcome that is important to neonatal patients, their families, and/or the clinicians treating them. In addition, a review search of 45 manuscripts showed that phototherapy is associated with a statistically significant yet low overall risk of causing potential harm. Childhood seizures are one of the most serious, but infrequent, illnesses (adjusted 10-year excess risk of 2.4; 95% confidence interval: 0.6–4.1 per 1000 phototherapy-treated infants) associated with phototherapy used for hyperbilirubinemia. Regardless of this association, the rationale for such concurrence remains unclear thus far. However, this epidemiologic review reported an association but did not offer rationale for cause and effect. The current 2022 AAP Clinical Practice Guideline Revision¹  notes that although the topic is understudied, there is some evidence that phototherapy may limit familial bonding with the newborn infant. In a single observational study, 70% mothers of infants born from 1987 to 1988 who had a diagnosis of jaundice and in whom breastfeeding was terminated were concerned that their infants’ care implied that their infant (<2500 g birth weight) had been moderately to severely ill and their concern remained at 1-month postnatal age after having received phototherapy in the NICU.⁷²  It should be noted that clinical practice (including increased phototherapy utilization) and parental counseling (on phototherapy and breastfeeding) have been individualized and changed over the past 30 years.

Studies were unable to categorically differentiate or distinguish adverse outcomes that could be independently attributed to either the magnitude of hyperbilirubinemia or exposure to phototherapy. Therefore, treatment thresholds should be established that can balance the risk of adverse effects of phototherapy and its possible benefit at reducing TSB concentrations before reaching potential neurotoxic levels. These retrospective studies should also be interpreted by the ongoing evolution, over the past 30 years, of phototherapy devices that no longer incorporate heat-generating lamps and filter UV irradiation to avoid unnecessarily high irradiances.

Many gaps in knowledge remain regarding the use of phototherapy. The following are among the most important:

• A validated cost-effective device that can measure real-time wavelength and irradiance delivered by a phototherapy device is urgently needed to be able to assess the true efficiency of phototherapy in reducing TSB concentrations.

• The safety and efficacy of home phototherapy for specific types of newborn infants at specific TSB thresholds remains a research priority.

• Rigorously designed and appropriately powered studies (such as those evaluating the use of cycled [intermittent] phototherapy) are needed to definitively determine the potential long-term sequelae of phototherapy and of specific durations and magnitudes of both conjugated and unconjugated hyperbilirubinemia and concurrent glucose-6-phosphate dehydrogenase deficiency.

• Design technologies that can continuously measure total photon dose (irradiance delivered to BSA in real time) to identify potential adverse outcomes.⁷³ 

When implemented in a timely manner and performed with standardized procedures, phototherapy is a predominantly safe and noninvasive modality that will minimize risk of neonatal brain injury. Experts consider that the current prescribed thresholds¹  can provide sufficient margin of safety to prevent bilirubin neurotoxicity in newborn infants ≥35 weeks of gestation.

Vinod K. Bhutani, MD, FAAP

Ronald J. Wong, PhD

David Turkewitz, MD, FAAP

Daniel A. Rauch, MD, FAAP

Meredith E. Mowitz, MD, MS, FAAP

Wanda D. Barfield, MD, MPH, FAAP

Eric Eichenwald, MD, FAAP, Chairperson

Namasivayam Ambalavanan, MD, FAAP

Charleta Guillory, MD, FAAP

Mark Hudak, MD, FAAP

David Kaufman, MD, FAAP

Camilia Martin, MD, FAAP

Ashley Lucke, MD, FAAP

Margaret Parker, MD, FAAP

Arun Pramanik, MD, FAAP

Kelly Wade, MD, FAAP

Timothy Jancelewicz, MD, FAAP – AAP Section on Surgery

Michael Narvey, MD – Canadian Pediatric Society

Russell Miller, MD – American College of Obstetricians and Gynecologists

RADM Wanda Barfield, MD, MPH, FAAP – Centers for Disease Control and Prevention

Lisa Grisham, APRN, NNP-BC – National Association of Neonatal Nurses

David K. Stevenson, MD, FAAP

M. Jeffrey Maisels, MD, FAAP

Hendrik J. Vreman

Richard A. Polin, MD, FAAP

Angelo A. Lamola

Cody C. Arnold, MD, FAAP

Finn Ebbesen

Jim Couto, MA

The authors recognize the collective pioneering contributions of scholars, practitioners, scientists, photobiologists, and bilirubin researchers as well as a plethora of clinicians and bioengineers who have contributed to extensive body of literature and evidence for this breakthrough technology that has helped save lives and prevent neonatal brain injury. Thus, it is not a matter of “just turn the lights on” but that of trusting your own knowledge and judgment to assess benefits over risk of any human therapy.

AAP

American Academy of Pediatrics

BSA

body surface area

IR

infrared

LEDs

light-emitting diodes

TSB

total serum/plasma bilirubin

UV

ultraviolet