Neonatal Jaundice
Q. 1. What constitutes exactly the abnormal persistence of jaundice in newborn? Nelson Textook of Pediatrics considers persistence of jaundice more than 2 weeks as abnormal- [It, has not been specified if it is a Clinical jaundice only or any raised serum bilirubin] while Manual of Cloherty considers persistence as 8 days in a term infant and after 14 days in a premature infant on one hand. The latter also comments that a level under 2 mg/ dl may not be seen until One month of age in both term and premature infants.
In a healthy term baby, not having evidence of hemolysis, what should be our approach? Is it essential to stop breastfeeding to establish a diagnosis of breastmilk jaundice, even if serum bilirubin level is not very high, in order to rule out possibility of serious disorders such as galactosemia, hypothyroidism, pyloric stenosis, etc.?
A.. 1. No firm rules can be framed to define abnormal persistence of Jaundice in a new- born. A careful review of the maternal and infant history and thorough Clinical examination
of the infant will guide proper management.
By far the most frequent cause of non- hemolytic Clinical jaundice beyond first week of life is breastmilk jaundice. In a term healthy newborn on breastmilk with elevated unconjugated bilirubin upto
15 mg/dl after first week of life no investigations are required. The mother needs to be reassured and baby can be followed up from home. With continuation of frequent breastfeeding, icterus will disappear over next 7 to 10 days and in majority by 4 weeks of age (rarely it may persist upto 8 to 12 weeks). It is unusual, that conditioJ1s like galactosemia, pyloric stenosis or sepsis will have jaundice as the sole manifestation of underlying disease.
For those babies with bilirubin values more than 15 mg/dl, one may decide to consider-stopping breastmilk temporarily for 48 hours. This will be followed by a dramatic fall of bilirubin in most cases of breastmilk jaundice. Patients not showing bilirubin decline will need further evaluation for finding out the cause. Often prematurity or ongoing hemolysis may lead to abnormal persistence of jaundice. A report of dark mine or light stools should prompt one to investigate for conjugated hyperbilirubinemia which may be due to a serious underlying condition(1).
Q.2. Blue or green light (425-475 nm wave-length) is said to be superior for phototherapy. However, blue light makes the child appear cyanotic. It is difficult to detect pallor or cyanosis associated with apnea or convulsion and thus resort to accurate clinical monitoring for apnea in premature babies kept under blue light. In our country, most manufacturers use blue PVC sheet in front of white tube lights to construct the light phototherapy. This decreases effective irradiance reaching to baby skin thus diminishing efficacy of phototherapy. Keeping these points in mind, what should be practical guidelines in our setup? What should be the number of tube lights for effective phototherapy?
A. 2. Phototherapy is an accepted method of
treating neonatal jaundice. The most effective lights for phototherapy are those with high-energy output near the maximum ad- sorption peak of bilirubin (450 to 460 nm). Special blue lamps with a peak output at 425 to 475 nm are the most efficient for phototherapy and these do not emit harmful ultravoilet (UV) rays(2). Blue-green light may interfere with the monitoring of cyanosis. In addition, blue light causes nausea, giddiness and headache to the staff working in NICU. Green light cause erythema and subsequent tanning of skin. A combination of alternating two blue and two white tubelights (20 W each) are sufficient to provide adequate irradiance of 4 to 8 micro- watt/cm2/nm in the wavelength range of 425- 475 nm. To increase the irradiance to 10-12 microwatt/cm2/nm a combination of four blue and two white tubes have to be used. The irradiance can be. measured by bilimeter or fluxmeter.
Cool daylight lamps (fluorescent tube- lights 6 to 8, .20 W each) with a principal peak at 550 to 600 nm and a range of 380 to 700 nm are most. commonly used in phototherapy units in our country. These . units provide 4-5 microwatt/cm2/nm in the wavelength range .of 425-475 nm, when the fluorescent tubes are new. With usage the irradiance
is bound to be much lower than required for therapeutic purposes. These
units are effective in the treatment of non- hemolytic jaundice in term
and preterm neonates. Occasionally these are not effective especially in cases of severe or rapidly increasing neonatal jaundice(3,4). Remember the lamps should be changed every 3 months or earlier if irradiance is being monitored. Put- ting a blue plastic perspex or glass sheet in front of white lamps will not increase irradiance of unit in bluegreen range,
but rather decrease it.
Halogen white light (150 W, 20 V) having significant output in blue spectrum is useful for infants under radiant warmers. Aperture size (3-20 inch) and unit to mattress . distance can be controlled. Inner reflecting surface lining of halogen bulb asborbs
majority of infared (IR) rays (a fan continuously cools it) and a UV filter in front of bulb blocks harmful UV rays from reaching the baby. Indigenous halogen bulb phototherapy units may lack UV filter and thus may not be safe for use. A few warmers which have side mounted halogen bulbs (50 W, three on each side) without UV and IR
filters work like an uncontroled thermal therapy unit rather than
safe phototherqpy.
The most recent is a fiber-optic light system that delivers light from it high-intensity lamp to a fiber-optic pad or blanket. There are two devices currently in the market.: the Wallaby phototherapy system (Fiberopic Medical Products Inc., Allentown, P A) and the -BiliBlanket phototherapy system (Ohmeda, Columbia, MD). In the Wallaby system, illumination is transmitted from a halogen lamp source to a bundle of fiber-op- tic fibers contained in a cummerbund which
can be wrapped around the
baby.
Alternatively the infant can lie on the blanket. In the Ohmeda system the baby lies on a woven fiber-optic mat. The mat may also be tucked under the shirt while the
baby
is held. These systems have obvious advantages over conventional phototherapy systems
-
eye patching is probably unnecessary which eliminates the possibility of nasal obstruction from eye- pads; the light is devoid of infrared rays- hence cold light does not warm the baby; the equipment is less bulky than conventional phototherapy equipment and. babies can be held and nursed while they receive phototherapy. This is also a convenient way of delivering double phototherapy when it is necessary to reduce the bilirubin level as rapidly as possible.
It is a mistake to assume that just because a phototherapy unit is emitting
fluorescent light when it is switched on, it is necessarily providing treatment for the jaundiced baby. However, it is imperative that one must periodically check irradiance of phototherapy units used for treating pathological
jaundice. Phototherapy used for treating pathological jaundice is
like giving a drug. One is not justified in using substandard light sources for treatment of neonatal jaundice.
Use Philips 20 W, 2ft blue fluorescent tubes TL-52 for phototherapy units costing Rs. 700-900/- each. Don't use TL-02, TL-03, TL-03, TL-05 Philips blue fluorescent tubes. These are cheaper cost (Rs. 250/- each) and produce harmful UV rays used for sterilization, attracting insects for killing or dermotherapy for vitiligo. Imported 20W tubes for treatment of jaundice come with following specifications: F20TI2/B-Regular blue; F20TI2/BB-Special high output; 20SBW-NU-Blue white light; and 20SBG- NU-Blue green light.
Q. 3. Is there any role of putting baby under sun in cases with mild jaundice?
A. 3. Mild or minimal icterus, does not need any treatment. Sunlight is relatively ineffective
because of low blue content of light. Besides, hyperpyrexia and skin burns .occur in prolonged sunlight exposure.
Questions by:
Ramesh K. Agarwal, 151. Street No.7.
Barkat Nagar.
Jaipur 302015. India.
Reply by:
Ashok K. Deorari,
Additional Professor,
Division of Neonatology,
Department of Pediatrics.
All India Institute of Medical Sciences,
New Delhi 110 029, India.
1.
Recommendations of American Academy of Pediatrics. Practice parameter: Management of hyperbilirubinemia in the healthy term newborn. Pediatrics 1994; 94: 558-562.
2.
Ennever JF. Blue light, green light, white light, more light: Treatment of neonatal jaundice. Clin Perinatol 1990; 17: 407-478.
3.
Tan KL Efficacy of tluouescent day light blue and green lamps in the management of non-hemolytic hyperbilirubinemia. J Pediatr 1989; 14: 132-137.
4.
Tan KL, Lim GC, Boey KW. Efficacy of "high-intensity" blue-light and "standard day- light" phototherapy for non-hemolytic hyperbilirubinemia. Acta Pediatr 1992; 81: 870-874.
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