Failure of phototherapy to reduce serum bilirubin in newborn infants

Increased osmotic fragility of erythrocytes in chronically jaundiced rats after phototherapy

Littermate homozygous (jj) and heterozygous (Jj) Gunn rats, were irradiated with blue fluorescent light for 18 hours continuously. The incident irradiance was 1.5 mWatts/cm2 in the 420--480 nm band pass. The influence of the irradiance on circulating erthrocytes was studied by testing their osmotic fragility before and after the irradiance. The non-jaundiced, Jj, animals did not exhibit any increase in the osmotic fragility of their erythrocytes. The osmotic fragility of the erythrocytes from jaundiced, jj, animals was the same as the Jj animals prior irradiance. However, the fragility of the erythrocytes from the jj animals was significantly increased after the 18 hours of irradiance. The results indicated that the photodynamic action of bilirubin may be present in vivo.

Intermediate phototherapy in the treatment of jaundice in the premature infant

A controlled trial of the use of intermittent phototherapy for the treatment of hyperbilirubinemia in newborn infants is reported. Periods of illumination of (1) 15 minutes light on, 15 minutes light off, (2) 15 minutes on, 30 minutes off, and (3) 15 minutes on, 60 minutes off are as effective as is continuous illumunation. A comparison with previous trials of intermittent phototherapy is made and differences in results are explained using as a model the action of light on bilirubin.

Comparison of the effectiveness of phototherapy and exchange transfusion in the management of nonhemolytic neonatal hyperbilirubinemia

The relative effectiveness of phototherapy and exchange transfusion for nonhemolytic neonatal hyperbilirubinemia was compared in two closely matched groups of infants. Although the exchange transfusion achieved an immediate reduction of bilirubin level, the "rebound" was rapid and tended to offset this reduction. The more gradual and steady effect of phototherapy resulted in a significantly lower serum bilirubin level at 1, 2, and 3 days after commencement of therapy; the rebound after phototherapy was small. Phototherapy was demonstrated to be more effective than exchange transfusion in achieving prolonged reduction of bilirubin levels for nonhemolytic hyperbilirubinemia. With more efficient lamps delivering more energy in the desired spectrum, it would seem feasible to treat hyperbilirubinemia of whatever etiology with this safer and more convenient form of therapy, though sometimes only as in adjunct therapy.