Menu Expand
Neonatal Hyperbilirubinemia in Preterm Neonates, An Issue of Clinics in Perinatology, E-Book

Neonatal Hyperbilirubinemia in Preterm Neonates, An Issue of Clinics in Perinatology, E-Book

David K. Stevenson | Vinod K. Bhutani

(2016)

Additional Information

Book Details

Abstract

Preterm neonates remain at increased risk for adverse bilirubin-related outcomes, including acute bilirubin encephalopathy relative to term infants. Yet, most vulnerable neonates are likely to benefit from the potent anti-oxidant properties of bilirubin. Evidence-based guidelines for the management of hyperbilirubinemia in preterm infants, however, are lacking. High concentrations of unconjugated bilirubin can cause permanent neurologic damage in infants, evident through magnetic resonance imaging of chronic bilirubin encephalopathy or kernicterus. There is a growing concern that exposures to even moderate concentrations of bilirubin may lead to subtle but permanent neurodevelopmental impairment referred to as bilirubin-induced neurologic dysfunction. Our current use of phototherapy to decrease bilirubin loads and its potential photo-oxidant properties is a biological conundrum that has been questioned in the use of phototherapy for very low birth weight neonates. In this issue of Clinics in Perinatology, we provide updates on the current understanding of the biology, mechanisms of increasing bilirubin load due to hemolysis, decreased bilirubin binding capacity and glucose-6-phosphate dehydrogenase deficiency, as well as clinical strategies to operationalize the thresholds for hyperbilirubinemia interventions in preterm infants.

Table of Contents

Section Title Page Action Price
Front Cover Cover
NeonatalHyperbilirubinemia inPreterm Neonates i
Copyright\r ii
Contributors iii
CONSULTING EDITOR iii
EDITORS iii
AUTHORS iii
Contents vii
Foreword: Why the Premature Brain Is More Prone to Bilirubin-induced Injury\t\r vii
Preface: Preterm Neonates: Beyond the Guidelines for Neonatal Hyperbilirubinemia\r vii
Hyperbilirubinemia in Preterm Neonates\r vii
Hemolysis in Preterm Neonates\r vii
Bilirubin Binding Capacity in the Preterm Neonate\r vii
A Pharmacologic View of Phototherapy\r viii
Biology of Bilirubin Photoisomers\r viii
Phototherapy and the Risk of Photo-Oxidative Injury in Extremely Low Birth Weight Infants\r viii
Bilirubin-Induced Neurotoxicity in the Preterm Neonate \r viii
Bilirubin-Induced Audiologic Injury in Preterm Infants\r ix
The Preterm Infant: A High-Risk Situation for Neonatal Hyperbilirubinemia Due to Glucose-6-Phosphate Dehydrogenase Deficien\r ix
Glucose-6-Phosphate Dehydrogenase Deficiency and the Need for a Novel Treatment to Prevent Kernicterus\r ix
Cholestasis in Preterm Infants\r ix
Development of a Web-Based Decision Support Tool to Operationalize and Optimize Management of Hyperbilirubinemia in Preterm \r x
CME Accreditation Page xi
PROGRAM OBJECTIVE xi
TARGET AUDIENCE xi
LEARNING OBJECTIVES xi
ACCREDITATION xi
DISCLOSURE OF CONFLICTS OF INTEREST xi
UNAPPROVED/OFF-LABEL USE DISCLOSURE xi
TO ENROLL xi
METHOD OF PARTICIPATION xi
CME INQUIRIES/SPECIAL NEEDS xii
Foreword:\rWhy the Premature Brain Is More Prone to Bilirubin-induced Injury xv
REFERENCES xvi
Preface:\rPreterm Neonates: Beyond the Guidelines for Neonatal Hyperbilirubinemia xvii
REFERENCES xviii
Hyperbilirubinemia in Preterm Neonates 215
Key points 215
INTRODUCTION 215
NATURAL BILIRUBIN PROFILE IN PRETERM NEONATES 217
Prevalence and Incidence 217
Bilirubin Burden 218
CLINICAL PROFILE OF SUBTLE POSTICTERIC SEQUELAE 219
Auditory Dysfunction 219
Visuocortical Dysfunction 220
Integrity of Brainstem Function and Structure 220
BENEFICIAL ROLE OF BILIRUBIN 221
BENCH EVIDENCE OF BILIRUBIN NEUROTOXICITY IN PRETERM NEONATES 221
MARGINS OF CLINICAL SAFETY 222
CLINICAL CARE STRATEGIES 223
Timing of Interventions to Reduce Excessive Bilirubin Load 223
Triage for a Jaundiced Preterm Newborn with Suspicious Clinical Neurologic Signs 224
Emergency Interventions for Rapid Reduction of Bilirubin Concentrations 224
Albumin Infusion 226
Intravenous Gamma Immunoglobulin 226
Phenobarbital 226
Metalloporphyrins 226
FOLLOW-UP OF PRETERM INFANTS AT RISK FOR BILIRUBIN-INDUCED NEUROLOGIC DYSFUNCTION 227
SUMMARY 227
REFERENCES 228
Hemolysis in Preterm Neonates 233
Key points 233
WHAT IS HEMOLYSIS? 233
HOW IS HEMOLYSIS RECOGNIZED IN A JAUNDICED PRETERM INFANT? 234
WHAT IS THE RISK TO A PRETERM INFANT IN WHOM A DONOR RED BLOOD CELL TRANSFUSION WILL RESULT IN A RISE IN TOTAL SERUM/PLASMA ... 235
AFTER IDENTIFICATION OF HEMOLYSIS IN A JAUNDICED PRETERM INFANT, HOW IS EXACT CAUSE FOUND? 238
SUMMARY 239
REFERENCES 239
Bilirubin Binding Capacity in the Preterm Neonate 241
Key points 241
INTRODUCTION 241
Bilirubin–Albumin Biochemical Structure and Binding 242
Bilirubin–Albumin Binding Capacity and Affinity 242
Bilirubin–Albumin Binding as a Function of Gestational Age and Postnatal Age 244
Clinical Risk Factors and Bilirubin–Albumin Binding 244
Phototherapy and Bilirubin–Albumin Binding 245
Exogenous Drugs and Bilirubin–Albumin Binding 245
Intralipid and Bilirubin–Albumin Binding 246
Bilirubin:Albumin Molar Ratio and Risk for Bilirubin-Induced Neurotoxicity 247
Bilirubin–Albumin Binding and Neurodevelopmental Outcomes in Premature Infants 248
SUMMARY 251
REFERENCES 252
A Pharmacologic View of Phototherapy 259
Key points 259
INTRODUCTION 259
Light, Photons, Light Absorption, and Photochemistry: Photons as Drug Units 260
Management of Unconjugated Neonatal Hyperbilirubinemia: Indications for Phototherapy 262
Body burden of bilirubin 262
Bilirubin/albumin binding status 262
Measures of phototherapy efficacy 263
Optical Properties of Neonatal Skin: Action Spectrum and Hematocrit Dependence of Phototherapy 263
Skin optics 263
Action spectrum 264
Hematocrit dependence 265
Bilirubin: Structure, Properties, and Photochemistry 266
4Z,15Z-bilirubin 266
Configurational isomers (E isomers) 266
Lumirubin 268
Photo-oxidation products 268
Excretion Rates of Photoproducts: Relative Roles in Phototherapy 268
Z,E-bilirubin excretion 268
Lumirubin excretion 269
Configurational versus structural isomerization 269
Other Factors in the Optimization of Phototherapy 270
Is there a limiting irradiance for phototherapy? 270
Continuous versus cycled (intermittent) phototherapy 270
Is the production of photoproducts beneficial without excretion? 271
High-risk, very low gestational age, and low body weight infants 271
Oxidative stress 272
Optimum phototherapy light source 272
RESEARCH GAPS 273
REFERENCES 274
Biology of Bilirubin Photoisomers 277
Key points 277
INTRODUCTION 277
BILIRUBIN TOXICITY 278
TYPES OF BILIRUBIN PHOTOPRODUCTS 279
BINDING OF BILIRUBIN ISOMERS 279
IN VIVO MODELS OF MEMBRANE PASSAGE 280
IN VITRO TOXICITY STUDIES 282
CLINICAL IMPLICATIONS 285
SUMMARY 285
REFERENCES 287
Phototherapy and the Risk of Photo-Oxidative Injury in Extremely Low Birth Weight Infants 291
Key points 291
INTRODUCTION 291
PHOTOTHERAPY USE IN EXTREMELY LOW BIRTH WEIGHT INFANTS 292
VULNERABILITY OF EXTREMELY LOW BIRTH WEIGHT INFANTS 292
SUMMARY/DISCUSSION 294
REFERENCES 294
Bilirubin-Induced Neurotoxicity in the Preterm Neonate 297
Key points 297
INTRODUCTION 297
NEUROPATHOLOGY OF KERNICTERUS 298
NEUROIMAGING OF KERNICTERUS 298
MOLECULAR AND CELLULAR MECHANISMS OF BILIRUBIN NEUROTOXICITY 299
Bilirubin and Membranes 299
Excitotoxicity 299
Neuroinflammation 301
Oxidative Stress 302
Bilirubin and Intracellular Calcium Homeostasis 302
Perturbed Cell Cycle Kinetics, Cell Cycle Arrest, Altered Neurogenesis 302
Central Nervous System Immaturity 303
Future Basic Research Efforts 304
Clinical Manifestations of Bilirubin-Induced Central Nervous System Injury in the Preterm Neonate 304
Acute bilirubin encephalopathy 304
Chronic bilirubin encephalopathy 305
Auditory-predominant kernicterus 305
Low-Bilirubin Kernicterus 305
Hypoalbuminemia 307
Subtle kernicterus (bilirubin-induced neurologic dysfunction) 307
REFERENCES 308
Bilirubin-Induced Audiologic Injury in Preterm Infants 313
Key points 313
INTRODUCTION 313
MECHANISMS OF BILIRUBIN-INDUCED NEUROLOGIC DAMAGE 314
PRETERM INFANTS ARE PARTICULARLY VULNERABLE TO BILIRUBIN-INDUCED NEUROLOGIC DAMAGE 315
BILIRUBIN-INDUCED NEUROLOGIC DAMAGE AND THE AUDITORY BRAINSTEM RESPONSE 315
AUDITORY NEUROPATHY SPECTRUM DISORDER 316
SPEECH AND LANGUAGE DISORDERS 316
THE UTILITY OF TOTAL SERUM/PLASMA BILIRUBIN LEVELS IN SCREENING FOR BILIRUBIN-INDUCED NEUROLOGIC DAMAGE 317
BENEFITS AND DRAWBACKS OF NEWBORN HEARING SCREENING 317
IS BILIRUBIN-INDUCED NEUROLOGIC DAMAGE AUDITORY DAMAGE REVERSIBLE? 318
SUMMARY 318
REFERENCES 319
The Preterm Infant 325
Key points 325
INTRODUCTION 326
Glucose-6-Phosphate Dehydrogenase Deficiency and Prematurity as Coexisting Risk Factors for Neonatal Hyperbilirubinemia 326
Glucose-6-phosphate dehydrogenase deficiency: the scope of the problem 326
Medical complications associated with glucose-6-phosphate dehydrogenase deficiency 326
Favism and acute hemolytic episodes 326
Extreme neonatal hyperbilirubinemia 327
Moderate neonatal hyperbilirubinemia 327
Prematurity: added risk for neonatal hyperbilirubinemia 327
Glucose-6-phosphate dehydrogenase deficiency and prematurity: a synergistic, potentially dangerous, combination 328
Glucose-6-phosphate dehydrogenase deficiency, prematurity, and uridine diphosphate-glucuronosyltransferase 1A1 (TA)7 gene p ... 328
IMBALANCE BETWEEN BILIRUBIN PRODUCTION AND ELIMINATION: THE BASIS OF NEONATAL HYPERBILIRUBINEMIA 329
Imbalance Between Bilirubin Production and Conjugation Demonstrated Mathematically 329
Production-conjugation index in glucose-6-phosphate dehydrogenase-normal newborns 329
The production-conjugation index in glucose-6-phosphate dehydrogenase-deficient neonates 329
The greater risk of glucose-6-phosphate dehydrogenase-deficient premature newborns demonstrated mathematically 330
CLINICAL REPORTS OF HYPERBILIRUBINEMIA IN GLUCOSE-6-PHOSPHATE DEHYDROGENASE-DEFICIENT PRETERM NEWBORNS 330
Clinical Series 330
Case Reports 331
DIAGNOSIS OF GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENCY IN PREMATURE INFANTS 333
Glucose-6-Phosphate Dehydrogenase-Adequate Premature Infants 333
Glucose-6-Phosphate Dehydrogenase-Deficient Premature Infants 334
PREVENTION AND TREATMENT OF HYPERBILIRUBINEMIA IN PRETERM, GLUCOSE-6-PHOSPHATE DEHYDROGENASE-DEFICIENT NEWBORNS 334
Prevention 334
Treatment 334
Extreme hyperbilirubinemia 334
Moderate hyperbilirubinemia 334
Neonatal Screening for Glucose-6-Phosphate Dehydrogenase Deficiency 334
PRETERM INFANTS REQUIRING BLOOD OR EXCHANGE TRANSFUSION 335
Should Preterm Infants Receive Only Glucose-6-Phosphate Dehydrogenase-Normal Blood? 336
SUMMARY AND BEST PRACTICES 336
REFERENCES 336
Glucose-6-Phosphate Dehydrogenase Deficiency and the Need for a Novel Treatment to Prevent Kernicterus 341
Key points 341
INTRODUCTION 341
HYPERBILIRUBINEMIA AND KERNICTERUS 342
GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENCY 342
GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENCY INCREASES THE RISK OF NEONATAL HYPERBILIRUBINEMIA AND KERNICTERUS 343
HOW DOES GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENCY CONTRIBUTE TO KERNICTERUS? 343
HOW TO PREVENT KERNICTERUS? 346
Strategies to Reduce Total Bilirubin Levels 347
Treatment with Antioxidants 347
Restoring Endogenous Glutathione: Activating Glucose-6-Phosphate Dehydrogenase 347
REFERENCES 350
Cholestasis in Preterm Infants 355
Key points 355
INTRODUCTION 355
INCIDENCE 356
ETIOLOGY AND PATHOPHYSIOLOGY 356
Anatomic and Functional Immaturity 356
Parenteral Nutrition 357
Intestinal Injury 357
Sepsis 358
Medications 359
Other Specific Diseases 359
CLINICAL EVALUATION 361
Laboratory 361
Radiologic 363
Liver Biopsy 363
MANAGEMENT 363
Medical 363
Ursodeoxycholic acid 363
Cholecystokinin 364
Erythromycin 364
Nutritional 364
Enteral nutrition 364
Cycling parenteral nutrition 364
Lipid dose reduction 365
Alternative parenteral lipids 365
Enteral fish oil 365
Vitamin E 366
Catheter Locks 366
Multidisciplinary Rehabilitation 366
Organ Transplantation 367
SUMMARY AND DISCUSSION 368
REFERENCES 368
Development of a Web-Based Decision Support Tool to Operationalize and Optimize Management of Hyperbilirubinemia in Preterm ... 375
Key points 375
INTRODUCTION 375
DEVELOPMENT OF THE CLINICAL DECISION SUPPORT TOOL 376
Operationalizing Consensus-Based Recommendations 376
The Clinical Decision Support Tool: “Premie BiliRecs” 377
Process for Electronic Medical Record Integration 378
Limitations 381
GENERATION OF NEW KNOWLEDGE 381
SUMMARY 382
ACKNOWLEDGMENTS 382
REFERENCES 382
Index 385