The Extremely Low Birth Weight (ELBW) (<1000 grams) neonate challenges not only medical issues, but also raises ethical questions that have impact on the patient, parents, medical personnel and society.
Mortality and Morbidity
Survival and complications of the ELBW neonates at the Neonatal Intensive Care Unit (NICU) of the Rocky Mountain Hospital for Children (RMHC) at Presbyterian/St. Luke’s Medical Center are tracked by the Vermont Oxford Network (VON), a non-profit voluntary collaboration of over 700 NICUs.
VON Mortality Data (2007): Birth Weight (grams)
|RMHC NICU %|
Mortality and morbidity rates (Tables 1 and 2) are inversely related to birth weight. One half of patients with birth weights between 501-600 grams will succumb. Those who survive, have significant morbidities.
The morbidity data indicate that even in the 901-1000 gram neonates, two thirds have significant complications. Overall complications are detailed in Table 3.
Other poor prognostic factors include intrauterine growth retardation, multiple gestation pregnancies, in vitro fertilization, male neonates, and chorioamnionitis.
Those morbidities with the greatest impact on quality of survival are severe IVH, PVL, severe ROP and NEC. All require long-term therapy. PVL (cysts formed by the softening of the periventricular white matter) is strongly correlated with deficits of cognition, motor skills, speech and overall development. Fortunately, patients with severe ROP can be successfully treated by laser therapy, diminishing the loss of complete vision.
VON Morbidity Data (2007): Birth Weight (grams)
|RMHC NICU %|
|Respiratory distress syndrome (RDS)||90|
|Chronic lung disease (CLD)||60|
|Persistent ductus arteriosus (PDA)||49|
|Any retinopathy of prematurity (ROP)||40|
|Any intraventricular hemorrhage (IVH)||22|
|Nosocomial bacterial infection||22|
|Coagulase negative staphylococcus infection||18|
|Necrotizing enterocolitis (NEC)||9.7|
|Cystic periventricular leukomalacia (PVL)||5.6|
To Resuscitate or Not to Resuscitate, That is the Question
The decision to initiate resuscitation is most complex as it involves the ability to accurately determine gestational age1, survival chances, morbidity suffered, long term results, and medical and parental attitudes.
Gestational ages (GA) of assisted pregnancies are the most precise. Sonography varies +/- 5 days. Except for the finding of translucent skin indicating <24 weeks, physical examination is difficult and complicated by the variability of individual growth and maturation. According to the American College of Obstetrics and Gynecology2, <21 weeks GA has no survivors; <24 weeks GA survival is unlikely and then neurologically damaged; 25 weeks GA (700-800 grams) has a 75% survival rate.
Medical and parental attitudes also affect outcome. Morse and Carlo3 surveyed 362 pediatricians and 379 obstetricians and found those overestimating survival were more likely to offer aggressive therapy, while those underestimating survival withheld aggressive intervention.
Streiner4 polled 169 parents, 93 neonatologists, and 93 NICU nurses and as would be expected, parents were more inclined to save ELBW neonates regardless of age or condition.
Long-term outcome of ELBW neonates by Hack and Fanaroff5, Anderson6, and Wolke7 show growth retardation, increased medical and surgical interventions, decreased intellectual functions (both cognitive and educational), and emotional deficits. From 2000 to 2007, Hack8 reported an improvement in survival of ELBW neonates from 49% to 68% with decreases of cerebral palsy from 13% to 5% and neuro-developmental impairment from 35% to 23%.
As reflected in the publications by Meadows and Lantos9 and Seri and Evans10, the concept of the quality of life and the ethical consideration of when to withhold resuscitation are dilemmas that challenge medical personnel, parents and society in general. For ELBW neonates between 23 (0/7) and 24 (6/7) weeks gestation with birth weights between 500 and 599 grams, their outcomes are exceedingly uncertain.
In this “gray zone” of viability, the ultimate decision of medical intervention must take into consideration the clinical condition, response to therapy, parental involvement in decision making, and the neonatologist’s personal judgment. For healthcare professionals, Meadow and Lantos11 found that the common source of moral distress was not money, resources, or even litigation issues, but rather guilt over long-term implications for families when a neurologically devastated neonate survives.
Most neurologically impaired NICU survivors and their families judged their quality of life acceptable. Physicians and nurses were harder on themselves than need be.
Written by Jeffrey Hanson, MD, Neonatologist, Pediatrix Medical Group
1. Blackmon LR: Biologic Limits of Viability: Implications for Clinical Decision-making. Neoreviews 2003 4:e140-e146.
2. American College of Obstetrics and Gynecology: Perinatal care at the threshold of viability. ACOG practice bulletin (2002) Number 38.
3. Morse SB et al.: Estimation of Neonatal Outcome and Perinatal Therapy Use. Pediatr (2000) 105:1046-1050.
4. Streiner DL, et al.: Attitudes of Parents and Health Care Professionals Toward Active Treatment of Extremely Premature Infants. Pediatr (2001) 108:152-157.
5. Hack M, et al.: Growth of Very Low Birth Weight Infants to Age 20 Years. Pediatrics (2003) 112:e30-e38.
6. Anderson PJ, Doyle LW: Cognitive and educational deficits in children born extremely preterm. Semin Perinatol (2008) 32:51-8.
7. Wolke D et al.: Specific language difficulties and school achievement in children born at 25 weeks of gestation or less. J Pediatr (2008) 152:256–262.
8. Wilson-Costello D, et al: Improved Neurodevelopmental Outcomes for Extremely Low Birth Weight Infants in 2000–2002. Pediatr (2007) 119:37-45.
9. Meadows W, Lantos J: Ethics at the Limit of Viability: A Premie’s Progress. NeoReviews (2003) 4:e157.
10. Seri I, Evans,J: Limits of viability: definition of the gray zone. J Perinatol (2008) Suppl 1:S4-8.
11. Meadows W, Lantos J: Moral reflections on neonatal intensive care. Pediatr (2009) 123:595-597.