All issues > Volume 46(12); 2003

Original Article

J Korean Pediatr Soc. 2003;46(12):1194-1199. Published online December 15, 2003.

Change in the Limit of Viability of Fetal Infants

Chang Won CW Choi¹, Jong Hee JH Hwang¹, Jae Won JW Shim², Sung Sin SS Kim³, Sun Young SY Ko⁴, Eun Kyung EK Lee⁴, Yun Sil YS Chang², Won Soon WS Park²

¹Department of Pediatrics, Samsung Medical Center, College of Medicine, Sungkyunkwan University, Seoul, Korea
²Department of Pediatrics, Kangbuk Samsung Hospital, College of Medicine, Sungkyunkwan University, Seoul, Korea
³Department of Pediatrics, Puchon Hospital, College of Medicine, Soon Chun Hyang University, Puchon, Korea
⁴Department of Pediatrics, Samsung Cheil Hospital, College of Medicine, Sungkyunkwan University, Seoul, Korea

Correspondence Won Soon WS Park ,Email: wspark@smc.samsung.co.kr

Abstract

Purpose
: To determine the change in the limit of viability in fetal infants and the incidence of major complications in neonatal intensive care unit(NICU) at Samsung Medical Center(SMC).
Methods
: Sevety-three infants weighing less than 800 g at birth and 117 infants born earlier than 27 weeks gestational age, who were admitted to NICU at SMC between November 1994 and December 2002, were enrolled. Their medical records were reviewed with a focus on the survival and major complications, including chronic lung disease, retinopathy of prematurity, intraventricular hemorrhage, and periventricular leukomalacia. The limit of viability in fetal infants was defined as the birth weight or gestational age at which a 50% survival rate is reached and the incidence of major complications were compared by period(period I : Nov. 1994-Dec. 1998, period II : Jan. 1999-Dec. 2002).
Results
: The limit of viability in fetal infants was markedly lowered from birth weight range of 800-900 g or gestational age range of 26＋0-26＋6 weeks in period I to birth weight range of 600-700 g or gestational age range of 24＋0-24＋6 weeks in period II. The incidence rates of major complications at the limit of viability were all less than 50% in period II. There was no definite trend toward increased incidence of major complications as birth weight get smaller and gestational age get younger.
Conclusion
: Our results indicate that at present, fetal infants whose body weight is over 600 g, or whose gestational age is over 24 weeks should be resuscitated vigorously. The risk of major complications at this birth weight or gestational age seems to be not greater than that at a bigger birth weight or an older gestational age.

Keywords :Viability, Survival rate, Fetal infants, Limit