Survival of very low birth and extreme low birth weight infants at Mankweng Neonatal Care Unit

Abstract

Objectives To determine the prevalence and survival rate; and to assess the maternal risk factors as well as complications of prematurity, associated with the mortality of very low and extremely low birth weight infants in the Neonatal Intensive Care Unit (NICU) of Mankweng Hospital.

Materials and Methods

A retrospective descriptive study was conducted at the NICU of Mankweng Hospital for a 7-month period from 1st January to 31st July 2015. The patient medical records and the Perinatal Problem Identification Programme (PPIP) data were used for the study.

Results

Prevalence of prematurity was 23%, Infants weighing between 500g-1499g represented 6.3% of the total live births and 25% of the admissions to the NICU; of which 4.9% were classified as extremely low birth weight (ELBW). Overall 77% of the study population survived until discharge. From the medical records, the survival to discharge of infants with weight 500g - 999g was 52%; and 84% for those with weight 1000g-1499g. Multivariable analysis found that improved survival was associated with an increase in gestational age (p <0.001), as well as birth weight (p <0.001) and prolonged length of stay. Variables associated with poor survival were spontaneous preterm labour (p = 0.031), low Apgar score at 1 and 5 minutes (p <0.001), sepsis (p = 0.001), respiratory distress syndrome (p <0.001), pulmonary hemorrhage (p <0.001), hypothermia (P = 0.005), resuscitation at birth (p = 0.002) and necrotising enterocolitis (p =0.044). Antenatal steroids were not associated with survival (p =0.111), however this was not documented in 53%(134/252) of the records, so the non-significance to outcome in this study may not be a true reflection. The use of NCPAP or SiPAP only was associated with improved survival of up to 69% and high mortality rates were recorded in babies who required invasive ventilator support. Multi-organ immaturity was found to be the most common cause of death, followed by sepsis. Conclusion: The prevalence and survival rates of very low and extremely low birth weight, found in this study are comparable to those found in other tertiary hospitals in South Africa. The survival rate of ELBW babies is low and must be improved. Reliable data and further research should address effective steps to prevent preterm labour, extreme prematurity and hypothermia. The documentation and provision of antenatal steroids is encouraged.

KEY CONCEPTS: Prematurity, Extremely low and Very low birth weight, Risk factors, Prevalence, Survival, Neonatal mortality rate.