Calorie intake in sick versus respiratory stable very low birthweight babies

A comparison between the calorie intake and energy source of sick versus respiratory stable very low birthweight (VLBW, less than 1500 g) babies was made to ascertain the time taken for them to achieve adequate daily calorie intake. It was an observational study of 23 consecutive VLBW babies in which sick respiratory unstable babies were defined as those who required ventilation beyond 72 h of life. Data were collected on the daily fluid and calorie intake for 30 days of life, and beyond if necessary until the babies achieved full enteral feeding and calorie intake of more than 100 kcal/kg per day. Growth parameters at the time of transfer or discharge were also analyzed. In the study, there were 14 sick VLBW and 9 respiratory stable babies with a mean birthweight of 1027 g and 1212 g, respectively. Their mean gestational age (28.7 weeks vs 31.2 weeks), mean age when calorie intake of 100 kcal/kg per day was achieved (19.8 days vs 7.0 days), mean duration of parenteral nutrition (17.1 days vs 2.7 days), mean age when enteral feeds commenced (8.9 days vs 1.7 days) and mean age when full enteral feeding was established (20.6 days vs 7.3 days) were statistically different for the two groups. For the respiratory unstable babies, parenteral nutrition provided more energy than milk until 15 days of life. The average daily energy intake of 100 kcal/kg per day was only achieved by 30 days of life in this group. In the respiratory stable group, milk provided more than 100 kcal/kg per day from 10 days of life. There were no significant differences in somatic growth with regard to bodyweight, length and head circumference for these two groups of babies at the time of transfer or discharge. The daily calorie intake of sick VLBW babies was suboptimal even with the use of parenteral nutrition. The respiratory stable babies, through enteral feeding, easily achieved the recommended daily calorie intake.