Inappropriate fluid response in congenital diaphragmatic hernia: first report of a frequent occurrence

Safe management of the newborn infant with congenital diaphragmatic hernia (CDH) requires precise fluid administration to avoid hypovolemia or fluid overload. Twenty-two CDH patients and 12 infants who underwent abdominal operations were studied for three postoperative days to determine whether the postoperative neonatal renal response to fluid administration was appropriate or inappropriate. Each response was categorized, on the basis of urine and blood measurements, as: (1) appropriate urine output and concentration, (2) inappropriate urine output and concentration with fluid retention or (3) renal failure. Fluid intake was similar in all groups. The CDH group had a significantly lower urine output, higher urine osmolarity, and lower serum osmolarity. All of the control group (100%) responded appropriately to intake. Sixty-four percent of the CDH group inappropriately retained water during the first 16 hours (appropriate, 27%; renal failure, 9%). By 24 hours, 34% still had inappropriate urine output and fluid retention. The majority of patients with CDH initially responded inappropriately to postoperative fluid intake. If this response is not recognized and fluid intake is not adjusted, serious fluid overload will result.