Aims To investigate the effects of late versus early cord clamping on systemic circulation and cerebral blood flow velocity in premature infants <1500 g (very low birth weight).

Subjects 34 neonates were studied 4 h after caesarean section. In 18 neonates (birth weight 1240 ± 290 g; gestational age 30.0 ± 2 weeks) the umbilical cords were clamped after 30 s and the infants were placed 30 cm below placenta level (late CC), and in 16 (1231 ± 350 g; 28.6 ± 2 weeks) the cords were clamped immediately (early CC). Volume expansion (serum or plasma) were given to keep the mean blood pressure (MBP) >30 mm Hg.

Methods MBP (mm Hg), left ventricular output (LVO, ml/kg per minute), mean cerebral blood flow velocity in the arteria carotis interna (ACI, m/s; Doppler ultrasound), haemoglobin (g/dl), and haematocrit (%) were measured. Systemic and cerebral haemoglobin transport (HbT), and systemic vascular resistance (SVR; mm Hg/kg per minute) were estimated. Statistics: Unpaired* t test.

Results (4 h after birth). Parameter: early CC versus late CC, *p value. MBP 36 ± 4 versus 44 ± 7, p = 0.03; LVO 241 ± 38 versus 245 ± 25, NS; ACI 0.16 ± 0.03 versus 0.20 ± 0.05, NS; SVR 123 ± 40 versus 145 ± 30, p = 0.05; haematocrit 0.46 ± 0.4 versus 0.55 ± 0.5, p = 0.02; cerebral HbT 7.4 ± 1.8 versus 11.1 ± 4.1, p = 0.04; systemic HbT 154 ± 27 versus 181 ± 24, p = 0.05.

Conclusions Late cord clamping improves MBP, SVR, haemoglobin, systemic and cerebral HbT in prematures <1500 g. The early cord clamped group required more volume expansion in the first 24 h (early 12/16, 14 ± 7 ml/kg; late 4/18, 5 ± 4 ml/kg; p<0.03).