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Updated: Jun 1, 2026
Transcutaneous Microcirculatory Imaging in Preterm Neonates
Published on: December 31, 2015
Delayed cord clamping and blood flow in the superior vena cava in preterm infants: an observational study
Michael P Meyer1, Lindsay Mildenhall
1Kidz First, Middlemore Hospital, Auckland, New Zealand. mmeyer@middlemore.co.nz
Objective:
To determine if timing of cord clamping affects blood flow in the upper body, as measured by flow in the superior vena cava (SVC).
Design:
Observational study.
Setting:
Neonatal Unit, Middlemore Hospital, Auckland, New Zealand.
Patients:
30 preterm infants <30 weeks' gestational age.
Intervention:
Cord clamping was immediate in 17 infants and delayed by 30-45 s in 13.
Results:
Infants in the two groups did not differ significantly in terms of gestational age, gender or use of antenatal steroids. Median flow in the SVC in the first 24 h was significantly higher in the group with delayed clamping (median 91 ml/kg/min; IQR 81-101) compared with 52 ml/kg/min (IQR 42-100) in the immediate clamping group (p=0.028). Fewer infants in the delayed group had low flow (1 compared with 9; p=0.017). All three infants with intraventricular haemorrhage (IVH) (of any grade) had low flow.
Conclusions:
Blood flow in the SVC was higher in infants where delayed cord clamping was performed. The relationship of IVH, low flow and timing of cord clamping requires further study.
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