Dear Sir Professor Weindling questions why therapeutic hypothermia, an intervention that may be incompletely proven, has been widely adopted into clinical practice whereas other interventions such as delayed cord clamping (DCC) have not.[1] DCC has been subjected to RCTs and meta-analyses all of which demonstrate benefits for both term and premature infants with no evidence of any harmful effects.[2] We consider that DCC should not be viewed as an intervention but rather as the allowance of a physiologically normal transition from intra to extra uterine life. On the other hand immediate or early cord clamping is clearly a medical intervention and one for which there is no evidence of benefit to either the mother or the newborn infant.

Early cord clamping deprives the newborn of the 20ml/kg of blood which would have passed from the placenta to the newborn in the first few minutes of life. Trials of only a 30 second delay in preterm infants have shown worthwhile benefits as Professor Weindling states in his article. Several bodies now recommend some delay in cord clamping where clinicians feel that this is possible. For example, the Newborn Life Support Course teaches that the umbilical cord "can usually be clamped at a minute after delivery" and also that "very early clamping...can cause hypovolaemia".[3] The World Health Organisation,[4] the International Federation of Gynaecology and Obstetrics [5] and two Cochrane reviews [6,7] also support DCC. Despite these recommendations most infants born in the UK will be subjected to the intervention of immediate or early cord clamping.

Both our Units have a written policy of delayed cord clamping at birth. We find that there is considerable difficulty in maintaining the practice due to frequent changes of junior staff both in Obstetrics and Paediatrics. The majority of junior staff come from units in which early cord clamping is the norm. Staff are often concerned that DCC will cause significant jaundice and polycythaemia and also delay resuscitative efforts if these are required. Analysis of fifteen trials enrolling nearly 2,000 infants showed no excess problems with jaundice or respiratory distress. Polycythaemia was more frequent but not found to be in any way harmful.[2] Whilst the policy of DCC is relatively easy to institute in well term babies, staff find it more difficult to delay clamping even for 30 seconds in premature infants and term infants who appear in need of resuscitation. These infants, who are least likely to get delayed clamping, are probably the ones who are most likely to benefit from both the rapid transfusion of placental blood and also the continuation of gas exchange via the placental circulation whilst regular breathing becomes established.

The effectiveness of the placental circulation in the first few minutes after birth was highlighted recently at one of our hospitals by the case of a term infant born by elective caesarean section. The infant was delivered onto the mother's thighs and became centrally pink within the first minute of life. The infant's cord was clamped at two minutes and he rapidly became cyanosed. Echocardiography at thirty minutes of age demonstrated transposition of the great arteries with intact ventricular septum and patent ductus arteriosus. Good oxygenation during the first two minutes of life had been achieved because the placental circulation was intact. We hypothesise that babies who have become significantly hypoxic during the birth process may benefit from an intact umbilical cord during the first few minutes of postnatal life whilst the infant is being assessed and resuscitated. We believe that studies to evaluate how resuscitation with an intact placental circulation could be achieved and any benefits that may accrue are required.

Dr Andrew Gallagher Consultant Paediatrician, Worcestershire Royal Hospital, Worcester, WR5 1DD

Mr David Hutchon Consultant Obstetrician, Darlington Memorial Hospital, Darlington, DL3 6HX

References

1. Weindling AM. How has research in the last 5 years changed my clinical practice? Arch Dis Child Fetal Neonatal Ed 2010; 95:F64-68.

2. Hutton EK, Hassan ES. Late vs early clamping of the umbilical cord in full-term neonates. Systematic review and meta-analysis of controlled trials. JAMA 2007;297(11):1241-1252

3. Resuscitation Council (uk). Resuscitation at birth - Newborn life support provider course manual. 2001

4. World Health Organization (WHO). WHO recommendations for the prevention of postpartum haemorrhage. Geneva, Switzerland: World Health Organization (WHO); 2007.

5. International Confederation of Midwives and the International Federation of Gynecologists and Obstetricians. Management of the third stage of labour to prevent post-partum haemorrhage 2003. http://www.figo.org/projects/prevent (accessed Feb 2010)

6. Rabe H, Reynolds G, Diaz-Rossello J. Early vs delayed umbilical cord clamping in preterm infants. Cochrane Database Syst Rev 2004;(4):CD003248.

7. McDonald SJ, Middleton P. Effect of timing of umbilical cord clamping of term infants on maternal and neonatal outcomes. Cochrane Database Syst Rev 2008;(2): CD004074.

Conflict of Interest:

None declared