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Re: Monitoring of Newborn Weight, breast Feeding and Severe Neurological Sequelae secondary to dehydrati

Dear Editor,

With respect to van Dommelen et al’s(1) interesting paper we would like to make the following contribution.

Neonatal hypernatraemic dehydration screening is complicated by an unclear but possibly rising incidence(2) and the need to avoid undermining the ‘breast is best’ message whilst recognizing the severity of the condition. The notoriously variable clinical presentation adds to this difficulty.

In common with many centres we have seen a number of dehydrated babies following a period of sub-optimal feeding. A number of these babies have had severe neurological impairment following thrombotic events secondary to dehydration. We report four such cases, three breast feed and one mixed breast / formula fed, who presented to our paediatric unit in the last 5 years:

Case 1: A healthy second child, born at term by LSCS for failure to progress, discharged on day 4 having established breast feeding – 40 minutes every 3 -4 hours. Admitted at 11 days old with a four day history of being floppy, quiet and one day of recognised poor feeding. Weight not checked since discharge.

Found to have hypernatraemic dehydration (Na 190, birth wt 3.06kg admission wt 2.2kg, 28% drop from birth weight). Her dehydration resulted in acute renal failure requiring peritoneal dialysis and a cranial venous sinus thrombosis with haemorrhagic venous infarction. No inter-current infection, inborn error of metabolism, primary renal disorder or gastrointestinal cause of fluid loss was identified. She is now 5 years old and has asymmetric spastic quadriplegia and remote symptomatic epilepsy.

Case 2: First child, born at 42/40 by LSCS for cephalopelvic disproportion, birth weight 3.84 kg, apgars 91, 105. Breast feeding was difficult and she was admitted to NNU on day 4 clinically and biochemically dehydrated and polycythaemic (Hb 24). Seizures commenced on day 4 and CT suggested a haemorrhagic venous infarction secondary to sagittal sinus thrombosis. This has resulted in remote symptomatic epilepsy secondary to a small, deep, white matter lesion in the right frontal lobe. Her seizures have improved markedly since receiving epilepsy surgery.

Case 3: 38/40 girl, 2nd child, ventriculomegaly on antenatal U/S, born at home, birth wt 3.01 kg. Early twitching movements seen by midwife but felt to be normal. Poor mixed breast / bottle feeding with only ~4oz milk/24 hours taken in the few days prior to admission. Reviewed by a different midwife each day & once by GP, feeding and social concerns noted.

Admitted at 7 days old peripherally shut down, hypothermic, having apnoeic episodes, weight 2.50 kg (16.9% weight loss), polycythaemic (Hb 24), maximum Na 150. Microbiology demonstrated Group B streptococcal septicaemia and meningitis and her PICU stay was complicated by DIC, a sagittal sinus thrombosis and haemorrhagic venous infarct. At 4 years old she has mild cerebral palsy affecting her lower limbs more than upper, is visually impaired and has mild developmental delay.

Case 4: Breast fed, term baby girl, first child of a 40 year old mother. Discharged home one day after delivery. Seen at home by a community midwife and poor feeding noted. Readmitted at 9 days old moribund with severe hypernatraemic dehydration (Na 190, weight loss > 12%), capillary refill time of 6 seconds, absent femoral pulses and unrecordable blood pressure in the lower limbs. An echo excluded transposition but demonstrated an IVC thrombosis. A prolonged PICU stay was complicated by necrotic, perforated gut needing an iliostomy, seizures, acute tubular necrosis and a cardiac arrest. Long term renal problems are anticipated and survival is not assured.

We agree with Dr. Modi’s commentary(3) that sensitivity rather than specificity should be the focus of a screening regime given the severity of neurological problems that may follow severe dehydration. Any screening guideline needs to have an evidence base whilst remaining pragmatic and working within the resources available. The weighing policy advocated by McKie et al(4) seems to meet these targets and in addition has been shown not to discourage breast feeding. The intervention points for formula fed infants are supported by data reported by MacDonald et al(5).

There is more to assessing and supporting breast feeding than merely weighing babies. In an era of six hour discharges from maternity units and fragmented, geographically distant families support can be compromised. Community midwifery services are often stretched and there seems to be value in a ‘red flag’ marker, in terms of weight loss, to identify those mother-baby dyads that need additional support beyond that routinely delivered.

For babies highlighted in this way it would be important to distinguish, preferably in the community, between the hungry but healthy baby and the quiet, unwell baby. Management could then proceed as ‘breast is best’ for the well baby, for the dehydrated – rehydration. Telling the two apart is the trick.

References

1. Van Dommelen P, van Wouwe JP, Breuning-Boers JM, van Buuren S, Verkerk PH. Reference chart for relative weight change to detect hypernatraemic dehydration. Arch Dis Child 2007; 92: 490-494.

2. Harding D, Cairns P, Gupta S et al. Why bother weighing breast fed babies? Arch Dis Child Fetal Neonatal Ed 2001; 85: F145.

3. Modi N. Avoiding hypernatraemic dehydration in healthy term infants. Arch Dis Child 2007;92: 474.

4. McKie A, Young D, MacDonald PD, Does monitoring newborn weight discourage breast feeding? Arch Dis Child 2006; 91: 44-46.

5. MacDonald PD, Ross SR, Grant L, Young D. Neonatal weight loss in breast and formula fed infants. Arch Dis Child Fetal Neonatal 2003; 88: F472

Dr. Joe Fawke MBChB MRCPH Clinical Research Fellow & Neonatal SpR, School of Human Development, University of Nottingham

Dr WP Whitehouse, BSc, FRCP, FRCPCH, Clinical Senior Lecturer in Paediatric Neurology, School of Human Development, University of Nottingham, E Floor, East Block, Queen’s Medical Centre, Nottingham NG7 2UH, UK

Conflict of Interest: none