Friday, July 31, 2009

Head Trauma outcomes of verifiable falls in newborn babies

Authors:

Caroline Ruddick, Martin Ward Platt, Camille Lazaro

Affiliations:

Ms Caroline Ruddick, Midwifery Manager, Directorate of Women’s ServicesDr Martin Ward Platt, Consultant Paediatrician, Directorate of Women’s ServicesDr Camille Lazaro, Consultant Paediatrician, Department of Child Health

Corresponding author:

Dr Martin Ward PlattWard 35Royal Victoria Infirmary,Newcastle upon Tyne NE1 4LPTele: 0191 282 5197Fax: 0191 282 5038E mail: m.p.ward-platt@ncl.ac.ukJuly 7, 2009 as 10.1136/adc.2008.143131

Head trauma outcomes of verifiable falls in newborn babies

Abstract

Eleven newborn babies of normal weights sustained falls onto a hard surface in hospital. The one baby who fell from over a metre sustained clinical and radiological trauma and encephalopathy, with a skull fracture and cerebral contusion. No other baby demonstrated neurological signs despite the presence of parietal skull fractures in four of six who were X-rayed; only two babies had scalp swelling. The findings suggest that parietal fractures can result from very low level falls and scalp swelling is a poor marker for underlying fracture.

Introduction

The conditions under which very young infants can sustain skull fractures can be contentious, but are clearly important in determining whether an injury might be consistent with the history given.Studies of linear skull fractures and external evidence of skull injury have mostly focused on falls of 3 feet or more1 2, so there is little information on the outcomes of lower level falls. In the context of the accident and emergency department, the prevarication and false histories that are part of thepresentation of child abuse create difficulties for clinicians and researchers alike.

Therefore, we believed it would be useful to present our experience of injuries sustained from falls in newborn babies in the postnatal ward where the fall occurred under verifiable conditions, or was witnessed by someone other than the mother; there was information about the physical environment; immediate medical assessment was available; and many of the falls were from heights as low as 0.5m.

Method

We used our adverse event register, cross checked with the codings for all trauma in newborn babies from the Hospital Episode Statistics, to identify cases where babies fell accidentally to the floor in our maternity unit for the five years January 1999 to December 2003. The records for each child were examined; details of the height to impact, nature of the surface struck, clinical symptoms and the results of any imaging were identified for each child.

Results

The details of the babies are given in the table. 11 babies were identified, seven girls and four boys,all born at term. Birth weights ranged from 2.1 kg to 3.8 kg. Of the 11, seven were totally breast fed, three artificially fed and one mixed fed. Seven of the falls occurred at night, between the hours of 8 p.m. and 8 a.m. Four babies dropped to the floor when their mothers fell asleep following breast feeding.

The estimated distance to impact in most babies was one metre or less. One baby fell about 1.2m. The surface impacted upon in all falls consisted of vinyl tiles laid upon concrete with an intervening solid screed.No clinical findings were identified in eight of the eleven babies. Of the three with clinical findings,one had a bruise over the temporal area, one had a swelling over the parietal area and one had signs of traumatic encephalopathy.

All imaging was at the discretion of the attending physicians. Six of the eleven babies had skull Xrays, one had a CT scan (but no skull X-ray), and two an ultrasound scan. Of the six with X-rays, five had no scalp swelling, but three of these five had a solitary linear parietal skull fracture. Three of the eleven babies had localised scalp swelling, of which two were imaged and each of these had asingle linear parietal fracture. The baby who fell 1.2m had a fronto-parietal contusion beneath the fracture, and had a transiently decreased level of consciousness consistent with a mild traumatic encephalopathy; this baby was born by normal vaginal delivery.

Discussion

Our observations demonstrate that low height falls of under a metre can cause a linear skull fracture, and such skull fractures are not necessarily accompanied by a boggy swelling in the overlying scalp. However not all babies were radiographed so we cannot make any estimate of the rate of fracture among babies who fall.All the fractures, including that caused by the highest fall, were linear and confined to the parietes. Even the baby falling further, and sustaining brain contusion, had a linear fracture, not a more complex one. Although this finding supports the contention that complex, stellate or occipital fractures do not arise from simple domestic falls3 we cannot rule out the possibility that otherkinds of fracture could result from falls such as we have seen.In spite of the fact that hospital floors are particularly hard and unyielding, we found that symptoms suggestive of underlying brain injury (decreased consciousness, feeding problems, irritability,seizures or apnoea) were not found in 10 of 11 babies, even when fractures were found to have occurred. Existing biomechanical evidence suggests that that there is little difference in the effects of falls onto a hard floor or a carpeted domestic floor 4.

We conclude that even very low level falls may produce linear skull fractures, but that such fractures may occur without the scalp swelling traditionally considered suggestive of a fracture.

References

1. Greenes, D. S., Schutzman, S A. Infants with isolated skull fracture: what are their clinicalcharacteristics, and do they require hospitalization? Annals of Emergency Medicine. 1997;30:253-9.

2. Johnson, K., Fischer, T., Chapman, S., Wilson, B. Accidental head injuries in children under 5years of age. Clinical Radiology 2005;60:464-8.

3. Hobbs, C.J. Skull Fracture and the diagnosis of abuse. Archives of Disease in Childhood1984;59:246-52.

4. Coats, B., Margulies, S. S. Potential for head injuries in infants from low-height falls. Journalof Neurosurgery: Pediatrics 2008;2:321-30.

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