Shaking-impact syndrome and lucidity

Abstract

There has been much debate on the differential contribution of impact and shaking to the intracranial pathology of shaking-impact syndrome.1Di Maio VJM The “shaken-baby syndrome”.N Engl J Med. 1998; 338: 1329Google Scholar, 2Wecht CH Shaken-baby syndrome.Am J Forensic Med Pathol. 1999; 20: 301-302Crossref PubMed Scopus (6) Google Scholar The clinical presentation of this syndrome has also been closely examined, with great attention being given to the presence or absence of the lucid interval between the traumatic event and the onset of symptoms. Definitive statements on conscious state are usually precluded by the lack, in most cases, of a reliable assessment of an infant immediately after injury. However, Duhaime and colleagues3Duhaime A-C Christian CW Rorke LB Zimmerman RA Nonaccidental head injury in infants—the “shaken-baby syndrome”.N Engl J Med. 1998; 338: 1822-1829Crossref PubMed Scopus (521) Google Scholar deduced that a lucid interval does not follow serious head injury in children who subsequently die with subdural haematomas and cerebral swelling. Similar conclusions were reached by Willman and colleagues,4Willman KY Bank DE Senac M Chadwick DL Restricting the time of injury in fatal inflicted head injuries.Child Abuse Neglect. 1997; 21: 929-940Crossref PubMed Scopus (71) Google Scholar who studied accidental head trauma in children who did not have extradural haematomas. Reliable witnesses of significant infant shakings have also noted an immediate change in conscious state.5Krous HF Byard RW Shaken infant syndrome: selected controversies.Pediatr Develop Pathol. 1999; 2: 497-498Crossref PubMed Scopus (25) Google Scholar Although these studies seem to have clarified matters, and while our own observations are that severe head trauma in infants is invariably associated with an immediate alteration in conscious state, there are still unanswered questions. Specifically, it is not clear what is meant by a lucid state in an infant, and who should verify whether this is present or not. Fluctuation of consciousness and altered mental state may be extremely difficult to identify in infancy. While a gold standard for the absence of lucidity in an infant would be an assessment by an experienced paediatrician immediately after trauma, this rarely occurs. Given that minor irritability and somnolence are common in uninjured infants, and that expert assessment of conscious state in the domestic setting is infrequent, comments on the presence or absence of lucidity by non-professionals on the basis of casual observation, often under suboptimal conditions, should not automatically be accepted as accurate. Indeed, even determination by professionals of what constitutes lucidity may be unreliable if there has not been specific training in paediatric evaluation. Ascertainment of when an infant with a severe inflicted head injury was last neurologically normal may also not be possible when the history relies heavily on the veracity of a person who may be, or may be associated with, the perpetrator. It is important then, that reports of the presence or absence of lucid interval made by a nonindependent witness of the events surrounding the episode of injury do not negate opinions based on clinical experience. Unfortunately, the uncertainties that persist surrounding the issue of lucidity in infants with inflicted injury mean that we are still left with considerable difficulties when we attempt to plot a time course for events in these serious, complex, and highly emotive cases.