A subjective analysis of participants’ views in a study of experimental modelling of imposed airway obstruction in infants and children

Deliberate airway obstruction is a well-recognised form of child abuse and one of the most common causes of death in cases of child homicide. Although classical signs such as petechial haemorrhages can be helpful in raising the suspicion of mechanical asphyxia, they are not always present. Therefore, distinguishing between bruising caused by accidents, medical conditions or non-accidental injury remains challenging. We aimed to characterise bruising patterns which are potentially more consistent with deliberate airway obstruction by means of an experimental modelling study. The first results of our project were previously published and demonstrated that bruising anywhere on the head may be consistent with deliberate upper airway obstruction. In this paper, we present the findings of a questionnaire carried out during the modelling to assess participants’ perception of force and consider how variables such as age, use of adjuncts and force distribution may affect bruising patterns in deliberate airway obstruction. Statistical analysis of our results showed that participants felt they were using less force in scenarios involving the infant rather than the child resuscitation dummy as well as when using adjuncts, meaning marks are likely to be more subtle. Therefore, in such cases it is important to examine for other signs of asphyxiation (such as petechiae) and consider the possibility that adjuncts might have been used which could make picking up localised injuries more difficult. Our results also showed that participants often felt force was not distributed evenly across the digits, reporting the greatest force through either the thumb in isolation or the thumb plus another digit in up to nearly 50% of cases. This suggests that just one or two bruises may be consistent with deliberate airway obstruction. •Airway obstruction is a form of physical child abuse which may result in bruising.•Theoretical fingertip bruising can be identified using experimental modelling.•Less subjective force was used in cases involving infants and the use of adjuncts.•Fingertip bruising may be subtler in such cases and should prompt further examination.•A single bruise may be consistent with intentional airway obstruction.