WHEN PARENTS LOSE THEIR COOL: THE SHAKEN BABY SYNDROME

Physical abuse is the leading cause of serious head injury in infants. When a child younger than one year of age has an intra-cranial injury, it should be presumed to have been due to child abuse. It has been estimated that when uncomplicated skull fractures are excluded, 95% of serious intracranial injuries and 64% of all head injuries in infants under 1 year of age are due to child abuse. The Shaken Baby Syndrome was first described in 1972 by a radiologist John Cassey. It occurs most often in infants younger than 6 months of age and is frequently overlooked in its most subtle form since there is often an absence of external visible injuries.

What are the clinical features of the Shaken Baby Syndrome?

The classic clinical findings include a constellation of retinal hemorrhages, subdural and surarachnoid hemorrhages with little or no evidence of external cranial trauma. Retinal hemorrhages are thought to occur in 75 to 90% of cases and may be unilateral or bilateral but may be missed unless the child is examined by a pediatric ophthalmologist. The symptoms and signs of the Shaken Baby Syndrome may be very subtle if only mild ocular or cerebral trauma has occurred. Infants may have a history of poor feeding, vomiting, lethargy and/or irritability occurring intermittently for days or weeks prior to the time of the initial health care examination. The subtle symptoms are often minimized by physicians or attributed to mild viral illnesses, feeding dysfunction or infant colic. Most often one caretaker is aware of the true etiology of injuries, the others are not. The caretaker who violently shakes the young infant causing unconsciousness may put the infant to bed hoping that the baby will later recover. In the extreme form of the Shaken Baby Syndrome the infant typically will present with seizures, in a coma, not sucking or swallowing, unable to follow movements and not vocalizing. Some infants will have respiratory difficulty with apnea or complete respiratory arrest. In the severe form of Shaken Baby Syndrome the diagnosis may be confused with meningitis, sepsis, or late hemorrhagic disease of the newborn due to vitamin K deficiency.

What investigations should be done?

Computed tomography (CT) is generally the method of choice for demonstrating subarachnoid hemorrhage. Magnetic resonance imaging is considered complementary to CT. Skull fractures that are multiple, bilateral, or cross suture lines are more likely to be nonaccidental in origin than simple linear fractures. A skeletal survey including the long bones, skull, spine and ribs should be obtained as soon as the infant's medical condition permits, in order to exclude multiple injuries. Single or multiple fractures of the midshaft or metaphysis of the long bones or rib fractures would confirm the suspicion of non-accidental injury in the young infant under 6 months of age. What steps should be taken by physicians who suspect or diagnose nonaccidental head injuries? Suspicion of nonaccidental head injury must be reported immediately to the appropriate authorities in order for them to institute a thorough investigation before the issues become muddied by time and the comparison of explanations by the infants' responsible caretakers. A team approach is the only reasonable way in which the management of child abuse can be successfully accomplished. Why do some parents shake their babies? What are the risk factors for inflicting cerebral trauma? Violent shaking of an infant is the caretaker's response to the tension and frustration frequently generated by a baby's incessant crying or irritability. Caretakers who are at risk for such abusive behavior generally have unrealistic expectations of their children and may exhibit a role reversal, whereby the parents expect their needs to be met by the child. Parents with psychiatric difficulties or those experiencing stress as a result of environmental, social, biologic or financial situations may also be more prone to impulsive and aggressive behavior. In some cases there is careless disregard for the child's safety and in other cases it is less clear whether there was an intent to inflict serious harm on the infant. What can be expected following the diagnosis of the Shaken Baby Syndrome? There is a high incidence of morbidity and mortality. If the infant presents in a coma, up to 60% may die, have profound mental retardation, spastic quadriplegia or severe motor dysfunction. Those infants who present with seizures, irritability, or lethargy with no lacerations or infarctions of brain tissue may have subtle neurologic sequelae or persistent seizures. The consequences of shaking infants who do not come to medical attention is unknown.

What can physicians do to prevent the occurrence of the Shaken Baby Syndrome?

As part of an anticipatory guidance, physicians should ask about parental stresses and their responses to the crying infant. Parents should be advised regarding the risks of shaking babies. Reading material on Shaken Baby Syndrome should be provided to all parents. An open channel of communication for stressed out parents should be made available. If baby-sitters are used, careful checking of references and employment history is mandatory since many of these caretakers have no experience and may simply be unemployed individuals looking for temporary work until a job situation presents itself.

 

Reference

Pediatrics 92: 872-75, 193.

 

 

---

Click to return to home page