Shaken Baby Syndrome

SBS was first noted by Caffey (1974) and called Whiplash Shaken Infant Syndrome. It is marked by

  • bilateral subdural/subarachnoid hematomas
  • cerebral contusion
  • bilateral retinal hemorrhages
  • all in the absence of any external signs of trauma to the head and neck

Additionally,

  • the infant's head circumference is often greater than 90th percentile (Ludwig & Warman, 1984)
  • the infant may have bloody cerebral-spinal fluid (Ludwig & Warman, 1984; Spear et. al., 1992).
  • the infant may also show fractures of the spine, cerebral palsies, trauma to the bones of the arms and legs, and retinal detachments may (Caffey, 1974).

It is sometimes undetected both because of the absence of obvious trauma and the parent-assailant's reluctance to admit the abuse. Shaking may be seen by some as simply inappropriate parenting behavior, and not as life-threatening abuse (Showers, 1992; Eagen et. al., 1985). SBS may be missed completely, or misdiagnosed as metabolic abnormalities, intoxication, or infection such as meningitis (Ludwig & Warman, 1984). Spear (et. al., 1992) noted that 1100 infants die of SBS each year.

According to Caffey, retinal hemorrhages occur in approximately 15% to 30% of infants (Sezen, 1970; Planten & Shaaf, 1971). They do not appear to result from traumatic birth, breech birth, or cesarean section, but rather from increases in intraocular venous pressure secondary to increases in central and/or intracranial venous pressure, or from rapid changes in intraocular venous pressure. They are also seen in cases of prematurity and blood disorders such as leukemia (Kaur & Taylor, 1992). They usually heal completely and rapidly after a few days. Retinal hemorrhages are seen in roughly 25% of abused children, in 50% - 100% of shaken babies, and in 89% of abused infants with head trauma. Retinal hemorrhages do not appear to follow accidental mild head injuries and only rarely follow severe head injuries (Buys et. al., 1992).

Infants are at a greater risk for damage secondary to shaking. The infant head is heavier and the neck muscles weaker. Rotational torque results in excessive tearing forces at the attachment of blood vessels to soft tissues. The greater amount of cerebral-spinal fluid can shift faster and farther, increasing the stretching of softer and less myelinated tissues (Caffey, 1974). Infants may also be at greater risk to be shaken, as they cry more often for no apparent reason and their care and supervision demand greater time and energy from parents/caretakers (Ludwig & Warman, 1984).

However, gentle rhythmic shaking, when the caregiver is not angry and is in control of his/her strength, can be helpful in stimulating the vestibular system to improve balance and the visual system to improve visual tracking of objects, as well as inducing sleep. The difference between good shaking and bad shaking is that good shaking allows for support of the head and neck.

Prognosis

The overall prognosis is poor:

  • common damage includes diffuse cerebral edema, enlargement of the ventricles, and gray and white matter atrophy (Frank et. al., 1985)
  • CNS problems, such as lethargy, irritability, and seizures (Ludwig & Warman, 1984) are common too
  • many unexplained cases of MR may stem from SBS (Caffey, 1974) as well as SIDS (Showers, 1992)

Using a small sample (n=20) drawn from the Child Protective Services Agency at the Children's Hospital of Philadelphia from 1977 to 1982, Ludwig and Warman (1984) found a high mortality rate (15%) and morbidity rate (50% -- blindness and visual impairment, motor impairment, seizures, and developmental delay). 35% of the shaken children they studied survived without apparent morbidity.

Showers (1992) notes that several studies undertaken between 1982 and 1990 indicated that 25 - 50% of adults and teens did not know that shaking a baby was dangerous. She began the "Don't shake the baby" project in Ohio and reports some success with the posters, videotape, and written materials in educating parents regarding the dangers of shaking.

Resources

  • Buys, Y. M., Levin, A. V., Enzenauer, R. W., Elder, J. E., Letourneau, M. A., Humphreys, R. P., Mian, M., & Morin, D., (1992). Retinal findings after head trauma in infants and young children. Opthalmology, 99(11), 1718-1723.
  • Caffey, J., (1974). The whiplash shaken infant syndrome: Manual shaking by the extremities with whiplash-induced intracranial and intraocular bleedings, linked with residual permanent brain damage and mental retardation. Pediatrics, 54(4) 396-403.
  • Eagan, B. A., Whelan-Williams, S., & Brooks, W. G., (1985). The abuse of infants by manual shaking: Medical, social, and legal issues. Journal of the Florida Medical Association, 72(7), 503-507.
  • Kaur, B., & Taylor, D., (1992). Fundus hemorrhages in infancy. Survey of opthalmology, 37(1), 1-17.
  • Frank, Y., Zimmerman, R., & Leeds, N. M., (1985). Neurological manifestations in abused children who have been shaken. Developmental Medicine & Child Neurology, 27, 312-316.
  • Ludwig, S. & Warman, M. (1984). Shaken baby syndrome: A review of 20 cases. Annals of Emergency Medicine, 13(2), 104-107.
  • Showers, J. (1992). Shaken baby syndrome: the problem and a model for prevention. Children Today, 21(2), 34-37.
  • Spear, R. M., Chadwick, D., & Peterson, B. M. (1992). Fatalities associated with misinterpretation of bloody cerebrospinal fluid in the "Shaken Baby Syndrome." The Pediatric Forum, 146(12), 1415-1417.