DROWNING

Summary: Globally, drowning is the fourth commonest cause of death of school-age children. Many drowning victims are disabled, and Proximate Causes are age-specific. Outcome tends to be at one extreme or the other - death or severe brain-damage on the one hand, or survival relatively neurologically intact on the other. Some of the older clinical research literature uses confusing terminology.

Worldwide, drowning is the commonest cause of death for males age 5-14¹.

In the US, in the first two decades of life drowning accounts for 10% of deaths from accidental injury², 4000 deaths a year in all. Childhood and adolescent immersions result in about 8000 hospitalisations and 31,000 Emergency Department visits annually³. Of all US drowning deaths, 60% are children and teenagers.

ASSOCIATED CAUSES

Many drowning victims are disabled, and Proximate Causes are age-specific.

Nearly a third of children have pre-existing conditions⁴ - congenital heart disease, seizure disorder, cerebral palsy/mental retardation, and developmental delay.

Causal factors clearly associated with drowning are for toddlers inadequate supervision⁵, for young children inflicted immersion^5, ⁶ (particularly bath-tub⁷), and for adolescents and adults alcohol and drugs⁸.

Associated traumatic injuries are generally caused by diving, vehicle crashes, falls from a height, and boating accidents^9, ¹⁰.

Practice Point

Clinical research on the common patterns of injury can be valuable in litigating drowning

OUTCOME

Outcome tends to be at one extreme or the other - death or severe brain-damage on the one hand, or survival relatively neurologically intact on the other.

Of children who lose consciousness in the water, those who are in cardiac arrest on arrival at the Emergency Department will likely either die or prove to be severely brain-damaged¹¹. Of those not in cardiac arrest and responsive to stimulation, the vast majority will survive and generally be neurologically intact¹². Other indicators of good neurological prognosis are Glasgow Coma Score of more than 5 on arrival at the Emergency Department¹³, and spontaneous respiration immediately after Cardio-Pulmonary Resuscitation¹⁴.

Although hypothermic protection of the brain occasionally occurs in frigid conditions (fall through ice, for instance), hypothermia is generally an indicator of poor prognosis¹⁵.

Survivors of immersion may suffer pneumonia and, for up to 5 days post-submersion, the onset of Acute Respiratory Distress Syndrome (ARDS).

Practice Point

Outcome is largely predictable at the time of resuscitation, and deviations from expectation may indicate a novus actus interveniens

TERMINOLOGY

Some of the older clinical research literature uses confusing terminology.

The term secondary drowning for ARDS and other late complications may be found in the older clinical research literature, but has been abandoned. The term secondary drowning is currently used to indicate the medical equivalent of Thin Skull or Proximate Cause.

The term near-drowning is confusing and should probably also be abandoned³. "Drowning is defined as death resulting from suffocation within 24 hours of submersion in a liquid medium, and near-drowning, as survival of at least 24 hours after an episode of suffocation caused by submersion in a liquid medium." The author points out that "near" is used as a modifier in no other diagnosis and that 24 hours is arbitrary, having no patho-physiological rationale.

Practice Point

Litigators should understand the pathological implications of the terms secondary drowning and near-drowning

DIAGNOSIS

Personal Injury counsel should be aware that autopsy proof of drowning may be difficult¹⁶.