Anecdotal observations about prehospital emergency medical care in major natural and human-made disasters, such as earthquakes, have suggested that some injured victims survive the initial impact, but eventually die because of a delay in the application of life-saving medical therapy.

A multidisciplinary, retrospective structured interview methodology to investigate injury risk factors, and causes and circumstances of prehospital death after major disasters was developed. In this study, a team of United States researchers and Costa Rican health officials conducted a survey of lay survivors and health care professionals who participated in the emergency medical response to the earthquake in Costa Rica on 22 April 1991.

Fifty-four deaths occurred prior to hospitatization (crude death rate = 0.4/1,000 population). Seventeen percent of these deaths (9/54) were of casualties who survived the initial impact but died at the scene or during transport. Twenty-two percent (2/9) were judged preventable if earlier emergency medical care had been available. Most injuries and deaths occurred in victims who were inside wooden buildings (p <.O1) as opposed to other building types or were pinned by rubble from building collapse. Autopsies performed on a sample of victims showed crush injury to be the predominant cause of death.

A substantial proportion of earthquake mortality in Costa Rica was protracted. Crush injury was the principal mechanism of injury and cause of death. The rapid institution of enhanced prehospital emergency medical services may be associated with a significant life- saving potential in these events.