Objective: To determine the occurrence of weapon carriage by major tra
uma patients at a university/county hospital ED. Methods: Retrospectiv
e observational study of major trauma patients seen in the ED of a maj
or urban trauma center in Los Angeles from 1979 to 1993. All major tra
uma patients were searched routinely for weapons by the security polic
e. Cases of violence in the ED caused by these weapons were reviewed.
Results: Over the 14-year period, 26.7% of the victims of major trauma
presenting to ED were armed with lethal weapons. The occurrence of au
tomatic weapon seizure increased significantly from an annual rate of
only 0.2 in the first five years to an average of 17 over the last fiv
e years (p < 0.001). A total of 115 ''incidents'' of violence involvin
g weapons in the ED were recorded during this period; 1.7% of the weap
ons brought to the ED fed to violence and injury. There were four fata
lities of armed and dangerous patients, but only six minor injuries to
the staff. No other (unarmed) patient in the ED at the time of these
incidents was injured. Conclusions: ED major trauma patients at one ur
ban trauma center in Los Angeles frequently carry weapons, including a
utomatic military weapons. In addition to violence prevention measures
such as weapon confiscation, plans must be made and practiced for the
management of violence within the ''sacrosanct'' hospital doors to pr
otect both patients and ED personnel.