Fatal road accidents in Birmingham: times to death and their causes.

Abstract The intervals between injury and death in the 254 fatalities after road traffic accidents in Birmingham during 1969 and 1970 were analysed and correlated with other data. Sixty-three per cent were pedestrians and 23 per cent were passengers and drivers of vehicles. In round figures, about a third of the series died within half an hour, a half by 2 hours, two-thirds by 24 hours, and three-quarters by 2–4 days. The patterns of survival-time could be divided into three phases. There was an early steep decline, with 36 per cent dying during the first half-hour and 44 per cent within 1 hour of the accidents. This was followed by a longer stage during which the rate of dying decreased progressively in logarithmic fashion. The cumulative tolls were 51 per cent by 2 hours, 58 per cent by 4 hours, 68 per cent by 24 hours, and 83 per cent by 7 days. The curve then flattened into a prolonged tail. Between 7 and 28 days another 10 per cent died, making 93 per cent by 28 days. The remaining 7 per cent succumbed during the subsequent weeks and months, 3 patients surviving longer than a year. Fifty-six per cent of vehicle occupants and 40 per cent of pedestrians died within an hour of injury, and the excess of rapid deaths among vehicle occupants was mainly due to a higher proportion of rupture of the aorta. All the ruptured aortae in vehicle occupants occurred after accidents at night or the early hours of the morning. Many of the affected drivers and passengers had consumed alcohol and their injuries were more rapidly lethal than after accidents at other times. Serious cerebral trauma dominated all groups of road users and multiple injuries were common. Included among the fatality tail was a group of subjects, mainly pedestrians, with relatively modest injuries who might have survived had they not developed pulmonary embolism, respiratory infection, or other complications.