I’m currently on a month of Ortho nights and was asked by the Attending to look up an article about the median lethal dose (LD50) for falls, meaning, at what height when people fall, do 50% of them die. Although 10 years old, the article is pretty interesting and got me thinking about some fall patients I’ve taken care of in the past. I once had a patient who accidently fell 11 stories from a hotel and lived. But we’ll get back to that story in a bit.
A fun fact before we dive in:
The record for a fall from the greatest height where the person survived is held by Alan Magee, a WWII USAF pilot who jumped out of his plane at a startling 24,000 feet and landed in a pine forest (some sources say a glass roof). Fortunately for him, the forest (or the roof) was covered in snow which is believed to have decreased the energy of the impact due to its deformability. If you are looking for a great book about a fall survivor, check out When I Fell From the Sky, by Juliane Koepche, a 17 year old girl who fell 10,000 feet from her family’s airplane which ultimately crashed in the Amazon jungle in 1971.
The evidence on falls
The article, Prognostic factors in victims of falls from height, by Lapostolle et al, was published in Critical Care Medicine in 2005. The study took place in France, in a city near Paris with a population of 1.3 million people. The researchers worked with the local EMS agency, Service d’Aide Médicale Urgente (SAMU), to examine both pre-hospital and in-hospital mortality (death) from falls, with the goal of determining what characteristics of a fall, if any, factor into prognosis. There were 287 patients in the study, 97 (34%) of which ultimately died. In short, they determined that patient age, height of fall (e.g. 1 story vs 8), impact surface type (e.g. concrete vs snow) and body part that first touches the ground (e.g. head vs legs) all help predict how a patient will do.
Interestingly enough, they even looked at the circumstances leading to the fall (i.e. accident, suicide, escaping a burning building), and cause did not factor in to prognosis. When you stop and think about it for a second, it seems semi-reasonable that someone determined to commit suicide might be able to jump in such a way to be more successful in his mission. Yet, of the 123 patients who attempted suicide, only 45.5% were successful. So suicide was not more deadly of a fall.
Also of interest, landing feet first was much less deadly than landing on your stomach, with death rates of 5.6% and 57.1% respectively. Getting back to my patient who fell 11 stories and lived, he fell feet first. I believe he survived because his legs acted as a sort of crumple zone, absorbing some of the energy of the impact.
Figure 1 above is from the article, and shows what’s known as the median lethal dose (LD50) for falls, meaning, at what height of a fall will 50% of people die. In this study, it was determined to be just over 4 stories. You can see that in this study, with the exception of one person who fell 17 stories, 100% of the patients who fell from 8 stories or more died. Clearly there are exceptions to this in real life – the 17 story patient, my patient, Mr. Magee, Ms. Keopche – but statistically speaking, it’s extremely rare. So, next time you respond to a call or see a patient in the ED who fell 4 or more stories, know that they have a 50/50 chance of survival.
Sorry for the morbid topic, but that’s part of being on night shift I suppose.