Help with work formula - medical application

[aliberty]

My wife is a nurse in an intensive care unit. Last year, she suffered a back injury, and has gradually returned to almost full duty. (She has lifting and carrying restrictions placed on her by her physician, limiting the amount of weight she can lift and carry.) A few days ago, she was trying to roll an unresponsive 280 pound patient onto his side. In doing so, she strained her back, and was in pain for a couple of days. Is there a simple formula for us non-physics literate folks that would allow her to determine how much weight she is "lifting" in such a circumstance (i.e., rolling a heavy patient) based on the weight of the patient? This way, she could monitor her actions, and decline to be assigned a patient whose weight would result in exceeding the lift/carry restrictions when she has to roll him or her. Thanks so much in advance for the help.

Art Liberty

 

[Gokul43201]

The data given is insufficient for such a calculation. A lot will depend on the body shape, stiffness of the mattress, rate of liflting the patient and things like, whether the patient's hand is in the way.

It is possible, however to make an rough estimate. Assuming the lifting is done slowly, the maximum force required would be about half the patient's weight or 140 lbs. If the patient looks more like a cylindrical log than a rectangular block, this number will be less.

An accurate calculation will most likely give a smaller number than 140 but that is a little hard to do with the available info. It might be easier to estimate this experimentally, using some force measuring device like a spring balance.

 

[aliberty]

Thanks. I understand this cannot be answered acurately with the limited data, but your rough estimate is helpful and should be sufficient to avoid furthyer injury.