According to a 2007 Dutch study, there's a chance that a cell phone call in the wrong spot can cause ventilators, syringe pumps, or even pacemakers to pulse incorrectly. Therefore, cell phones should not be used in premises of hospitals.
Hoax or Fact:
Mixture of hoax and facts.
This message was widely spreading, that mobile phones should not be
used in hospitals, as they can interfere with the performance of medical machines. But the judgement is out, the findings of Mayo Clinic study explain that there are no "significant" instances of "clinically important" interference between cell phones and medical machines. Mobile Phones are safe to Use in hospitals, more so because that is an important means of communication. The Mayo researchers in fact advised the hospitals to revise or drop their cell phone bans in their premises.
However, it is important here to note that some of the sensitive medical equipment in hospitals can be effected with electrical interference of the cell phones. So, such sensitive equipment should be supervised by the hospital staff, making sure of avoiding cell phones where ever needed.