By Rabbi Dovid Ostroff
Should one call a Jewish ambulance service or a regular one? It would depend on the nature of the call. If it is a dire emergency such as chest pains, profuse bleeding, unconsciousness, emergency childbirth or any other case where a life is endangered, one should call a Jewish ambulance service because of the reasons mentioned in the last shiur.If however the patient must be transferred to hospital but not in an emergency situation, such as a normal childbirth, a cut that requires stitching,  most fractures,  then it is sufficient to summon a regular ambulance service as there is ample time to reach the hospital and even if the service will dally in coming no adverse harm would be caused by the slight delay. Obviously, if there is reason to believe that by summoning the regular ambulance service the patient’s life would be endangered the Jewish ambulance service must be summoned.
What if one violated the Shabbos for pikuach nefesh and the patient did not require it, does one need to do teshuva?
The following can and does happen: If one witnesses a car accident, during the week, the first instinct is to call the ambulance service, but on Shabbos one might dally and say that others witnessed the accident as well and calling the service will be an unnecessary chilul Shabbos. This is a very incorrect attitude and a dangerous one, because everyone else could be thinking the same and thus the patient goes uncared for.
The correct attitude to have is as follows: The Shulchan Aruch says  “the doctors assessed that a patient (pikuach nefesh) requires a fresh fig and 10 people ran to pick the fig from a tree. They all picked a fig and ran back with their figs and gave them to the patient. Even if the patient ate the fig first brought to him and thus all the other figs were not needed, not only are they exempt from chilul Shabbos, they will all receive a just reward from Hashem for their virtuous intention. 
We see from this that one must not think twice when someone’s life is in danger and one must do all in one’s power to help in a pikuach nefesh situation. Even if retroactively one’s “chilul Shabbos” is unnecessary, it is not called chilul Shabbos and one receives a reward for attempting to save a Jewish life.
What if we are not sure whether it is pikuach nefesh? Is it permitted to violate the Shabbos?
The Shulchan Aruch  mentions a case where a roof caves into a room where people stood not long before. The following doubts are present: was somebody buried alive? If yes, is he still alive or dead?
It is understood that removing the building materials involves an issur d’oraisso – a biblical prohibition,  and nevertheless the halacha is that despite the doubts involved in this case one is commanded to violate the Shabbos and attempt to rescue people buried beneath the roof. It is possible that nobody is there and it is possible that it is too late and nothing can be done, which retroactively means that one violated the Shabbos for nothing.
This is irrelevant. One is commanded to violate the Shabbos even for a safek pikuach nefesh, as we learned that the keeping of Shabbos is not to pose an obstacle from saving one’s life.
How far does this go? What is considered a safek?
Here lies the difficult question, because on the one hand we do not want to take pikuach nefesh lightly and yet on the other hand we do not want to take Shabbos lightly either.
One must therefore be convinced that there is at least a certain measure of doubt that the case involves pikuach nefesh and when that is established, one should violate the Shabbos for that pikuach nefesh.
 There might be cases where it is an emergency but in most cases there is ample time to stitch.
 Obviously this is not intended to be a medical guideline and one must refer to a doctor or rav for a proper evaluation and halachik ruling, this is intended merely to give an idea of medical problems and how they are to be dealt with on Shabbos.
 Simon 328:15.
 The M”B 328:40 explains that each person though that he could bring the fig quicker than the other person and the patient required it as soon as possible. If the patient was not in immediate danger they would not have all been permitted to pick a fig.
 Simon 329:3.
 Which in itself requires an explanation, but it is irrelevant to the facts.