Ash Shaykh Muhammad Ibn Hizaam was asked:
A doctor was treating a man with a heart sickness, and the time for the obligatory prayer came in. If he stops treating the man he will die, but if he continues he will miss the prayer. What does he do in this situation?
He combines the prayer with the one before it, before he starts the surgery. If it is at the time of Thuhr and Asr he combines between them.
If it is in the night time, he combines between maghrib and Ishaa. The doctor knows the surgery will take time. Thus, he has an excuse to combine in this situation and act with the narration of Ibn Abbas that the prophet sallallahu alaihi wa Salam combined between Thuhr and Asr, and Maghrib and Ishaa without any fear or rain.
It was said: “what did the prophet sallallahu alaihi wa Salam intend by that?” He said he intended that there be no hardship upon his nation. This [surgery] is saving a life and it is an important matter. Thus there is no problem with combining between two prayers and completing his job.
He should seek the reward. It is incumbent upon the doctors who do this job that they seek the reward from Allah and their concern shouldn’t be wealth.
Majid Jawed Al-Afghanee