Dr Masri says staff at the hospital were stunned at the scale of the catastrophe, with "waves" of patients arriving all at once."I never imagined that an earthquake could create this much damage, could lead to this number of patients."Sadly, he is used to dealing with major incidents.In 2013, he was working in a field hospital when rockets containing the nerve agent sarin were fired at several opposition-held suburbs of the capital, Damascus. Hundreds of people were killed and thousands of others were injured.