What is Chandrashtama?
Chandrastam days are said to afflict a certain rasi when Chandra transits in the 8th rasi from that rasi [birth rasi]. Chandrashtama days are considered unsuitable for any good activity for that rasi during the 2 and half days, till the time Chandra stays in that rasi; this period is sometimes extended before and after for some.
When you are aware of your Chandrashtama days, you can be careful in your activities and avoid any major decisions during that time. Do your regular work only and contemplate within, always have a prayer on your lips.
It is a period of contemplation and a chance to identify faults within and aspire to rectify them.
Surgery is not advised during Chandrashtama at all.