You can withdraw from your IRA as many times as you want. All that matters is the total amount that you withdraw during the year. It makes no difference whether you make one big withdrawal or a lot of small withdrawals.
In the IRS information that TomD8 referred you to, note that total and permanent disability is one of the exceptions to the 10% penalties. See IRS Publication 590-B for the details of what is considered disabled for IRA withdrawals.
