How can I get out of a subpoena to witness?

I really have no information to offer on the case - I'm an ER nurse. I must have said something casually to an officer that got me into this mess. The trial date is the same day that my six month old son goes in for surgery on a tumor. Will the police come and arrest me at his hospital bed?
I have already called the crown repeatedly, getting no where. I have had my son's doctor contact them both by phone and in writing. Obviously I'm not leaving my son. What will happen to me? Will these people ever see reason and have some common sense?

You must act and you must act in time. Unless there is an agreement between the prosecutor's and the defence attorney's office that you won't have to show up on that particular day, the police will take you, doesn't matter what. Now, you are an E.R. nurse. Your institution must have a lawyer. You are part of the team. His job is to be there for you. Do not hesitate to contact him. Don't feel intimidated. He cannot charge you any fee. Remember? Your part of the team. And you asking him to speak up for you to post-pone your court appearence for humanitarian reasons.It is in the Criminal Code. Your fighting for your child. Be brave. My very best wishes for your child's speedy recovery and that you can put all the problems behind you.

You need to contact both prosecution & defence and ask them to change the date of your testimony.

You can't avoid going to court but they should be able to change it to a different day.

See if the solicitor will allow you to file your testimony either in writing or by recording (video or audio). As long as the magistrate or judge knows you are in the middle of a family crisis in the hospital, he "should" allow you some flexibility. If that is not an option, see if you can make arrangements to attend the hearing immediately prior to or after the surgical procedure. I know that is unappealing as a parent, but subpoena is the same as a warrant. It is not an option as to IF but WHEN. The when is what you should examine.

Really nothing you can do. They will issue a warrant for your arrest if you dont show up. Have you tried calling the D.A.?
Better yet, show up at the D.A.`s office with all your documents from the doctor.
Good luck

Go in person with documentation from the doctor to the county attorney's office and talk to them. They may decide you're not necessary as a witness. Right now, they don't know what you know and that's why they want you to testify to what you know.