Hello and welcome to JustAnswer. Please note:This is general information and is not legal advice. No specific course of action is proposed herein, and no attorney-client relationship or privilege is formed by speaking to an expert on this site. By continuing, you confirm that you understand and agree to these terms.
I am very sorry to hear about your loss.
This falls under HIPAA laws - the Health Insurance Portability and Accountability Act of 1996 which creates privacy rights for patients even after their passing. These are medical records, so they fall under HIPAA.
Under HIPAA, a Personal Representative can request records. See HERE. For the deceased, it is the executor or administrator of the estate. I am afraid that there is a law for this, and it states that a registered executor or administrator of the estate can request the records. There is no automatic allowance for a surviving spouse.
Just because there is little/no money in the estate does not mean that no probate is necessary. Probate may be used for more than just to get access to accounts and transfer title - it may be used to act in the deceased's name, and this is exactly what this would be. So yes, probate is required. Once probate is filed, the Executor of the estate gets something called a Letter of Testament/Administration (hereinafter "Letter"). This Letter will allow the Executor (i.e. you) to get the records.
Actually, because her estate is small, one can file for small estate administration which is essentially probate by mail - making much quicker and easier to get those Letters and become the Executor (in HIPPA's eyes, Personal Representative). See HERE. Counsel is recommended but not mandatory.
Please note: If I tell you simply what you wish to hear, this would be unfair to you. I need to be honest with you and sometimes this means providing information that is not optimal. Negative ratings are reserved for experts who are rude or for erroneous information. Please rate me on the quality of my information; do not punish me for my honesty.
I hope this helps and clarifies. Please use the SEND or REPLY button to keep chatting, or please RATE when finished. You may always ask follow ups at no charge after rating. Kindly rate my answer as one of TOP THREE FACES/STARS and then SUBMIT, as this is how I get credit for my time with you. Rating my answer the bottom two faces/stars or failing to submit the rating does not give me credit and reflects poorly on me, even if my answer is correct. I work very hard to formulate an informative and honest answer for you; please reciprocate my good faith with a positive rating.