Textbooks or "point of care" summaries are good sources for background information.
Search for scholarly articles in the following databases:
PubMed is provided by the National Library of Medicine covering the fields of Nursing, Anesthesia, Medicine and Health Professions. Click on the "Get it @ Bryan" button for access to full text (if available) or the article request form.
Practice guidelines and clinical guidelines are available from a wide variety of professional organizations.
Searching for additional organizations? An extensive list is available from MedlinePlus: https://medlineplus.gov/organizations/orgbytopic_a.html