“Perioperative” is a term used to describe the time around surgery.
This article describes what happens in each of these three perioperative phases.
Prior to intake, that person will usually be the treating doctor and/or surgeon.

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Intraoperative Phase
The second phase, known as the intraoperative phase, involves the surgery itself.
(In smaller hospitals, the same person may be tasked with both responsibilities.)
Postoperative care is mainly focused on monitoring and managing the patients physiological health and aiding in postsurgical recovery.
Association of periOperative Registered Nurses.Colleges of nursing - faculty tool kit.
Celik F, Edipoglu IS.Evaluation of preoperative anxiety and fear of anesthesia using APAIS score.Eur J Med Res.
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