This dissertation, composed of three manuscripts, provides a foundation for the evaluation of advancing sedation and excessive respiratory depression in terms of managing post-operative patient's pain with opioids. The first manuscript provides a framework for the concept of sedation in terms of how it is assessed and applied to post-operative pain management. The second manuscript is a qualitative review of the literature regarding the assessment of opioid induced sedation and advancing respiratory depression in regards to managing patient's pain. The third manuscript provides the dissertation study examining expert nurses' common meanings and shared practices with sedation in the context of postoperative pain management with opioids. Using Heidegger's interpretive phenomenological methods, interviews with expert post-anesthetic care unit nurses were conducted to capture the missing practical knowledge behind the nursing gestalt approach to managing patient's pain. The third manuscript is currently being prepared for submission to a journal focusing on pain management nursing. Further research studies are warranted.