Splitting Sentences Based on Changes in Sentiment Tone in Clinical Reports

I am working on clinical reports and facing a unique challenge. Often, a single sentence contains multiple shifts in sentiment tone. For example, a sentence might read: “The patient has fever and chills but denied any nausea or vomiting.” Here, the sentiment shifts within the same sentence. I am looking for methods or techniques to split such sentences based on these changes in sentiment, rather than classifying the sentiment of the entire sentence as a whole. Any insights or suggestions on how to approach this problem would be greatly appreciated.