PDF graph to text for research study: Assistance / Advice please

Hello!
We have to write up a study on approx 5000 patients that we sedated. The sedation records are in PDF format, and includes the attached graph, which recorded the drugs used, the dosage and intervals of administration and the patient’s parameters measured at intervals (different coloured lines on the graph).
Is there a way that this information can be extracted and reproduced in a format that can assist us with the academic case series that we wish to publish?
The rest of the sedation record has the usual text entries (medical history etc), which I assume will be easier to extract.
I apologise in advance … I realise that this site/forum is for advanced users but I am unfamiliar with the more technical terms or specifics.
If this forum is the wrong place, I’ll appreciate if I can be pointed somewhere else.
Many thanks,
Andre