What was the method of approach?
Hemoperitonium can be evaluated by multiple view techniques by U.S, by exploratory laparotomy, CT, or diagnostic peritoneal lavage (DPL) as the criterion standard. Or by laparoscopy
WAS it just evaluation only.
What was the underlying cause for hemoperitonium to place the diagnosis code?
As per the info you provided, and since you seek the 49xxxx code, it seems it was a Laparotomy procedure. Was it so?
So, if evaluation alone by open approach, then I would like to use 49000,instead of 49020. 'Evaluation' laparotomy in your case, is mounting to 'exploration' laparotomy only. 'Exploratory laparotomy' will take care of removal of the bood clots and clearing of the hemoperitonium as its component.
But there should be definitely an underlying pathology which caused the hemoperitonium (Blood in the peritoneal cavity); hemoperitonium is not an entity of its own, but, a sequlae of say, trauma, perforation, rupture of visceral organs of ectopic rupture and so on.
49020 -49062 go for peritonitis, abscesses and lymphocele not for hemoperitonium.
I hope this could help you