UMEM Educational Pearls

Category: Vascular

Title: Hemorrhage Volume on Head CT-How Big is the Bleed?

Keywords: hemorrhage (PubMed Search)

Posted: 4/21/2008 by Rob Rogers, MD (Updated: 12/14/2019)
Click here to contact Rob Rogers, MD

Hemorrhage Volume on Head CT 

Ever wanted to speak the same language as our neurosurgical colleagues? Ever wonder what they are doing, calculating, or thinking about as they look at the head CT of the large intracranial hemorrhage? 

Most of the neurosurgeons want to know basic information about patients with head bleeds. One thing they always calculate is the hemorrhage volume...i.e. how many mLs of blood are in the bleed? This can be easily done in the ED by using the following formula: called the ABC formula

A X B X C/2 X 0.6= mL of blood

A= largest width of the bleed (in cm)

B=largest width perpindicular to A

C=number of cuts you see blood on

So, if A=2cm, B=2cm and the bleed is seen on 3 cuts.....

2 X 2 X 3/2 X 0.6=3.6 mL of blood (not very much in the opinion of a neurosurgeon)

Most of the big bleeds that neurosurgeons drain or take to the OR are 50 cc or so. So, when you call a neurosurgeon and tell them that the patient has 60 mLs of blood, you will definitely get their attention.