Ultrasound of the Week #004

This case again demonstrates great abdominal ultrasound views and the utility of abdominal ultrasound scanning.  Thanks again to Dr Salman Naeem (Ultrasound Fellow) for this case and images.

Case:

A 35 year old female presents with diarrhoea, vomiting, abdominal pain and PV bleeding for 12 days.

A quick look at the abdomen shows the following views:

There is a large amount of free fluid visible in the RUQ and LUQ views. The longitudinal suprapubic view shows a uterus with no convincing intrauterine pregnancy*. It does not show an obviously filled bladder (this should be anterior to the uterus) so she has likely passed urine (or more worryingly, may not be producing much urine due to shock).

Diagnosis: Ruptured ectopic pregnancy

This demonstrates nicely the classic distributions of free fluid in RUQ and LUQ.  These are the most common areas to find free fluid (but cases do not always follow this pattern!)

• In the RUQ, free fluid will most often collect in the Right Superior Paracolic Gutter (adjacent to the inferior edge of the liver – top right of our view).  This is usually the most sensitive area for free fluid collection in the supine patient as it is the most dependent area in the abdomen
• In the LUQ, free fluid will most often collect between the spleen and diaphragm, rather than the splenorenal recess. 

See last week’s case for an overview of FAST and the standard windows.  Remember, ‘FAST’ refers to abdominal sonography in trauma, but the skills can be utilised in other situations such as in this case. 

*N.B. Most emergency physicians will not seek formal accreditation in ultrasound in pregnancy, and so always advise your patient of the focus and limitations of your scan.  We are seeking to answer a focused question – ‘Is there free fluid in the abdomen?’, rather than detailed questions about the pregnancy/foetus