Figure. HR5th Bonus View of AFAST®. The target-organs, “HR” for “Hepato-Renal” are the right kidney and the adjacent right liver. The right kidney is more cranial than the left and thus the scanning plane must be directed far cranial towards the head of the patient. Moreover, the right kidney is cupped in the renal fossa of the liver and thus blends into the right liver sonographically. By performing this view in the standing position, air-filled loops of gastrointestinal tract fall away from the HR5th Bonus view target-organs.
When your patient is in RIGHT lateral recumbency or standing, AFAST® is performed by imaging in the same standardized order of the Diaphragmatico-Hepatic (DH) view, followed by the Spleno-Renal (SR) view (least gravity-depender), the Cysto-Colic (CC) view and then ending at the most gravity-dependent view, now renamed more accurately, the Spleno-Intestino Umbilical (SIU) view. The SIU view is performed at the level of the umbilicus and directing the scanning plane into the AFAST®’s most gravity-dependent pouch called the “Umbilical Pouch” followed by the Focused Spleen. These first 4 views, DH, SR, CC, and SIU, make up the AFAST® Abdominal Fluid Scoring System and the patient’s total Abdominal Fluid Score (AFS).
The HR5th Bonus view is not part of the AFAST® Abdominal Fluid Scoring System but is still scored and evaluated for any soft tissue abnormalities of its target organs of the right kidney and adjacent right liver. We traditionally have performed the HR5th Bonus view as the final 15th view of Global FAST® with the patient standing so that air-filled loops of gastrointestinal tract fall away from the right kidney and liver. However, more recently we have noticed during training sessions that while beginning the right Vet BLUE® and locating the “curtain sign”at the first Vet BLUE® Caudodorsal view, that the right kidney is generally at the same upper level along the body wall. Thus, by sliding more caudally from the “curtain sign” along that same upper level, the HR5th Bonus view is imaged more quickly. So the RIGHT Global FAST® Blend order is now becoming HR5th Bonus view, then right Vet BLUE®, followed and ending on the short- and long-axis fundamental TFAST® views of the heart.
Figure. HR5th Bonus View. From 2nd Edition of our textbook, Point of Care Ultrasound Techniques for the Small Animal Practitioner, Wiley ©2021.
Some Final Comments. So what about looking at the RIGHT kidney? In small dogs and most cats if you have enough depth, often you can view the both the RIGHT and LEFT kidney from the SR view with patients placed in RIGHT lateral recumbency. However, the HR5th Bonus view is most often performed by the author by having the patient stand and making this view the final 15th view of Global FAST® or more recently performed before right Vet BLUE® sliding caudal to the “curtain sign” at the Vet BLUE® Caudodorsal view. In this Global FAST® order, the HR5th Bonus view is on its own so to speak and not associated with the first 4 AFAST® views – DH, SR, CC, SIU – of the AFAST® abdominal fluid scoring system. The HR5th Bonus view is still scored, but not part of the overall abdominal fluid score (AFS) total; and the HR5th Bonus view is interrogated for any soft tissue abnormalities of the right kidney and adjacent right liver. Lastly, this view is never performed by running the probe underneath the patient because of the discomfort to the patient, and the pressure placed in that region that can push structures and free fluid out of the scanning plane.
Send your comments to Dr. Greg Lisciandro, Dipl. ABVP, Dipl. ACVECC at LearnGlobalFAST@gmail.com
gl/GL 1-21-2025
