American Association for the Surgery of Trauma Grade 4 Renal Injury Substratification Into Grades 4a (Low Risk) and 4b (High Risk)

Abstract

On radiography a large perirenal hematoma, intravascular contrast extravasation and medial renal laceration are important risk factors associated with the need for urgent hemostatic intervention after renal trauma. Assessing these computerized tomography characteristics collectively shows that American Association for the Surgery of Trauma grade 4 renal injuries can and should be substratified into grades 4a (low risk) and 4b (high risk).

Grade IV renal trauma management. A revision of the AAST renal injury grading scale is mandatory

“…Thus, Dugi et al [26], from Parkland Hospital (USA), reviewed patient records with grade III and IV renal injuries that came to their trauma center and identified, blinded to clinical outcomes, computerized tomography findings associated with the need for urgent intervention for haemostasis. A large perirenal hematoma greater than 3.5 cm, intravascular contrast extravasation and medial renal laceration were important risk factors associated with the need for urgent haemostatic intervention.…”

Urotrauma: AUA Guideline

“…34 This injury grading scale has been validated as predictive of morbidity and need for intervention to treat higher grade injuries. 35-37 The system has ambiguity when staging high-grade injuries, 38 however, and several authors have proposed modification of this grading scale to better guide therapy 39 or to address ambiguity in staging injuries. 40 There has been no formal revision of the AAST injury scale.…”

Computed tomographic imaging in determining the need of embolization for high-grade blunt renal injury

“…7 Nuss et al 15 demonstrated that a PRD of greater than 4 cm combined with CE was associated closely with the need for TAE. Dugi et al 17 and Charbit et al 16 reported similar results using a different cutoff value for PRD. According to our analysis, although PRD correlated with the need for TAE and the combination of PRD with either CE or extent of hematoma or both increased PPV and NPV, none of these criteria were better for predicting the need for TAE compared with the combination of CE and extent of hematoma.…”

“…16,17 Shanmuganathan et al 19 demonstrated that active bleeders can be missed when using suboptimal CT contrast medium enhancement techniques. Furthermore, transient hemostasis can be found on CT and angiography and may be disrupted by increased blood pressure during resuscitation that causes rebleeding.…”