> [!Key Points] > 1. can detect arterial bleeding on portal venous study > 2. when you find an injury in one area, look around the rest of the corridor of impact for other injuries > 3. mesenteric free fluid suggests bowel injury and needs laparotomy > 4. Bladder can rupture interperitoneal and extra-peritoneal > 5. consider any [[Pelvis trauma radiology#Sources of bleeding|pelvic trauma with bleeding]] if finding extra-peritoneal blood # Contrast choices - **portal venous** generally most appropriate for abdomen imaging - can still see arterial bleed if **dense conrast blush** -- you've actually given more time for conrast to leak out than on the arterial phase - arterial contrast generally used for [[Chest trauma radiology]] to best visualse aortic injuries and outline the aorta - arterial in abdomen makes it difficult to look for contusions and lacerations in spleen - makes it difficult to detect laceration in liver on pure arterial phase ## examples ![[Pasted image 20230420150812.png]] ^ liver laceration much more obvious on portal venoush phase than arterial phase example 2: ![[Pasted image 20230420151204.png| small bright spot in arterial phase of liver laceration. parenchyma hypodense compared to rest of liver]] ![[Pasted image 20230420151419.png|portal venous of same injury, laceration more obvious, and more dense contrast leak]] ## Dual bolus CT - split contrast boluses -- chest and abdomen in 1 run. - less radiation because don't need to scan chest and liver section twice - dual bolus protocol - in shocked trauma patient, likely should do two dedicated studies # Solid organ injury ![[Pasted image 20230420152317.png]] ## Parenchyma ### Laceration **Laceration** - linear defect through organ, usually hypoattenuating compared to normal parenchyma. can be stelate. ![[Pasted image 20230420152651.png|note perinephric haematoma, rather than black surrounding cortex]] ![[Pasted image 20230420152932.png|stelate liver laceration, note haemoperitoneum around site of injury with higher density fluid, called "sentinel clot" which suggests it is coming from this organ]] ### Contusion - microbleeds in organ, get ill-defined hypotenuation in organ ![[Pasted image 20230420153237.png| note ill-defined hypoetenuation in kidney, also note peri-nephric haematoma not distorting contour of kidney. This is important for differentiating peri-nephric from subcapsular haematoma]] ### Subcapsular haematoma >[!Tip] definition >**subcapsular haematoma** - distorting contour of organ ![[Pasted image 20230420153513.png]] ^ obvious bleed around the kidney **distorting the contour** ![[Pasted image 20230420160129.png| note large subcapsular haematoma distorting the contour of the liver. Secondary to large laceration through middle of liver (see mouse pointer)]] ## Vascular injury ### active bleeding - mentioned in discussion of portal-venous vs. arterial phase above - river of conrast heading into a large haematoma - if river of contrast without haematoma, then consider [[#AV fistula]] ![[Pasted image 20230420160731.png]] ![[Pasted image 20230420160858.png]] ^ large peri-splenic haematoma, contrast moving away into haematoma ### pseudoaneurysm **pseudoaneurysm** - damage vessel wall, but adventitia and connective tissue allows it to stay together. may have an out-ouching, but doesn't need to be associated with large haematoma. However, it is ==at risk of becoming an active bleed. == > can use the term "contrast blush" if unclear whether active bleeding or pseudoaneurysm ### AV fistula - river of contrast out of artery but not much haematoma around it - can be caused by trauma - common in penetrating injuries (eg vertebral artery into jugular )--> can cause steel phenomenon ### devascularisation ![[Pasted image 20230420162705.png]] ^ kidney itself looks ok, but not enhancing, so likely the **origin of blood supply** is injured eg at aorta. lots of posterior renal space haematoma noted. ## Special fluid ### Bile leak - low density fluid developing near liver laceration after a few weeks - often treated conservitavely initial CT: ![[Pasted image 20230420184506.png]] ^ note laceration to liver 7 days later: ![[Pasted image 20230420184624.png]] ^ now has a collection of fluid near where the laceration was, same density as gallbladder. fluid is a **biloma** ### Urinoma - if you lacerate kidney, can lacerate renal collecting system, causing urinoma - need delayed phase contrast after first ct to see if contrast leaking out from kidney (stay on CT table for it - most common complication of renal trauma (7.5% of patients) ![[Pasted image 20230420180942.png]] ![[Pasted image 20230420181355.png]] ^ Gunshot wound going through left kidney, causing a urinoma ## Blunt splenic injury **Eastern trauma association recomendations** : - any patient with diffuse peritonitis or haemodynamically unstable warrants urgent laparotomy - Level 1 evidence - stable patient or fluid-responsive with AAST grade IV & V, contrast blush, moderate haemoperitoneum, or ongoing splenic bleeding, to consider angiography +/- embolisation (rather than embolisation) - Level 2 evidence ## pancreatic and duodenal injury ![[Pasted image 20230420214450.png]] ^ bleeding into lesser sac with haematoma and sentinel clot pushing pancreas out of the way ![[Pasted image 20230420214637.png|laceration through pancreas]] - rare injury - pancreatic trauma has high morbidity and mortality (mortality ~20%) # Traumatic Abdominal fluid ## Detection - can use FAST scan of course ![[Pasted image 20230420185258.png]] - fluid in lesser sac rare due to anatomy, implied injury to pancreas or duodenum if found here - greater sac usually fills with fluid with liver or spleen laceration **Places to look for free fluid:** (note, this is a normal CT) ![[Screen Shot 2023-04-20 at 6.56.37 PM.jpg]] ![[Pasted image 20230420190050.png|Morrison's pouch (empty here)]] ![[Pasted image 20230420190144.png|normal paracolic gutter]] ![[Pasted image 20230420190229.png]] ^ interperitoneal fluid will sit above seminal vesicles anterior to the rectum in male patient. fluid posterior to the rectum would be extra-peritoneal fluid. anterior to the bladder would also be extra-peritoneal. ==Bladder rupture can cause both interperitoneal and extraperitoneal fluid== **bladder rupture factoids:** - extraperitoneal bladder rupture more common than interperitoneal bladder rupture. - cystography to review for this - extraperitoneal bladder rupture treated conservitively with IDC; interperitoneal surgically ### Examples of free fluid on CT from splenic bleed ![[Pasted image 20230420190506.png]] ^ fluid in front of liver and lateral to liver, not behind liver ![[Pasted image 20230420190541.png]] ^ obvious haemoperitoneal next to liver and spleen (note shattered spleen) ![[Pasted image 20230420190645.png]] ^ zoomed in, good example of ==sentinel clott== in the higher density areas compared to the lower density around liver, suggesting bleeding source from spleen ![[Pasted image 20230420190932.png]] ^ paracolic gutter with fluid on both sides ![[Pasted image 20230420191059.png]] ^ pelvis with free fluid anterior to rectum and superior/posterior to bladder (hard to see because essentially same density as bladder) - in spite of large volume of free fluid, no free fluid was found in small bowel mesentery ### Sentinel clot near liver but mesenteric injury ![[Pasted image 20230420191402.png]] ^ note multiple densities on right ![[Pasted image 20230420191603.png]] ^ note **triangles** of fluid in small bowel: abnormal. concern for mesenteric injury, needs urgent trauma laporotomy! ![[Pasted image 20230420191731.png]] - jejunum most common site of bowel injury # Free gas - turn on bone window to see it - note, do **not** need to have free gas to have injured mesentery; sometimes small bowel is mostly fluid ![[Pasted image 20230420212546.png| free gas under umbilicus from traumatic bowel injury]] # Shocked bowel - enhancing mucosa of walls of bowel, gall bladder, oedema, peri-portal oedema - CT hypoperfusion - usually due to profound hypotension injury - in recovery phase get hyperperfusion of mucosa ![[Pasted image 20230420212919.png| note vivid enhancement of mucosa]] # Grading scales ## AAST splenic injury - **grade I** - subcapsular haematoma <10% surfance area - parenchymal laceration <1cm depth - capsular tear - **grade II** - subcapsular haematoma 10-50% surfance are - intraparenchymal haematoma <5cm - parenchymal laceration 1-3 cm in depth - **grade III** - subcapsular haematoma >50% of surface area - ruptured subcapsular or intraparenchymal haematoma >5cm - parenchymal laceration >3cm in depth - **grade IV** - any injury in the presence of a splenic vascular injury or active bleeding, confined within splenic capsule - parenchymal laceration involving segmental or hilar vessels producing >25% devascularisation - **grade IV** - shattered spleen - an injury in the presence of splenic vascular injury with active bleeding extendin beyond the spleen into the peritoneum ## AAST liver injury scale |grade| injuries| treatment| |---|---| ---| |I | haematoma subcapsular <10% surface area| | |II| haematoma 10-50% surface area| | |III| haematoma subcapsular >50% surface area of ruptured haematoma| | |IV| laceration: parenchyma disruption involving 25-75% of hepatic lobe, vascular injury with active bleeding contained within lier parenchyma| | |V|juxtahepatic venous injuries, parenchymal disruption >75% hepatic lobe| | # other considerations ## IVC filder - can be considered in high risk patents (not an ED issue !!) for VTE who cannot be anticoagulated - remove filter at 6 months #trauma #radiopaedia