1. Chapter 72: Abdominal Vascular Injuries
October 24, 2005

2. Abdominal trauma zones

3. Trauma algorithms

6. Damage control procedures
Persistent attempts to reconstruct or repair all abdominal injuries may result in increased mortality
‘damage control’ approach
All complex venous injuries are ligated
Arterial injuries may be shunted
Any diffuse retroperitoneal or parenchymal bleeding is controlled by tight gauze packing

7. Abdominal compartment syndrome
Normal pressure resting supine is near zero
Elevation of pressure above 25 to 30 cm of water may cause severe organ dysfunction
Abdominal compartment syndrome characterized by
Tense abdomen
Tachycardia with or without hypotension
Respiratory dysfunction with high peak inspiratory pressures
Oliguria
Risk factors
Massive blood transfusions
Prolonged hypotension
Hypothermia
Aortic cross clamping
Damage control procedures
Tight closure of abdominal wall

8. Abdominal compartment syndrome
High risk patients can be followed with clinical exam and serial bladder pressure measurements
Pressures greater than 30 indicate need for surgical decompression of abdomen
Temporary abdominal wall closure can be performed with large dialysis bag or synthetic mesh
When bowel edema improves several days later the abdomen can be closed

9. Abdominal aortic injuries
Blunt injury is rare 0.04% of all blunt trauma admissions
Intimal dissections and thrombosis most common lesions
Penetrating trauma more likely
2.7% of gunshot wounds to abdomen
1.5% of knife wounds to abdomen
21% of all abdominal vascular injuries, second most commonly injured vascular structure

10. Abdominal aortic injuries
Operative exposure by medial visceral rotation

11. Celiac artery injuries
Rare, 302 cases of vascular injury, the celiac artery was involved in 3.3% of cases
Operative exposure through lesser sac or medial visceral rotation, this does not need to include the left kidney
Ligation is tolerated well secondary to rich collateral blood supply
Mortality ranges from 38 to 75%, probably secondary other concominant injuries

12. SMA injuries
Zone 1 aortic origin to inferior pancreaticoduodenal artery
Zone 2 to the middle colic artery
Zone 3 distal to middle colic artery
Zone 4 segmental intestinal branches
Ligation of SMA in zones 1 and 2 results in severe ischemia of small bowel and right colon
Ligation of SMA in zones 3 and 4 may result in localized ischemia

13. SMA injuries
Penetrating injuries are the most common mechanism of injury
SMA injuries diagnosed in 0.09% of trauma admissions and account for 10% of all abdominal vascular injuries, Asensio Am J Surg.
Blunt trauma responsible for 10 to 20% of these injuries

14. SMA injuries
Any hematoma injury involving bowel ischemia should be explored
Author does not explore stable hematomas if the bowel is not compromised, they are followed post-operatively by angiography or doppler ultrasound
Sharp partial transections can be managed by lateral arteriorrhaphy in 40% of cases
Mobilization of SMA made difficult by surrounding dense neuroganglionic tissue and multiple branches, thus end to end anastomosis rarely possible
Ligation of SMA below middle colic artery associated with moderate risk of bowel ischemia

15. SMA injuries
Ligation of SMA proximally only in the presence of necrotic bowel, otherwise may result in short bowel syndrome
In critical ill patients with hypothermia, acidosis, and coagulopathy a damage control procedure with a temporary endoluminal shunt may be performed
Later reconstruction may be performed with saphenous vein or PTFE from the aorta, if there is any associated pancreatic injury all attempts should be made to keep the anastomosis away from the pancreas and should be protected by omentum and soft tissue
Some authors mandate a second look operation in 24 hours, others look for persistent metabolic acidosis despite adequate fluid hydration

16. SMA injuries
Reported mortality with SMA injuries varies from 33 to 68% in multiple series
This is difficult to assess as patient typically have multiple other associated injuries

17. IMA injuries
Rare and almost always due to penetrating traumas, 1% of all abdominal vascular injuries
Ligation is well tolerated with no cases of colorectal ischemia have been reported in trauma

18. Iliac vascular injuries
Low reported incidence from WW2, Korean war and Vietnam war, 1.7 to 2.6%
Urban trauma centers report 10% of all abdominal vascular injuries for both arteries and veins
26% have combined injures
Penetrating trauma involves common iliac vessels
Blunt usually involves branches of internal iliac artery
Also pelvic fractures can directly tear iliac vessels or result in stretching of the vessel resulting in intimal tear and subsequent thrombosis

19. Iliac vascular injuries
Blunt trauma explore if
Intraperitoneal leak
Expanding hematoma
Absent or dimished femoral pulse
Penetrating trauma should be explored
Ureter should be identified and protected
Avoid iatrogenic injuries to underlying vein
Isolation and control of internal iliac artery important even proximal and distal control is present
If exposure is difficult an additional transverse lower abdominal incision or longitudinal groin incision can be made

20. Iliac vascular injuries
Small arterial injuries can be repaired with 4-0 and 5-0 sutures
Venous or PTFE patch can be used to avoid stenosis
With most gunshot wounds and blunt trauma, reconstruction by an end to end anastomosis can be undertaken size 6 to 8mm
Balloon tipped catheter should be passed proximally and distally to remove clots
Author recommends local heparin, role for systemic heparin?
Author suggests no significant role for extraanatomic bypasses in trauma
Burch (Trauma 1990) suggests that enteric spillage is not a contraindication to prosthetic graft

21. Iliac vascular injuries
Ligation of the common or external iliacs a bad choice
Instead a temporary intraluminal shunt should be used
Author believe transection of the right common iliac artery to gain better access to the iliac veins is “extreme and should rarely be considered.”
Instead careful mobilization and retraction of the artery should be performed
Ligation and division of the internal iliac artery may also be helpful
Ligation of an iliac vein is preferable to a repair that causes stenosis that can lead to thrombosis and pulmonary embolism
Role of filters in narrowed iliac veins yet to be determined
Patient tend to develop transient leg ischemia

22. Iliac vascular injuries
Many patients develop compartment syndrome of their extremities and require fasciotomies
Role of prophylactic fasciotomies controversial
If fasciotomy is not performed, close clincal examination and pressure measurements are warranted
Mannitol may be useful to reduce effects of reperfusion injury and inhibiting the development of compartment syndrome

23. Renovascular injuries
16% of all abdominal vascular injuries
Left renal artery 1.3 to 1.6 times more likely to be injured than right renal artery, thought to be due to its course underneath IVC
50% of cases of blunt arterial injury result in intimal tears and subsequent arterial thrombosis
12% of cases involve avulsion
9 to 14% of cases involve both arteries
When possible abdominal CT scan a very good diagnostic tool

24. Renovascular injuries
For penetrating injuries generally reconstruction or nephrectomy is performed depending on extent of injury
All zone 2 hematomas secondary to penetrating injury should be explored
Blunt trauma is very time dependent
Renal function severly affected after three hours of total ischemia and six hours after partial ischemia
More aggressive approaches to those with bilateral injuries or those with injuries to a solitary kidney, some authors have attempted revascularization up to 20 hours after initial injury
Cumulative success of revascularization is 28% with subsequent hypertension developing in 12 to 58% of patients
32 to 40% of patient managed non-operatively develop renovascular hypertension

25. Renovascular injuries
Ligation of the left renal vein well tolerated near IVC because of drainage through left gonadal vein, left adrenal vein and lumbar veins
Ligation of the right renal vein should be followed by nephrectomy
Endovascular techniques useful to treat selected cases of intimal tears, false aneurysms, and AV fistulas

26. IVC injuries
Most commonly injured abdominal vessel accounting for 25% of all injuries
Blunt trauma account for 10% of these injuries and typically retrohepatic
With penetrating injuries also 18% of patients have associated aortic injury
All hematomas secondary to penetrating trauma should be explored, except for stable retrohepatic hematomas
Infrarenal/juxtarenal IVC best exposed by medial rotation of the right colon, hepatic flexure of colon, and duodenum
Exposure of retrohepatic IVC by dividing ligaments, extending incision to include right subcostal
Median sternotomy if atriocaval shunt is planned

27. IVC injuries Hepatic vascular isolation Atriocaval shunt
Cross clamping infradiagphragmatic aorta, suprahepatic IVC, infrahepatic IVC above renals, and portal triad
Failure to clamp aorta first may result in severe hypotension and then cardiac arrest due to reduced venous return
Atriocaval shunt
Typically with poor results but some case reports describe some successes

28. IVC injuries
Liver can be divided along gallbladder IVC plane to provide direct exposure
Most IVC injuries repaired with 3-0/4-0 prolene
Cava can be rotated to expose posterior injuries
With anterior and posterior injuries, the posterior injury can be repaired through the anterior injury (can also be lenghtened)
Ligation can be considered above the renal veins in very unstable patients or those with significant stenosis after repair
Post-op patient should have lower extremities wrapped in firm elastic bandages and elevated, edema usually subsides in several weeks
Patients may develop compartment syndrome and require fasciotomies

29. IVC injuries Mortality
Half of patients with IVC injuries die before reaching the hospital
Those reaching the hospital have reported survival rates of 20 to 57%
Kuene (Am Surg, 1999) reported an overall mortality of 52%, the mortality decreased to 35% if the patient reached the operating room
Associated higher mortality with suprarenal injuries

30. Portal vein system injuries
Injury is very rare, about 1% of those patients undergoing laparotomy for trauma
About 5% of abdominal vascular injuries
SMV injuries about 11% and splenic vein about 4% of abdominal vascular injuries
Majority of portal vein injuries secondary to penetrating trauma 90%
Associated vascular injuries reported to be high, 70 to 90% due to anatomy

31. Portal vein system injuries
Blunt trauma usually involves SMV and direct blow to abdomen or deceleration forces
Results in thrombosis of vessels and sometimes avulsion and bleeding
With isolated thrombosis, diagnosis made on CT scan
Stapled division of the pancreatic neck should be considered early
Suprapancreatic portal vein exposure by medial rotation of right colon and hepatic flexure and a Kocher maneuver

32. Portal vein system injuries
Portal vein injuries should be repaired with lateral venorrhaphy
Complex reconstructions often fail and only undertaken if hepatic artery is out
Ligation of both hepatic artery and portal vein is not compatible with life, in this case reconstruction of the portal vein should be undertaken with saphenous vein
Ligation of the portal vein with an open hepatic artery survival ranges from 55 to 85%
Patients with ligated SMV or portal veins will need further attention
Bowel will become massively edematous resulting in abdominal compartment syndrome, thus the abdomen should not be closed
Can develop patch bowel wall necrosis and a re-look operation should be performed in 48 to 72 hours
Patients require massive fluid replacement
Long term evidence is limited but survivors do not develop portal hypertension

33. Portal vein system injuries
Mortality is high and ranges between 50% to 72%

34. Advances
Introduction of the policy of scoop and run in addition to early surgical control of bleeding is now standard of care
Concept of damage control
Recognition of abdominal compartment syndrome and use of temporary prosthetic
Endovascular techniques to specific vascular occlusions, av fistulas and false aneurysms