Abdominal & GU Trauma

1. Abdominal & GU Trauma October 10, 2002 Moritz Haager Dr. Michael Betzner

2. Objectives • Anatomical review • Examine relationship between mechanism of injury, and resultant injury patterns • Review diagnostic & therapeutic options • Develop an approach to abdominal trauma

3. My 2 ¢.. • Trauma is highly variable in presentation, extent of injury, and examination • Easy to lose sight of the forest for the trees • A structured (i.e. ATLS) approach helps • 3 ideas to keep in mind: • Clinical suspicion avoids missed injuries • Frequent reassessment avoids missed injuries • Know the limitations of your tests

4. Case • 22 yo male, roll-over MVA • GCS 12, HR 120, BP 100/60, RR 24 • CHI, RUQ contusion, obvious R lower leg # • Resuscitated with 2L NS, vitals improve to GCS 12, HR 80, BP 115/70, RR 18 • CT shows grade IV liver lac’n • Does he need OR?

5. Anatomy 101 • Ant abdomen: • nipple line • ant axillary lines • inguinal ligaments • Flank: • 6th ICS  iliac crest • Ant  post axillary line • Back: • Tip of scapulae  iliac crest • Post axillary lines

6. Abdominal Cavities • Peritoneum: • Upper: liver, spleen, diaphragm, stomach, transverse colon • Lower: small bowel, sigmoid colon • Retroperitoneum: • Abd aorta, inf vena cava, duodenum, pancreas, kidneys, ureters, ascending / descending colon • Pelvis: • Rectum, bladder, iliac vessels, internal genitalia

7. Blunt Abdominal Trauma • Blunt mechanism accounts for >94% injury (pediatric + adult) locally • Higher mortality • Difficult Dx • Usually multi-system / multi-organ injury • MVA is leading cause (52.4% adult, 46.2% peds) • Falls (~25%), and violence (~7%) • CRHA Regional Trauma Services Annual Report 2000-2001 • 3 mechanisms: • Deceleration / compression • Crush injury • Shearing / avulsion

8. History • AMPLE Hx • Mechanism of injury: • Penetrating vs. blunt • MVA: • Speed • Type (roll-over, rear-end, frontal, etc) • Restraints / air bags • Damage / intrusion • Status of passengers

9. Exam • ABC’s / Primary Survey • Inspection: • Abrasions, contusions, lacs, penetrating wounds, impaled FB’s, evisceration, pregnancy, blood at urethral meatus, scrotal / perineal ecchymoses • Auscultation: • BS yes or no • Percussion / Palpation: • Peritoneal findings • Pelvis stable • Prostate postion • Accuracy of exam in BAT is 55-65%

10. Injury patterns in BAT • Spleen is most commonly injured organ • Seatbelt injuries • Rib fractures • Abdominal injuries • Mesenteric lacerations  hemoperitoneum • Bowel contusions / perforations  delayed S/S • Diaphragmatic rupture • Abd aortic dissection (rare) • Iatrogenic • Ventilation  GI distention / rupture • CPR  solid organ injury • Tube thoracostomy  solid organ injury

12. Name 6 differences in BAT in kids • Weaker abdominal musculature & less fat • Smaller AP diameter • Major organs in close proximity • Compliant rib cage • Previously undiscovered disease • E.g. coagulopathies • Occult non-accidental trauma (= #1 cause of death in > 1 yo age group) • Bottomline: • Increased risk for multi-organ injury

13. Blunt Trauma Algorithm:

14. Approach to BAT • “the abdomen should neither be ignored nor the sole focus of the EP”Rosen • Diverse spectrum of possible injury in BAT therefore clinical suspicion is key • Answer a series of questions: • Are there clinical indications for immediate OR? • Is the patient hemodynamically stable? • Is the exam reliable? • Is there evidence for intraperitoneal injury, and if so does it require operative intervention?

15. Indications for Laparotomy • Unexplained hypotension / evidence for bleeding • Clear, persistent peritoneal irritation • Pneumoperitoneum • Diaphragmatic rupture • Persistent significant GI bleeding

16. Hemodynamically stable? • No • seek IPH with DPL or U/S • CXR and AP pelvis for non-peritoneal causes • Laparotomy if IPH • Yes • Seek intraperitoneal injury • Diagnostic imaging vs. serial exams • Operative vs. non-operative management

17. Unstable pt None CXR, AP pelvis DPL FAST Role of the “trauma panel” Stable pt CT FAST DPL Serial exams MRI ERCP Radionuclide studies Contrast studies Angiography Investigations in BAT

18. The Trauma Panel • What’s usually ordered: • CBC, ‘lytes, Cr, BUN, PT, PTT, T /S, T/C, UA, EtOH, ABG, • What there is actually evidence for: • Mostly retrospective studies • Most demonstrate abnormalities, but fail to indicate any change in management • Review concludes most useful tests are T/S, T/C, CBC, PT/PTT , ABG, and tox screen • Asimos. Emerg Med Reports. 1997

19. Plain Radiography • CXR • Ruptured hemidiaphragm, pneumoperitoneum, loss of psoas shadow, retroperitoneal air • AP Pelvis • Pelvic fracture • Routine use in awake pt with stable, non-tender pelvis may be unnecessary • AXR • Not routinely indicated in BAT • May show tract, or retained missiles in PAT

23. Diagnostic Peritoneal Lavage • “virtue is in the triage of the patient who is hemodynamically unstable and has multiple injuries……especially valuable in the discovery of potentially lethal bowel perforations”Rosen • Sens 98-100%, Spec 90-96%, Acc 98-100% • Positive DPL in setting of BAT: • Aspiration of > 10 ml gross blood • > 100,000 RBC/mm3 • > 500 WBC/mm3 • Bile, bacteria, vegetable matter, or inc’d amylase levels

24. Diagnostic Peritoneal Lavage • Advantages • Rapid • Aids operative decision-making • Good for detecting hollow viscus injury • Disadvantages • Samples only peritoneal cavity • Invasive • False positive rate of 2% (Inc’s laps) • Non-specific

25. Computed Tomography • Test of choice in STABLE pts • Advantages: • Defines location and extent of injury • Ability to image multiple areas accurately • Aids in non-operative management • Disadvantages: • Insensitive for pancreatic, diaphragmatic, and bowel injuries • IV contrast • Not suitable for unstable pts

27. FASTFocused Assessment w/ Sonography for Trauma • Rapid U/S exam focusing on: • Pericardium • Perihepatic: Morrisons Pouch • Perisplenic: Splenorenal recess • Pelvis: Pouch of Douglas (♀), rectovesicular pouch (♂)

28. FAST • Advantages: • Rapid (<5 min), non-invasive, bed-side • Sensitivity close to DPL • Can follow w/ serial exams • Disadvantages: • Poor imaging of retroperitoneum, diaphragm, bowel, or solid organ damage • Technically difficult in agitation, obesity, or bowel gas; operator dependent • Sensitivity in kids < adults

29. FAST • How to interpret a study: • Positive: • fluid in pericardium or any 1 of 3 abdominal windows • Negative: • No fluid in any windows • Indeterminate: • If any one of the 4 windows is inadequately visualized

30. Normal study Hemopericardium

31. Perisplenic fluid Normal Study Perihepatic fluid

32. FAST • How good is it? • Hemoperitoneum (Sens: 78-99%, Spec: 97-100%) • Hemopericardium (Sens: 100%, Spec: 97%) • Assumes important injuries will have ass’d free fluid • However recent meta-analysis found NPV for IPFF and organ injury to be 0.78-0.94 + 0.72-0.99 respectively • By calculating LR’s this means assuming pre-test prob of 50%, the post-test prob after –ve FAST remains 25% • Concluded that a negative study does not adequately exclude IP injury • Stengel et al. Br J Surg. 88: 901-912. 2001 • Not adequately studied in pediatric trauma • Jones. Trauma Reports. 2000

33. Should we learn to FAST? • U/S training mandatory as part of surgical residency in Germany • FAST consensus committee recommends incorporation into residency training • Studies have shown easy to achieve competency in detecting free fluid • Jones. Trauma Reports 2000 • No sig differences noted b/w experts & beginners in detecting FF • Stengel et al. Br J Surg. 88: 901-912. 2001

34. Others • Contrast Studies: • Gastrograffin for bowel perforations • Urethrogram / retrograde cystogram • Angiography • Localization of bleeding / embolization • ERCP • delineation of pancreatic injury / stent placement • MRI • Spinal fractures, diaphragmatic defects • Radionuclide • Solid organ imaging if CT unavailable

35. BAT Management • Boils down to who needs urgent OR and who can be observed • Laparotomy for all used to be standard • Non-operative management increased from 10% to 54% over 6 year period in one study • Schwab. World J Surg. 25: 1389-92. 2001 • Really a surgical decision, but we need to understand what Kortbeek and Co are doing and why

36. BAT: Why NOT operate? • Non-therapeutic laparotomy rate 14-27% if indications just based on DPL + physical exam • ↓’g number of non-therapeutic laps ↓’s morbidity + mortality • Avoids 2nd hit hypotension • Some injuries appear to do better w/o OR • Improved tools to monitor pts • Schwab. World J Surg. 25: 1389-92. 2001

37. BAT: Non-operative Management • Factors no longer felt to represent absolute indications for OR: • Advanced age • Grade of solid organ injury* • Initial BP • Hemoperitoneum (presence or size) • Altered mental status • Schwab. World J Surg. 25: 1389-92. 2001

38. BAT: Non-operative Management • Who is NOT a candidate? • Hemodynamically unstable • Acute abdomen / peritonitis • Hollow viscus injury • Evidence of intraabdominal injury requiring operative repair on CT • Ochsner. World J Surg. 25: 1393-96. 2001 • “The patient who is best served by early celiotomy…is one who cannot be stabilized with volume infusion.” • Schwab. World J Surg. 25: 1389-92. 2001

39. BAT: Non-operative Management • Who is likely to fail non-operative mgmt? • Hemodynamic instability despite resuscitation* • Contrast blush on CT* • Contrast pooling on CT* • ?Grade IV-V liver injuries • ?Grade IV and higher splenic injury • ?Increasing size of hemoperitoneum • Further prospective evaluation is needed • Ochsner. World J Surg. 25: 1393-96. 2001

40. Non-operative Mgmt: Liver • In general CT appearance of solid visceral injury correlates poorly with need for OR • Contrast pooling strongest predictor for OR • Non-operative mgmt expected to be successful in 90% of hemodynamically stable pts with documented liver injury • Mandates very close F/U with serial exams • Pitfalls: • Missed co-existant injuries req’g OR • Attributing ongoing blood loss to other sources • Transfusing > 4 U PRBC’s • Misinterpreting CT scan • Kimball. World J Surg. 25: 1403-04. 2001

41. Non-operative Mgmt: Spleen • Why not splenectomize? • OPSI: 80% mortality, life-long risk • Clear association b/w grade of splenic injury and increased rate of operative intervention • I , II  non-operative Tx • ~90% w/ 10-20% failure rate • F/U CT scan at 6-8 wks • III, IV  partial resection, mesh splenorraphy • V  splenectomy • CT findings indicating need for OR controversial • Contrast blush most consistent • Angiography + embolization evolving • Uranüs and Pfeifer. World J Surg. 25: 1405-07. 2001

42. Penetrating Abdominal Trauma • US data: GSW’s account for 90% of penetrating trauma mortality despite stab wounds being 3x as common • Locally penetrating trauma (all types) accounts for 3-5% of injuries • Only 2 cases of assault with firearm in ‘00-’01 in Calgary • No pediatric penetrating trauma in ’00-’01 • CRHA Regional Trauma Services Annual Report 2000-2001

43. My view on gun control:

44. ..and the NRA perspective:

45. Penetrating Abdominal Trauma • Pathophysiology: • Stab wounds: • Knives, fences, horned animals • Most do NOT enter peritoneal cavity • Liver > small bowel > other injuries • IP injury related to site of stab wound • Missiles: • Bullets, explosions, machinery-related accidents • Multiple IP injuries are the rule • Small bowel > colon > liver > other • Impact velocity is primary determinant of severity • BAT + PAT may coexist e.g. Pine Lake

46. Penetrating Abdominal Trauma • What do you want to know? • Stab wounds: • Cause of wound • Number + location of wounds • Body position at time of injury • Time of injury, EBL at scene, response to Tx • GSW’s / Missiles: • Type of weapon or missile • Distance from the victim

47. Initial Management + Evaluation • ABC’s / Primary survey • Early antibiotics for suspected bowel perf’n • Management depends on mechanism: • GSW: any torso GSW presumes IAI • Stab: often stable w/ equivocal exam • Unstable + peritoneal findings  OR • Stable • Objective is to utilize diagnostic studies to determine if peritoneal penetration occured

48. Investigations • Trauma panel • Plain films • DPL • FAST • CT • Local Wound Exploration • Laparoscopy

49. DPL • Same technique and diagnostic criteria as in BAT, except RBC criteria depending on location:

50. Local Wound Exploration • Primary use in single anterior stab wounds to r/o peritoneal penetration • Not used in: • Multiple stab wounds • entry over thorax • Inability to clearly visualize end of wound tract presumes peritoneal violation