1. Abdominal Trauma Cindy Kin Trauma Conference 8 January 2007 Stanford General Surgery

2. Blunt Abdominal Trauma Mechanisms Direct impact Acceleration-deceleration forces Shearing forces No correlation between size of contact area and resultant injuries. Abdomen = potential site of major blood loss.

3. Initial Evaluation and Treatment Is there a surgical intraabdominal injury? PE: guarding, peritoneal signs, tenderness, nausea. DRE. Lower rib fxs: 10-20% a/w spleen/liver injury Seatbelt sign a/w intestinal injury and mesenteric tears. Direct blunt trauma: rupture/tear of solid organs. Flank pain or contusion often late signs of retroperitoneal bleed Rapid resuscitation CXR, Pelvic X-ray FAST v DPL v CT Labs: Hct, WBC, amylase, UA, ABG, T+C

4. Blunt Abdominal Trauma INDICATIONS for CT Blunt trauma with closed head injury Blunt trauma with spinal cord injury Gross hematuria Pelvic fx, +/- suspected bleeding Pt requiring serial exams, but will be lost to PE for prolonged period (ie orthopedic procedures, general anesthesia) Pts with dulled or altered sensorium CONTRAINDICATIONS: unstable patients

5. Blunt Abdominal Trauma CTFASTDPL Accuracy96%95-99%95% Sensitivity97%90-92%100% Specificity95%88-90%85% DrawbacksStable pts only Cannot evaluate retroperitoneum. Cannot identify source of fluid. 0.5% miss intestinal perforation; cannot distinguish blood v bowel contents

6. Blunt Abdominal Trauma Shock with expanding abdomen, pnemoperitoneum, retroperitoneal air INDICATIONS FOR LAPAROTOMY Imaging: CXR FAST/DPL/CT Stable w/ peritoneal signs Peritoneal signs, HD unstable, sepsis + equivocal Observe, +/- re-image

7. Blunt Abdominal Trauma ROLE OF DIAGNOSTIC LAPAROSCOPY Hemodynamically stable patients Inadequate/equivocal FAST or borderline DPL (80K-120K RBC/HPF) Intermittent mild hypotension or persistent tachycardia Persistent abdominal signs/symptoms Potential to decrease # of nontherapeutic laparotomies

8. Blunt Abdominal Trauma PREDICTIVE VALUE OF QUANTIFYING BLOOD VOLUME ON FAST EXAM Hemoperitoneum score on ultrasound a better predictor of need for therapeutic laparotomy than admission blood pressure and/or base deficit. Hemoperitoneum characterized by measurement and distribution, scored Ultrasound score >=3 statistically more accurate than combination of SBP and base deficit in determining which patient will undergo a therapeutic abdominal operation 83% sensitivity, 87% specificity, 85% accuracy –McKenney et al, J Trauma 50:650-656, 2001

9. Blunt Abdominal Trauma HEPATIC AND SPLENIC INJURIES Unstable patients: mandatory laparotomy Stable patients: selective nonoperative approach Hepatic injury -Usually venous bleeding -Grade I-III: 94% success w/ nonop treatment -Grade IV-V: 20% amenable to nonop tx -HD stability, stable Hct, observation -Complications: delayed hemorrhage, bile leak, biloma, intra/peri hepatic abscess. -If stable with ongoing bleeding - angiographic embolization

10. Blunt Abdominal Trauma SPLENIC INJURIES Often arterial hemorrhage, therefore nonoperative management less successful. Predictive factors for nonop success: –Localized trauma to flank/abdomen –Age<60 –No associated trauma precluding obs –Transfusion <4u prbcs –Grade I-III Grade IV-V: almost invariably require operative intervention Delayed hemorrhage (hours to weeks post-injury): 8-21%

11. Blunt Abdominal Trauma RETROPERITONEAL HEMORRHAGE Source: aorta, IVC, kidneys and ureters, pancreas, pelvic fx, retroperitoneal bowel. Minimal signs on examination; flank pain and contusion are late findings FAST/DPL negative; CT can identify

12. Blunt Abdominal Trauma DUODENAL AND PANCREATIC INJURY Subtle diagnosis: amylase abnl, obliteration of R psoas or retroperitoneal air on plain abdominal films. DPL unreliable. At laparotomy, central upper abdominal retroperitoneal hematoma, bile staining, or air: mandates visualization and examination of panc/duo Duodenal injury: –80% lacs (G I-III) - primary repair –10-15% RYDJ, pyloric exclusion, Whipple Pancreatic injury –Late complications: time from injury to tx Abscess, pseudocyst, fistula.

13. Blunt Abdominal Trauma DIAPHRAGMATIC RUPTURE 3-5% of all abdominal injuries, L>R May p/w few signs, need high index of suspicion –Injury mechanism: compartment intrusion, deformity of steering wheel, need for extrication, fall from great height –Prominence/immobility of L hemithorax –NGT in chest, bowel sounds in thorax –CXR: (50% with non-dx initial CXR): Obliteration of L diaphragm on CXR Elevation/irregularity of costophrenic angle Pleural effusion Confirm with GI contrast studies, dx laparoscopy Ex-lap and repair

14. Blunt Abdominal Trauma SMALL BOWEL INJURY Mechanism: rapid deceleration with compression, shearing Often at points of fixation: Treitz, ileocecal valve, prior adhesions, mesentery. Chance fracture (transverse fx of lower thoracic/lumbar vertebral body) raises index of suspicion for SB injury Dx: DPL may be (-) for 6-8h after intestinal perforation, Clinical signs absent until 6-12h post-injury. Delayed perforation: due to direct injury, transmural contusion, ischemia from mesenteric vascular injury; usually presents w/in days.

15. Blunt Abdominal Trauma INJURY TO COLON AND RECTUM Mechanism: rapid deceleration with steering wheel compression uncommon Disruptions of colonic wall or avulsion injury of mesentery Present with hemoperitoneum, peritonitis.

16. Penetrating Abdominal Trauma Evaluation Any penetrating wound between nipples and gluteal crease = potential intra- abdominal injury. Stab wounds: stratify based on location GSW: higher potential for serious injury.

17. Penetrating Abdominal Trauma Evaluation of Stab Wounds Local exploration DPL –5cc gross blood on aspiration –>20K RBC/mm3 –>500 WBC/mm3 –>175U amylase/100mL –Bacteria –Bile, Food particles CT –Limited ability to dx hollow organ injury –Useful for posterior SW FAST –Limited, high false negative rate –Useful for pericardial injuries Diagnostic laparoscopy –Useful for assessing peritoneal penetration, diaphragm injury –Shorter LOS than negative laparotomy

18. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest Anterior Abdominal Flank Peristernal Potential Mediastinal Back

19. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest Anterior Abdominal Explore locally, manage expectantly with serial PE Flank Peristernal Potential Mediastinal Back

20. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest Anterior Abdominal Explore locally, manage expectantly with serial PE Flank explore locally triple contrast CT Peristernal Potential Mediastinal Back

21. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest Anterior Abdominal Explore locally, manage expectantly with serial PE Flank explore locally triple contrast CT Peristernal Potential Mediastinal Back admit for obs

22. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest ?Thoracoscopy, Laparoscopy Anterior Abdominal Explore locally, manage expectantly with serial PE Flank explore locally triple contrast CT Peristernal Potential Mediastinal Back admit for obs

23. Penetrating Abdominal Trauma Stab Wounds: Stratification by loci Lower Chest ?Thoracoscopy, Laparoscopy Anterior Abdominal Explore locally, manage expectantly with serial PE Flank explore locally triple contrast CT Peristernal Potential Mediastinal CVP monitor, U/S Observe >6h, repeat CXR Back admit for obs

24. Penetrating Abdominal Trauma Gunshot Wounds Usually require urgent exploration Evaluation for peritoneal penetration v tangential GSW. –CT, diagnostic laparoscopy –Use of DPL controversial due to high false negative rate Ballistics: –Civilian=lower velocity handgun missiles; military = higher velocity rifle missiles –Permanent and temporary cavities: Yaw, Bullet size and type –Shotgun: Short range: high-velocity and more concentrated Distant range: multiple low-velocity projectiles, more diffuse, less severe Antibiotics: cefotetan or cefoxitin in ED

25. Penetrating Abdominal Trauma ROLE OF DIAGNOSTIC LAPAROSCOPY IN EVALUATING GSW AND NEED FOR LAPAROTOMY 66 GSW underwent DL, 2/3 of GSW in upper torso Peritoneal penetration ruled out in 62% 29% had therapeutic ex-lap, 5% had non-therapeutic ex-lap, 4% had negative ex-lap Hospital stay: –4.3 days - negative DL and associated injuries –8.6 days - laparotomy –1.1 days - negative DL and no associated injuries. –Fabian et al, Ann Surg 1993; 217:557

26. Penetrating Abdominal Trauma IMPACT OF DIAGNOSTIC LAPAROSCOPY ON NEGATIVE LAPAROTOMY RATE Retrospective review 817 pts who underwent ex-lap for abdominal GSW over 4yr: negative ex-lap rate = 12.4% –22% morbidity, LOS 5.1days Review of 85 pts with abdominal GSW evaluated with DL –Negative DL in 65%, no missed injuries, no subsequent need for ex-lap; 3% morbidity rate (one pt had urinary retention), LOS 1.4days –Positive DL in 35%, 28 of 30 underwent ex-lap, 86% therapeutic and 14% nontherapeutic (remaining 2 were observed for nonbleeding liver lacs) –Sosa et al. J Trauma 1995;38(2):194

27. Penetrating Abdominal Trauma IMPACT OF DIAGNOSTIC LAPAROSCOPY ON NEGATIVE LAPAROTOMY RATE Prospective study of 121 patients with tangential GSW, HD stable 65% negative DL Of 25% positive DL, 92.8% (39) underwent ex-lap –82% (32) therapeutic, 15.4% (6) nontherapeutic, 2.5% (1) negative No false negative DLs, no delayed laparotomies Sensitivity for peritoneal penetration 100% –Sosa et al. J Trauma 1995;39(3):501