1. What is a solitary pulmonary nodule?

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A solitary pulmonary nodule or “coin lesion” is < 3 cm and is discrete on chest radiograph. It is usually surrounded by lung parenchyma.

2. What causes a solitary pulmonary nodule?

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The most common causes of a pulmonary nodule are either neoplastic (carcinoma) or infectious (granuloma). Pulmonary nodules may also represent lung abscess, pulmonary infarction, arteriovenous malformations, resolving pneumonia, pulmonary sequestration, hamartoma, and others. As a general rule of thumb, likelihood of malignancy is proportionate to the patient’s age. Thus, whereas lung cancer is rare (although it does occur) in 30-year-old individuals, in 50-year-old smokers, the chances of malignancy may be as high as 50-60%.

3. How does a solitary pulmonary nodule present?

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Typically, a solitary nodule is picked up incidentally on routine chest radiograph. In several large series, more than 75% of lesions were surprise findings on routine chest radiograph. Fewer than 25% of patients had symptoms referable to the lung. Solitary nodules are now seen on other sensitive imaging tests such as helical computed tomography (CT).

4. How frequently does a solitary pulmonary nodule represent metastatic disease?

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Fewer than 10% of solitary nodules represent metastatic disease. Accordingly, an extensive workup for a primary site of cancer other than the lung is not indicated.

5. Can a tissue sample be obtained by fluoroscopic or CT-guided needle biopsy?

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Yes, but the results do not change the treatment. If the needle biopsy tissue indicates cancer, the nodule must be removed. If the needle biopsy is negative for cancer, the nodule must still be removed. Positron emission tomography (PET) is 90% sensitive in identifying malignant tumors.

6. Are radiographic findings important?

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Only relatively. The resolution of modern CT scanners allows the best identification of characteristics that suggest cancer:

1. Indistinct or irregular spiculated borders of the nodule.
2. The larger the nodule, the more likely it is to be malignant.
3. Calcification in the nodule generally is associated with benign disease (the opposite of breast cancer). Specifically, whereas central, diffuse, or laminated calcifications are typical of a granuloma, calcifications with more dense and irregular “popcorn” patterns are associated with hamartomas. Unfortunately, eccentric foci of calcium or small flecks of calcium may be found in malignant lesions.
4. Nodules can be studied using a CT scanner by measuring their change in relative radiodensity after injection of contrast. This information improves the accuracy of predicting the presence of malignancy.

KEY POINTS: SOLITARY PULMONARY NODULE

1. A solitary pulmonary nodule or “coin lesion” is < 3 cm and is discrete on chest radiograph.
2. The most common causes of a pulmonary nodule are either neoplastic or infectious.
3. If the lesion proves to be cancer, anatomic lobectomy is the procedure of choice.

7. What social or clinical findings suggest that a nodule is malignant rather than benign?

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Unfortunately, none of the findings is sufficiently sensitive or specific to influence the work-up. Both increasing age and a long smoking history predispose patients to lung cancer. Winston Churchill should have had lung cancer, but he did not. Thus, the fact that the patient is the president of the spelunking club (histoplasmosis), has a sister who raises pigeons (cryptococcosis), grew up in the Ohio River Valley (histoplasmosis), works as sexton for a dog cemetery (blastomycosis), or just took a hiking trip through the San Joaquin Valley (coccidioidomycosis) is interesting associated history but does not affect the work-up of a solitary pulmonary nodule.

8. What is the most valuable bit of historic data?

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The most valuable is an old chest radiograph. If the nodule is new, it is more likely to be malignant, whereas if the nodule has not changed in the past 2 years, it is less likely to be malignant. Unfortunately, even this observation is not absolute.

9. If a patient presents with a treated prior malignancy and a new solitary pulmonary nodule, is it safe to assume that the new nodule represents metastatic disease?

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No. Even in patients with known prior malignancies, < 50% of new pulmonary nodules are metastatic. Thus, the work-up should proceed exactly as for any other patient with a new solitary pulmonary nodule.

10. How should a solitary pulmonary nodule be evaluated?

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A complete travel and occupational history is interesting but does not affect the evaluation. Because of the peripheral location of most nodules, bronchoscopy has a diagnostic yield of < 50%. Even in the best hands, sputum cytology has a low yield. CT scanning is recommended because it can identify other potentially metastatic nodules and delineate the status of mediastinal lymph nodes. As indicated previously, percutaneous needle biopsy has a diagnostic yield of approximately 80% but rarely alters the subsequent management. PET scanning may suggest cancer with accuracy.
The mainstay of management in patients who can tolerate surgery is resection of the nodule, usually by lobectomy if cancer is suspected, for diagnosis by either a minimally invasive thoracoscopy approach or a limited thoracotomy.

11. If the lesion proves to be cancer, what is the appropriate surgical therapy?

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Although several series have suggested that wedge excision of the nodule is sufficient, an anatomic lobectomy remains the procedure of choice. This can often be accomplished by a video-assisted approach. A solitary nodule that turns out to be cancer should be early-stage disease and has a 65% 5-year survival rate if there are no notable metastases. Unfortunately, the recurrence rate even for stage I tumors or a small nodule is 30% over 5 years. Recurrences are split between local and distant.

References
WEB SITE
http://www.acssurgery.com
BIBLIOGRAPHY
1. Dewey TM, Mack MJ: Lung cancer: Surgical approaches and incisions. Chest Surg Clin North Am 10:803-820, 2000.
2. Ginsberg RJ, Rubinstein LV: Randomized trial of lobectomy versus limited resection for T1 N0 non-small cell lung cancer. Lung Cancer Study Group. Ann Thorac Surg 60:615-622, 1995. Medline Similar articles Full article
3. Khouri NF, Meziane MA, Zerhouni EA, et al: The solitary pulmonary nodule: Assessment, diagnosis and management. Chest 91:128-133, 1987. Medline Similar articles
4. Miller DL, Rowland CM, Deschamps C, et al: Surgical treatment of non-small cell lung cancer 1 cm or less in diameter. Ann Thorac Surg 73:1541-1545, 2002.
5. Nesbitt J, Putnam JB Jr, Walsh GL, et al: Survival in early stage non-small cell lung cancer. Ann Thorac Surg 60:466-472, 1995. Medline Similar articles Full article
6. Walsh GL, Pisters KM, Stevens C: Treatment of stage I lung cancer. Chest Surg Clin North Am 10:17-38, 2001.

COLON TRAUMA

1. How do most colon injuries occur?

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Nearly all (> 95%) colon injuries are caused by penetrating trauma from gunshot, stab, iatrogenic, or sexual injury. Blunt colonic trauma is rare and usually results from seat belts during motor vehicle accidents.

2. How are colon injuries diagnosed?

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They are usually diagnosed during laparotomy for penetrating trauma. For patients in whom the need for laparotomy has not been established, chest and upright abdominal radiographs assess free air and detect the location of penetrating objects. Triple-contrast computed tomography (CT) or soluble-contrast radiographs (followed by barium, if necessary) can diagnose retroperitoneal colon injuries. White blood cells or fecal material in diagnostic peritoneal lavage (DPL) is highly suggestive of a bowel injury.

3. How are colon injuries graded?

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* Grade I-contusion hematoma without devascularization; or partial-thickness laceration
* Grade II-laceration < 50% circumference
* Grade III-laceration > 50% circumference
* Grade IV-transection of the colon
* Grade V-transection with segmental tissue loss

4. What are three surgical options for managing a colon injury?

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1. Primary repair: suturing of simple sidewall perforations or resection and primary anastomosis for more complex injuries
2. Colostomy: injured colon is exteriorized as a loop colostomy or the injured area is resected and an end ileostomy or proximal colostomy is formed
3. Exteriorized repair: a repaired perforation or anastomosis is suspended on the abdominal wall. If the suture line does not leak after 10 days, it can be returned to the abdominal cavity under local anesthesia. If the repair breaks down, it is treated like a loop colostomy.

5. What are the advantages and disadvantages of each of these options?

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1. Primary repair is desirable because definitive treatment is carried out at the initial operation and the patient is spared the morbidity of a colostomy and its reversal. The disadvantage is that suture lines are created in suboptimal conditions, so leakage may occur.
2. Proximal colostomy avoids an unprotected suture line in the abdomen but requires a second operation to close the colostomy. Stomal complications, including necrosis, stenosis, obstruction, and prolapse, may occur.
3. Exteriorized repair is similar to colostomy formation in that it avoids formation of an intraperitoneal suture line. Unfortunately, many patients require a colostomy closure, and stomal complications similar to those of colostomies may occur.

6. How are most patients with colon injuries surgically managed?

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Primary repair is safe and effective in essentially all patients with colon trauma. Handsewn and stapled anastomoses have equal complication rates.
KEY POINTS: SURGICAL MANAGEMENT OF COLON INJURIES

1. Primary repair is safe.
2. Handsewn and stapled anastomoses have equal complication rates.
3. A preoperative dose of antibiotic therapy, to be continued for 24 hours, is advantageous.

7. How should the surgical incision and penetrating wound be managed?

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Wounds should be left open (for delayed primary closure) to decrease the incidence of wound infection and fascial dehiscence.

8. What complications are associated with colonic injury and its treatment?

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* Wound infection (≤ 65% if the skin incision is closed primarily; do not be tempted to close a dirty incision)
* Intraabdominal abscess (20%)
* Fascial dehiscence (10%)
* Stomal complications (5%)
* Anastomotic leak (5%)
* Mortality (6%)

14. What is the role of laparoscopy and thoracoscopy after penetrating abdominal trauma?

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Although an intriguing diagnostic modality with additional therapeutic capabilities, laparoscopy thus far appears to have limited application after trauma. With the exception of suspected diaphragmatic injury, an isolated solid organ injury, or evaluation for peritoneal penetration, laparoscopy has yet to demonstrate advantages over the algorithm delineated above. The potential for missed injuries, poor evaluation of the retroperitoneum, and expense are major drawbacks. In patients with wounds to the lower chest with pneumothorax (and, thus, an indication for chest tube placement), thoracoscopy is reasonable to exclude diaphragmatic injury.

References
WEB SITES

1. http://www.east.org/tpg/atbpenetra.pdf
2. http://www.surgery.ucsf.edu/eastbaytrauma/Protocols/ER%20protocol%20pages/abdominal_stab.htm

BIBLIOGRAPHY
1. Chiu WC, Shanmuganathan K, Mirvis SE, Scalea TM: Determining the need for laparotomy in penetrating torso trauma: A prospective study using triple-contrast enhanced abdominopelvic computed tomography. J Trauma 51:860-868, 2001. Medline Similar articles Full article
2. Freeman RK, Al-Dossari G, Hutcheson KA, et al: Indications for using video-assisted thoracoscopic surgery to diagnose diaphragmatic injuries after penetrating chest trauma. Ann Thorac Surg 72:342-347, 2001.
3. Henneman PL, Marx JA, Moore EE, et al: Diagnostic peritoneal lavage: accuracy in predicting necessary laparotomy following blunt and penetrating trauma. J Trauma 30:1345-1355, 1990. Medline Similar articles
4. McAlvanah MJ, Shaftan GW: Selective conservatism in penetrating abdominal wounds: A continuing reappraisal. J Trauma 18:206-212, 1978. Medline Similar articles
5. McAnena OJ, Marx JA, Moore EE: Peritoneal lavage enzyme determinations following blunt and penetrating abdominal trauma. J Trauma 31:1161-1164, 1991.
6. Moore EE, Marx JA: Penetrating abdominal wounds: A rationale for exploratory laparotomy. JAMA 253:2705-2708, 1985.
7. Reber PU, Schmied B, Seiler CA, et al: Missed diaphragmatic injuries and their long-term sequelae. J Trauma 44:183-188, 1998.
8. Simon RJ, Rabin J, Kuhls D: Impact of increased use of laparoscopy on negative laparotomy rates after penetrating trauma. J Trauma 53:297-302, 2002. Similar articles Full article

1. How often is the liver injured in trauma?

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The liver is both big and central, so it is an easy target.

2. Do the liver and spleen respond similarly to injury?

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No. The liver has a unique ability to establish spontaneous hemostasis even with extensive injuries. For this reason, the majority of liver injuries in hemodynamically stable patients can be managed nonoperatively. In contrast, many splenic fractures continue to bleed; therefore, a greater percentage require operative intervention.

3. What are the determinants of mortality after acute liver injury?

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The mechanism of injury and the number of associated abdominal organs injured determine mortality. The mortality for stab wounds to the liver is 2%; for gunshot wounds, 8%; and for blunt injuries, 15%. The mortality rate for isolated grade III hepatic injuries is 2%; for grade IV, 20%; and for grade V, 65%. Retrohepatic vena cava injuries carry mortality rates of 80% for penetrating trauma and 95% for blunt trauma.

4. What history and physical signs suggest acute liver injury?

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Any patient sustaining blunt abdominal trauma with hypotension must be assumed to have a liver injury until proven otherwise. Specific signs that increase the likelihood of hepatic injury are contusion over the right lower chest, fracture of the right lower ribs (especially posterior fractures of ribs 9-12), and penetrating injuries to the right lower chest (below the fourth intercostal space, flank, and upper abdomen). Physical signs of hemoperitoneum may be absent in as many as one third of patients with significant hepatic injury.

5. What diagnostic tests are helpful in confirming acute liver injury?

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A focused abdominal sonography for trauma (FAST) examination can detect or rule out hemoperitoneum and pericardial tamponade. Diagnostic peritoneal lavage (DPL) is sensitive for hemoperitoneum (99%). Ultrasound is highly sensitive in identifying > 200 mL of intraperitoneal fluid. It is noninvasive and may be repeated at frequent intervals, but it is relatively poor for staging liver injuries. Abdominal computed tomography (CT) scan currently is used only in hemodynamically stable patients who are candidates for nonoperative management. The major shortcoming of CT is the relatively poor correlation between hepatic CT staging and subsequent risk of hemorrhage.

6. What is the role of hepatic angiography and radionuclide biliary excretion scans in the diagnosis of liver injury?

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Selective hepatic artery embolization is effective therapy for hepatic arterial bleeding, both for avoidance of surgery and for recurrent postoperative bleeding.

1. What are the causes of bladder injury?

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Iatrogenic manipulation and penetrating or blunt trauma. Because of the rich detrusor blood supply, bladder injury is usually accompanied by hematuria. Other signs may include suprapubic pain, inability to void, or incomplete recovery of catheter irrigation.

2. What types of bladder injury may occur with blunt trauma?

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Laceration or perforation may be either intra- or extraperitoneal. Hematuria with a normal cystogram defines bladder contusion in the absence of upper tract injury. Extraperitoneal injuries constitute the majority of bladder trauma and tend to concentrate at the bladder base or parasymphyseal area. These can be managed conservatively with urinary catheter drainage for at least 10 days. Intraperitoneal (IP) ruptures typically occur when the bladder is distended at the time of trauma, causing a blowout of the dome of a bladder. IP vesical rupture should be surgically repaired using a two-layer closure with absorbable sutures and placement of suprapubic and urethral catheters.
KEY POINTS: MANAGEMENT OF BLADDER INJURY DUE TO BLUNT TRAUMA

1. Diagnose with CT cystography and retrograde cystourethrography.
2. Extraperitoneal injuries are more common and may be managed conservatively with a Foley catheter for 10 days.
3. Intraperitoneal injuries are more likely if the bladder is distended at the time of injury; they require surgical repair with suprapubic and Foley drainage postoperatively.

3. What is the likelihood of a bladder injury in patients with a fractured pelvis?

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Extraperitoneal bladder injury occurs in 10% of all pelvic fractures. Conversely, approximately 85% of blunt bladder injury is associated with pelvic fracture. Bladder injuries occur more often with parasymphyseal pubic arch fractures and more often with bilateral than unilateral fractures. Isolated ramus fractures produce bladder laceration in 10% of cases.

4. How is bladder injury evaluated?

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Both computed tomography (CT) cystography and retrograde cystourethrography provide great diagnostic accuracy for bladder rupture. The bladder should be filled under gravity with a total of 300-400 mL of a 50% dilution of standard radiocontrast agent using the Foley catheter. Films should include anteroposterior, lateral, and oblique views. Finally, a postvoid film should be obtained. When renal or distal ureteral injury is suspected, upper tract imaging (intravenous pyelogram [IVP] or CT scan) should precede the cystogram.

5. What are the retrograde cystourethrographic patterns of bladder injury?

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Extraperitoneal injury allows contrast agent to escape adjacent to the symphysis, but it is confined to the bladder base by the intact peritoneum. Intraperitoneal extravasation produces a “sunburst” appearance from the bladder dome, which may collect in the paracolic gutters, outline loops of bowel, or pool under the liver or spleen. It is pivotal to obtain postvoid films.

6. How is bladder rupture managed?

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Extraperitoneal lacerations can be managed with an indwelling catheter for 7-10 days, at which time cystogram usually confirms resolution of extravasation. Intraperitoneal lacerations require operative repair. Bladder contusion requires catheter drainage until gross bleeding has subsided.

7. When should urethral injury be investigated?

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The mechanism of injury (e.g., crushing or deceleration/impact, straddle injuries) and associated trauma (e.g., pelvic fracture), blood at the meatus, penile or scrotal swelling and ecchymosis, upward prostatic displacement on digital rectal examination, and inability to void or to pass a urethral catheter (do not try this) should be investigated.

8. When a patient presents with a pelvic fracture, is concomitant urethral injury a major concern?

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Yes. Urethral trauma occurs in 10% of pelvic fractures; it is more common with anterior disruption of the pelvic ring, including 20% of unilateral and 50% of bilateral parasymphyseal fractures. Posterior (prostatomembranous) avulsion is associated with potentially disabling sequelae and requirements for complex and challenging operative corrections. In contrast, more distal urethral injuries avoid impotence and incontinence issues and are more surgically accessible.

9. How is urethral injury best assessed?

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Retrograde urethrography must always be performed before inserting a Foley catheter. Incomplete urethral transection produces local contrast dye extravasation and bladder opacification. Total avulsion produces extensive local extravasation, and no contrast dye gets into the bladder. Incomplete transection is more common with anterior (50%) than posterior (10%) urethral injuries.

10. How is urethral injury managed?

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For incomplete transection regardless of site, either catheter stenting across the defect or diversion by suprapubic cystostomy permits resolution. With complete urethral transection, the bladder should be decompressed initially via suprapubic cystostomy. Early restoration of continuity by placement of a bridging urethral catheter should be performed endoscopically. A bridging catheter reduces complex scarring and avoids subsequent surgery in many patients.

11. What are the complications of urethral injury?

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Strictures, incontinence, and impotence (associated with traumatic prostatic displacement). Iatrogenic complications are associated with retropubic dissection.

12. What is the differential diagnosis in blunt scrotal trauma?

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Testicular rupture, hematocele, scrotal hematoma, intratesticular hematoma, and testicular torsion. Ultrasonography helps sort this out.

13. What is the sonographic sign of testicular rupture?

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The sign is loss of the normal homogenous echo texture of the testicle, with areas of irregular hyper- or hypoechogenicity.

14. How are patients with acute testicular rupture managed?

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Management includes surgical exploration and debridement of extruded, nonviable tubules and evacuation of the hematoma. After proper hemostasis is achieved, the tunica albuginea should be closed with running absorbable suture.

15. What is the most common cause of penile fractures?

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Penile fracture is a rupture of the corpus cavernosum, most commonly associated with sexual intercourse, masturbation, or an abnormally forced bending of the erect penis. Characteristically the patient hears a popping sound, followed by pain and detumescence.

16. What are the physical examinations findings with a penile fracture?

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Injury to the tunica albuginea causes formation of hematoma and deviation of the shaft to the opposite side of injury. If Buck’s fascia is intact, the hematoma will be confined to the penis; disruption of Buck’s fascia allows spread of the hematoma under Colles’ and Scarpa’s fascia onto the perineum and abdominal wall.

17. How are penile fractures managed?

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Surgically. A retrograde urethrogram should be performed when urethral injury is suspected. Closure of the defect (or defects) along the tunica albuginea and evacuation of hematoma are performed after degloving the penis.

18. In penile amputation injuries, how should the amputated portion of the penis be preserved for transport?

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The amputated portion of the penis should be wrapped in saline-soaked gauze, placed in a plastic bag with ice slush surrounding the bag.

19. How is major scrotal skin loss managed?

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If primary repair is not possible, meshed split-thickness skin grafts may be used to cover the testis. When delayed repair is necessary, thigh pouches should be created until permanent reconstruction is feasible.

20. A 50-year-old woman complains of urine leakage from her vagina after a hysterectomy. What is the most likely diagnosis?

Show answer
Unrecognized bladder injury during hysterectomy with subsequent urine extravasation into the surgical field and drainage via the vaginal cuff suture line leads to formation of vesicovaginal fistula.

21. What is the best time to repair a vesicovaginal fistula secondary to an uncomplicated hysterectomy?

Show answer
Although 3-6 months after injury has been recommeded in the past, early repair can be successful if there is minimal inflammation and there are no complicating factors.

References
WEB SITES

1. http://www.east.org/tpg/GUmgmt.pdf
2. http://www.acssurgery.com/abstracts/acs/acs0510.htm

BIBLIOGRAPHY
1. Armstrong PA, Litscher LJ, Key DW, McCarthy MC: Management strategies for genitourinary trauma. Hosp Phys 34:19-25, 1998.
2. Jacob TD, Gruen GS, Udekwu AO, Peitzman AB: Pelvic fracture. Surg Rounds (Aug):583, 1993.
3. Jordan GH: Lower Genitourinary Tract Trauma and Male External Genital Trauma (Nonpenetrating Injuries, Penetrating Injuries, and Avulsion Injuries). In American Urological Association Update Series, Vol. XIX, Lesson 11, part 2. Baltimore, American Urological Association, 2000.
4. Kim FJ: Urologic trauma. In Feliciano DV, Moore EE, Mattox KL (eds): Trauma Companion Handbook, 4th ed. New York, McGraw-Hill, 2002.
5. McAninch JW: Traumatic and Reconstructive Urology. Philadelphia, W.B. Saunders, 1996.
6. Peterson NE: Current management of urethral injuries. In Rous S (ed): 1998 Urology Annual. New York, Appleton-Century-Crofts, 1988, pp 143-179.
7. Peterson NE: Traumatic posterior urethral avulsion. Mongr Urol 7:61, 1986.
8. Spirnak JP: Pelvic fracture and injury to the lower urinary tract. Surg Clin North Am 68:1057, 1988. Medline Similar articles

1. What is the physiologic role of the spleen?

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In fetal development, the spleen serves as a major site for hematopoiesis. In early childhood the spleen produces immunoglobulin M (IgM) and tuftsin. The spleen also functions as a filter, allowing resident macrophages to remove abnormal red blood cells (RBCs), cellular debris, and encapsulated and poorly opsonized bacteria.

2. What injury patterns are associated with splenic trauma?

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Direct blunt force, deceleration, and compression to the left torso. Think spleen after a motor vehicle accident or fall: lower rib fractures, left side-only rib fractures, and high-energy transfer (big hits) increase the probability of splenic injury.

3. What are the signs and symptoms of splenic injury?

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The main sign is pain in the left upper quadrant. This is produced by stretching the splenic capsule. Peritoneal irritation (rebound tenderness) is caused by extravasated blood (blood is very irritating). Vital signs vary depending on associated blood loss and are not specific for injuries to the spleen. Unfortunately, a large number of patients with a significant splenic injury exhibit no signs or symptoms at all.

4. What studies can help in diagnosing splenic trauma?

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Ultrasound (US) can be performed in the emergency department and can rapidly identify as little as 200 mL fluid/blood. When US is not available, diagnostic peritoneal lavage (DPL) is an accurate and sensitive measure of intraabdominal bleeding.
Hemodynamically stable patients permit more thorough evaluations. Although US is extremely sensitive for detecting intraabdominal bleeding, computed tomography (CT) not only can detect and quantify intraabdominal blood but also can characterize specific intraabdominal injuries.

5. How are splenic injuries classified, and why is that important?

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Management is governed by the hemodynamic status of the patient, but therapy is also influenced by the CT grade of splenic injury. Nonoperative management is most successful in grades I-III, whereas operative intervention is often required for grade IV injuries. Grade V injuries demand prompt operative intervention. (See Table 26-1.)

6. Do splenic injuries require laparotomy?

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No. Nonoperative management is successful in approximately 95% of patients with grades I-III. Hemodynamically stable patients with evidence of ongoing bleeding (requiring transfusion) may be treated by selective arterial embolization if a bleeding site is identified on angiography.

7. What are contraindications to nonoperative management of splenic injuries?

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* Hemodynamic instability
* Persistent coagulopathy
* Additional intraabdominal injury requiring operative intervention
. GRADES OF SPLENIC INJURY

8. What is the failure rate of nonoperative management of splenic injury?

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Any patient with signs of hemodynamic instability, persistent bleeding, worsening pain or tenderness, or progressive injury by CT scanning has failed nonoperative management. Approximately 60% of all splenic injuries can be managed nonoperatively with a failure rate of 12%. Factors that predict nonoperative failure include multiple injuries, grade III-V spleen injuries, age > 55 years, and blood traunsfusion.
KEY POINTS: EXPECTANT MANAGEMENT OF SPLENIC INJURIES

1. Nonoperative management is successful in 95% of grades I-III injuries.
2. 60% of all splenic injuries are managed nonoperatively, with a 12% failure/conversion rate.
3. Factors that predict failure/conversion to operative treatment include injury > grade III, age > 55 years, and blood transfusion requirements.
4. Patients with evidence of ongoing bleeding (e.g., contrast “blush” on CT or ongoing transfusion requirements) may be managed with selective arterial embolization.

9. What is delayed rupture of the spleen?

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This is a rare complication that occurs in < 1% of patients with a splenic injury. Delayed splenic rupture should be distinguished from a delay in diagnosis of splenic injury and rupture of a known splenic injury. True delayed splenic rupture occurs > 48 hours in a patient with a history of abdominal trauma and no overt clinical evidence of intraabdominal injury on initial presentation.

10. What are the general principles of operative management of the injured spleen?

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The first priority is to control bleeding. This can usually be accomplished by packing and manual compression of the spleen. If successful, the abdomen is then thoroughly explored for other injuries. Complete mobilization of the spleen by division of the splenocolic, splenorenal, phrenosplenic, and gastrosplenic ligaments is required for complete assessment of the spleen. The short gastric vessels can be ligated with division of the gastrosplenic ligament. Repair of the spleen can be accomplished by application of hemostatic agents, direct pledgeted suture repair of the splenic parenchyma, partial splenectomy, and construction of a “splenic wrap” using absorbable mesh. If splenectomy is required, the splenic artery and vein should be ligated individually prior to removing the spleen.

11. What early complications arise after splenectomy?

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Bleeding, acute gastric dilatation, gastric perforation, pancreatitis (the splenic artery courses along the top of the pancreas), and subphrenic abscess.

12. What is splenic autotransplantation?

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Autotransplantation is accomplished by implanting splenic tissue parenchymal slices into pouches created in the gastrocolic omentum.

13. Does splenic autotransplantation preserve splenic function?

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Autotransplantion after splenectomy is controversial. At least 30% of the original splenic mass is needed to provide normal function. After autotransplantation, IgG and IgM levels are increased in response to pneumococcal vaccine compared with patients after splenectomy alone.

14. Does postsplenectomy leukocytosis predict infection?

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Elevations in white blood cell (WBC) count and platelet count (PC) after splenectomy are a common physiologic event. After the fourth postoperative day, however, a WBC > 15 x 103 and a PC/WBC < 20 are highly associated with sepsis and should not be confused with the physiologic response to splenectomy.

15. Should a follow-up CT scan be performed after nonoperative management of splenic injuries before patient discharge?

Show answer
No. Most patients who fail nonoperative management do so within 5 days and will exhibit hemodynamic evidence of ongoing hemorrhage. However, follow-up CT should be performed for grade III and IV injuries at 4-6 weeks before getting back to vigorous physical activity.

16. What is OPSS, and how is it prevented?

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Overwhelming post splenectomy sepsis (OPSS) is a devastating bacteremia (typically encapsulated bacteria) that occurs in 2% of patients after splenectomy. The risk of OPSS is greatest when splenectomy is performed during infancy. The most common organisms are pneumococcus (50%), meningococcus, Escherichia coli, Haemophilus influenzae, staphylococcus, and streptococcus. Although rare, OPSS carries a mortality rate of 75% and has spurred interest in splenic preservation. OPSS is primarily prevented by postoperative vaccination. Pneumococcal, meningococcal, and Haemophilus flu vaccines should be given 2 weeks after splenectomy and are recommended every 5 years. Sepsis can occur despite vaccination; consequently, long-term prophylaxis with oral penicillin is recommended for children.

References
WEB SITES

1. http://www.east.org/tpg/bluntabd.pdf
2. http://www.acssurgery.com/abstracts/acs/acs0506.htm

BIBLIOGRAPHY
1. Cocanour CS, Moore FA, Ware DN, et al: Delayed complications of nonoperative management of blunt adult splenic trauma. Arch Surg 133:619-624, 1998. Medline Similar articles Full article
2. Leemans R, Manson W, Snijder JA, et al: Immune response capacity after human splenic autotransplantation: Restoration of response to individual pneumococcal vaccine subtypes. Ann Surg 229:279-285, 1999. Medline Similar articles Full article
3. Moore EE, Cogbill TH, Jurkovich GJ, et al: Organ injury scaling: Spleen and liver (1994 revision). J Trauma 38:323-324, 1995.
4. Shatz DV: Vaccination practices among North American trauma surgeons in splenectomy for trauma. J Trauma 53:950-956, 2002. Medline Similar articles Full article
5. Toutouzas KG, Velmahos GC, Kaminski A, et al: Leukocytosis after posttraumatic splenectomy: A physiologic event or sign of sepsis? Arch Surg 137:924-928, 2002. Full article
6. Uecker J, Pickett C, Dunn E: The role of follow-up radiographic studies in nonoperative management of spleen trauma. Am Surg 67:22-25, 2001. Medline Similar articles

1. What elements of the history are important in evaluating a patient with suspected blunt abdominal trauma (BAT)?

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First, the mechanism of injury (e.g., motor vehicle collision, automobile-pedestrian accident, fall) is important. In motor vehicle accidents, note the position of the victim in the car, velocity of impact (high, moderate, low), type of accident (front, lateral, or rear impact; side swipe; rollover), and type of restraint used (shoulder restraint, air-bag, lap belt). Information about damage to the vehicle, such as a broken windshield or bent steering wheel, may raise suspicion of cervical and chest injuries. In a fall, it is important to note the distance fallen and the site of anatomic impact. Vertical landing on the feet or in a sitting position causes a different pattern of injury than lateral landing on the side. Serial vital signs and mental status are always important.

2. Is physical examination accurate in the diagnosis of intraabdominal injury?

Show answer
No. The examination results may be normal in up to 50% of patients with acute intraabdominal bleeding. Signs of intraabdominal injury include abrasions and contusions over the lower chest and abdomen; subcutaneous emphysema or palpable rib fracture; clinically evident pelvic fracture; abdominal pain, tenderness, guarding, or rigidity; blood in the urine or urethral meatus; high-riding prostate or blood on rectal examination; and microscopic hematuria.
3. Which organs are most frequently injured in BAT?

4. What diagnostic studies are helpful in BAT?

Show answer

1. Ultrasound: reliably identifies peritoneal fluid (blood) and pericardial fluid but may miss up to 25% of isolated solid organ injuries.
2. Computed tomography (CT) scan: identifies the presence and severity of solid organ injury (liver and spleen), detects intraabdominal air and fluid (blood, mucus, urine), and aids in evaluation of pelvic fractures. CT scanning can also identify bowel, pancreatic, renal, and bladder injuries.
3. Diagnostic peritoneal lavage (DPL): grossly positive DPL (> 10 mL blood returned by aspiration of the catheter) indicates significant hemoperitoneum. Positive by cell count after infusion of 1 L of crystalloid fluid (> 100,000 red blood cells/mm3, presence of bile or fibers) indicates intraabdominal bleeding, injury to hollow viscus, or hepatobiliary system injury. Lavage fluid exiting through a chest tube or urinary catheter indicates diaphragmatic or bladder injury.

5. How has the availability of ultrasound (US) changed the initial evaluation of BAT?

Show answer
The focused abdominal sonography for trauma (FAST) examination has largely supplanted the DPL. The FAST examination can be performed in a hemodynamically unstable patient during the early secondary survey with immediate transfer to the operating room when hemoperitoneum is identified. CT scan is safe in the hemodynamically stable patient. DPL is still useful when US is equivocal or not available and for evaluation of hollow organ injury.

6. How is hollow organ injury diagnosed?

Show answer
CT findings include peritoneal fluid without solid organ injury, extravasation of oral contrast into the peritoneal cavity, and free intraabdominal air. Suggestive signs include mesenteric stranding and hematoma. Peritoneal lavage results suggestive of hollow organ injury include elevated amylase, alkaline phosphatase, or biliribun levels and the presence of particulate matter.
KEY POINTS: USEFUL DIAGNOSTIC MODALITIES IN BAT

1. Primary and secondary surveys are crucial, but further diagnostic testing is required in most patients.
2. FAST: reliably identifies intraabdominal and intrapericardial fluid but is poor at hollow viscus evaluation.
3. DPL: effective for evaluation of hemoperitoneum and a useful adjunct along with FAST exam.
4. CT: excellent modality with 99.97% negative predictive value for BAT.

7. What are the indications for urgent operation in a patient with BAT?

Show answer
Any hemodynamically unstable patient who exhibits significant hemoperitoneum (by US or DPL) requires emergency laparotomy. Other indications for urgent laparotomy include free intraabdominal air and evidence of hollow viscus injury.

8. How does time in the emergency department (ED) impact the mortality of patients requiring emergent operation for BAT?

Show answer
The probability of death from trauma is related to both the extent of hypotension and the interval from the time of injury to definitive surgery. An estimated increase in mortality of 1% is incurred for every 3 minutes spent in the ED up to 90 minutes.

9. What is the role of angiographic embolization?

Show answer
Angiographic embolization may be effective for hemorrhage control in hemodynamically stable patients. Favorable embolization sites include liver, spleen, and kidney injuries; lumbar arteries with retroperitoneal hemorrhage; and pelvic blood vessels associated with pelvic fracture.

10. What is the “bloody viscus cycle”?

Show answer
The bloody viscus cycle is a syndrome of hypothermia, acidosis, and coagulopathy that occurs with profound hemorrhagic shock and massive transfusion. It represents a circular cascade of events in which severe hemorrhagic shock accompanied by metabolic failure provokes a coagulopathy that exacerbates further bleeding.

11. What is a staged or abbreviated laparotomy (damage control surgery)?

Show answer
Staged laparotomy is terminated before all definitive procedures are completed with the intent to return to the operating room to complete the operation at a later (and safer) time. The purpose of this approach is to delay additional surgical stress until the patient is in a more favorable physiologic state. The objectives of the initial operation become to (1) arrest bleeding and correct coagulopathy; (2) limit peritoneal contamination and the secondary inflammatory response (to control gastrointestinal spillage); and (3) enclose the abdominal contents to protect viscera and limit heat, fluid, and protein loss from an open abdomen.

12. When is staged laparotomy used in trauma patients?

Show answer

* Inability to achieve hemostasis because of recalcitrant coagulopathy (pack the bleeding)
* Inaccessible major venous injury (retrohepatic caval injury)
* Demand for control of a life-threatening extraabdominal (e.g., head or thoracic) injury
* Inability to close the abdominal incision because of extensive visceral edema
* Need to reassess the abdominal contents because of questionable viability at the time of the initial operation

References
WEB SITE
http://www.east.org/tpg/bluntabd.pdf

BIBLIOGRAPHY
1. Branney SW, Moore EE, Cantrill SV, et al: Ultrasound based key clinical pathway reduces the use of hosptial resources for the evaluation of blunt abdominal trauma. J Trauma 42:1086-1090, 1997. Medline Similar articles Full article
2. Burch JM, Denton JR, Noble RD: Physiologic rationale for abbreviated laparotomy. Surg Clin North Am 77:779-782, 1997. Medline Similar articles
3. Clarke JR, Trooskin SZ, Doshi PJ, et al: Time to laparotomy for intra-abdominal bleeding from trauma does affect survival for delays up to 90 minutes. J Trauma 52:420-425, 2002. Similar articles Full article
4. Davis KA, Fabian TC, Croce MA, et al: Improved success in management of blunt splenic injuries: Embolization of splenic artery pseudoaneurysms. J Trauma 44:1008-1013, 1998.
5. Livingston DH, Lavery RF, Passannante MR, et al: Free fluid on abdominal computed tomography without solid organ injury after blunt abdominal injury does not mandate celiotomy. Am J Surg 182:6-9, 2001. Medline Similar articles Full article
6. Miller MT, Pasquale MD, Bromberg WJ, et al: Not so fast. J Trauma 54:52-59, 2003. Medline Similar articles Full article

1. What is the prevalence of thyroid nodules and cancer?

Show answer
Thyroid nodules increase throughout life. Nodules are four times more common in females than in males, and 50% of 50-year-old women have a palpable nodule. After exposure to radiation, nodules develop at approximately 2% annually, reaching a peak at 25 years. Nodules are 10 times more frequent in glands examined by ultrasound, at surgery, or at autopsy. Fewer than 50% of thyroid nodules that appear solitary on physical examination are truly solitary.
Each year in the United States, there are approximately 15,000 new cases and 1000 deaths due to thyroid cancer. Up to 35% of thyroid glands examined at autopsy contain occult papillary cancer (< 1.0 cm).

2. What is the importance of the distinction between solitary and multiple thyroid nodules?

Show answer
Traditionally, multiple thyroid nodules were considered benign and solitary thyroid nodules malignant. However, multiple series suggest that a dominant nodule in a multinodular gland carries the same risk of cancer as a solitary nodule (5%).

3. What is the differential diagnosis of thyroid nodules?

Show answer

* Adenoma
o Macrofollicular (colloid)
o Microfollicular
o Embryonal
o Hurthle cell
* Carcinoma
o Papillary
o Follicular
o Medullary
o Anaplastic
o Lymphoma
o Metastatic
* Cyst
* Nodular goiter with a dominant nodule
* Other
o Inflammatory diseases (e.g., Hashimoto’s thyroiditis)
o Developmental abnormalities

4. What features of the history and physical examination indicate a higher risk of cancer?

Show answer
Nodules occurring at the extremes of age are more likely to be cancerous, particularly in males. Rapid growth and local invasion raise the possibility of malignancy, but associated symptoms (e.g., hoarseness, dysphagia) are uncommon. A history of radiation exposure increases the frequency of both benign and malignant nodules. A family history of medullary or papillary thyroid cancer or Gardner’s syndrome (i.e., familial polyposis) increases the risk of cancer.
Cancer is more often found in patients with firm, solitary nodules. Fixation to adjacent structures, vocal cord paralysis, and enlarged lymph nodes also are associated with an increased risk of malignancy.

5. What is the proper laboratory evaluation of a patient with a thyroid nodule?

Show answer
The only biochemical test that is routinely needed is a serum thyroid-stimulating hormone (TSH) concentration to identify patients with unsuspected hyperthyroidism. In patients with suspected medullary thyroid carcinoma (MTC), serum calcitonin should be measured. In patients with known medullary carcinoma, serum calcium levels and 24-hour urine collection for assessment of catecholamines and their metabolic products should be done to exclude multiple endocrine neoplasia (MEN II) before thyroidectomy. Patients with MTC should have lymphocyte-derived DNA analysis for ret proto-oncogene mutations.

6. Which single test best predicts the need for surgical intervention?

Show answer
The single best test to predict the need for surgery is fine-needle aspiration (FNA). If an adequate specimen is obtained, the three possible results are benign (70%), suspicious (15%), and malignant (5%). FNA is most reliable for the diagnosis of papillary carcinoma and in patients with medullary and anaplastic cancer. It is least reliable in distinguishing benign from malignant follicular and Hurthle cell neoplasms. The overall accuracy exceeds 95% in experienced hands. When FNA reveals cancer, it is 97% correct (3% false-positive rate); when it indicates a benign nodule, cancer is present in 4% of cases (4% false-negative rate). When the FNA is suspicious, 30% of nodules are malignant.

7. What other tests may be useful in the evaluation of a thyroid nodule?

Show answer
Thyroid radionuclide studies with isotopes of either iodine (most common) or technetium often are performed but cannot reliably differentiate malignant from benign nodules. Scans may be useful in patients with indeterminate FNA results and TSH < 1.5 μIU/mL because hyperfunctioning nodules are almost always benign.
Ultrasound categorizes nodules as cystic, solid, or mixed and is the best measure of the size of a nodule. Ultrasound can be used to determine the presence of other nodules in a patient with a solitary nodule on physical examination. It is particularly useful to follow the size of a nodule. Similar to radionuclide scans, ultrasound cannot distinguish malignant from benign nodules; thus, it is not routinely used in the evaluation of a nodule.

8. Should a solitary thyroid nodule be suppressed with thyroxine for 3-6 months to determine whether it is benign or malignant?

Show answer
Most nodules change very little over the short term. In one series, 13% of nodules decreased in size, 22% disappeared, 46% did not change, and 19% enlarged. Studies of thyroxine therapy suggest that drug treatment is not superior to placebo in patients with solitary nodules. Most nodules do not change in size, 30% decrease in size, and a few increase in size. Thus, the response to thyroxine is not a reliable indicator of malignancy.

9. What are the types and distribution of thyroid cancer?

Show answer

10. What are the axioms of thyroid surgery?

Show answer

* A meticulously dry operative field must be maintained.
* Tissue in the region of the recurrent laryngeal nerve should not be cut or clamped until the nerve is definitively identified.
* Every parathyroid gland should be treated as if it were the last functioning gland.
* If malignancy is suspected, the entire operation should be done as if the lesion were cancer.

KEY POINTS: THYROID NODULES

1. Thyroid nodules are more common in females than in males.
2. The only biochemical test that is routinely needed is a serum thyroid-stimulating hormone concentration to identify patients with unsuspected hyperthyroidism.
3. The single best test to predict the need for surgery is fine-needle aspiration.
4. Thyroid carcinoma should be treated by near-total or total thyroidectomy except in young patients with small, well-differentiated tumors (≤ 1 cm) and no evidence of lymph node or extrathyroidal disease. In such cases lobectomy and isthmusectomy are adequate therapy.

11. What is the minimal extent of thyroidectomy for a solitary thyroid nodule?

Show answer
The goal of surgery is to remove all foci of neoplastic tissue and any palpable cervical adenopathy. With the exception of small lesions in the thyroid isthmus, the minimal procedure for suspected malignancy should be lobectomy, including the isthmus (as a diagnostic biopsy). Enucleation is to be avoided. Frozen section is accurate for papillary, medullary, and anaplastic carcinoma. Frozen section is no more accurate than FNA for follicular and Hurthle cell carcinoma. Functioning “toxic” nodules may be resected by a partial lobectomy because they are usually benign. If the lesion is large, a lobectomy is preferred.

12. What is the most common form of thyroiditis in nodules?

Show answer
Hashimoto’s thyroiditis, subacute thyroiditis, and Reidel struma (rare). These conditions usually do not require surgery. Thyroidectomy is indicated for compressive symptoms or when cancer cannot be excluded.

13. What is the surgical therapy for thyroid carcinoma?

Show answer
Thyroid carcinoma should be treated by near-total or total thyroidectomy except in young patients with small, well-differentiated tumors (≤ 1 cm) and no evidence of lymph node or extrathyroidal disease. In such cases, lobectomy with resection of the isthmus is adequate therapy. Near-total thyroidectomy eliminates multifocal cancer in the thyroid, allows postoperative radioiodine for the diagnosis and therapy of metastatic disease, decreases the risk of local-regional recurrence, and improves the accuracy of serum thyroglobulin as a marker for persistent or recurrent disease. Enlarged cervical lymph nodes should be removed and examined by frozen section. If metastatic cancer is identified, a neck dissection is performed. “Berry picking” results in an increased rate of regional recurrence and should be avoided in favor of anatomic dissections.
Because medullary thyroid cancer is not responsive to radioiodine or levothyroxine, a total thyroidectomy should be performed. A central neck dissection is mandatory to evaluate metastatic disease. If the central nodes are positive for cancer on frozen section, an ipsilateral modified neck dissection is performed. The contralateral neck may be observed.
Surgery for anaplastic carcinoma is palliative and usually is limited to debulking and tracheostomy for relief of compressive symptoms.

14. Describe the arterial supply and venous drainage of the thyroid.

Show answer
The blood supply to the thyroid gland comes from the superior and inferior thyroid arteries. Occasionally, a midline thyroid imma artery arises from the aortic arch. The superior thyroid artery is the first branch of the external carotid artery. The inferior thyroid artery arises from the thyrocervical trunk.
The three major veins are the superior, middle, and inferior thyroid veins. The superior and middle thyroid veins drain into the internal jugular vein, and the inferior vein drains into the innominate vein.

15. Describe the anatomy of the recurrent laryngeal nerves.

Show answer
The right recurrent laryngeal nerve (RLN) arises from the vagus and loops around the right subclavian artery. The left vagus nerve gives off the left RLN and loops around the aorta. The RLNs run obliquely through the neck, usually in the tracheoesophageal groove. Low in the neck, the nerves are more lateral and course medially as they ascend. The right nerve runs more obliquely than the left. Occasionally, the RLN may branch before entering the larynx, usually on the left side. The motor fibers are usually in the most medial branch. In 1% of cases, the right RLN is not recurrent and enters the neck from a lateral and superior direction.

16. What defect results from injury to the RLN?

Show answer
Injury to a single RLN results in a paralyzed vocal cord, which causes a weak, hoarse voice. Patients also have abnormal swallowing and problems with aspiration. Injury to both nerves causes paralysis of both cords and obstruction of airflow. This situation necessitates a tracheostomy. RLN injury occurs in 1% of thyroidectomies.

17. Describe the anatomy of the superior laryngeal nerve and the defect that occurs with its injury.

Show answer
The superior laryngeal nerve gives off the external laryngeal nerve, which runs medial to the superior pole vessels to enter the cricothyroid muscle. This motor nerve (i.e., Amelita Galli-Curci nerve) increases tension of the vocal cords, allowing for high notes. The internal laryngeal nerve provides the sensory innervation to the posterior pharynx. It lies superior to the thyroid cartilage. Injury to the nerve leads to a weak, low voice that lacks resonance. Patients may also have problems with aspiration.

18. What is the other major complication of thyroidectomy?

Show answer
Permanent hypoparathyroidism occurs in 1% of patients who have had thyroidectomies.

19. What is the postoperative therapy for well-differentiated thyroid carcinoma?

Show answer
Patients with risk factors should be treated with postoperative radioiodine (I-131). Risk factors include older age (> 45 years old), male gender, tumor size, direct local invasion, nodal spread, and distant disease. All patients with well-differentiated thyroid cancer should be treated with levothyroxine (Synthroid) to suppress serum levels of TSH (0.2-0.5 μU/mL). This three-component therapy (i.e., surgery, I-131, levothyroxine) results in the lowest recurrence rate.

20. How should a patient be followed after therapy for well-differentiated thyroid carcinoma?

Show answer
In young, low-risk patients, physical examination of the neck is done every 6 months for 2 years and then yearly thereafter. In high-risk patients, close follow-up includes repeat neck examination in addition to assessment of serum thyroglobulin (Tg) levels, diagnostic radioiodine scans, and cervical ultrasound. Assessment of the serum Tg and scanning depends on the state of the serum TSH. In order to fully evaluate for recurrent disease, the patient should be taken off thyroxine or given recombinent TSH (Thyrogen).
Patients with recurrent cervical disease by palpation or ultrasound should have repeat surgery if the procedure can be performed with low morbidity. After removal of gross disease, patients should be treated with radioiodine. Distant disease should be treated with radioiodine if the metastases take up iodine.

References
WEB SITE
http://www.acssurgery.com
BIBLIOGRAPHY
1. Cady B: Presidential address: Beyond risk groups-a new look at differentiated thyroid cancer. Surgery 124:947-957, 1998. Medline Similar articles
2. Duren M, Siperstein AE, Shen W, et al: Value of stimulated serum thyroglobulin levels for detecting persistent or recurrent differentiated thyroid cancer in high- and low-risk patients. Surgery 126:13-19, 1999. Medline Similar articles Full article
3. Frilling A, Tecklenborg K, Gorges R, et al: Preoperative diagnostic value of [(18)F] fluorodeoxyglucose positron emission tomography in patients with radioiodine-negative recurrent well-differentiated thyroid carcinoma. Ann Surg 234:804-811, 2001. Medline Similar articles Full article
4. Haugen BR, Ridgway EC, McLaughlin BA, McDermott MT: Clinical comparison of whole-body radioiodine scan and serum thyroglobulin after stimulation with recombinant human thyrotropin. Thyroid 12:37-43, 2002.
5. Hay ID, Grant CS, Bergstralh EJ, et al: Unilateral total lobectomy: is it sufficient surgical treatment for patients with AMES low-risk papillary thyroid carcinoma? Surgery 124:958-964, 1998. Full article
6. Moley JF, DeBenedetti MK: Patterns of nodal metastases in palpable medullary thyroid carcinoma: Recommendations for extent of node dissection. Ann Surg 229:880-887, 1999. Medline
7. Rodriguez GJ, Balsalobre MD, Pomares F, et al: Prophylactic thyroidectomy in MEN 2A syndrome: Experience in a single center. J Am Coll Surg 195:159-166, 2002.
8. Singer PA, Cooper DS, Daniels GH, et al: Treatment guidelines for patients with thyroid nodules and well-differentiated thyroid cancer. American Thyroid Association. Arch Intern Med 156:2165-2172, 1996. Medline Similar articles Full article
9. Sivanandan R, Soo KC: Pattern of cervical lymph node metastases from papillary carcinoma of the thyroid. Br J Surg 88:1241-1244, 2001. Medline
10. Stojadinovic A, Hoos A, Ghossein RA, et al: Hurthle cell carcinoma: A 60-year experience. Ann Surg Oncol 9:197-203, 2002. Full article
11. Stojadinovic A, Shaha AR, Orlikoff RF, et al: Prospective functional voice assessment in patients undergoing thyroid surgery. Ann Surg 236:823-832, 2002. Medline Similar articles Full article
12. Udelsman R, Westra WH, Donovan PI, et al: Randomized prospective evaluation of frozen-section analysis for follicular neoplasms of the thyroid. Ann Surg 233:716-722, 2001.

1. Why are penetrating neck wounds unique?

Show answer
Although comprising only a small percentage of body surface area, the neck contains a heavy concentration of vital structures.

2. What constitutes a penetrating neck wound?

Show answer
Violation of the platysma muscle defines a penetrating neck wound. This investing fascial layer of the neck is superficial to vital structures. If the platysma is not penetrated, the wound is managed as a simple laceration.

3. Identify the boundaries of the three zones of the neck.

Show answer
Zone I extends from the sternal notch to the cricoid cartilage.
Zone II extends from the cricoid cartilage to the angle of the mandible.
Zone III comprises the area cephalad to the angle of the mandible.
These zones have distinct management implications.

4. Which side of the neck is more likely to be injured?

Show answer
The left side because most assailants are right-handed.

5. Do gunshot wounds and knife wounds cause the same relative injuries?

Show answer
Gunshot wounds generally tend to inflict more tissue damage (see Table 20-1).
Table 20-1. GUNSHOT VERSUS TAB WOUNDS

6. What are the priorities in the management of penetrating neck trauma?

Show answer
The ABCs (airway, breathing, and circulation) are the first priority in every trauma patient. Patients should be intubated orally, although cricothyrotomy may be necessary with an extensive neck wound. Although the patient may present with a patent airway, early elective airway control is advisable in patients with expanding hematomas. Pneumothoraces or hemothoraces may be associated with these injuries depending on the trajectory. While hemorrhage is being controlled with direct pressure, IV access is secured with two large-bore peripheral lines.

7. How should bleeding be controlled at the accident scene and in the emergency department?

Show answer
Direct pressure is nearly always successful, even for major arterial lesions. Do not blindly place clamps because the risk of injury to vital structures is high.

8. Should you explore the wound in the trauma bay?

Show answer
Only if the patient is asymptomatic and there has been no evidence of hemorrhage. Probing the wound may dislodge a clot, causing marked hemorrhage.

9. What physical signs are consistent with significant injury?

Show answer
Ongoing hemorrhage from the wound, expanding or pulsatile hematoma, hemoptysis, hematemesis, neurologic deficits, dysphagia, dysphonia, hoarseness, and stridor mandate an early trip to the operating room.

10. How often do patients with crepitus (in the neck) have a significant injury?

Show answer
One third of patients with crepitus have an injury of the pharynx, esophagus, larynx, or trachea. In two thirds of these patients, however, the air has been introduced through the wound entrance site, and there is no significant underlying injury.

11. What is selective management of penetrating neck trauma?

Show answer
Previously, operative exploration was advocated for all zone II injuries violating the platysma; this approach has lost support. With 50% of penetrating neck wounds not associated with significant injury, exploration is not mandatory. Alert and asymptomatic patients are evaluated with a combination of diagnostic studies (see later) or are observed expectantly with frequent serial physical examinations.

KEY POINTS: SELECTIVE MANAGEMENT OF PENETRATING INJURIES TO ZONE II

1. Penetrating injury implies violation of the platysma.
2. Mandatory exploration of all zone II injuries is not necessary since 50% of wounds are not associated with significant injury.
3. Alert and asymptomatic patients should be observed expectantly for at least 24 hours.
4. Symptomatic patients (exsanguinations or expanding hematoma) proceed to the operating room for exploration.
5. Aerodigestive symptoms (e.g., stridor, dysphonia) mandate further diagnostic testing: laryngoscopy, bronchoscopy, and esophagram.

12. Should arteriography be performed on all patients?

Show answer
Preoperative arteriograms generally are performed in hemodynamically stable patients with zone I injuries. Their value is to identify injuries to major vessels in the thoracic outlet that may require a thoracic operative approach. Wounds in zone III are treated best by angioembolization if there is evidence of significant bleeding.

13. What is the value of other diagnostic studies, such as esophagography, esophagoscopy, laryngoscopy, and bronchoscopy?

Show answer

Routine use of esophagography, bronchoscopy, and laryngoscopy has been advocated in zone I and selected nonoperatively managed zone II patients. Esophagoscopy is combined with esophagography if esophageal injury is suspected; if water-soluble contrast material does not show a leak, barium is used. Missed esophageal injuries can be deadly, with a 20% mortality rate if diagnosis is delayed only 12 hours. Angiography remains the gold standard for diagnosis of arterial injury, and this modality may be therapeutic for zone III injuries (zone III is tough to expose surgically). Intraoperative endoscopy with insufflation may be used provocatively to show an air leak and associated esophageal injury.

14. What is the role of CT?

Show answer
If patients have a high-risk trajectory (i.e., transcervical gunshot wounds), CT may identify the “line of fire” and help determine the need for angiography (see Figure 20-1).

Figure 20-1 Management of penetrating neck trauma.

15. Should an asymptomatic patient with a penetrating neck wound be sent home from the emergency department?

Show answer
No. Life-threatening penetrating neck wounds initially may be difficult to sort out; the safest policy is to observe all patients in the hospital for at least 24 hours.

References
WEB SITES

1. http://www.acssurgery.com/abstracts/acs/acs0504.htm
2. http://www.surgery.ucsf.edu/eastbaytrauma/Protocols/ER%20protocol%20pages/penetrneck.htm

BIBLIOGRAPHY
1. Albuquerque FC, Javedan SP, McDougall CG: Endovascular management of penetrating vertebral artery injuries. J Trauma 53:574-580, 2002. Medline Similar articles Full article
2. Atteberry LR, Dennis JW, Menawat SS, Frykberg ER: Physical examination alone is safe and accurate for evaluation of vascular injuries in penetrating zone II neck trauma. J Am Coll Surg 179:657-662, 1994. Medline Similar articles
3. Biffl WL, Moore EE, Rehse DH, et al: Selective management of penetrating neck trauma based on cervical level of injury. Am J Surg 174:678-682, 1997. Medline Similar articles Full article
4. Demetriades D, Velmahos G, Asensio JA: Cervical pharygoesophageal and laryngotracheal injuries. World J Surg 25:1044-1048, 2001. Medline Similar articles Full article
5. Gracias VH, Reilly PM, Philpott J, et al: Computed tomography in the evaluation of penetrating neck trauma: A preliminary study. Arch Surg 136:1231-1235, 2001. Medline Similar articles Full article
6. Hirshberg A, Wall MJ, Johnston RH, et al: Transcervical gunshot injuries. Am J Surg 167:309, 1993.
7. Mazolewski PJ, Curry JD, Browder T, Fildes J: Computed tomographic scan can be used for surgical decision making in zone II penetrating neck injuries. J Trauma 51:315-319, 2001.
8. McIntyre WB, Blaard JL: Cervicothoracic vascular injuries. Semin Vasc Surg 11:232-242, 1998. Medline Similar articles

1. What is an abdominal aortic aneurysm (AAA)?

Show answer
A ≥ 50% increase in normal aortic diameter. Normal infrarenal aortic diameter is 2.0 cm for men. A definition of AAA as an aorta ≥ 3.0 cm in diameter is appropriate.

2. What is the incidence of AAA?

Show answer

* 3% in unselected adult patients screened with ultrasound
* 5% in patients with known coronary artery disease
* 10% in patients with known peripheral vascular disease

3. What is the etiology of AAA?

Show answer
Elastin is the primary load-bearing element of the aorta. In the normal human aorta, there is a gradual reduction in the amount of elastin present in the distal compared with the proximal aorta. Elastin fragmentation and degeneration are observed histologically in AAA walls. These observations help explain the predilection of AAAs in the infrarenal aorta. Absence of vasa vasorum in the infrarenal aorta has led to the suggestion of a nutritive deficiency. The degradation of aortic media in aneurysmal disease implies a disrupted balance between proteolytic enzymes and their inhibitors.

4. Do AAAs have a genetic component?

Show answer
Multiple reports describe a familial subgroup of AAAs. Therefore, screening of AAA patients’ first-degree relatives who are 50 years old and older makes sense. Two prospective studies demonstrated that approximately 30% of these relatives also harbor an AAA. The proposed genetic defect has been linked to abnormal type III collagen.

5. Are patients with AAA prone to aneurysms in other vascular beds?

Show answer
Yes. Forty percent of patients with a popliteal artery aneurysm harbor an AAA. Seventy-five percent of patients with a femoral artery aneurysm also have an AAA. Patients with thoracic aneurysms have a 20% chance of having a simultaneous AAA. Five percent of patients develop aortic aneurysms proximal to their graft at ≥ 5 years after infrarenal AAA repair.

6. Can AAAs reliably be detected on physical examination?

Show answer
No. The aortic bifurcation is at the level of the umbilicus. Therefore, the pulsatile mass of an AAA is located in the epigastrium. Thus, only relatively large AAAs can be detected in thin patients.

7. Can AAAs be detected by radiography?

Show answer
Plain abdominal or lumbar spine radiographs can detect occult AAA in about 20% of cases. A thin rim of calcification identifies the aneurysmal aortic wall. The majority of AAAs contain insufficient calcium to be visualized by radiography.

8. Which imaging method is the best for screening patients for AAA?

Show answer
Abdominal ultrasound (US) permits measurement accuracy within 0.3 cm and data in both cross-sectional and longitudinal dimensions.

9. What is the best single imaging modality to plan AAA repair?

Show answer
The contrast-enhanced computed tomography (CT) scan is the best one. Diameter measurements are accurate within 0.2 cm. Venous anomalies (i.e., retroaortic or circumaortic left renal vein, inferior vena cava duplication, and left-sided inferior vena cava) that dramatically alter the operative approach are well visualized on CT. Although CT is excellent at detecting aneurysmal rupture or leak (92% accuracy and 100% specificity), it is less useful for predicting suprarenal aneurysm involvement (sensitivity, 83%; specificity, 90%; positive predictive value, 48%).

10. What is the manifestation of a symptomatic AAA?

Show answer
Acute low back pain is the most common presenting symptom (82%), but only one third of AAAs are diagnosed before rupture. A hypotensive elderly man with acute onset of low back pain has a leaking AAA until proven otherwise.

11. What is the appropriate management of a patient suspected of a ruptured AAA?

Show answer
Just before emergent surgical exploration, patients who are hemodynamically unstable with a pulsatile abdominal mass should have an electrocardiogram to rule out myocardial infarction.

12. Should all patients presenting with AAA rupture undergo repair?

Show answer
Patients in profound shock or cardiac arrest at the time of presentation have little chance of survival. Extreme age, dementia, metastatic cancer, and other severe end-stage medical problems should force you to reassess this allocation of medical resources.

13. Do all patients with ruptured AAAs make it to surgery?

Show answer
Approximately half of patients with a ruptured AAA die before reaching the hospital. One fourth of those who make it to the hospital die before they can be brought to the operating room. Therefore, only 25% of patients make it to surgery.

14. How is a ruptured AAA treated operatively?

Show answer
The patient should not be anesthetized until completely prepped and draped and ready for immediate incision because the blood pressure may decrease dramatically upon induction of anesthesia. Rapid proximal aortic control is the key to successful outcome of operations for ruptured AAA. This can be at the diaphragm (in an unstable patient, with free intraperitoneal bleeding or a retroperitoneal hematoma that extends proximal to the left renal vein) or at the infrarenal aortic segment (in a stable patient with a lower retroperitoneal hematoma). Intraluminal balloon occlusion of the aorta is an option with free intraperitoneal rupture. As soon as control is obtained, the patient is resuscitated and clamps are moved to the more standard infrarenal location. Distal control can also be obtained with balloons or packs to prevent iliac venous injury.
KEY POINTS: ABDOMINAL AORTIC ANEURYSM

1. An AAA is defined as a ≥ 50% increase in normal aortic diameter.
2. Forty percent of patients with a popliteal artery aneurysm harbor an AAA.
3. CT is the single best imaging modality to plan an AAA repair.
4. AAA should be repaired electively when the size reaches 5.5 cm in diameter.

15. How should patients with symptomatic nonruptured AAAs be managed?

Show answer
Symptomatic AAAs are rapidly expanding and at high risk for rupture. Therefore, most vascular surgeons agree that symptomatic but intact AAAs should be repaired expeditiously (as early as is conveniently possible).
16. Are there any alternatives to open surgical repair for ruptured AAA? Show answer
Endovascular prosthetic grafts have been successfully placed in high-risk patients with symptomatic AAAs or contained ruptures both in the aortic and aortoiliac position.

17. What are the rupture rates of AAAs?

Show answer
A 5-cm diameter AAA has an annual rupture risk of < 1%. The risk of AAA rupture increases with size. Annual rupture risk is 10% for a 6-cm AAA and 30% for AAAs > 7 cm.

18. How fast do AAAs enlarge?

Show answer
The average expansion rate of all AAAs is 0.4 cm/year. However, 20% of all AAAs demonstrate no change in size over time. Conversely, 20% expand at a rate > 0.5 cm/year. Rapid expansion (0.5 cm/6 months) is considered to be predictive of rupture and an indication for repair.

19. When are angiograms helpful in the diagnostic workup for AAA?

Show answer
Traditionally, angiography has been indicated in patients when there is concern regarding the extent of the proximal neck, concomitant visceral occlusive disease, renal artery anomalies, a prior colectomy with need to visualize the visceral circulation, or lower extremity occlusive or aneurysmal disease.

20. What is the difference between extraperitoneal and transabdominal approach?

Show answer
Elective aortic graft placement can be carried out equally well via a transperitoneal or extraperitoneal approach. The former provides better pelvic exposure. The extraperitoneal approach provides superior exposure of the suprarenal aorta and facilitates postoperative pulmonary management.

21. What are endografts? Are they durable?

Show answer
Endovascular grafts are graft-covered stents that are placed via the femoral artery by interventional (i.e., radiographic) methods to exclude the aneurysm without the need for an abdominal incision or cross clamping the aorta. Multiple different series of successful endovascular AAA repair have been reported. Successful endograft placement has been reported in a wide variety of high-risk operative candidates. Many vascular surgeons and interventionalists are making aortic endograft placement their preferred treatment for patients with AAAs. The major drawbacks are late leaks or rupture from the graft, the cost of the procedure, and the need for long-term patient follow-up.

22. At what size should asymptomatic AAAs be repaired electively?

Show answer
They should be repaired electively when the AAA reaches 5.5 cm in diameter. The only benefit for repair of an asymptomatic AAA is to prevent subsequent rupture and death. Therefore, all candidates for elective repair must expect to live at least 5 years.

23. What are the technical aspects of AAA surgery?

Show answer
The two important decisions are the location of arterial clamps and the type of graft to place. The majority of cases can be managed by placing the arterial clamp below the renal arteries. This avoids prolonged ischemia to the kidneys. The aneurysm is opened after clamping proximally and distally. Lumbar artery orifices are oversewn to prevent bleeding from collateral arteries. The inferior mesenteric artery is often occluded, but when it is patent and not vigorously backbleeding, it may require reimplantation.

24. What are the major noncardiac complications of AAA repair?

Show answer
Renal failure (elevation in creatinine) and intestinal ischemia (bloody diarrhea).

References
WEB SITE
http://www.acssurgery.com
BIBLIOGRAPHY
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