13. Is HLA (human leukocyte) matching still important?

Show answer
It is somewhat important. Historically, HLA matching was an important consideration when matching cadaver kidneys to recipients. With today’s improved immunosuppressive agents, many transplant surgeons believe that HLA matching is no longer critical. Six antigen match kidneys are still shared nationally and do enjoy some improvement in long-term graft survival. Donor organ quality remains the primary determinant in how well the transplanted organ functions. For example, a poorly matched living-donor kidney will still usually outlast a well-matched cadaveric kidney.

14. Does pancreas transplantation halt the progression of diabetic disease?

Show answer
This is still unproven. Logically, we would expect it to. Regression of neuropathy and eye dysfunction has been reported. Recently, long-term recipients have exhibited some regression of microscopic nephropathy.

15. Are islet cell transplants the answer in the future?

Show answer
Probably, although this has been frustratingly slow to achieve. Recent protocols using new immunosuppressive regimens and new islet cell isolation techniques have shown promise, but long-term data are still not widely available. The process requires that isolated islet cells be extracted from a donor pancreas. These cells are then injected into the portal vein, lodge in the liver, and produce insulin. Theoretically, patients achieve the benefit of a pancreas transplant without the surgical risk.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Bartlett ST: Laparoscopic donor nephrectomy after seven years. Am J Transpl 2:896-897, 2002. Full article
2. Donovitch G: Handbook of Kidney Transplantation, 3rd ed. Philadelphia, Lippincott Williams & Wilkins, 2001.
3. Fioretto P, Steffes MW, Sutherland DER, et al: Reversal of lesions of diabetic nephropathy after pancreas transplantation. N Engl J Med 339:69-75, 1998. Medline Similar articles Full article
4. Morris JP: Kidney Transplantation: Principles and Practice, 5th ed. Philadelphia, W.B. Saunders, 2001.

1. What are the goals of hand repair?

Show answer
Functional considerations override cosmesis in the treatment of hand trauma. There are no minor hand injuries. Initial diagnosis and management determine the final result; expert secondary repair cannot overcome primary errors in diagnosis or decision making.

2. What determines the final outcome of a hand injury?

Show answer
It is determined by minimal sacrifice of tissue and primary healing accomplished by early wound closure. Minimization of scar tissue by control of edema, prevention of infection, early wound closure, and vigorous physical therapy produce the optimal functional outcome.

3. What factors influence treatment of hand trauma?

Show answer
Mechanism, location, and timing of injury; hand dominance; occupation; age; and general health of the patient.

4. How common are occupational hand injuries?

Show answer
Hand injuries result in more days lost from work than any other type of occupational injury.

5. What are the essentials of examination of the hand?

Show answer
Inspection of position, color, and temperature often reveals the injury. Location suggests possible injury to underlying structures. Motor, sensory, and Doppler ultrasonic examination are confirmatory. All injuries must be radiographed, and surgical exploration provides the definitive diagnosis.

6. How and where should hand injuries be explored?

Show answer
Hand wounds should be explored under tourniquet control with adequate analgesia using delicate instruments in a well-lighted surgery suite. Visual magnification is usually mandatory.

7. How is emergency hemostasis of injured hands achieved?

Show answer
In the acute setting (outside the operating suite), no tourniquet should be applied, and there should be no blind clamping of any structures. Hemostasis may be achieved by elevation of the extremity and with direct compression of the wound. This approach prevents injury to delicate underlying structures that are tough to see.

8. How are fingertip injuries treated?

Show answer
If < 1 cm of pulp is disrupted, the wound will heal spontaneously with daily cleansing and dressing with nonadherent, moist gauze. Larger defects may require a skin graft, which can often be provided by defatting the amputated piece. Bone exposure necessitates flap coverage if digital length is to be maintained. Digital nerves cannot be repaired distal to the distal interphalangeal (DIP) joint.

9. What is the classification system for fingertip amputations?

Show answer

Classification for fingertip amputations is based on the amount of remaining sensate volar skin. Although the favorably angulated amputation commonly removes some nail and bone, the volar skin is available for easy coverage. This amputation type is “favorable” for treatment by dressings only, allowing wound repair by contraction and epithelialization. The volarly angulated amputation angle is “unfavorable” for conservative management and usually requires a reconstructive procedure. (Image from Ditmars DM Jr: Fingertip and nail bed injuries. In Kasdan ML (ed): Occupational Hand and Upper Extremity Injuries and Disease. Philadelphia, Hanley & Belfus, 1991, with permission.) (See Figure 34-1.)

Figure 34-1 Fingertip amputations.

10. How are nail bed injuries repaired?

Show answer
Repair of the disruption of the germinal matrix must be meticulously approximated under magnification and the nail bed splinted, preferably with the avulsed part. Subungual hematomas should be evacuated by a hot-tipped paperclip or battery-powered electric cautery. Repair of the disruption of the sterile eponychial fold must be maintained for 3 weeks with Xeroform gauze or with the original nail. Often, nail bed disruption cannot be diagnosed without removal of the nail.

11. What is the initial management of flexor tendon?

Show answer
Flexor tendon laceration is not an emergency, and repair should not be undertaken in the emergency department. If a hand surgeon is unavailable, the wound should be copiously irrigated and sutured and prophylactic antibiotics instituted. This injury can wait for definitive repair.

12. What is the proper management of an open fracture?

Show answer
Open fractures should be cultured and then undergo copious lavage with normal saline or Ringer’s lactate. Broad-spectrum antibiotic coverage should be instituted, and the hand should be splinted in the position of function with a bulky dressing.

13. What is the proper treatment for hand infection?

Show answer
The extremity should be immobilized and elevated, and parenteral antibiotics should be given. The patient should be immediately referred for possible surgical drainage.

14. What is the proper management of human bites?

Show answer
After cleansing of the wound, a radiograph should be taken. The wound should be left open-never closed. Antibiotics should be started, and the wound should be rechecked at 24 and 48 hours. If evidence of infection is present, parenteral antibiotics should be instituted and referred for possible surgical drainage. The so-called fight bite occurs over the metacarpophalangeal (MCP) joint or proximal interphalangeal joint when a clenched fist is impaled on the front teeth of an adversary. This often inoculates the MCP joint with anaerobic streptococci. When infection is diagnosed, immediate arthrotomy and lavage should be performed.

15. How are injection injuries treated?

Show answer
Despite their innocuous appearance, injection injuries may cause profound destruction of hand structures. Any such injury requires immediate hospitalization with prompt and extensive decompression, drainage, and debridement.

KEY POINTS: CARPAL TUNNEL SYNDROME

1. Symptoms: numbness, tingling, pruritus of the palm, thumb, middle, and index fingers.
2. Mechanical cause is compression of median nerve and carpal tendons.
3. Women are affected twice as often as men; the syndrome is more common after 40 years of age.
4. Predilection for people who perform repetitive manual labor.

16. What is carpal tunnel syndrome (CTS)?

Show answer
CTS is the most common peripheral compression neuropathy; it is signaled by numbness and tingling of the hand.

17. Is CTS more common in older or younger people? Men or women?

Show answer
CTS is more common in people older than age 40 years, but an increasing number of young people with CTS have been reported in recent years, usually those whose jobs involve repetitive manual labor. Women are affected approximately twice as often as men.

18. What are the most preventable causes of deformity in hand injuries?

Show answer
Edema and infection lead to increased scarring and restricted function. Prolonged immobilization in a poor position also impairs function, as does delayed skin closure. Failure to obtain a radiograph leads to a missed diagnosis with delay in recognition of an injury.

19. What is the proper emergency department treatment of all hand injuries?

Show answer
The patient should be sedated and the wound cultured and irrigated. A thorough examination must be performed and a sterile compression dressing placed. The upper extremity should be splinted, tetanus prophylaxis should be administered, and broad-spectrum antibiotic coverage should be instituted for crush avulsion or heavily contaminated wounds. Radiographs of the hand should always be obtained.

20. What are the guidelines for replantation of an amputated finger?

Show answer
There are no absolute guidelines. A microsurgeon who is a member of a replantation team should be consulted. If replantation is planned, parts should not be immersed directly in water or put directly on ice or dry ice. The part should be copiously irrigated, wrapped in a moist sponge, and placed in a sterile plastic container; the plastic container should be placed in an ice-water slurry for transport.

References
WEB SITE

* http://www.ninds.nih.gov
o Search: carpal tunnel

BIBLIOGRAPHY
1. Dunn R, Watson S: Suturing versus conservative management of hand lacerations. Hand lacerations should be explored before conservative treatment. Comment on Br Med J 325(7359):299, 2002. Br Med J 325(7372):1113, 2002.

2. Hansen TB, Carstensen O: Hand injuries in agricultural accidents. J Hand Surg 24B:190-192, 1999.
3. Irvine AJ: Suturing versus conservative management of hand lacerations. Incisions are not lacerations. Comment on Br Med J 325(7359):299, 2002. Br Med J 325(7372):1113, 2002; author reply 325(7372):1113, 2002.
4. Lee SJ, Montgomery K: Athletic hand injuries. Orthop Clin North Am 33:547-554, 2002. Medline Similar articles Full article
5. McAuliffe JA: Hand care in the new millennium: Surgeons’ perspective. J Hand Ther 12:178-181, 1999. Medline Similar articles
6. Riaz M, Hill C, Khan K, Small JO: Long-term outcome of early active mobilization following flexor tendon repair in zone 2. J Hand Surg 24B:157-160, 1999.
7. Taras JS, Lamb MJ: Treatment of flexor tendon injuries: Surgeons’ perspective. J Hand Ther 12:141-148, 1999. Medline Similar articles
8. Van der Molen AB, Matloub HS, Dzwierzynski W, Sanger JR: The hand injury severity scoring system and workers’ compensation cases in Wisconsin, USA. J Hand Surg 24B:184-186, 1999.

• Postoperative fever workup
• opss sepsis 14 days
• solitary pulmonary nodule breast cancer patient
• honeymoon period bochdalek
• relation between breathlessness and total thyroidectomy
• colon surgery diverticulitis
• Hematest-positive NGT
• nonoperative management of spleen injury
• when is the parental nutrion discontinued
• grading for splenic laceration
• having a solitary nodule with calcium flecks
• how many milliequivalents in gatorade

2. What causes hyperthyroidism?

3. How should hyperthyroidism be investigated?

Show answer
A thyroid stimulating hormone (TSH) level is the best intial test. A low TSH with a high serum level of thyroxine (T4) or triiodothyronine (T3) is diagnostic. A high TSH with an increase in free T4 indicates the rare patient with a thyrotropin-producing pituitary tumor.
After the diagnosis of hyperthyroidism is made, the radioactive iodine uptake (RAIU) can differentiate the many causes.

4. What are the three treatment options?

Show answer
Antithyroid drugs (ATD), radioiodine, and surgery.

5. Which drugs are useful for the treatment of hyperthyroidism? What are their mechanisms of action?

Show answer
Methimazole and propylthiouracil (PTU) are the mainstays of treatment. The goal of treatment is remission of Graves’ disease during therapy or euthyroidism before treatment with radioiodine or surgery. Both drugs inhibit organification of iodine and coupling of iodothyronines. PTU also inhibits the peripheral monodeiodination of T4 to T3. Treatment is started with 20 mg/day of methimazole or 100 mg of PTU 3 times/day. The dose may be reduced after 6 weeks of treatment as the patient shows clinical and biochemical improvement. Therapy is usually maintained for 2 years. Patients must be monitored for side effects, which include rash, pruritus, agranulocytosis, hepatitis, cholestatic jaundice, and lupus-like syndrome.

Beta-adrenergic antagonists ameliorate the signs and symptoms of disease. They should not be used alone except for short periods before radioiodine or surgical therapy. Nadolol (80 mg/day) and atenolol (100 mg/day) are the most common agents.
Iodine given as Lugol’s solution (5% iodine and 10% potassium iodide in water, 0.3 mL/day) or potassium iodide (60 mg 3 times/day) inhibits the release of thyroid hormone. It is useful for short-term therapy in preparation for surgery, after radioiodine therapy to hasten the decrease in hormone levels, and for treatment of thyroid storm.

6. What are the indications for and outcome of drug treatment?

Show answer
ATD therapy is reserved for mild hyperthyroidism and a small gland. Long-term remission of Graves’ hyperthyroidism during antithyroid drug therapy occurs in 50% of patients. Relapse is most common in the first 6 months after cessation of treatment.

7. What is the regimen of radioiodine treatment?

Show answer
Radioiodine is the most common therapy. The usual dose of radioiodine is 10 mCi. If hyperthyroidism is not cured, the dose should be repeated in 6 months. Pretreatment with antithyroid drug therapy should achieve a euthyroid state. Steroids prevent progression of ophthalmopathy. Prednisone is used at a dose of 0.5 mg/kg body weight, starting 3 days after radioiodine therapy and continuing for 1 month. The dose is tapered over 2 months.
Pregnancy is an absolute contraindication. Women of childbearing age should be evaluated with a pregnancy test before treatment and should avoid pregnancy for 6 months after treatment. Evidence indicates that radioiodine may exacerbate ophthalmopathy.

8. What is the outcome of radioiodine treatment?

Show answer
Euthyroidism is not achieved for months after treatment. After euthyroidism is achieved, recurrence of hyperthyroidism is rare. Hypothyroidism, the only serious side effect, is dose dependent. It occurs at a rate of 3% per year, affecting 50% of patients at 10 years, and nearly 100% at 25 years.

9. What are the indications for thyroidectomy for hyperthyroidism?

Show answer

* Pregnant patients who are difficult to treat medically
* Patients with large goiters and low radioiodine uptake
* Children
* Noncompliant patients
* Patients with nodules suspected to be cancerous
* Patients with compression of the trachea or esophagus
* Patients with cosmetic concerns
* Patients with ophthalmopathy

10. How should patients be prepared for surgery? Show answer
Any patient with hyperthyroidism should be rendered euthyroid before surgery. Patients may be treated with antithyroid medication and potassium iodine. Beta-adrenergic antagonists should also be used alone or in combination with the above regimen.

11. What is the extent of thyroidectomy?

Show answer
The two surgical options for Graves’ disease are subtotal thyroidectomy or near-total thyroidectomy. The goal of subtotal thyroidectomy is to preserve 8 g of well-vascularized thyroid tissue to avoid hypothyroidism. Because of the small risk of recurrence (10%), however, some surgeons prefer near-total thyroidectomy. In Plummer’s disease, lobectomy or partial thyroidectomy for unilateral lesions and contralateral subtotal thyroidectomy for multiple lesions render the patient euthyroid.

12. What is the incidence of hypothyroidism after surgery?

Show answer
All patients having a near-total thyroidectomy become hypothyroid and need thyroxine replacement. Hypothyroidism occurs in 50% of patients with subtotal thyroidectomy.
KEY POINTS: HYPERTHYROIDISM

1. A thyroid-stimulating hormone (TSH) level is the best initial test.
2. Methimazole and propylthiouracil are the mainstays of medical treatment.
3. The two surgical options for Graves’ disease are subtotal thyroidectomy and near-total thyroidectomy.

13. What is the appropriate treatment for toxic nodular goiter?

Show answer
Hyperthyroidism caused by toxic nodular goiter is permanent and without spontaneous remission; antithyroid drugs are not appropriate long-term therapy. Radioiodine is the most common form of therapy. Larger doses (50 mCi) minimize the risk of persistent hyperthyroidism in such patients, who tend to be older and to have prominent cardiovascular symptoms of hyperthyroidism.

14. What is the appropriate treatment for hyperthyroidism caused by thyroiditis?

Show answer
Subacute thyroiditis should be suspected if the patient has pain and tenderness in the thyroid region. The hyperthyroidism is usually mild and of short duration (i.e., weeks). Patients are treated with a beta-adrenergic antagonist and salicylate or glucocorticoid. Hypothyroidism may occur but is usually not permanent.

15. What is the appropriate treatment for thyroid storm?

Show answer
Thyrotoxic crisis should be treated in the intensive care unit. General measures include hydration, antipyresis (acetaminophen), and nutrition. Specific measures include inhibition of T4 synthesis and conversion to T3 with PTU at a dose of 100 mg orally, via nasogastric tube, or rectally every 6 hours. Iodides inhibit T4 release (saturated solution of potassium iodide, 5 drops by mouth or nasogastric tube every 6 hours). Steroids (dexamethasone, 2 mg every 6 hours) also inhibit T4 release and conversion to T3. Beta-adrenergic antagonists (propranolol or esmolol) may control cardiovascular manifestations. The last-resort management option is T4 removal by plasmapheresis, hemoperfusion, or dialysis.

16. Who performed the first thyroidectomy?

Show answer
Johann von Mikulicz-Radecki performed the first thyroidectomy in 1885.

17. Which surgeon won the Nobel Prize for his work with thyroid disease?

Show answer
Theodor Kocher won the Nobel Prize in medicine in 1909. He was successful in reducing the high mortality rate of thyroidectomy to less than 1%. His most significant achievement was in describing postoperative hypothyroidism as cachexia strumipriva.

References
BIBLIOGRAPHY
1. Bartalena L, Marcocci C, Bogazzi F, et al: Relation between therapy for hyperthyroidism and the course of Graves’ ophthalmopathy. N Engl J Med 338:73-78, 1998. Medline Similar articles Full article
2. David E, Rosen IB, Bain J, et al: Management of the hot thyroid nodule. Am J Surg 170:481-483, 1995. Medline Similar articles Full article
3. Franklyn JA: The management of hyperthyroidism. N Engl J Med 330:1731-1738, 1994. Medline Similar articles Full article
4. Franklyn JA, Daykin J, Drolc Z, et al: Long-term follow-up of treatment of thyrotoxicosis by three different methods. Clin Endocrinol (Oxf) 34:71-76, 1991. Medline Similar articles Full article
5. Kang AS, Grant CS, Thompson GB, van Heerden JA: Current treatment of nodular goiter with hyperthyroidism (Plummer’s disease): Surgery versus radioiodine. Surgery 132:916-923, 2002. Medline Similar articles Full article
6. Miccoli P, Vitti P, Rago T, et al: Surgical treatment of Graves’ disease: Subtotal or total thyroidectomy? Surgery 120:1020-1024, 1996. Full article
7. Singer PA, Cooper DS, Levy EG, et al: Treatment guidelines for patients with hyperthyroidism and hypothyroidism. Standards of Care Committee, American Thyroid Association. JAMA 273:808-812, 1995. Similar articles Full article
8. Torring O, Tallstedt L, Wallin G, et al: Graves’ hyperthyroidism: Treatment with antithyroid drugs, surgery, or radioiodine: A prospective, randomized study. Thyroid Study Group. J Clin Endocrinol Metab 81:2986-2993, 1996. Medline Similar articles Full article
9. Weetman AP: Graves’ disease. N Engl J Med 343:1236-1248, 2000.
10. Witte J, Goretzki PE, Dotzenrath C, et al: Surgery for Graves’ disease: Total versus subtotal thyroidectomy: Results of a prospective randomized trial. World J Surg 24:1303-1311, 2000. 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.

NUTRITIONAL ASSESSMENT

1. What does a nutritional assessment include? Show answer

1. The medical and surgical history is used to establish preexisting (comorbid) conditions, metabolic stress, and alterations in organ function.
2. The physical examination focuses on the muscle mass, adipose stores, skin integrity, and hydrational state.
3. Laboratory data include the chemistry profile (Na, K, CO2, Cl, BUN, creatinine, glucose), ionized Ca, serum PO4, and Mg, complete blood count (CBC) with differential, arterial blood gases (ABGs; to assess acid-base status and CO2 retention), albumin, transferrin, prealbumin, and urinary nitrogen.
4. The drug profile can reveal agents that affect the metabolism of nutrients (insulin, levothyroxine, corticosteroids) or alter energy expenditure (beta-blockers, Diprivan).
5. Anthropometric data include height and weight; skinfold testing with calipers is only useful once edema has resolved but is rarely used in the acute care setting. Although information on adipose reserve, body cell mass, intra- and extracellular water, and third space fluid may be elucidated, standards for bioelectrical impedance analysis (BIA) have yet to be determined.
6. A nutrition history reveals preexisting nutritional practices.
7. The social history explores economic data or substance abuse behaviors and may predict the likelihood of adequate home care for the patient upon discharge.

2. What are primary and secondary malnutrition?

Show answer
Primary malnutrition is the consumption of inadequate kilocalories, protein, vitamins, or minerals. It may occur because of poor food choices, anorexia, poverty, alcoholism, suboptimal support regimens, or after bariatric surgery. Secondary malnutrition may occur even when adequate food is infused or consumed. It results from organ dysfunction (hypoalbuminemia with cirrhosis), malabsorption (Crohn’s disease), immobility (muscle wasting), drug therapy (insulin resistance with corticosteroids), or the inflammatory response (reprioritization of hepatic synthesis of acute phase instead of constitutive proteins).

3. What is the significance of serum proteins in nutritional assessment?

Show answer

Table 8-1. SERUM PROTEINS

TIBC = total iron-binding capacity.

KEY POINTS: HALF-LIVES OF SERUM PROTEINS USED AS NUTRITIONAL MARKERS

1. Pre-albumin: 2-4 days
2. Transferrin: 8-10 days
3. Albumin: 20-21 days

The most readily available proteins for nutritional assessment are albumin, transferrin, and prealbumin, which are all constitutively produced in the liver. Their half-lives are 20-21 days, 10-12 days, and 2-4 days, respectively. The level of all three plummets shortly after injury or surgery as the liver reprioritizes the production of acute phase proteins. Then, as inflammation, infection, and stress begin to resolve, the liver resumes production of constitutive proteins. Adequate kilocalories and protein facilitate this process. Because of their shorter half-lives, prealbumin and transferrin are most useful in the intensive care unit (ICU) setting and should be limited to patients with creatinine clearance > 50 mL/min. Levels of both proteins may be depleted in patients with hepatic failure or cirrhosis because of decreased synthetic function. Prealbumin travels in the circulation bound to retinol-binding protein (RBP) and vitamin A. Levels of prealbumin may be elevated in renal failure despite nutritional compromise, because of decreased catabolism and decreased excretion of RBP. Transferrin is elevated with iron depletion, independent of the effects of nutrition. (See Table 8-1.)

4. What is the significance of urinary nitrogen in nutritional assessment?

Show answer
Total urinary nitrogen (TUN) is the most reliable indicator of nitrogen utilization and excretion in surgical ICU patients. However, urinary urea nitrogen (UUN) is more readily available in most hospital laboratories. Although TUN and UUN are nearly equal in healthy ambulatory patients, critically ill patients exhibit a poor correlation between the two. Optimal nutrition support should place a patient in 13 to 15 nitrogen balance. One may estimate the protein needs of the patient by adding:

[24 h UUN (g) + 2 g N insensible losses + 3] x 6.25 = required amount of protein (g)

The total in brackets is multiplied by 6.25 to convert nitrogen grams to protein grams. Thus, if the laboratory reported a 13-g UUN/24 hours and a 2-g N insensible loss (skin, hair, feces) + 3 g for optimal anabolism, the patient would require 18 g N × 6.25 = 112.5 g of protein for anabolism. Urinary nitrogen is not useful as a guide for nutritional prescription in hepatic failure, renal dysfunction (< 50 mL/min creatinine clearance), or recent spinal cord injury.

5. How are protein requirements determined?

Show answer
Protein need is determined based on the weight of the patient, current stress factors, extraordinary skin losses, and organ function. Although the recommended daily allowance (RDA) for protein for healthy individuals is only 0.8 g protein/kg body weight, the following guidelines may be used in surgical patients. (See Table 8-2.)
Table 8-2. PROTEIN REQUIREMENTS IN RELATION TO INJURY LEVEL

Injury Level Protein Requirement
Mild stress or injury 1.2-1.4 g/kg
Moderate stress or injury 1.5-1.7 g/kg
Severe stress or injury 1.8-2.5 g/kg

6. Should protein be severely restricted in surgical patients with hepatic failure or renal failure?

Show answer
Protein should be restricted to 0.7 g/kg in patients with encephalopathy, only if the hepatic encephalopathy produces significant clinical consequences. Only 10% of chronic liver disease patients are protein sensitive; thus, other causes of encephalopathy such as infection, constipation, and electrolyte disturbance should be explored. Otherwise, a more typical postsurgical protein load may be adopted (1.4 g/kg). In injured patients with renal failure, one must balance the need for increased protein with the need for increased dialysis. One should provide the amount of protein required and dialyze more frequently.
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7. How are kilocalorie needs determined?

Show answer
There are several methods for setting kilocalorie targets in the surgical patient: standard prediction equations, kilocalorie per kilogram estimations, and indirect calorimetry. One common prediction equation, the Harris Benedict (HBE), was developed in 1919 for use on ambulatory, fasted, healthy people. Basal energy expenditure (BEE), the number of kilocalories required at rest daily, is calculated using the following equations:

Female BEE = 655 + 9.6 (kg) + 1.8 (cm) -4.7 (age)
Male BEE = 67 + 14 (kg) + 5 (cm) – 6.7 (age)

Subsequently, the above sums are multiplied by stress factors to determine total kilocalorie goals. (See Table 8-3).
Many clinicians use a total kcal/kg goal as shown in Table 8-4.
Table 8-3. KCAL NEEDS IN RELATION TO STRESS LEVELS

Stress Level Example Kcal Needs
Mild Closed fracture, pneumonia, or splenic laceration BEE × 1.2
Moderate Bowel resection, hepatorrhaphy, or thoracotomy BEE × 1.4
Severe Major bowel perforation with resection, major open wounds,
intraabdominal abscess BEE × 1.6

Table 8-4. KCAL / KG GOALS

Patient Feeding Level (kcal/kg) Level by Indirect Calorimetry
Normal weight patients 25-30 REE† × 1.0
Underweight patients 35-40 REE × 1.2
Obese patients 20-25* REE × 0.85
Morbidly obese 10-20* REE × 0.75

†Resting energy expenditure (REE) is the measure of energy expenditure in a fed state and is generally 10% higher than BEE.
*Use adjusted weight.

8. What is indirect calorimetry?

Show answer
It is a bedside test in which the patient’s production of carbon dioxide and consumption of oxygen are measured for approximately 30 minutes until steady state is achieved. Results are inserted into the modified Weir equation:

REE = [(3.796 x VO2) + (1.214 x VCO2)] x 1440 min/day

where REE = resting energy expenditure (kcal/day), VO2 = oxygen consumption (L/min), and VCO2 = CO2 exhaled (L/min).

The chart reports the number of kilocalories the patient is predicted to consume in 24 hours and the respiratory quotient (RQ). RQ = VCO2/VO2 and provides information on the type of substrate being used. The RQs for the metabolism of fat, protein, and carbohydrate are 0.7, 0.83, and 1.0, respectively. Overfeeding results in an RQ > 1.0.
KEY POINTS: RESPIRATORY QUOTIENT

1. Defined as ratio of CO2 produced to O2 consumed
2. Easy to perform on mechanically ventilated patients
3. Identifies principal metabolic substrate used by the patient
4. Ratio for fat (0.7), protein (0.83), and carbohydrates (1.0)
5. 5. Ratio < 1 indicates starvation or underfeeding; ratio > 1 indicates overfeeding, lipogenic status
6. Increased CO2 production linked to difficulty with ventilator weaning and impaired immune response

9. When is indirect calorimetry useful?

Show answer
The test may be performed on mechanically ventilated patients as soon as they are relatively stable, with a fractional concentration of oxygen in inspired gas (FiO2) < 60% and peak end-expiratory pressure (PEEP) < 10. Studies are helpful:

* When overfeeding (e.g., in diabetes mellitus, chronic obstructive pulmonary disease [COPD]) would be undesirable
* When underfeeding (e.g., renal failure, large wounds) would be especially detrimental
* In patients whose physical or clinical factors promote energy expenditure deviant from normal
* When drugs are used that might alter energy expenditure (e.g., paralytic agents, beta blockers)
* In patients who do not respond as expected to calculated regimens

10. When should enteral nutrition be considered?

Show answer
Always, but especially when a patient is unlikely to meet > 70% of nutritional needs by mouth. Patients who have sustained major head injury (Glasgow Coma Scale score < 8), major torso trauma, major trauma to the pelvis and long bones, or major chest trauma benefit from enteral nutrition. Approximately 85% of postoperative patients (even those undergoing gastrointestinal [GI] surgery) tolerate early enteral feeding (within 24 hours).

11. How do you access the GI tract for feeding?

Show answer
By blind placement of a nasogastric (NG) tube or duodenal placement of a nasoduodenal tube. More distal placement may be achieved endoscopically with a nasojejunal tube (NJ). Gastric decompression and nasojejunal feeds may be accomplished concurrently after endoscopic percutaneous endoscopic gastrostomy or jejunostomy (PEG or PEJ). Alternatively, a gastrostomy or feeding jejunostomy may be placed intraoperatively.

12. What types of enteral formulas are available?

Show answer

Polymeric enteral feedings are soy-based, lactose-free products that contain intact protein, carbohydrates, and fat. Most offer 1 kcal/mL and 37-62 g of protein per liter. Some have additional insoluble or soluble fiber. Special modifications of the standard formulas include “immune-enhancing” agents such as fish oil, arginine, glutamine, and nucleotides. “Elemental” formulas contain amino acids, di-, tri- and quatra-peptides, dextrose, and minimal fat. Several concentrated formulas (2 kcal/mL) are available for use in patients with congestive heart failure (CHF), renal failure, and hepatic failure. In general, products that are disease specific or contain nutrients in elemental form are more expensive than standard products.

13. Are specialized formulas necessary for critically ill patients with diabetes mellitus?

Show answer
No. Formulas with reduced carbohydrates and increased fat loads are marketed as being superior in maintaining glycemic control. These products have not undergone prospective, randomized, controlled trials (PRCTs) to demonstrate superior outcome in ICU patients. The use of standard high-protein formulas in an isocaloric or hypocaloric load combined with appropriate insulin therapy may be the most effective treatment for insulin resistance in stressed type 2 diabetic patients. Glycemic control associated with enhanced outcome is best achieved with insulin, as opposed to carbohydrate restriction. Furthermore, gastric feedings with high-fat formulas in diabetic patients with gastroparesis may be associated with delayed gastric emptying and increased risk of aspiration.

14. Should specialized “pulmonary” formulas be used on all patients on ventilators?

Show answer
No. Specialized high omega-6 fat formulas have been marketed to reduce CO2 production in COPD patients who are CO2 retainers. In theory, these minimize CO2 retention and facilitate weaning. However, avoidance of overfeeding is more beneficial than provision of a high-fat formula.

15. What complications are related to enteral support?

Show answer
Electrolyte abnormalities, hyperglycemia, GI intolerance, pulmonary aspiration, and nasopharyngeal erosions.

16. Should one wait for bowel sounds or flatus before beginning enteral feedings?

Show answer
No.

17. Should one delay nutrition support longer in obese patients, assuming they have increased reserves?

Show answer
No. Obese patients have more fat, but during stress, all patients become hypermetabolic and break down endogenous protein stores to mobilize amino acids for gluconeogenesis, protein production, and energy production. So, even obese individuals “auto-cannabalize.” As with normal-weight patients, obese patients require high-protein nutritional supplementation to meet increased amino acid demands. Theoretically, by providing nutritional support, protein breakdown is minimized.

18. Should enteral formulas be diluted for initial presentation?

Show answer
No. Dilution delays the attainment of feeding goals. Manipulation of the formula increases the likelihood of bacterial contamination. Furthermore, solution osmolarity is a relatively minor culprit in the incidence of diarrhea.

19. How should enteral feeding-related diarrhea be managed?

Show answer
Mild diarrhea usually requires no treatment. Moderate to severe diarrhea may require feeding reduction, antidiarrheal agents, and stool studies for Clostridium difficile. The medication profile should be evaluated for sorbitol-containing elixirs, laxatives, stool softeners, and prokinetic agents. Sanitation issues related to formula handling must be monitored. Some success has been reported with lactobacillus (yogurt) in antibiotic-associated diarrhea or with soluble fiber.

20. Do enteral feedings contain enough water to meet all fluid needs?

Show answer
Most 1-kcal/mL formulas (standard) contain 85% water by volume, and 2-kcal/mL formulas contain 70% water. Water is generally not an issue in ICU patients receiving multiple intravenous (IV) fluids and drugs. However, on the wards or in patients bound for home or postcare facilities, it is essential to write a water prescription with the tube feeding order. General guidelines for the total water needs of patients are shown in Table 8-5.
Thus, if the total calculated need for fluid is 2400 mL for a 60-kg patient and the tube feeding provided 2000 mL of free water, an order should be written to deliver 200 mL of water to the patient twice daily.

Table 8-5. DAILY WATER NEEDS IN RELATION TO AGE

21. How is enteral nutrition infused?

Show answer
Enteral nutrition is generally infused continuously, in bolus form, or cyclically. Continuous infusion is preferred in critically ill patients who require postpyloric feedings. Bolus feedings are generally used in more stable patients with gastric feedings. Cyclic feedings or nocturnal feedings benefit patients who are on concurrent oral intake and in transition to full oral support.

22. Is enteral nutrition better than total parenteral nutrition (TPN)?

Show answer
Yes. Substrates delivered enterally are better tolerated, are associated with fewer metabolic and hepatic complications, and help preserve normal mucosal (”barrier”) integrity. A review of five studies contrasting TPN with no nutrition or early enteral nutrition concluded that TPN is associated with a greater incidence of septic morbidity.

1. Clinical determinants of brain death are the loss of the
   papillary, corneal, oculovestibular, oculocephalic, oropharyngeal, and
   respiratory reflexes for > 6 hours. The patient should also undergo
   an apnea test, in which the pCO₂ is allowed to rise to at
   least 60 mmHg without coexistent hypoxia. The patient should be
   observed for the absence of spontaneous breathing.
2. The estimated risks of HBV, HCV, and HIV transmission by
   blood transfusion in the United States are 1 in 205,000 for HBV, 1 in
   1,935,000 for HCV, and 1 in 2,135,000 for HIV.
3. The most common location of an undescended testicle is the
   inguinal canal.
4. The most common solid renal mass in infancy is a congenital
   mesoblastic nephroma and in childhood a Wilms’ tumor.
5. Ogilvie’s syndrome is acute massive dilatation of the cecum
   and the ascending and transverse colon without organic obstruction.
6. The best screening method for prostate cancer is digital
   rectal exam combined with serum prostate-specific antigen.
7. The most common histologic type of bladder cancer is
   transitional cell carcinoma.
8. Carcinoma in situ of the bladder is treated with
   immunotherapy with intravesical bacillus Calmette-Guérin.
9. Localized renal cell carcinoma is treated with surgery
   (radical nephrectomy).
10. The most common cause of male infertility is varicocele.
11. The most common nonbacterial cause of pneumonia in
    transplant patients is cytomegalovirus.
12. Chimerism is leukocyte sharing between the graft and the
    recipient so that the graft becomes a genetic composite of both the
    donor and the recipient.
13. OKT3 is a mouse monoclonal antibody that binds to and
    blocks the T-cell CD3 receptor.
14. The most common disease requiring liver transplant is
    hepatitis C.
15. Cystic hygroma is a congenital malformation with a
    predilection for the neck. It is a benign lesion that usually presents
    as a soft mass in the lateral neck.
16. In neuroblastomas, age at presentation is the major
    prognostic factor. Children younger than 1 year have an overall
    survival rate > 70%, whereas the survival rate for children older
    than 1 year is < 35%.
17. The most feared complication of diaphragmatic hernia is
    persistent fetal circulation.
18. The three most common variants of tracheoesophageal fistula
    are (1) proximal esophageal atresia with distal tracheoesophageal
    fistula, (2) isolated esophageal atresia, and (3) tracheo-esophageal
    fistula with esophageal atresia.
19. Atresia can occur anywhere in the GI tract: duodenal (50%),
    jejunoileal (45%), or colonic (5%). Duodenal atresia arises from
    failure of recanalization during the 8th-10th week of gestation;
    jejunoileal and colonic atresia are caused by an in utero mesenteric
    vascular accident.
20. The types of aortic dissection are ascending (type A)
    dissection, which involves only the ascending or both the ascending and
    descending aorta, and descending dissection (type B), which involves
    only the descending aorta.
21. A solitary pulmonary nodule is < 3 cm and is discrete on
    chest radiograph. It is usually surrounded by lung parenchyma.
22. Mediastinal staging is indicated in patients with apparent
    or documented lung cancer who have (1) known lung cancer with
    mediastinal nodes > 1 cm accessible by cervical mediastinal
    exploration, as assessed by CT scan; (2) adenocarcinoma of the lung and
    multiple mediastinal lymph nodes < 1 cm; (3) central or large (>

    5 cm) lung cancers with mediastinal lymph nodes < 1 cm; and (4) lung
    cancer with risk of thoracotomy and lung resection.

23. The most common causes of aortic stenosis are now
    congenital anomalies and calcific (degenerative) disease.
24. In mitral regurgitation, the left ventricle ejects blood
    via two routes: (1) antegrade, through the aortic valve, or (2)
    retrograde, through the mitral valve. The amount of each stroke volume
    ejected retrograde into the left atrium is the regurgitant fraction. To
    compensate for the regurgitant fraction, the left ventricle must
    increase its total stroke volume. This ultimately produces volume
    overload of the left ventricle and leads to ventricular dysfunction.
25. The indications for CABG are (1) left main coronary artery
    stenosis; (2) three-vessel coronary artery disease (70% stenosis) with
    depressed left ventricular (LV) function or two-vessel coronary artery
    disease (CAD) with proximal left anterior descending (LAD) involvement;
    and (3) angina despite aggressive medical therapy.
26. Hibernating myocardium is improved by CABG. Myocardial
    hibernation refers to the reversible myocardial contractile function
    associated with a decrease in coronary flow in the setting of preserved
    myocardial viability. Some patients with global systolic dysfunction
    exhibit dramatic improvement in myocardial contractility after CABG.
27. The surgical treatment of ulcerative colitis is total
    colectomy with ileoanal pouch anastomosis.
28. Dieulafoy’s ulcer is a gastric vascular malformation with
    an exposed submucosal artery, usually within 2-5 cm of the
    gastroesophageal junction. It presents with painless hematemesis, often
    massive.
29. The role of blind subtotal colectomy in the management of
    massive lower gastrointestinal bleeding is limited to a small group of
    patients in whom a specific bleeding source cannot be identified. The
    procedure is associated with a 16% mortality rate.
30. Colorectal polyps < 2 cm have a 2% risk of containing
    cancer, 2 cm polyps have a 10% risk, and polyps > 2 cm have a cancer
    risk of 40%. Sixty percent of villous polyps are > 2 cm, and 77% of
    tubular polyps are < 1 cm at the time of discovery.
31. Patients with colorectal cancer with lymph node involvement
    (Dukes’ C) should receive chemotherapy postoperatively to treat
    micrometastases.
32. Goodsall’s rule states the location of the internal opening
    of an anorectal fistula is based on the position of the external
    opening. An external opening posterior to a line drawn transversely
    across the perineum originates from an internal opening in the
    posterior midline. An external opening, anterior to this line,
    originates from the nearest anal crypt in a radial direction.
33. Incarcerated inguinal hernia: structures in the hernia sac
    still have a good blood supply but are stuck in the sac because of
    adhesions or a narrow neck of the hernia sac. Strangulated inguinal
    hernia: hernia structures have a compromised blood supply because of
    anatomic constriction at the neck of the hernia.
34. Chvostek’s sign is spasm of the facial muscles caused by
    tapping the facial nerve trunk. Trousseau’s sign is carpal spasm
    elicited by occlusion of the brachial artery for 3 minutes with a blood
    pressure cuff.
35. The two surgical options for Graves’ disease are subtotal
    thyroidectomy or near-total thyroidectomy.
36. The only biochemical test that is routinely needed to
    identify patients with unsuspected hyperthyroidism is serum
    thyroid-stimulating hormone concentration.
37. The surgically correctable causes of hypertension are
    renovascular hypertension, pheochromocytoma, Cushing’s syndrome,
    primary hyperaldosteronism, coarctation of the aorta, and unilateral
    renal parenchymal disease.
38. The “triple negative test” or “diagnostic triad” for
    diagnosing a palpable breast mass includes physical examination, breast
    imaging, and biopsy.
39. Chest wall radiation is indicated after mastectomy in
    patients with greater than 5 cm primary cancers, positive mastectomy
    margins, or more than four positive lymph nodes, all of which are
    associated with heightened locoregional recurrence rates.
40. Sentinel lymph nodes are the first stop for tumor cells
    metastasizing through lymphatics from the primary tumor.
41. The most common site of origin of subungual melanomas is
    the great toe. Amputation at or proximal to the metatarsal phalangeal
    joint and regional sentinel lymph node biopsy are advised by most
    authors.
42. Ramus marginalis mandibularis, the lowest branch of the
    nerve that innervates the depressor muscles of the lower lip, is the
    most commonly injured facial nerve branch during parotidectomy.
43. Waldeyer’s ring is the mucosa of the posterior oropharynx
    covering a bed of lymphatic tissue that aggregates to form the
    palatine, lingual, pharyngeal, and tubal tonsils. These structures form
    a ring around the pharyngeal wall. This may be the site of primary or
    metastatic tumor.
44. A patient in whom the head and neck examination is
    completely normal but FNA of a cervical node reveals squamous cancer
    should have examination of the mouth, pharynx, larynx, esophagus, and
    tracheobronchial tree under anesthesia (triple endoscopy). If nothing
    is seen, blind biopsy of the nasopharynx, tonsils, base of tongue, and
    pyriform sinuses should be done at the same sitting.
45. The microorganisms implicated in atherosclerosis include Chlamydia
    pneumoniae, Helicobacter pylori, streptococci, and Bacillus
    typhosus.
46. The cumulative 10-year amputation rate for claudication is
    10%.
47. The absolute reduction in risk of stroke is 6% over a
    5-year period in asymptomatic patients with > 60% stenosis who
    undergo carotid endarterectomy plus aspirin versus patients treated
    with aspirin alone (5.1% versus 11%).
48. Abdominal aortic aneurysm’s average expansion rate is 0.4
    cm/year.
49. Heparin binds to antithrombin III, rendering it more
    active.
50. The patient with suspected intermittent claudication should
    initially be evaluated by obtaining ankle brachial index or segmental
    limb pressures at rest.
51. Shock is suboptimal consumption of O₂ and
    excretion of CO₂ at the cellular level.
52. Nitric oxide is synthesized in vascular endothelial cells
    by constitutive nitric oxide synthase and inducible NOS, using arginine
    as the substrate.
53. Saliva has the hightest potassium concentration (20 mEq),
    followed by gastric secretions (10 mEq), then pancreatic and duodenal
    secretions (5 mEq).
54. Basal caloric expenditure = 25 kcal/kg/day with a
    requirement of approximately 1 g protein/kg/day.
55. 6.25 g of protein contains 1 g of nitrogen.
56. Dextrose has 3.4 kcal/g, protein 4 kcal/g, fat 9 kcal/g
    (20% lipid solution delivers 2 kcal/mL).
57. Maximal glucose infusion rates in parenteral formulas
    should not exceed 5 mg/kg/min.
58. Refeeding syndrome occurs in moderately to severely
    malnourished patients (e.g., chronic alcoholism or anorexia nervosa)
    who, upon presentation with a large nutrient load, develop clinically
    significant decreases in serum phosphorus, potassium, calcium, and
    magnesium levels. Hyperglycemia is common secondary to blunted insulin
    secretion. ATP production is mitigated, and the classic presentation is
    respiratory failure.
59. Glutamine is the most common amino acid found in muscle and
    plasma. Levels decrease after surgery and physiologic stress. Glutamine
    serves as a substrate for rapidly replicating cells (interestingly, it
    is also the number one metabolic substrate for neoplastic cells),
    maintains the integrity and function of the intestinal barrier, and
    protects against free radical damage by maintaing GSH levels. Glutamine
    is unstable in IV form unless linked as a dipeptide.
60. Fever is caused by activated macrophages that release
    interleukin-1, tumor necrosis factor, and interferon in response to
    bacteria and endotoxin. The result is a resetting of the hypothalamic
    thermoregulatory center.
61. Cardiac output = heart rate x stroke volume; normal CO is
    5-6 L/min.
62. SVR = [(MAP - CVP)/CO] x 80; normal SVR is 800-1200
    dyne.sec/cm^-5.
63. Hypovolemic shock: low CVP and PCWP, low CO and SVO₂,
    high SVR.
64. Cardiogenic shock: high CVP and PCWP, low CO and SVO₂,
    variable SVR.
65. Septic shock: low or normal CVP and PCWP, high CO
    initially, high SVO₂, low SVR.
66. Kehr’s sign is concurrent LUQ and left shoulder pain,
    indicating diaphragmatic irritation from a ruptured spleen or
    subdiaphragmatic abscess. Anatomically, the diaphragm and the back of
    the left shoulder enjoy parallel innervation.
67. Rebound tenderness implies peritoneal inflammation and
    irritation not simply abdominal tenderness.
68. The 5 Ws of post-operative fever are wound
    (infection), water (UTI), wind (atelectasis,
    pneumonia), walking (thrombophlebitis), and wonder
    drugs (drug fevers).
69. Cricothyroidotomy should not be performed in
    patients < 12 years old or any patient with suspected direct
    laryngeal trauma or tracheal disruption.
70. The radial (wrist) pulse estimates SBP > 80 mmHg;
    femoral (groin) pulse estimates SBP > 70 mmHg; and carotid (neck)
    pulse estimates SBP > 60 mmHg.
71. A general rule for crystalloid infusion to replace blood
    loss is a 3:1 ratio of isotonic crystalloid to blood.
72. Raccoon eyes (periorbital ecchymosis) and Battle’s sign
    (mastoid ecchymosis) are clinical indicators of basilar skull fracture.
73. CPP = MAP – ICP. Some debate exists on the minimum
    allowable CPP, but consensus indicates that a cerebral perfusion
    pressure of 50-70 mmHg is necessary.
74. Violation of the platysma defines a penetrating neck wound.
75. Tension pneumothorax is air accumulation in the pleural
    space eliciting increased intrathoracic pressure and resulting in a
    kinking of the SVC and IVC that compromises venous return to heart.
76. The most common site of thoracic aortic injury in blunt
    trauma is just distal to the take-off of the left subclavian artery.
77. The most common manifestation of blunt myocardial injury is
    arrhythmia.
78. Indications for thoracotomy in a stable patient with
    hemothorax include an immediate tube thoracostomy output of > 1500
    mL and ongoing bleeding of 250 mL/h for 4 consective hours.
79. Beck’s triad is hypotension, distended neck veins, and
    muffled heart sounds.
80. The hepatic artery supplies approximately 30% of blood flow
    to the liver while the portal vein supplies the remaining 70%. The
    oxygen delivery, however, is similar for both at 50%.
81. The Pringle maneuver is a manual occlusion of the
    hepatoduodenal ligament to interrupt blood flow to the liver.
82. Splenectomy significantly decreases IgM levels.
83. 90% of trauma fatalities due to pelvic fractures are due to
    venous bleeding and bone oozing; only 10% of fatal pelvic bleeding from
    blunt trauma is arterial (most common site is superior gluteal artery).
84. Intraperitoneal bladder rupture from blunt trauma:
    operative management; extraperitoneal rupture: observant management.
85. Pseudoaneurysm is a disruption of the arterial wall leading
    to a pulsatile hematoma contained by fibrous connective tissue (but not
    all three arterial wall layers, which defines a true aneurysm).
86. The earliest sign of lower extremity compartment syndrome
    is neurologic in the distribution of the peroneal nerve with numbness
    in the first dorsal webspace and weak dorsiflexion.
87. Posterior knee dislocations are associated with popliteal
    artery injuries and are an indication for angiography.
88. Management of suspected navicular fracture despite negative
    radiography is short-arm cast and repeat x-ray in 2 weeks; at high risk
    for avascular necrosis.
89. Parkland formula: lactated Ringer’s at 4 mL/kg x %TBSA
    (second- and third-degree only) of burn. Infuse 50% of volume in first
    8 hours and the remaining 50% over the subsequent 16 hours.
90. The metabolic rate peaks at 2.5 times the basal metabolic
    rate in severe burns > 50% TBSA.
91. Gallstones and alcohol abuse are the two main causes of
    acute pancreatitis.
92. Alcohol abuse accounts for 75% of cases of chronic
    pancreatitis.
93. Isolated gastric varices and hypersplenism indicate splenic
    vein thrombosis and are an indication for splenectomy.
94. The treatment for gallstone pancreatitis is cholecystectomy
    and intraoperative cholangiogram during the same hospital stay once the
    pancreatitis has subsided.
95. Proton pump inhibitors irreversibly inhibit the parietal
    cell hydrogen ion pump.
96. Definitive treatment of alkaline reflux gastritis after a
    Billroth II includes a Roux-en-Y gastro-jejunostomy from a 40-cm
    efferent jejunal limb.
97. Cushing’s ulcer is a stress ulcer found in critically ill
    patients with central nervous system injury. It is typically single and
    deep, with a tendency to perforate.
98. Curling’s ulcer is a stress ulcer found in critically ill
    patients with burn injuries.
99. Marginal ulcer is an ulcer found near the margin of
    gastroenteric anastomosis, usually on the small bowel side.
100. The most common cause of small bowel obstructions is
     adhesive disease; the second most common cause is hernias.

1. How common is prostate cancer?

Show answer
It is the most common malignancy diagnosed in men in the United States; almost 200,000 new cases were diagnosed in 2001.

2. Do most men die with prostate cancer, rather than from it?

Show answer
Yes, but approximately 31,500 men died of prostate cancer in 2001 in the United States. Thus, it should not be treated as benign.

3. What are the early symptoms of prostate cancer?

Show answer
There are none. By the time significant symptoms develop, the disease is likely to be advanced. This is an argument for screening to detect prostate cancer.

4. What is the best screening method for prostate cancer?

Show answer
Digital rectal examination (DRE) combined with serum prostate-specific antigen (PSA). Since PSA testing was introduced, there has been a stage migration with less metastatic disease and more local-regional disease being detected.

5. How is prostate cancer diagnosed?

Show answer
It is diagnosed with prostate biopsy, which is a biopsy using transrectal ultrasound for guidance. Many cancers are discovered incidentally at transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH).

6. When is prostate biopsy indicated?

Show answer
When either the PSA or DRE result is abnormal.
KEY POINTS: PROSTATE CANCER

1. Prostate cancer is the most common malignancy diagnosed in men in the United States.
2. The best screening method is a combination of digital rectal exam and serum prostate-specific antigen.
3. Clinically localized prostate cancer is treated with surgery, radiation, cryotherapy, or watchful waiting.

7. Does an elevated PSA level mean a man has prostate cancer?

Show answer
No. PSA can be elevated with BPH, prostatitis, or after prostate trauma. It is prostate specific, not prostate cancer specific.

8. What is a free PSA?

Show answer

Free PSA is the percentage of PSA that is not bound to a serum protein carrier. The ratio of free to total PSA is helpful in determining when to do a prostate biopsy. “Free” is good because a higher ratio of free to total PSA is less likely to represent a prostate cancer.

9. Are there any known risk factors for prostate cancer?

Show answer
Yes. African-American men and men with a family history of prostate cancer are at an increased risk. A high-fat diet may play a role in increasing risk of many cancers, including prostate cancer.

10. What is Gleason’s sum?

Show answer
It’s a score that the pathologist gives prostate cancer to estimate its aggressiveness. The two predominant patterns of cancer are scored 1 to 5, and the sum is, therefore, between 2 and 10. Tumors can be well differentiated (2, 3, 4), moderately differentiated (5, 6, 7), or poorly differentiated (8, 9, 10).

11. How is clinically localized prostate cancer treated?

Show answer
Surgery (radical prostatectomy), radiation therapy by external beam or interstitial seed implant, cryotherapy, or watchful waiting.

12. How is advanced metastatic prostate cancer treated?

Show answer
Hormonal ablation therapy (orchiectomy or luteinizing hormone-releasing hormone agonist drugs) or chemotherapy, but these treatments are palliative and not curative.

13. What is the best treatment for prostate cancer?

Show answer
This is highly controversial. Patients must weigh factors such as age, overall health, grade and stage of the disease, and risk of side effects versus complications from the various treatment options.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Catalona WJ: Clinical utility of free and total prostate specific antigen. Rev Prostate 7(suppl):64-69, 1996.
2. D’Amico AV, Whittington R, Malkowicz SB, et al: Biochemical outcome after radical prostatectomy, external beam radiation therapy, or interstitial radiation therapy for clinically localized prostate cancer. JAMA 280:969, 1998.
3. Greenlee RT, Hill-Harmon MB, Murray T, Thun M: Cancer statistics 2001. CA Cancer J Clin 51:15-36, 2001.
4. Keetch DW, Humphrey PA, et al: Clinical and pathological features of hereditary prostate cancer. J Urol 155:1841-1842, 1996. Medline Similar articles Full article
5. Polascik TJ, Pound CR, et al: Comparison of radical prostatectomy and iodine-125 interstitial radiotherapy for the treatment of clinically localized prostate cancer: A 7-year biochemical (PSA) progression analysis. Urology 51:884-890, 1998. Full article
6. Resnick MI, Novick AC: Urology Secrets, 2nd ed. Philadelphia, Hanley & Belfus, 1999.
7. Reiter RE, deKernion JB: Epidemiology, etiology, and prevention of prostate cancer. In Walsh PC, Retik AB, Vaughan ED, et al (eds): Campbell’s Urology, 8th ed. Philadelphia, W.B. Saunders, 2002, pp 3003-3024.

13. Which is preferred: surgical or medical management of descending dissections?

Show answer

* Initial surgical managementApproximately 25% of patients initially treated medically need an operation eventually.
* Operative mortality is much lower today (20%) than in the past.
* Medical management has the same in-hospital mortality (20%).

* Initial medical managementThis avoids unnecessary operation and its attendant cost and complication rate.

14. What is the preferred management of aortic insufficiency in ascending dissections?

Show answer

* Replacement of aortic valveEasy (valved conduits now available)
* Eliminates aortic insufficiency completely
* Should be done in patients with Marfan syndrome

* Repair of aortic valveWith native valve reconstruction, when done correctly, the need to replace the valve at a later time is only 10%.
* Avoids need for anticoagulation, which is necessary when a mechanical valve is used to replace the aortic valve.

15. What is the preferred repair of descending dissections?

Show answer
1. Partial left atrial-to-femoral artery bypass
For:

* Allows unloading of the heart
* Allows distal perfusion to avoid visceral ischemia
* Allows as much time as needed to complete anastomosis

Against: requires heparinization
2. Simple aortic cross-clamping
For: Fast
Against: Placement of the graft has to be done in < 30 minutes or the complication rate, particularly paraplegia, increases significantly.

16. Are there any other alternatives for the treatment of patients with acute aortic dissection?

Show answer
Although in the early stages of development, the use of endovascular stents may prove to be a useful treatment option. The use of these stents is still considered experimental, and the long-term results are not known.

References
WEB SITE
http://www.acssurgery.com
BIBLIOGRAPHY
1. Barron DJ, Livesey SA, Brown IW, et al: Twenty-year follow-up of acute type A dissection: The incidence and extent of distal aortic disease using magnetic resonance imaging. J Card Surg 12:147-159, 1997. Medline Similar articles
2. Cigarroa JE, Isselbacher EM, DeSanctis RW, Eagle KA: Diagnostic imaging in the evaluation of suspected aortic dissection. Old standards and new directions. N Engl J Med 328:35-43, 1993. Medline Similar articles Full article
3. Glower DD, Fann JI, Speier RH, et al: Comparison of medical and surgical therapy for uncomplicated descending aortic dissection. Circulation 82(suppl IV):39-46, 1990.
4. Khan IA, Nair CK: Clinical, diagnostic, and management perspectives of aortic dissestion. Chest 112:311-328, 2002. Full article
5. Nienaber CA, von Kodolitsch Y, Nicolas V, et al: The diagnosis of thoracic aortic dissection by noninvasive imaging procedures. N Engl J Med 328:1-9, 1993. Medline Similar articles Full article
6. Okita Y, Takamoto S, Ando M, et al: Mortality and cerebral outcome in patients who underwent aortic arch operations using deep hypothermic circulatory arrest with retrograde cerebral perfusion: No relation of early death, stroke, and delirium to the duration of circulatory arrest. J Thorac Cardiovasc Surg 115:129-138, 1998. Medline Similar articles
7. Safi HJ, Miller CC, Reardon MJ, et al: Operation for acute and chronic aortic dissection: Recent outcome with regard to neurologic deficit and early death. Ann Thorac Surg 66:402-411, 1998. Medline Similar articles Full article
8. Wheat MW Jr, Palmer RF, Bartley TB, Seelman RC: Treatment of dissecting aneurysms of the aorta without surgery. J Thorac Cardiovasc Surg 50:364-373, 1995.