1. What is hypertonic saline?

Show answer
Normal saline is 0.9% sodium chloride. Hypertonic saline is 7.5% sodium chloride (eight times as concentrated as normal saline).

KEY POINTS: ION CONCENTRATIONS IN CRYSTALLOID SOLUTIONS

1. ½ NS or 0.45% NaCl: 77 mEq of Na+, 77 mEq of Cl-
2. NS or 0.9% NaCl: 154 mEq of Na+, 154 mEq of Cl-
3. Hypertonic NS or 7.5% NaCl: 1283 mEq of Na+, 1283 mEq of Cl-
4. Lactated Ringer’s: 130 mEq of Na+, 110 mEq of Cl-, 38 mEq of lactate, 4 mEq of K+, and 3 mEq Ca+

2. What is hypertonic saline good for?

Show answer
Resuscitation. The initial hypothesis was that a little hypertonic saline would pull extravascular water into the intravascular compartment, rapidly restoring volume. It now appears that an osmotic jolt (even a transient jump from 140 to 180 mOsm) would pacify circulating neutrophils so that they do not stick to the endovasculature and provoke posttraumatic inflammation.

3. Is hypertonic saline good for anything else?

Show answer
Pacification of “primed” neutrophils should decrease the risk of posttraumatic multiple organ failure.

4. How do you convert 1 g of sodium into milliequivalents (mEq)?

Show answer
Divide by the atomic weight of sodium:

1g (1000 mg) of sodium ÷ 23 = 43.5 mEq

5. How many mEq of sodium are in 1 teaspoon of salt?

Show answer
104 mEq (or 2400 mg).

6. How many mEq of sodium are in an 8-oz bottle of Gatorade?

Show answer
5 mEq.

7. How much does a 40-lb block of salt cost?

Show answer
$3.40 at the feed store.

8. What is the electrolyte content of IV fluids?

Show answer
See Table 7-1.

Table 7-1. ELECTROLYTE CONTENT OF INTRAVENOUS FLUIDS

*Lactate is converted immediately to bicarbonate.

9. How do these concentrations relate to body fluid and electrolyte compartments?

Show answer
See Table 7-2.
Table 7-2. ELECTROLYTE CONCENTRATIONS IN BODY FLUIDS

10. What are the daily volumes (mL/24 h) and electrolyte contents (mEq/L) of body secretions for a 70-kg medical student?

Show answer
See Table 7-3.
Table 7-3. DAILY VOLUMES AND ELECTROLYTE CONTENTS OF BODY SECRETIONS

*See question 6.

11. Are sweat glands responsive to aldosterone? Can they be trained?

Show answer
Yes and yes. Archie Bunker’s sweat contains 100 mEq/L sodium, whereas an Olympic marathon runner retains sodium (sweat sodium may be as low as 25 mEq/L).

12. Is Gatorade really just flavored athlete’s sweat?

Show answer
Yes.

13. What are the daily maintenance fluid and electrolyte requirements for a 70-kg medical student?

14. Does the routine postoperative patient require IV sodium or potassium supplementation? Routine serum electrolyte testing?

Show answer
No and no.

15. Can a patient with a good heart and kidneys overcome all but the most woefully incompetent fluid and electrolyte management?

Show answer
Yes.

16. Can one throw a healthy medical student into congestive heart failure by IV infusion of 100 mL of 5% dextrose in saline solution per kg per hour?

Show answer
No. One will simply be ankle-deep in urine.

17. What is subtraction alkalosis?

Show answer
Vigorous nasogastric suction of a patient with a lot of gastric acid eliminates hydrochloric acid, leaving the patient alkaloti

c.
18. Which electrolyte is most useful in repairing a hypokalemic metabolic alkalosis?

Show answer
Chloride.

19. List the best indicators of a patient’s volume status.

Show answer

* Heart rate
* Blood pressure
* Urine output
* Big-toe temperature

20. Does a warm big toe indicate a hemodynamically stable patient?

Show answer
Most likely. The vascular autoregulatory ability of a young healthy patient is huge. The carotid and coronary circulations are maintained until the bitter end. Conversely, if the patient’s big toe is warm and perfused, the patient is stable.

21. What is the minimal adequate postoperative urine output?

Show answer
0.5 mL/kg/h.

22. What is a typical postoperative urine sodium?

Show answer
< 20 mEq/L.

23. Why?

Show answer
Surgical stress prompts mineralocorticoid (aldosterone) secretion so that the normal kidney retains sodium.

24. Explain paradoxical aciduria.

Show answer
Postoperative patients, by virtue of nasogastric suction (loss of gastric acid), blood transfusions (the citrate in blood is converted to bicarbonate), and hyperventilation (decreased Pco2), are typically alkalotic. Patients also are stressed, and their kidneys retain sodium and water. The renal tubules must exchange some other cations for the retained sodium. The kidney chooses to exchange potassium and hydrogen ions. Even in the face of systemic alkalosis, the postoperative kidney absorbs sodium and excretes hydrogen ions, producing a paradoxical aciduria.
KEY POINTS: MECHANISMS OF PARADOXICAL ACIDURIA

1. Nasogastric suction or refractory vomiting results in loss of gastric acid.
2. Physiologic stress promotes renal retention of sodium and water.
3. To hold on to sodium, the kidney must release other cations (potassium and hydrogen).
4. Counterintuitively, the kidney will release hydrogen ions to keep sodium, resulting in acidic urine.

25. What is third spacing?

Show answer
Hypotension and infection prime neutrophils (CD11 and CD18 receptor complexes), promoting adherence to vascular endothelial cells. Subsequent activation of adherent neutrophils spews out proteases and toxic superoxide radicals, blowing big holes in the vascular lining. Water and plasma albumin leak through the holes. The volume pulled out of the vascular space into the third space of the interstitial and hollow viscus (gut) creates relative hypovolemia and requires additional fluid replacement.

26. What is a Lasix sandwich?

Show answer
25% albumin followed by 20 mg of furosemide (Lasix) IV. If the patient is edematous, the IV albumin theoretically sucks water osmotically out of the interstitial third space. As the excessive water enters the vascular compartment, Lasix produces a healthy diuresis. In most intensive care unit patients, however, the infused albumin rapidly equilibrates across the damaged vascular endothelium. No additional water is pulled into the blood volume. Although surgeons often order Lasix sandwiches, they probably work only in healthy patients who do not need them.

References
BIBLIOGRAPHY
1. Brown MD: Evidence-based emergency medicine: Hypertonic versus isotonic crystalloid for fluid resuscitation in critically ill patients. Ann Emerg Med 40:113-114, 2002. Medline Similar articles Full article
2. Bunn F, Roberts I, Tasker R, Akpa E: Hypertonic versus isotonic crystalloid for fluid resuscitation in critically ill patients. Cochrane Database Syst Rev (1):CD002045, 2002. Full article
3. Greaves I, Porter KM, Revell MP: Fluid resuscitation in pre-hospital trauma care: A consensus view. J R Coll Surg Edinb 47:451-457, 2002. Medline Similar articles
4. Traber DL: Fluid resuscitation after hypovolemia. Crit Care Med 30:1922, 2002. Medline Similar articles

1. What are the four principles of medical ethics?

1. Beneficence describes the active role of doing good by intervention.
2. Nonmaleficence is equivalent to saying, “First do no harm.”
3. Autonomy accounts for informed consent, competence, and the patient’s right to refuse treatment and to know what’s going on.
4. Justice means that all patients should receive fair and equal care but that one patient’s care should not squander limited resources for others.

2. What is a do-not-resuscitate (DNR) order?

Show answer
A DNR order instructs the surgeon not to resuscitate the patient if cardiopulmonary arrest occurs; however, a DNR order is much more involved and complicated than the acronym would have you believe. DNR is not absolute.
The Joint Commission for the Accreditation of Healthcare Organizations mandates that hospitals have written guidelines that promote accountability for DNR orders. All DNR orders must be documented in writing, similar to all other orders, in the appropriate section of the patient’s chart. They should specify the treatments to be withheld and treatments that the patient wishes to have implemented. Patients and families must participate in the DNR decision. Moreover, the DNR status should be discussed and reviewed with the other members of the health care team. Finally, a DNR order does not mean that the patient should be medically abandoned.

3. What is the difference between withdrawing and withholding support?

Show answer
A decision to withdraw should not be more problematic than a decision to withhold, because one cannot be sure that an intervention will work until you try it. There is no moral or ethical distinction between withdrawal and withholding of support. Either of the two allows natural progression of disease without the interface of medical technology. The decision to withdraw or withhold support does not equate with patient death, although the probability of death may be greater. After the decision has been made, appropriate management should focus on the patient’s comfort and psychosocial support.

4. What is an advance directive?

Show answer
An advance directive is a method of delineating a competent patient’s wishes for application at a time when he or she is no longer competent. Medical management or the lack thereof can be based on the patient’s wishes rather than a perceived sense of what is best for the patient. Advance directives may be an informal document, such as a living will, or a formal legal document, such as medical durable power of attorney.

5. What is durable power of attorney?

Show answer
A durable power of attorney is a patient-appointed proxy decision maker. The proxy decision maker becomes active as soon as the patient is no longer able to make competent medical decisions. Hence, the durable power of attorney must have been established in advance of the cognitive decline of the patient.

6. What is a living will?

Show answer
A living will, much like a durable power of attorney, is a formal advanced directive in which a competent patient produces a pre-illness guideline for future care in accordance with his or her wishes.

7. What is included in informed consent?

Show answer
Information about the patient’s condition as well as risks and benefits of the recommended treatment are included. Moreover, the operative and nonoperative alternatives (including no treatment) should be discussed with the patient. The patient’s understanding of the information and alternatives should be assessed as part of the informed consent. Finally, informed consent is a voluntary decision made by the patient or on behalf of the patient by a proxy decision maker.

8. What are futile care and medical futility?

Show answer
Ultimately, old age and disease will conquer us all. The definition of medically futile or inappropriate treatment is still debated. Nonetheless, there are four main concepts of medical futility:

1. Health care professionals are not required to provide physiologically futile treatment.
2. Imminent demise argues against treatment if the patient has no likelihood of survival to discharge.
3. Under the concept of lethal condition, medical care is considered futile if the patient will survive temporarily but ultimately expire as a result of the ongoing disease process.
4. Quality of life or qualitative futility argues against treatment if the patient’s quality of life is so poor that it would be unreasonable to prolong life.

Care must be taken, however, in making medical decisions based on futility because these decisions may lead to self-fulfilling prophecies.

9. What are the clinical determinants of brain death?

Show answer
Many of the current concepts of brain death are based on the 1968 report from the ad hoc committee at Harvard Medical School, which called for a new neurologic definition of brain death. But it was not until 1981 that BEMAT justified the neurologic criteria of brain death by stressing the need for intact brainstem integrative function in order for a person to function as a whole. By definition, brain death requires loss of brainstem reflexes in an irreversibly comatose patient. Brain death includes loss of the pupillary, corneal, oculovestibular, oculocephalic, oropharyngeal, and respiratory reflexes for ≥ 6 hours. The patient also should 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. Other ancillary tests are not essential; for example, it is not necessary to perform an intravenous radioisotope cerebral angiogram or a four-vessel contrast cerebral angiogram or to document an isoelectric (”flat”) electroencephalogram.
Of note, all of the above criteria for brain death require the absence of central nervous system depression caused by barbiturates, narcotics, or hypothermia.

10. What is a persistent vegetative state?

Show answer
In a persistent vegetative state, typically seen after improvement of a comatose state, the patient lies motionless and without activity. The patient appears to be awake but does not have awareness of his or her surroundings or higher mental activity. Other names for this entity are coma vigil and akinetic mutism.

11. What is euthanasia?

Show answer
Euthanasia requires that the physician play an active role in assisting in the death of the patient. The concepts of physician-assisted suicide and active and passive euthanasia are highly controversial. In 1992, the Society of Critical Care Medicine published the results of a survey of critical care specialists; 87% had withdrawn life-prolonging support from patients. In addition, the most recent U.S. law pertaining to assisted suicide was passed in Oregon in 1994. This law makes it legal for a physician to prescribe medication to terminally ill patients for the purpose of committing suicide.

12. Who should approach patients’ families about organ donation?

Show answer
Some claim that the physician who has established good rapport with the patient’s family should raise the issue of organ donation. Others believe that the local organ procurement personnel should approach the family because they have greater interest and training in the process. The best approach is probably a combined one.

13. What should patients’ families be told when organ donation is feasible?

Show answer
The surgeon should stress that the patient has died despite an actively beating heart. The family should be questioned about the patient’s wishes regarding organ donation. All topics should be based on the concepts of informed consent. The family should be informed of the likelihood that several patients will benefit from the donated organs. The family needs to understand that there is no guarantee that the organs will be suitable for donation. They should be assured that they are not responsible for the cost of care provided after brain death is determined and that they may refuse organ donation without fear of prejudice.

14. What is the role of the hospital ethics committee?

Show answer
The hospital ethics committee educates hospital staff members, creates policy, and provides a source of consultation.
The function of education is accomplished through grand rounds, seminars, special lectures, and journal clubs. The hospital ethics committee should be viewed as an intrinsic part of the hospital community. Developed policies should be reviewed by other committees and divisions of the hospital to foster a better sense of cohesiveness when ethical and moral dilemmas arise. The consultative function of the ethics committee produces the greatest amount of controversy. In fact, many hospitals negate this function by stating that it interferes with the physician-patient relationship. The hospital ethics committee can and should provide an arena for collaboration and general ethical education within the hospital.

References
BIBLIOGRAPHY
1. Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death: A definition of irreversible coma. JAMA 205:337-340, 1968.
2. Aminoff MJ: The central nervous system. In Medical Diagnosis and Treatment. Norwalk, CT, Appleton & Lange, 1996.
3. Arnold RM, Siminoff LA, Frader JE: Ethical issues in organ procurement: A review for intensivists. Crit Care Med 12:29-48, 1996. Full article
4. Bernat JL, Culver CM, Gert B: On the definition and criterion of death. Ann Intern Med 94:389-394, 1981. Medline Similar articles Full article
5. Harken AH: Enough is enough. Arch Surg 10:1061-1063, 1999. Full article
6. Kelley DF, Hoyt JW: Ethics consultation. Crit Care Med 12:49-70, 1996.
7. McCollough L, Jones J, Brody B: Surgical Ethics. Oxford, Oxford University Press, 1998.
8. Nyman DJ, Eidelman AL, Sprung CL: Euthanasia. Crit Care Clin 12:85-96, 1996. Medline Similar articles
9. Society of Critical Care Ethics Committee: Attitudes of critical care medicine professionals concerning foregoing life-sustaining treatments. Crit Care Med 20:320-326, 1992.
10. State of Oregon: ORS.251.215, The Oregon Death with Dignity Act. Official 1994 Oregon General Election Handbook, 1994, pp 121-124.
11. Younger SJ: Medical futility. Crit Care Clin 12:165-178, 1996.

1. What is urodynamics?

Show answer
Urodynamic studies assess the functional aspects of the storage and emptying ability of the lower urinary tract (LUT). The principles of urodynamic studies originated from hydrodynamics. The components of urodynamic studies are cystometrogram, leak point pressures, urethral profile pressures, pressure-flow studies, uroflowmetry, and electromyography. These studies have evolved into videourodynamics with the addition of fluoroscopy (i.e., video).

2. What is uroflowmetry?

Show answer
Uroflowmetry is the measurement of voided urine (in milliliters) per unit of time (in seconds). The important elements of the test are voided volume (which should be > 150 mL), maximum flow rate (Qmax), and the curve of the flow (which should be bell shaped). The normal Qmax is > 20 mL/sec in men and > 25 mL/sec in women.

3. What is benign prostatic hyperplasia (BPH)?

Show answer
BPH is benign enlargement of the prostate gland that may lead to bladder outlet obstructive symptoms in men. These symptoms have recently been termed lower urinary tract symptoms (LUTS).

4. What is an American Urological Association (AUA) symptom score?

Show answer
It is a self-reported questionnaire developed and popularized by the AUA for the assessment of bothersome LUTS in men. This questionnaire has seven questions with a maximum score of 35. The higher the score, the more severe and bothersome the symptoms. The AUA symptom score has become an index for both the diagnosis and evaluation of treatment outcome in patients with LUTS.

5. What are the main functions of the LUT?

Show answer
Storage and emptying of urine are the main functions. For practical purposes, all symptoms of LUT dysfunction can be categorized into the malfunction of either storing or emptying ability.

6. What are the control mechanisms for LUT function?

Show answer
The control mechanisms for LUT function are recognized as central and peripheral. The central control mechanisms consist of the cortical portion of the frontal lobe of the brain and pontine micturition center. The peripheral control mechanisms include the thoracic sympathetic and lumbar parasympathetic innervation and neuromuscular apparatus of the LUT organs.

7. What is the role of the autonomic nervous system in the function of the LUT?

Show answer
Sympathetic fibers, which originate from the T10-L2 portion of the spinal cord, innervate the bladder neck and proximal urethra. These fibers mostly control the contraction of the proximal urethra or bladder neck and relaxation of the bladder, which results in storage of urine. The parasympathetic fibers, which originate primarily from the S2-S4 portion of the spinal cord, innervate the bladder body. The parasympathetic innervation allows contraction of the bladder smooth muscle, leading to bladder emptying.

8. What is the role of the somatic nervous system in the function of the LUT?

Show answer
Voluntary control of the striated muscle of the external urinary sphincter is controlled by the somatic nervous system. Somatic fibers are conveyed to the sphincter by the pudendal nerve.

9. What is bulbocavernosal reflex?

Show answer
Bulbocavernosal reflex tests the integrity of peripheral neurologic control of the LUT. This reflex is elicited by stimulation of the glans penis in men or the clitoris in women, which causes contraction of the external anal sphincter or bulbocavernosus muscle. Alternatively, the reflex may be stimulated by pulling the balloon of a Foley catheter against the bladder neck. This reflex is present in all normal men and in approximately 70% of normal women. Absence of this reflex in a man is strongly suggestive of a sacral neurologic lesion.

10. What is the most common cause of incontinence in the geriatric population?

Show answer
The most common are transient causes, mostly external, that disrupt the fragile balance of LUT function in elderly patients and cause urinary incontinence. These causes can be recalled with the mnemonic DIAPPERS:

* Delirium
* Infections
* Atrophic urethritis or vaginitis
* Pharmaceuticals
* Psychological (depression)
* Endocrine (hypercalcemia, hyperglycemia)
* Restricted mobility
* Stool impaction

KEY POINTS: URODYNAMICS AND VOIDING FUNCTION

1. Uroflowmetry is the measurement of voided urine (in milliliters) per unit of time (in seconds).
2. Benign prostatic hypertrophy is benign enlargement of the prostate gland that may lead to bladder outlet obstructive symptoms in men.
3. The sacral roots involved in micturition physiology are S2-S4.

11. What is spinal shock? What type of urinary dysfunction does it cause?

Show answer
Spinal shock is the loss of contractility of the smooth muscle below the level of spinal cord injury, leading to difficulty in bladder emptying or urinary retention. This phenomenon may last from hours to several months with a high chance of reversibility if the spinal cord injury is not permanent.

12. What is autonomic dysreflexia? How is it treated?

Show answer
Autonomic dysreflexia results from systematic outpouring of sympathetic discharge, as in patients with spinal cord lesions at or above the T6 level. This dysreflexia is triggered by distention of the bladder or other stimulus of the bowel or LUT. It is manifested by hypertension, bradycardia, hot flush, sweating, and headache. Initial treatment consists of removal of the stimulus, such as emptying the bladder and placing the patient in a sitting position. Nifedipine or nitroprusside may be used as either prophylaxis or treatment of severe episodes. This condition may lead to significant cerebrovascular complication if untreated.

13. What type of bladder dysfunction is seen in diabetic patients?

Show answer
Diabetic cystopathy is manifested primarily as atonic bladder with difficulty in emptying caused by impaired contractility of the bladder or detrusor muscle.

14. What type of bladder dysfunction is seen in patients with multiple sclerosis (MS)?

Show answer
Urgency (83%), urge incontinence (75%), detrusor hyperreflexia (62%), and detrusor sphincter dyssynergia (25%) are among the most common LUT symptoms in patients with MS. Variation in symptoms depends on the site of involvement by MS. Involvement of pontine pathways (tegmentum) is associated with a much higher rate of urinary symptoms.

15. Which sacral roots control the micturition physiology?

Show answer
S2-S4.
16. What are the causes of urinary retention after abdominal or pelvic surgery? Show answer
They are injuries or disruption of pelvic plexus innervation to the LUT.

17. What is Ogilvie’s syndrome?

Show answer
Acute massive dilatation of the cecum and ascending and transverse colon without organic obstruction is known as Ogilvie’s syndrome. This syndrome can be seen in pelvic urologic surgeries, possibly as a result of an imbalance in parasympathetic stimulation of the colon.

18. What is reflex versus psychic erection?

Show answer
Erection after local stimulation is termed reflex erection. The afferent nerves for reflex erection run in the pudendal nerves, and the efferent fibers are found in the S2-S4 parasympathetic outflow. The psychic erection is caused by stimulation of cerebral erotic centers. The afferent stimuli for psychic erection travel through the thoracolumbar sympathetic outflow and sacral parasympathetic fibers.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Bross S, Braun PM, Michel MS, et al: Preoperatively evaluated bladder wall tension as a prognostic parameter for postoperative success after surgery for bladder outlet obstruction. Urol 61:562-566, 2003. Medline Similar articles Full article
2. Holtgrewe HL: Current trends in management of men with lower urinary tract symptoms and benign prostatic hyperplasia. Urology 51(suppl 4A):1-7, 1998.
3. Litwiller SE, Forhman EM, Zimmern PE: Multiple sclerosis and the urologist. J Urol 161:743-757, 1999. Medline Similar articles Full article
4. Mochrer B, Carey M, Wilson D: Laparoscopic colposuspension: A systematic review. Br J Obstet Gynaecol 110:230-235, 2003.
5. Resnick NM, Yalla SV: Geriatric incontinence and voiding dysfunction. In Walsh PC, Retik AB, Vaughan ED, et al (eds): Campbell’s Urology, 7th ed. Philadelphia, W.B. Saunders, 1998.
6. Steers WD, Barrett DM, Wein AJ: Voiding dysfunction, diagnosis, classification and management. In Gillenwater JY, Grayhack JT, Howards SS, Duckett JW (eds): Adult and Pediatric Urology, 3rd ed. St. Louis, Mosby, 1996.
7. Wang CC, Yang SS, Chen YT, Hsieh JH: Videourodynamics identifies the causes of young men with lower urinary tract symptoms and low uroflow. Eur Urol 43:386-390, 2003.

11. Is there any type of stone that cannot be seen on helical CT scan?

Show answer
Patients taking indinavir sulfate (Crixivan) for HIV infection can form stones from the crystals of the medication; these stones are not seen on CT scan.

12. What toxic substance can be produced by using the holmium:YAG laser on uric acid stones?

Show answer
Cyanide is produced from the uric acid. Although this sounds frightening, it is never a problem.

References
WEB SITE
http://www.transplantation-soc.org
BIBLIOGRAPHY
1. Menon M, Resnick M: Urinary lithiasis: Etiology, diagnosis and medical management. In Walsh PC, Retik AB, Vaughan ED, Wein AJ et al (eds): Campbell’s Urology, 8th ed. Philadelphia, W.B. Saunders, 2002, pp 3229-3305.
2. Teichman JM, Vassar GJ, Glickman RD: Holmium: YAG lithotripsy photothermal mechanism converts uric acid calculi to cyanide. J Urol 160:320-324, 1998. Medline Similar articles Full article

References
WEB SITE
http://www.transplantjournal.com
BIBLIOGRAPHY
1. Figlin RA: Renal cell carcinoma: Management of advanced disease. J Urol 161:391, 1999.
2. Greenlee RT, Hill-Harmon MB, Murray T, Thun M: Cancer statistics 2001. CA Cancer J Clin 51:15-36, 2001.
3. Novick AC, Campbell SC: Renal tumors. In Walsh RC, Retik AB, Vaughan ED, et al (eds): Campbell’s Urology, 8th ed. Philadelphia, W.B. Saunders, 2002, pp 2672-2731.
4. Resnick MI, Novick AC: Urology Secrets, 2nd ed. Philadelphia, Hanley & Belfus, 1999.

1. How common is renal cell carcinoma?

Show answer
In the United States, 30,000 new cases of renal cell carcinoma are predicted for 2004 and 2005, about 3% of all adult malignancies.

2. How is kidney cancer detected?

Show answer
The classic triad of hematuria, flank pain, and an abdominal mass is used; however, this triad is found in only about 10% of cases. About 20% of renal cell carcinomas are associated with a paraneoplastic syndrome. Many solid renal tumors are detected incidentally by a computed tomography (CT) scan of the abdomen performed for another reason.

3. Are all solid masses in the kidney renal cell carcinoma?

Show answer
No. Other solid masses include angiomyolipomas, oncocytomas, sarcomas, and metastatic lesions. However, all solid masses should be presumed to be renal cell carcinoma until proven otherwise.

4. What is the unique relationship between renal cell carcinoma and its vasculature?

Show answer
Renal cell carcinoma has a tendency to invade its own venous drainage. Tumor thrombus may extend along the renal vein into the inferior vana cava and even to the right atrium.

5. How should suspected involvement of the vena cava be evaluated?

Show answer
Magnetic resonance imaging or venacavography.

6. How is renal cell carcinoma treated?

Show answer
Surgery is the optimal treatment for localized renal cell carcinoma. The standard operation is a radical nephrectomy, including everything within Gerota’s fascia. Radical nephrectomy can also be performed laparoscopically or with hand-assisted laparoscopic techniques.

7. Does the whole kidney have to be removed in all cases of renal cell carcinoma?

Show answer
No. Nephron-sparing surgery can be performed in cases of bilateral renal cell carcinoma or renal cell carcinoma in a solitary kidney. Because of the risk of postoperative tumor recurrence, nephron-sparing surgery in the presence of a normal contralateral kidney is, at best, controversial.

8. How is metastatic renal cell carcinoma treated?

Show answer
Chemotherapy has been disappointing. The most encouraging results to date are with interleukin-2 (IL-2) treatment; some evidence of definite durable responses has been noted. Research is ongoing using IL-2 with other forms of immune-enhancing strategies. Some forms of adoptive immunotherapy have been encouraging.

KEY POINTS: RENAL CELL CARCINOMA

1. What are the most common types of urinary stones found in North America?

Show answer

* Calcium stones (calcium oxalate, calcium phosphate, or mixed calcium stones): 70%.
* Struvite or magnesium ammonium phosphate stones, often associated with infection: 20%.
* Uric acid stones (radiolucent): 5%
* Cystine stones, often with a genetic association: 5%

2. What are the typical presenting symptoms of a patient with an obstructing stone?

Show answer

* Pain, usually colicky in the flank or radiating to the groin; patients are usually agitated and cannot get in a comfortable position
* Hematuria, gross or microscopic
* Nausea and vomiting caused by obstruction and pressure on the renal capsule

3. What studies are best to diagnose stones?

Show answer

1. Excretory urogram, or intravenous pyelogram (IVP). Ninety percent of stones are radiopaque and can be seen on a plain radiograph of the kidney, ureter, and bladder (KUB). The IVP serves as a functional study to determine the degree of obstruction, level of obstruction, and presence of a contralateral kidney.
2. Currently, rapid-sequence helical computed tomography (CT) scan has gained popularity. Helical CT can accurately identify both renal and ureteral stones. Its advantages include no need for contrast; speed; and ability to identify calcium, uric acid, and cystine stones. Disadvantages include increased cost compared with IVP and inability to distinguish between radiolucent (uric acid) stones and radiopaque (calcium-containing) stones. A KUB should be obtained if the CT has positive results, to distinguish between radiolucent and radiopaque stones.
3. Ultrasound is particularly advantageous in pregnant women.

4. When should a patient with an obstructing stone be admitted to the hospital?

Show answer

* Any sign of infection (e.g., fever, leukocytosis, bacteriuria); infection behind an obstructing stone may result in urosepsis and death
* Intractable vomiting requiring intravenous (IV) fluids
* Pain requiring parenteral analgesics
* Bilateral obstructing stones or obstruction in a solitary kidney

5. What are the treatment options for ureteral calculi?

Show answer

* Wait and watch to see if the stone passes; it usually does. Approximately 90% of stones, 3 mm in size in the distal ureter, will pass. Fifty percent of 5-mm stones will pass, and 20% of stones larger than 6 mm will pass.
* Ureteroscopy and stone basketing or intraureteral lithotripsy (stone blasting) with a laser (holmium, pulsed dye) or electrohydraulic lithotripsy (EHL)
* Extracorporeal lithotripsy (ESWL), or shock waves directed at the stone to break it into small pieces that can then pass spontaneously
* Open ureterolithotomy, now rarely used because of the success of the less invasive techniques listed above

KEY POINTS: URINARY CALCULUS DISEASE

1. The most common stones in patients in the United States are calcium stones.
2. Excretory urogram or intravenous pyelogram, rapid-sequence helical CT, and ultrasound are the imaging studies used to diagnose stones.
3. Steinstrasse is a collection of small calculi that pile up together in the ureter and cause obstruction or symptoms.

6. What are the treatment options for renal calculi?

Show answer

* Expectant management in asymptomatic noninfectious stones
* ESWL
* Ureteropyeloscopy with lithotripsy using a laser. This has become more popular with smaller, flexible, deflectable ureteroscopes, but it is still a challenging procedure for large stones.
* Percutaneous nephrostolithotomy (particularly for stone burden > 2 cm)
* Combination of ESWL and percutaneous nephrostolithotomy
* Open lithotomy (less common because of the success of less invasive treatment options)

7. What is a steinstrasse?

Show answer
Steinstrasse (German for “stone street”) is a collection of small calculi that pile up together in the ureter and cause obstruction or symptoms. This problem may occur after lithotripsy treatment.

8. What is a stent?

Show answer
A stent is a small plastic catheter that coils in the renal pelvis, traverses the ureter, and coils in the bladder. Stents are useful to relieve ureteral obstruction temporarily and possibly facilitate stone passage after the stent is removed. Stents often cause some degree of ureteral dilatation after they have been removed.

9. What is a metabolic evaluation? Who needs one?

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A metabolic evaluation involves examining both serum and 24-hour urine specimens for factors that contribute to stone formation. The goals are to identify an abnormality and to treat it medically to prevent further stone formation. Indications for metabolic evaluation include recurrent stones, multiple stones, bilateral stones, stones in children, and non-calcium-containing stones.

10. Can stones be dissolved?

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* Uric acid stones often can be dissolved by alkalinizing the urine and with hydration therapy.
* Cystine, struvite, and apatite stones sometimes can be dissolved.
* Calcium stones cannot be dissolved.

1. How common a problem is infertility?

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Infertility is the inability to establish a pregnancy during 1 year of well-timed intercourse. This affects 15% of all couples in the United States. In 50% of such couples, the woman is responsible; in 30% of couples, a male factor prevents pregnancy; and in 20% of couples, it is a combination of both.

2. What are the odds that a fertile couple will become pregnant after a single episode of well-timed intercourse?

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During a given ovulatory cycle, 18% of fertile couples become pregnant after well-timed intercourse.

3. What is the best timing for intercourse if a couple is trying to conceive?

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Sperm can survive in the cervical mucus for 48 hours. To achieve pregnancy, therefore, the most effective timing of intercourse is every other day, starting a few days before ovulation.

4. What environmental factors may play a role in male infertility?

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Although reproductive function is relatively durable, various toxins have a negative impact on male fertility. Cigarette smoke and alcohol have been implicated as dose-dependent gonadotoxins, as have recreational drugs, including marijuana, cocaine, and heroin. Radiation (in amounts as low as 200 rads) can influence spermatogenesis, as can chemotherapeutic agents. Calcium channel blockers may interfere with the ability of sperm to fertilize eggs.

5. Can a vasectomy be successfully reversed?

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Yes, but the success rate is affected by the amount of time since the original vasectomy. Among patients who are less than 3 years from vasectomy, the conception rate after reversal is roughly 75%. This success rate declines to about 50% when the reversal is performed 3-8 years after vasectomy and further declines to 30% when 15 or more years have passed.

6. What is in vitro fertilization (IVF)?

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With IVF, eggs are harvested from a woman and combined with sperm in a laboratory setting. The resulting embryos are then transferred to the uterine cavity, where they mature into a fetus. In a specialized version of this technology (i.e., intracytoplasmic sperm injection), an individual sperm is injected into each egg, thus facilitating fertilization and allowing pregnancy even in the presence of small numbers of motile sperm.

7. What is the role of IVF in male infertility?

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Because use of IVF greatly reduces the number of motile sperm needed to generate a pregnancy, it can be quite helpful in men with poor semen quality. The IVF team needs only as many motile sperm as there are oocytes (eggs) to be fertilized.

8. Can sperm obtained directly from the testicle be used to generate a pregnancy?

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For the past several years, it has been recognized that incubation of testicular tissue generally yields small numbers of motile sperm. Through the use of IVF, such sperm can generate pregnancies. Even among men suffering from severe testicular failure, it may be possible to retrieve adequate sperm for use in IVF.

9. What is the role of sperm freezing in the treatment of infertility?

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Sperm can be frozen (cryopreserved) with relative ease. After they are cryopreserved, sperm remain viable for extended periods (years). Cryopreservation can be helpful among men planning to undergo treatment with chemotherapy or radiation therapy.

10. Does wearing boxer shorts versus tight underwear affect male fertility?

Show answer
No.
KEY POINTS: SURGICAL APPROACH TO INFERTILITY

1. Infertility is defined as the inability to establish pregnancy during 1 year of well-timed intercourse.
2. In 50% of infertile couples a female factor prevents pregnancy, in 30% of couples a male factor prevents pregnancy, and in 20% of couples infertility is due to a combination of both female and male factors.
3. The most common cause of male infertility is varicocele.

11. Because normal levels of testosterone are necessary for sperm production, is it helpful to give subfertile men additional testosterone?

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Although decreased levels of testosterone can cause impaired male fertility, giving additional testosterone to men with normal testosterone levels can actually cause a dramatic decline in semen quality. Administration of exogenous testosterone causes the patient to cease production of native testosterone within the testes. The resultant decrease in intratesticular testosterone actually results in a decline in sperm production.

12. What is the most common cause of male infertility?

Show answer
Varicocele, a collection of dilated veins above one or both testes. Among men presenting for treatment of infertility, 40% have a varicocele. Correction of varicocele leads to improvement in semen quality in 70% of patients.

13. If we can clone Dolly (a sheep derived from cloning a fully differentiated mammary cell), can we clone humans?

Show answer
Although for a number of critical ethical reasons cloning technology is not currently used in human reproduction, it theoretically allows the cloning of any individual, creating a genetic duplicate. However, cloning probably will not play a role in the treatment of human infertility.

14. Is IVF associated with an increase in genetic abnormalities?

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This issue is controversial, but probably no. At least one recent publication suggested that infants conceived by either intracytoplasmic sperm injection or IVF have twice the risk of major birth defects compared with naturally conceived infants.

15. Will giving supplemental testosterone improve male fertility?

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No. Exogenous testosterone induces a profound decrease in spermatogenesis and has been explored as a means of male contraception.

16. What is cloning as it pertains to humans?

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Just like Dolly the sheep, human cloning involves nuclear transplantation of the desired clone into an egg devoid of its nucleus. Rather than creating whole human beings, the more controversial ethical dilemma is whether to permit cloning of cells or organs for subsequent transplantation in order to cure human disease.

17. Are undescended testes associated with male infertility?

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Yes. Cryptorchidism is associated with male infertility. The decreased fertility correlates with severely reduced total germ cell counts in prepubertal undescended testes. Bilateral testicular maldescent does decrease semen quality. Interestingly, unilateral cryptorchidism may impair semen quality as well. This suggests that both the abnormally descended testis and its normally positioned counterpart are adversely affected. Surgical repositioning of the testis improves semen quality; the earlier it is done, the better.

References
WEB SITE
http://www.auanet.org
BIBLIOGRAPHY
1. Cortes D, Thorp JM, Visfeldt J: Cryptorchidism: Aspects of fertility and neoplasms. A study of 1,335 consecutive boys who underwent testicular biopsy simultaneously with surgery for cryptorchidism. Horm Res 55:21-27, 2001. Full article
2. Hansen M, Kurinczuk JJ, Bower C, Webb S: The risk of major birth defects after intracytoplasmic sperm injection and in vitro fertilization. N Engl J Med 346:725-730, 2002. Medline Similar articles Full article
3. Hargreave T, Ghosh C: Male fertility disorders. Endocrinol Metab Clin North Am 27:765-782, 1998. Similar articles
4. Ismail MT, Sedor J, Hirsch IH: Are sperm motion parameters influenced by varicocele ligation? Fertil Steril 71:886-890, 1999.
5. Johnson MD: Genetic risks of intracytoplasmic sperm injection in the treatment of male infertility: Recommendations for genetic counseling and screening. Fertil Steril 70:397-411, 1998. Similar articles Full article
6. Kim ED, Winkel E, Orejuela F, et al: Pathological epididymal obstruction unrelated to vasectomy: Results with microsurgical reconstruction. J Urol 160(6 pt 1):2078-2080, 1998.
7. Meriggiola MC, Costantino A, Cerpolini S: Recent advances in hormonal male contraception. Contraception 64:269-272, 2002. Full article
8. Naysmith TE, Blake DA, Harvey VJ, et al: Do men undergoing sterilizing cancer treatments have a fertile future? Hum Reprod 13:3250-3255, 1998.
9. Palermo GD, Schlegel PN, Hariprashad JJ, et al: Fertilization and pregnancy outcome with intracytoplasmic sperm injection for azoospermic men. Hum Reprod 14:741-748, 1999.
10. Pellegrino ED, Kilner JF, Fitzgerald KT, et al: Therapeutic cloning. N Engl J Med 347:1619-1622, 2002. Similar articles Full article
11. Rutkowski SB, Geraghty TJ, Hagen DL, et al: A comprehensive approach to the management of male infertility following spinal cord injury. Spinal Cord 37:508-514, 1999.
12. Scherr D, Goldstein M: Comparison of bilateral versus unilateral varicocelectomy in men with palpable bilateral varicoceles. J Urol 162:85-88, 1999.
13. Wilmut I: Cloning for medicine. Sci Am 279:58-63, 1998. Medline Similar articles

1. What are branchial cleft anomalies?

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Cysts, sinuses, and fistulas that result from incomplete obliteration of the first, second, or third branchial clefts, and are present in early fetal development.

2. Which anomaly is the most common?

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Second branchial cleft anomalies are by far the most common, presenting near the mid- to upper border of the sternocleidomastoid (SCM) muscle. First branchial remnants are less common and third clefts are quite rare. (See Table 88-1.)
Table 88-1. BRANCHIAL CLEFT ANOMALIES

3. How do patients with branchial cleft anomalies present?

Show answer
Those with complete fistulas or sinuses present with intermittent drainage of a mucoid fluid on the neck. Patients with cysts usually present later with a mass (sterile or infected). Complete surgical excision is the treatment of choice.

4. What are the major operative hazards of branchial cleft remnant excision?

Show answer
The second branchial cleft tracts through the bifurcation of the carotid artery. The facial nerve is in close proximity to the first branchial cleft fistula. The superior laryngeal nerve and the recurrent laryngeal nerve are both at risk in dissection of a third branchial cleft.

5. What is a thyroglossal duct cyst?

Show answer
A thyroglossal duct cyst is the most common congenital cyst found in the neck. It is caused by failure of normal obliteration of the migration tract of the thyroid gland. Embryologically, the thyroid descends from the base of the tongue (foramen caecum) to its normal location in the low anterior neck.

6. How do patients with thyroglossal duct cysts present?

Show answer
They present with a paramidline mass in the upper neck; if infected, they may present with fever, tenderness, and erythema.

KEY POINTS: CONGENITAL CYSTS AND SINUSES OF THE NECK

1. The most common brachial cleft anomaly is the second brachial cleft anomaly presenting near the mid- to upper border or the sternocleidomastoid muscle.
2. A thyroglossal duct cyst is the most common congenital cyst found in the neck.
3. A cystic hygroma is a congenital lymphatic malformation that is benign an usually presents as a soft mass in the lateral neck.

7. How are thyroglossal duct cysts treated?

Show answer
The best treatment is complete excision of the cyst, along with the tract. Because embryologically the thyroid descends before formation of the hyoid cartilage, the tract may pass right through the hyoid. Therefore, complete tract removal requires excision of the central portion of the hyoid and dissection up to the base of the tongue (i.e., the Sistrunk procedure).

8. What is a cystic hygroma?

Show answer
A cystic hygroma is a congenital lymphatic malformation with a predilection for the neck. It is a benign lesion that usually presents as a soft mass in the lateral neck. Excision is often challenging because the lymph cysts do not respect the fascial planes and often intertwine with the neurovascular structures in the neck. Near-total excision is the treatment of choice.

References
BIBLIOGRAPHY
1. Alqahtani A, Nguyen LT, Flageole H, et al: 25 years experience with lymphangioma in children. J Pediatr Surg 34:1164-1168, 1999. Medline Similar articles Full article
2. Brown RL, Azizkhan RG: Pediatric head and neck lesions. Pediatr Clin North Am 45:889-905, 1998. Medline Similar articles
3. Kang L, Chang CH, Yu CH, et al: Prenatal detection of cystic hygroma using three-dimensional ultrasound. Ultrasound Med Biol 28:719, 2002. Medline Similar articles
4. Organ GM, Organ CH Jr: Thyroid gland and surgery of the thyroglossal duct: Exercise in applied embryology. World J Surg 24:886-890, 2000.
5. Smith CD: Cysts and sinuses of the neck. In O’Neill JA, Rowe MI, Grosfeld JL, et al (eds): Pediatric Surgery, 5th ed. St. Louis, Mosby, 1998, pp 757-771.
6. Telander RL, Filston HC: Review of head and neck lesions in infancy and childhood. Surg Clin North Am 72:1429-1447, 1992. Medline Similar articles

6. Should patients with hepatoblastoma receive preoperative chemotherapy to shrink the tumors?

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Preoperative chemotherapy does shrink tumors, resulting in easier hepatic resection and lower surgical morbidity. This benefit must be weighed against the considerable toxicity of chemotherapeutic agents.
KEY POINTS: ABDOMINAL TUMORS

1. The most common malignant solid abdominal tumors in children are neuroblastomas, Wilms’ tumor, and hepatoblastomas.
2. In neuroblastomas, age at presentation is the major prognostic factor.
3. Hepatoblastomas usually occur in infants and young children, whereas hepatocellular carcinomas usually occur in children older than 10 years.

References
BIBLIOGRAPHY
1. Caty MG, Shamberger RC: Abdominal tumors in infancy and childhood. Pediatr Clin North Am 40:1253-1271, 1993. Medline Similar articles
2. Herrera JM, Krebs A, Harris P, Barriga F: Childhood tumors. Surg Clin North Am 80:747-760, 2000. Medline Similar articles
3. Reynolds M: Pediatric liver tumors. Semin Surg Oncol 16:159-172, 1999. Medline Similar articles Full article
4. Shamberger RC, Guthrie KA, Ritchey ML, et al: Surgery related factors and local recurrence of Wilms’ tumor in National Wilms’ Tumor Study 4. Ann Surg 229:292-297, 1999. Full article
5. Shimada M: Tumors of the neuroblastoma group. Pathology 2:43-59, 1993.
6. Stocker JT: Hepatic tumors in children. Clin Liver Dis 5:259-281, 2001. Medline Similar articles