McNeil's - surgery Flashcards

Question

With regards to intra-aortic balloon pumps, which of the following is TRUE? A. It consistently decreases inotropic dosages required B. It deflates during early systole C. It maintains a high diastolic pressure D. It increases cardiac preload

Answer 1

C. It maintains a high diastolic pressure Intraaortic balloon pump (IABP) counterpulsation is a very effective means of increasing diastolic coronary blood flow and reducing left ventricular afterload, which act in concert to reduce ischemia. - Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed. As it is inflated with an internal pressure of helium that is greater than intraaortic pressure, it will displace 40ml of blood from the aorta. This added volume causes an increase in aortic pressure and diastolic blood flow (diastolic augmentation). The rapid deflation of the balloon leaves a 40ml void, which effectively decreases aortic pressure and thus left ventricular afterload, during early systole. These beneficial hemodynamic changes – diastolic augmentation and systolic afterload reduction – can greatly increase coronary blood flow and decrease myocardial oxygen consumption. - Critical care handbook of Mass General pg 219 Intra-aortic balloon pumping improves mean blood pressures and coronary artery perfusion and decreases cardiac work and oxygen demand. - Townsend: Sabiston Textbook of Surgery, 18th ed. Insertion of an intra-aortic balloon pump (IABP) for counterpulsation increases diastolic coronary artery perfusion pressure, decreases LV afterload, improves cardiac output, and decreases myocardial oxygen demand. Management of RV infarction consists of early maintenance of RV preload with intravenous fluids, reduction of RV afterload (i.e., afterload-only reducing drugs as for LV dysfunction; consider intra-aortic balloon pump). - Goldman: Cecil Medicine, 23rd ed. balloon deflated prior to and during early left ventricular ejection thus reducing aortic pressure and thus afterload. - http://www.aic.cuhk.edu.hk/web8/IABP.htm

Answer 2

The use of IABP is absolutely contraindicated in the setting of aortic insufficiency and aortic dissection. Relative contraindications for use via a femoral arterial approach relate to the vascular consequences of cannulation—significant aortoiliac or iliofemoral disease, and abdominal or descending thoracic aortic aneurysms. - Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed.

Answer 3

a-Lymphoma

Answer 4

1) Lymphoma All mediastinal masses: Thymoma (20%) > Lymphoma > Teratoma or Thyroid goiter ``` Anterior mediastinum Four Ts Thymoma (45%) “Terrible” lymphoma (20%) Teratoma (15%) Thyroid (or parathyroid) (15%) Also neurogenic or mesenchymal tumors (5%) ``` 4 T's" (Thymoma, Terrible lymphoma, Teratoma, and Thyroid) Middle Mediastinum: - Lymphoma - bronchogenic lung CA ``` Posterior Mediastinum neurogenic tumors (schwannoma, neurofibroma,) ```

Answer 5

B. Tensilon test About 50% of patients with an underlying thymic tumour are asymptomatic, and diagnosis is often incidental. However, the most important factor to elicit is a history of myasthenia gravis or muscle weakness consistent with myasthenia gravis (about 30% of patients with a thymoma have associated myasthenia gravis). Patients with myasthenia gravis may have ocular symptoms only (double vision, drooping eyelids) or generalised muscle weakness, especially facial and oropharyngeal weakness (suggested by difficulty in chewing and swallowing) and/or proximal limb weakness (suggested by difficulty with getting out of chairs or climbing stairs). The diagnosis of MG is based on clinical disease history and typical clinical findings. MG can be confirmed pharmacologically by edrophonium (Tensilon) test which is positive in 90% of MG patients, giving an immediate but transitory improvement of MG signs. A battery of tests can be used in the assessment of the patient with suspected myasthenia gravis, but only a few are available to the emergency clinician. ACh receptor antibody assay is positive in more than 80% of patients with myasthenia but has a turnaround time of several days. Repetitive nerve stimulation and single-fiber electromyography tests are available in the electrophysiology laboratory. Several pharmacologic tests have been used to aid in the diagnosis of suspected myasthenia gravis including parenteral administration of edrophonium chloride (Tensilon), neostigmine, or curare. Edrophonium chloride administration for diagnosis of myasthenia gravis (Tensilon test) is described in detail because of the drug's rapid onset, short duration of action, and widespread acceptance for this diagnostic challenge. - Roberts: Clinical Procedures in Emergency Medicine, 5th ed.

Answer 6

b) spontaneous pneumothorax Clinically stable patients with small pneumothoraces (PTXs) should be observed in the emergency department (ED) for 3–6 hr and discharged home if a repeat chest radiograph excludes progression of the PTX (good consensus). - Roberts: Clinical Procedures in Emergency Medicine, 5th ed.

Answer 7

d) Emergent thoracotomy Indications for emergency thoracotomy are initial chest tube output of 1500 mL of blood or persistent drainage of 200 to 300 mL/hr. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 8

A. Insert chest tube on the right

Answer 9

b. Bacterial pneumonia Infections of the pleural space most commonly follow pneumonia, accounting for 40% to 60% of all empyemas. Thoracotomy is the next most common precursor of empyema, accounting for 20%, and trauma accounts for 4% to 10%. Less commonly, empyema can develop as a result of esophageal rupture and subdiaphragmatic spread. Other uncommon causes include hematogenous seeding of an existing pleural effusion and direct extension from head and neck infections. - Mandell: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed. ``` CAUSES OF EMPYEMA Cause Frequency (%) Pyogenic pneumonia 50 Postsurgical 25 Subphrenic abscess extension 10 Posttraumatic 3–5 Lung abscess rupture 1–3 Generalized sepsis 1–3 Pulmonary tuberculosis 1 Pulmonary mycotic infection 1 Spontaneous pneumothorax ```

Answer 10

Answer: Decortication Phases: Proliferative, Exudative, Fibrino-purulent, Fibrosis

Answer 11

C. Apical Bleb vs. emphysema The question is awkward because it doesn't consider primary vs secondary. But ... it may be easier to answer based on the scenario (young skinny tall guy vs. old smoker) The incidence of secondary spontaneous pneumothorax is similar to that of primary spontaneous pneumothorax. - Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed. Blebs can be found in more than 75% of patients undergoing thoracoscopy for treatment of primary spontaneous pneumothorax. - Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed. The most common condition associated with secondary spontaneous pneumothorax is chronic obstructive pulmonary disease (COPD), which accounts for nearly 70% of cases. - Marx: Rosen's Emergency Medicine, 7th ed. So maybe bleb is the right answer? The answer key says emphysema. Spontaneous pneumothorax is a collection of air or gas in the chest that causes the lung to collapse in the absence of a traumatic injury to the chest or lung. A primary spontaneous pneumothorax usually occurs at rest. Spontaneous pneumothorax is seven times more likely to occur in males than females. Male smokers have 22 times the likelihood of spontaneous pneumothorax compared to non-smoking males. Female smokers have a nine times increase in the likelihood of a spontaneous pneumothorax compared to nonsmoking females. A spontaneous pneumothorax is most likely to occur during the fall or winter months. There are between 800 and 900 cases a year in Canada. Usually, the rupture of a small bleb or bullae (an air- or fluid-filled sac in the lung) causes primary spontaneous pneumothorax. Secondary spontaneous pneumothorax occurs in the setting of known lung disease, most often chronic obstructive pulmonary disease (COPD). Other lung diseases commonly associated with spontaneous pneumothorax include: tuberculosis, pneumonia, asthma, cystic fibrosis, lung cancer and certain forms of interstitial lung disease. If left untreated, recurrence rates of a spontaneous pneumothorax are high. Without treatment same side recurrence rates are as high as 30% at six months and up to 50% at two years. Treatment of spontaneous pneumothorax The objective of treatment is to remove the air from the pleural space, allowing the lung to re-expand. Small pneumothoraces may resolve on their own. Aspiration of air, through a catheter to a vacuum bottle, may re-expand the lung. The placement of a chest tube between the ribs into the pleural space allows the evacuation of air from the pleural space when simple aspiration is not successful or when the pneumothorax is large. Re-expansion of the lung may take several days with the chest tube left in place. Hospitalization is required for chest tube management. Surgery may be recommended for recurrent episodes.

Answer 12

a) Apical bullectomy (via thoracoscopy) We suggest that patients who are clinically stable with a recurrent PSP undergo chest tube insertion followed by VATS Video-assisted thoracoscopic surgery Following a primary spontaneous pneumothorax, a patient is at risk of recurrence particularly in the months immediately after the first episode. Sadikot and associates[13] followed up 153 patients with primary spontaneous pneumothorax for a mean of 54 months and reported that 39% had a recurrent ipsilateral pneumothorax, most within the first year. Once a patient has a primary spontaneous pneumothorax there is also an increased risk of having a pneumothorax on the contralateral side. In the report of Sadikot and coworkers,[13] 15% of their 153 patients developed a pneumothorax on the contralateral side as well. There have been several attempts to predict who will develop recurrent pneumothorax. Patients who are tall and those who continue to smoke are more likely to have a recurrence.[13] Yet, there is no relationship between the number of blebs or the size of the blebs on computed tomography (CT)[14] or the appearance of the lung at thoracotomy[15] and the risk of recurrence. Once a patient has had one recurrence, the risk of another recurrence increases to more than 50%.[16] Most patients with their first primary spontaneous pneumothorax should be managed initially with simple aspiration of the pleural air with a plastic catheter. If this is ineffective, thoracoscopy should be performed promptly, with endo-stapling of blebs and pleural abrasion to create a pleurodesis. Patients with recurrent primary spontaneous pneumothorax should undergo thoracoscopy. When thoracoscopy is unavailable, patients who fail aspiration should be managed with tube thoracostomy with an attempt at pleurodesis with either doxycycline or talc. If, after 3 days of thoracostomy drainage, there is a persistent air leak or the lungs have not re-expanded, thoracotomy should be considered. - Murray & Nadel: Textbook of Respiratory Medicine, 3rd ed. ``` Surgical treatment (usually thoracotomy with abrasion of pleural surfaces) is advocated at the time of the first or second recurrence. [33] [34] Patients who have had one pneumothorax have a 30 to 50% chance of ipsilateral recurrence within 1 to 2 years. [33] After a second spontaneous pneumothorax, the probability of a third rises to 50 to 80%. [33] [35] Surgery may be recommended on the occasion of a patient's first pneumothorax in a number of situations: life-threatening tension pneumothorax, massive air leaks with incomplete reexpansion, an air leak persisting 4 to 5 days after a second intercostal tube has been placed, associated hemothorax with complications, cases of identifiable bullous disease, and failure of easy reexpansion in patients with cystic fibrosis. - Roberts: Clinical Procedures in Emergency Medicine, 3rd ed., Copyright © 1998 ```

Answer 13

The diagnosis of esophageal rupture should always be considered in the differential diagnosis of exudative pleural effusions because, if this condition is not rapidly treated, the mortality increases, with current estimates ranging between 30% and 60%.[294] Approximately 60% of patients with esophageal perforation have a pleural effusion, whereas about 25% have a pneumothorax.[295] The pleural effusion is usually left sided ( Fig. 68.9 ), but it may be right sided or bilateral. - Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed

Answer 14

b) Contrast esophagogram 2016: uptodate says Dx with contrast esophagogram or CT When the diagnosis is considered, a water-soluble contrast agent should be administered. If this study is negative, dilute barium should be administered. Barium is relatively inert, and the fear of barium extravasating into the mediastinum through the site of injury and producing a severe reactive mediastinitis is unfounded. The risk of barium leaking into the mediastinum is far less than that of failing to recognize the perforation in a timely fashion. Also, because barium provides far better mucosal detail than water-soluble agents, only if barium has been used for the esophagogram should this study in search of a perforation be termed negative. - Greenfield Esophagogram is a contrast radio-graph of the esophagus. Gastrografin Contrast Esophagogram is often used to confirm the diagnosis and to locate the position of esophagial perforation.

Answer 15

e? do a esophagogram or CT Nonoperative management should be reserved for clinically stable patients with no evidence of systemic inflammation, expediently diagnosed perforations, and no drainage of any collection into the pleura or peritoneum. A major leakage, or one that occurred through a tumor or an ulcer, requires urgent operation. Limited or absent extravasation on radiographic study allows treatment by intravenous antibiotics and close observation. The esophagus or stomach is perforated during diagnostic upper endoscopy in 0.03% to 0.1% of procedures. [6] [22] [65] Perforation occurs most commonly when the endoscope is passed blindly--namely, in the pharynx or upper esophagus--and the esophagus is perforated more commonly than the stomach. [37] Osteoarthritic spurs on the cervical spine, Zenker's diverticulum, anastomoses, strictures, and weakening of the wall of the esophagus or stomach from inflammation, neoplasm, or ingestion of caustic substances are predisposing factors. Perforation of the midesophagus usually results from biopsy of a carcinoma Endoscopic perforation of the esophagus or stomach may be obvious immediately or within a few hours. Cervical pain, subcutaneous emphysema, fever, tachycardia, and characteristic radiographic appearances make the diagnosis easy, but some distal esophageal injuries are more subtle. [37] An esophagogram should be obtained immediately if perforation is suspected. After ensuring that the patient does not aspirate on swallowing, a water-soluble contrast material should be used for the esophagogram. If the perforation site cannot be identified by this method, a small amount of barium can be used. A major leakage, or one that occurred through a tumor or an ulcer, requires urgent operation. Limited or absent extravasation on radiographic study allows treatment by intravenous antibiotics and close observation. - Feldman: Sleisenger & Fordtran's Gastrointestinal and Liver Disease, 6th ed., Copyright © 1998

Answer 16

a. Zenkers diverticula Not a true diverticulum (unlike meckle’s) True diverticulum of the esophagus at the level of mediastium (due to maliganacy)

Answer 17

a. Barrett’s (adenocarcinoma) Squamous cell carcinomas arise from the squamous mucosa that is native to the esophagus and is found in the upper and middle third of the esophagus 70% of the time. This type of cancer is due to exposure to environmental factors. Smoking and alcohol both increase the risk for foregut cancers by 5-fold. Combined, the risk increases from 25- to 100-fold. Food additives, including nitrosamines found in pickled and smoked foods, long-term ingestion of hot liquids, and vitamin (vitamin A) and mineral deficiencies (zinc and molybdenum) have been implicated. Other disorders that expose the esophagus to mucosal trauma including caustic ingestion, achalasia, bulimia, tylosis (an inherited autosomal dominant trait), Plummer-Vinson syndrome, external-beam radiation, and esophageal diverticula all have known associations with squamous cell cancer. Progressive changes from metaplastic (Barrett's esophagus) to dysplastic cells may lead to the development of esophageal adenocarcinoma. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 18

Prospectively following 100 patients with Barrett's esophagus for 1 year will result in 1 patient developing adenocarcinoma, a rate of 1% per year.[13] This is a similar risk to that of patients with a 20-pack-year smoking history developing lung cancer - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 19

a. B cell leucopenia i don't know what a glyecero is The primary cellular component of chyle is the T lymphocyte. Prolonged loss of chyle results in severe nutritional depletion, water and electrolyte loss, hypolipemia, and lymphopenia of T cells with resulting immunosuppression. - Murray & Nadel: Textbook of Respiratory Medicine, 3rd ed Normal chyle flow ranges between 1.5 and 2.5 L/day but can vary much more widely depending on diet and on the fat content of the diet. During starvation or intravenous feeding, flow falls to about 250 mL/day of clear fluid. Chylothorax is frequently massive (Fig. 16-31) and symptomatic, and significant volume losses can occur through thoracentesis or chest tube drainage. Dehydration, nutritional losses, and a steady decline in circulating lymphocytes can produce significant disability and an increased susceptibility to infection - Schwartz Chap 16

Answer 20

a. Ligate the duct Ligation is 1st option, if you can’t then apply a Drain and start on Medium Chain Fatty Acid Diet to decrease Lymph production, this will slow the output down and may close spontaneously. If not then go back and operate to find and ligate it. For patients with thoracic duct injury and an effusion that persists after 1 week of drainage, video-assisted thoracoscopy or thoracotomy is employed to identify and ligate the thoracic duct above and below the leak. - Townsend: Sabiston Textbook of Surgery, 18th ed. During dissection in the region of the lower jugular vein, the thoracic or lymphatic duct should be carefully ligated if identified. - Cummings: Otolaryngology: Head & Neck Surgery, 4th ed. In a recent review of 823 neck dissections performed by the surgeons at Memorial Hospital in New York City that included the removal of the lymph nodes in level IV, Spiro, Spiro, and Strong[68] found that 14 patients (1.9%) developed a chyle fistula. In this and other studies,[17] a chylous leakage was identified and apparently controlled intraoperatively in the majority of patients who developed the complication. These observations remind the surgeon to not only avoid injury to the thoracic duct proper but also to ligate or clip any visualized or potential lymphatic tributaries in the area of the thoracic duct. - Cummings: Otolaryngology: Head & Neck Surgery, 4th ed.

Answer 21

Answer: - Leave in closed suction drain and start TPN - Thoracostomy tube and TPN nutrition Basically if you're right there staring at the duct that is leaking, ligate it. If it's not intra-op, TPN and drain Total parenteral nutrition allows for control of the fluid and protein loss while avoiding flow of chyle, and in most cases it results in resolution. Management of chyle fistulization in association with neck dissection. - Gregor RT - Otolaryngol Head Neck Surg - 01-Mar-2000; 122(3): 434-9 Always consider conservative management because the thoracic duct leak closes spontaneously in nearly 50% of patients. Few or no symptoms and minimal chyle loss characterize these cases. • Decompress the pleural space with tube thoracostomy or repeated thoracentesis to keep the lung expanded against the chest wall and mediastinum. • Reduce chyle production by instituting total parenteral nutrition or a fat-restricted oral diet supplemented with medium-chain triglycerides.

Answer 22

Answer: chest tube and TPN ******depends on how much per day. If 500ml/day, for 1st week, then surgical intervention is indicated********* If significant chyle drainage (>500 mL/d in an adult, >100 mL/d in an infant) continues despite TPN and good lung expansion, early surgical ligation of the duct is recommended. Treatment of postoperative chylothorax Postoperative chylothorax represents a grave complication with a mortality rate that may approach 50 percent. Management includes chest tube drainage and parenteral nutrition with the patient fasting or orally supplemented with MCT (enter portal vein system directly. Somatostatin and octreotide have been reported to decrease chyle production in postoperative chylothorax and in dog models with surgical transection of the thoracic duct. Duration of conservative therapy: 1) early repair if young and low risk 2) if drain >1L/day, repair day 5-7 3) if malignancy, repair earlier as malvourishment and immunocomprimise 4) post pneumonectomy may not need chest tube Following diagnosis, management of a chylothorax consists initially of tube thoracostomy drainage (chest tube insertion) with complete lung re-expansion and supportive measures, such as a low-fat or fat-free diet supplemented by medium-chain triglycerides and aggressive fluid, electrolyte, and nutritional replacement or correction. Often, these measures are enough to promote closure of the thoracic duct pleural fistula. If the chylothorax is caused by malignancy, primary treatment of the neoplasm may be necessary. Radiation therapy to the mediastinum has been useful in managing chylothorax secondary to lymphoma. Conservative measures for the treatment of chylothorax generally are maintained for 1 to 2 weeks. If the chylous effusion has not responded to this management, surgical intervention is indicated. The most common procedures are ligation of the thoracic duct or mass ligation of tissue at the diaphragmatic hiatus (generally through a right thoracotomy) or direct closure of the duct injury. - Sabiston

Answer 23

none of those 5th ICS, anterior to mid-axillary line - ATLS Guidelines The preferred approach is through the fourth, fifth, or sixth intercostal space in the mid to anterior axillary line. - Townsend: Sabiston Textbook of Surgery, 16th ed.,

Answer 24

A? but you get hypocalcemia in rhabdo. i dunno postrevascularization syndrome, regardless the cause of occlusion (ischemia, trauma, iatrogenic) or the methods used to achieve reperfusion (fibrinolysis, surgery, resuscitative therapy). This "revascularization" syndrome includes several complications, both local (explosive swelling of the limb, compartment syndrome and skeletal muscle infarction (rhabdomyolysis) and general (acidosis, hypercalcemia, hypovolaemic shock, renal, hepatointestinal and pulmonary failures, arrhythmias and cardiac arrest (multiple organ dysfunction). http://www.ncbi.nlm.nih.gov/pubmed/9779243

Answer 25

reperfusion rhabdomyolysis. Better answer would be high-volume IV fluid to diurese Rhabdomyolysis should be suspected in patients with burns, trauma, seizures, alcohol or drug intoxication, prolonged ischemia in muscle groups, and extended coma. The diagnosis can be made by the finding of elevated creatine phosphokinase and a urine microscopy study that shows prominent heme pigment without red blood cells in the urine sediment. ``` Rhabdomyolysis: ACUTE GENERAL Rx - Early, aggressive, high-volume IV fluid replacement with mannitol to induce diuresis to prevent acute renal failure - Treatment of electrolyte imbalances - Alkalinization of urine is controversial but appears helpful in research models LABORATORY TESTS - Screening for myoglobinuria with a simple urine dipstick test using orthotoluidine or benzidine - Blood urea nitrogen, creatinine - Increased CK ( Fig. 1-247 ) - Hyperkalemia - Hypocalcemia - Hyperphosphatemia - Increased urinary myoglobin - Pigmented granular casts - Hyperuricemia Ferri: Ferri's Clinical Advisor 2010, 1st ed ```

Answer 26

Answer: Progression of atherosclerosis Early failure of vein grafts (within 30 days) generally represents a judgmental or technical error within the conduct of surgery. These include simple technical errors, such as a kink or twist within the graft, or failure to completely lyse the valves. Judgmental errors include the use of a small or poor-quality vein conduit or the construction of an anastomosis to an inadequate outflow artery. Intermediate failures (30 days-2 years) are generally caused by intimal hyperplastic lesions that form at anastomotic sites or valve sites within the graft. Late graft failures (beyond 2 years) are most often caused by progression of atherosclerotic occlusive disease within the inflow or outflow vessels. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 27

c. Carotid endarterectomy on the symptomatic side only. I think there is newer evidence but I didn't go looking for it See article. Aymptomatic >60%, Patients should be less than 75 years old with a life expectancy of more than 5 years, and an acceptable risk of surgical complications Symptomatic >50% Not done with 100% b/c it will cause stroke. Generally accepted criteria based on these studies are (1) for symptomatic carotid arteries, more than 50% diameter reduction; and (2) for asymptomatic carotid arteries, more than 80% diameter reduction. Although ACAS recommended surgery for patients with more than 60% stenosis, many clinicians believe the benefit of surgery or angioplasty is not achieved for asymptomatic stenoses less than 80% because of the lower risk for stroke with lesser degrees of carotid stenosis and the relative risk of these interventions. - Townsend: Sabiston Textbook of Surgery, 18th ed. Amaurosis fugax is a painless, monocular loss of vision The benefit of carotid endarterectomy in symptomatic patients with stenosis of 70 percent or greater has been established in three major studies.

Answer 28

(open neck)

Answer 29

a. Leg pulses may be present on examination? This could be neurogenic claudication.. Probably easier to answer with the real stem. And even if it was vascular claudication it could be profunda femoris claudication where you could still technically have pulses distally Treatment - Physical training - Stopping smoking - Pentoxifylline - Nafronyl - Aspirin - Antithrombotics Noninvasive testing may aid in predicting the location and severity of atherosclerotic occlusive disease. Noninvasive evaluation is also helpful to establish a preoperative baseline assessment for subsequent comparison postoperatively. Routine segmental Doppler pressure ABI determinations are the standard studies, but results may be spuriously elevated in diabetic patients and those with renal failure. [Seems to argue against B] - Townsend: Sabiston Textbook of Surgery, 18th ed. Patients should take aspirin 81-325 mg/day, unless there is a contraindication to aspirin therapy such as active gastrointestinal bleeding or a history of allergy to aspirin. - Rakel: Textbook of Family Medicine, 7th ed. Muscle tenderness, an abnormal neuromuscular examination finding, elevated skeletal muscle enzyme levels, and a normal pulse examination finding should distinguish myositis from PAD. - Libby: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed.

Answer 30

Answer: Thromboemolectomy Among patients with stenosis of hemodialysis access grafts, we recommend percutaneous angioplasty rather than surgery as the initial procedure (Grade 1B). Lesions unsuitable for percutaneous transluminal angioplasty can be referred for surgical revision. Once thromboses of an AV graft have developed, the therapeutic options include percutaneous or surgical thrombectomy, thrombolytic agents, and mechanical dissolution. If these modalities are successful, a fistulogram can then be performed and detected stenoses treated with angioplasty or surgical revision. There is no optimal approach to the treatment of a thrombosed graft. The approach varies largely based upon local practice and expertise. Whereas radiocephalic fistulas are preferred when feasible, several reports suggest that when an aggressive approach is undertaken, a high per centage of radiocephalic fistulas either fail to mature or develop thrombosis. - Brenner: Brenner and Rector's The Kidney, 8th ed.

Answer 31

- c. 25% In a large autopsy study, Darling found a 25 percent rupture rate of aneurysms between 4 and 7 cm and a 9.5 percent rupture rate for aneurysms smaller than 4 cm. - Schwartz, Chap 20, P. 941.

Answer 32

b. At a size of 4 cm, they have a 75% chance of rupture.

Answer 33

-USS or CT is necessery pre-op

Answer 34

c. usually mycotic Answer: c. usually mycotic The most common etiology of aneurysms is atherosclerotic degeneration of the arterial wall. The pathogenesis is a multifactorial process involving genetic predisposition, aging, atherosclerosis, inflammation, and localized proteolytic enzyme activation. Most aneurysms occur in elderly people and the prevalence of aneurysms increases with increasing age. Aneurysms can also occur in younger, genetically susceptible individuals with Ehlers-Danlos and Marfan syndromes. Other etiologies include localized infection that results in mycotic aneurysms and the rare tertiary stage of syphilis. The most common location of aortic aneurysms is in the abdominal aorta and up to 40% of patients with infrarenal aneurysms have an aneurysm elsewhere in the aorta. The average age of patients with abdominal aortic aneurysms is 75 years, about 10 years older than the average age of patients with clinically significant arterial occlusive disease. Abdominal aortic aneurysms are more common in men than in women with a male-to-female ratio of approximately 8:1. White males have a higher prevalence than black males or females. In 50- to 75-year-old males, aneurysms over 4 cm occur at a rate of 1.4%; in patients older than 60 years of age, the prevalence of aneurysms greater than 3 cm is 3%. Smoking is the most important risk factor and is associated with 78% of aneurysms discovered on screening. [16] Prevalence of aneurysms is approximately 10% in men with hypertension or with clinical evidence of peripheral, carotid, or coronary arterial disease. There is a definite familial incidence, with a rate of 10 to 20% and an 11.6-fold increase in relative risk in first-degree relatives of patients with abdominal aortic aneurysm. Familial aneurysms affect patients at a younger age and more women are affected. - Sabiston

Answer 35

Answer: Surgery and radiotherapy In almost every instance in which a brain tumor is suspected on the basis of the combined results of history, physical findings, and imaging studies, the first consideration is its surgical resectability. Although small meningiomas or acoustic neuromas usually do not require treatment to reduce intracranial pressure, in the majority of brain tumor patients it is appropriate to start administration of dexamethasone promptly. The purpose is to reduce intracranial pressure, which accompanies the majority of brain tumors, and to relieve neurologic symptoms caused by peritumoral brain edema Although complete excision of a brain tumor is the ultimate goal in every case, this is not always possible. How much surgical success can be achieved with these tumors depends on several factors, including the tumor's proximity to indispensable areas, the skill and experience of the neurosurgeon and the preoperative level of neurologic function. It has already been mentioned that solitary brain metastases are best managed by surgical resection before radiation therapy. Chemotherapy for brain tumors has had a disappointing record. The reasons are many, but inadequacy of drug delivery, tumor cell heterogeneity, and inherent resistance are among the important ones. Almost all efforts have been directed toward the primary brain tumors, especially the gliomas. Established brain metastases, however, respond about as well as systemic metastases do in many cancers, especially breast and small cell lung cancer. - Goldman: Cecil Textbook of Medicine, 21st ed In general, a symptomatic, solitary lesion that is surgically accessible should be removed. Surgery, however, should not be undertaken for multiple lesions or in patients who are severely afflicted by their primary disease. Treatment should also include preoperative dexamethasone, as in any brain or spinal cord tumor, to reduce adjacent brain edema. Whole brain irradiation is almost always indicated. - Schwartz, Chap 26 p.1347

Answer 36

Chordoma Clival chordomas are benign tumors; but because of their critical location, local invasion, recurrence, and occasional metastatic spread, their prognosis is similar to that of malignant tumors. For sacrococcygeal chordomas, the average survival rate from the onset of symptoms is usually 5.7 years. Metastasis is rare, but when it occurs, it is most often to the lymph nodes, lungs, and liver. In 5-40% of patients with spinal and sacrococcygeal chordoma, metastatic lesions have been reported.3 Recurrence after curative resection is frequent and may result in a slow but relentless and fatal progression of the disease as a result of invasion of local pelvic structures. This is one of the most difficult tumors for the surgeon to treat. Infection is a frequent complication. - http://emedicine.medscape.com/article/339169-overview Incidence 1 in 1 000 000 ...

Answer 37

a. Donate all organs with out restriction The pattern of spread of primary CNS neoplasms differs from that of other tumors: even the most highly malignant gliomas rarely metastasize outside of the CNS. The subarachnoid space provides a pathway for spread, so that seeding along the brain and spinal cord can occur in highly anaplastic as well as in well-differentiated neoplasms that extend into the CSF pathways. - Cotran: Robbins Pathologic Basis of Disease, 6th ed., Copyright © 1999 W. B. Saunders Company Patients with primary central nervous system (CNS) tumor have been accepted for organ donation because these tumors very rarely spread outside the CNS. However several case reports of CNS tumor transferral with organ transplantation recently challenged this attitude. Some risk factors for extraneural spread of CNS tumors have been determined, but the absence of risk factors does not exclude the possibility of metastases. To our knowledge, 13 cases of CNS tumor transferral with organ transplantation (one heart, three livers, eight kidneys, one kidney/pancreas) have been reported in the literature. Even if no prospective evaluation of the CNS tumor transmission risk with transplantation has been undergone, this risk may be estimated between a little more than 0% and 3% from retrospective series. The authors consider that patients with CNS tumor should be accepted as donors as long as the risk of dying on the waiting lists is significantly higher than the tumor transferral risk. Therefore the authors would have no restriction for transplanting organs from donors with benign or low-grade CNS tumor. For high-grade tumors, the authors would consider these donors as "marginal donors," and balance the risk of tumor transmission with the medical condition of the recipient. Organ donors with primary central nervous system tumor. - Detry O - Transplantation - 15-Jul-2000; 70(1): 244-8

Answer 38

Neuroblastoma

Answer 39

a. No neurological sequalae In fact, several studies have demonstrated vertebral artery occlusion in approximately 20 percent of nonpenetrating cervical trauma. [0540] [1330] [1370] Fortunately, most of these patients are not symptomatic, which is likely due to a usually generous intracranial and extracranial collateral circulation. In the rare case in which ligation is required for hemostasis, intraoperative angiography may be performed to assess the ability of the patient to tolerate such a procedure. However, in these cases, such studies are probably impractical, and, furthermore, some evidence indicates that sacrifice of one vertebral artery does not lead to permanent neurologic sequelae in most patients. - Browner: Skeletal Trauma, 4th ed. 3% stroke rate (for transected and ligated)

Answer 40

a) meningioma You can shuck out a meningioma like a golf ball. often benign

Answer 41

Answer: meningioma Neuroepithelial tumours account for 50–60 per cent of all primary brain tumours and represent a broad spectrum of neoplasms arising from or sharing morphological properties of neuroepithelial cells. They include glial neoplasms; choroid plexus tumours; tumours with predominant neuronal phenotype (ganglioglioma, dysembryoplastic neuroepithelial tumour and neurocytoma); pineal tumours and embryonal tumours (neuroectodermal tumours, medulloblastoma). Astrocytomas account for approximately 75 per cent of glial tumours. Overall, meningiomas represent the commonest nonglial intracranial neoplasm, accounting for approximately 20 per cent of all primary intracranial tumours. - Adam: Grainger & Allison's Diagnostic Radiology, 5th ed.

Answer 42

c) Fine needle aspirate FNA biopsy has become standard in making both diagnostic and management decisions on neck masses. When the FNA biopsy specimen tests positive for carcinoma and the clinical examination and endoscopy do not reveal a primary tumor site, open excisional biopsy is the next step in confirming or diagnosing the mass. - Cummings: Otolaryngology: Head & Neck Surgery, 4th ed. Needle biopsy with cytologic examination has become the prime diagnostic tool for neck masses. Multiple aspirations with a small-gauge needle is the recommended technique. The exception to this interventional step is the patient who has a pulsatile mass or one who has a palpable thrill or audible bruit associated with the neck mass. - The neck mass. McGuirt WF - Med Clin North Am - 01-Jan-1999; 83(1): 219-34

Answer 43

A. FNA Fine-needle aspiration biopsy of salivary gland neoplasms is a simple and accurate aid in diagnosis. The information gained by cytologic examination can be helpful for patient counseling, preoperative consultation, and surgical planning

Answer 44

B. Urgent thyroidectomy Although lithium doesn't seem to be used much/recommended, the Keyword that makes urgent thyroidectomy the answer is "urgent" - you want to treat the thyrotoxicosis first before going for surgery.. For patients with clinical features of thyroid storm, we begin immediate treatment with a beta blocker (propranolol in a dose to achieve adequate control of heart rate, typically 60 to 80 mg orally every four to six hours), a thionamide, glucocorticoids (hydrocortisone, 100 mg intravenously every eight hours), and cholestyramine (4 g orally four times daily). One hour after a thionamide is given, we administer iodine (SSKI, five drops [20 drops/mL, 38 mg iodide/drop] orally every six hours, or Lugol's solution, 10 drops [20 drops/mL, 8 mg iodine/drop] every eight hours) For patients with life-threatening thyroid storm admitted to an ICU, we suggest propylthiouracil (PTU) (200 mg orally every four hours) rather than methimazole as initial therapy (Grade 2B). PTU blocks T4 to T3 conversion and results in lower serum T3 levels for the first several days of treatment. However, for severe but not life-threatening hyperthyroidism, methimazole (20 mg every six hours) may be preferred because of its longer half life, lower risk of hepatic toxicity, and because it ultimately restores euthyroidism more quickly than PTU. Patients initially treated with PTU should be transitioned to methimazole before discharge from the hospital. For patients with contraindications to thionamides who require urgent correction of hyperthyroidism, surgery is the treatment of choice. Patients who are to undergo surgery require preoperative treatment of thyrotoxicosis. We typically treat with beta blockers (if not contraindicated, propranolol 60 to 80 mg every four to six hours), glucocorticoids to inhibit conversion of T4 to T3 (eg, dexamethasone, 1 to 2 mg every six hours), bile acid sequestrants (eg, cholestyramine 4 g orally four times daily), and, in patients with Graves’ disease, iodine (SSKI, five drops [50 mg iodide/drop] orally every six hours, or Lugol's solution, 10 drops [8 mg iodide/iodine per drop] every eight hours). Lithium has also been given to acutely block the release of thyroid hormone. However, its renal and neurologic toxicity limit its utility.

Answer 45

airway loss due to accidental decannulation or tube obstruction Most life threatening cause (which is rare) tracheo-inomminant fistula.

Answer 46

Answer: Wait until delivery and do thyroidectomy After an appropriate diagnosis, surgical resection remains the primary mode of treatment. The timing of this intervention remains an important decision. A retrospective review suggests equivalent outcomes in patients who undergo thyroidectomy during pregnancy and those who wait until the postpartum state. Radionuclide thyroid ablation is contraindicated during pregnancy. - Goldman: Cecil Medicine, 23rd ed. From Motherrisk Surgery remains treatment of choice for well differentiated thyroid (papillary and follicular) cancer. Due to the relatively indolent course but potential impact on long term survival, therapy during pregnancy can be tailored to the stage of pregnancy. For those presenting in the first trimester, surgery and general anaesthesia can be delayed until the second trimester to reduce the risks associated with surgery to the fetus. A few reports suggested that the risk of fetal loss related to surgery is minimal37.For those patients who present in the later stages of pregnancy with a well-differentiated tumor, surgery can usually be delayed safely until the post partum period

Answer 47

c. Put the patient in trendelenberg position Local pressure is probably a better answer The most commonly injured vascular structure is the internal jugular vein, which is amenable to simple lateral repair or ligation. (Sabiston) If evidence of air embolism then go to trendelenburg and left lateral decubis. Air embolus This is a rare event which can occur following injury to the IJV. Large emboli can produce sudden falls in end-tidal carbon dioxide and arterial blood pressure. A pre-cordial Doppler probe may detect the characteristic murmur of venous embolus. Local pressure should be applied and the anaesthetist informed so the patient can be placed in the Trendelenburg position and rotated to the left. In severe cases attempts can be made to pass a catheter and aspirate air from the right side of the heart. Hyperbaric oxygen therapy, were available, is the ultimate and effective treatment. - Kerawala et al. Prevention of complications in neck dissection. Head & Neck Oncology 2009, 1:35

Answer 48

c. Cardiac complications Severe symptomatic hypothyroidism has been associated with several perioperative complications, including intraoperative hypotension, congestive heart failure, cardiac arrest, and death. Elective surgery should be delayed in patients with severe hypothyroidism until adequate thyroid hormone replacement can be achieved. If emergency surgery is required in such patients, intravenous T3 or T4 and glucocorticoids should be administered perioperatively. Conversely, patients with asymptomatic or mild hypothyroidism generally tolerate surgery well, with only a slight increase in the incidence of intraoperative hypotension; surgery need not be delayed for the month or more required to ensure adequate thyroid hormone replacement.

Answer 49

Facial Nerve Anatomy The facial nerve crosses lateral to the styloid process and penetrates the parotid gland. The nerve lies in a fibrous plane that separates the deep and superficial lobes of the parotid gland. In the lower face, the facial nerve always runs deep to the platysma and SMAS and innervates the muscles on their undersurfaces (except for the buccinator, levator anguli oris, and mentalis muscles) The mandibular (or marginal) division lies along the body of the mandible (80%) or within 1-2 cm below (20%). This is a critical landmark in head and neck surgery. The marginal branch lies deep to the platysma throughout much of its course. It becomes more superficial approximately 2 cm lateral to the corner of the mouth and ends on the undersurface of the muscles. Injury to the marginal branch results in paralysis of the muscles that depress the corner of the mouth. - http://emedicine.medscape.com/article/835286-overview The superficial branches run beneath the skin and above the superficial muscles of the face, which they supply: some are distributed to the Procerus, joining at the medial angle of the orbit with the infratrochlear and nasociliary branches of the ophthalmic. The lower deep branches supply the Buccinator and Orbicularis oris, and join with filaments of the buccinator branch of the mandibular nerve.3 - http://en.wikipedia.org/wiki/Buccal_branch_of_the_facial_nerve

Answer 50

b) left facial nerve - marginal mandibular branch Elevating the corner of the mouth is mostly from: - Zygomatic + Buccal o Zygomaticus major (Elevates corners of mouth) - Buccal o Zygomaticus minor (Elevates upper lip) o Levator labii superioris (Elevates upper lip and midportion nasolabial fold) o Levator labii superioris alaeque nasi (Elevates medial nasolabial fold and nasal ala) o Risorius (Aids smile with lateral pull) o Buccinator (Pulls corner of mouth backward and compresses cheek) o Levator anguli oris (Pulls angles of mouth upward and toward midline) The marginal mandibular innervates the mentalis, which pulls skin of chin upward, as well as depressing the corner and mid lip. - Bailey. Head and Neck : Otolaryngology

Answer 51

The tracheoinnominate fistula may result from prolonged cuff erosion inferiorly and anteriorly to the trachea.

Answer 52

The most common pathogen for post-op parotitis is S. aureus. But neither Vanco nor Clox were options here. First generation cephalosporin is therefore most appropriate. If the diagnosis of parotitis is being entertained, the patient receives IV, high-dose, broad-spectrum antibiotics with good coverage of Staphylococcus (the most common agent cultivated from this disease). - Townsend: Sabiston Textbook of Surgery, 18th ed. Suppurative parotitis, most often caused by Staphylococcus aureus or gram-negative organisms, usually occurs in the postoperative period, in premature newborns, or in debilitated patients with poor oral intake. The gland is warm, hard, and extremely tender; the overlying skin is erythematous. Massage of the parotid expresses purulent drainage from Stensen's duct. - Mandell: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed.

Answer 53

Answer: seroma Unilateral lobectomy virtually never causes permanent hypocalcemia but can cause vocal cord paralysis in as many as 3% of patients. Near-total thyroidectomy causes temporary hypocalcemia in 7 to 10% of patients and permanent hypocalcemia in 0.5 to 1%; temporary vocal cord paralysis occurs in about 1 to 2%. A total extracapsular thyroidectomy may lead to hypoparathyroidism in as many as 30% of individuals, an unacceptable complication rate for patients with indolent malignancy. In addition, vocal cord paralysis is more common after such a procedure. The experience of the surgeon is important in terms of the finer technical points of thyroidectomy, including preservation of the external branch of the recurrent laryngeal nerve, which is important in the fine regulation of voice pitch. This is especially pertinent for individuals who depend on the voice for a livelihood.

Answer 54

This is a dumb question. The pathophysiology of CTS is multifactorial. Increased pressure in the intracarpal canal plays a key role in the development of clinical CTS [4]. While the precise etiology of increased carpal tunnel pressure in CTS is uncertain, experimental evidence suggests that anatomic compression and/or inflammation are possible mechanisms. Increased pressure in the carpal tunnel can injure the nerve directly, impair axonal transport, or compress vessels in the perineurium and cause median nerve ischemia

Answer 55

COPD ``` Uptodate Obesity Female gender Pregnancy Diabetes Rheumatoid arthritis Hypothyroidism Connective tissue diseases Preexisting median mononeuropathy Genetic predisposition Aromatase inhibitor use Workplace factors ```

Answer 56

a) Saline wash, debride and close, then proceed to the OR

Answer 57

??? c) physical exam followed by d) proceed immediately to the OR to remove the dressing and examine the patient under anesthesia

Answer 58

a. Superficial peroneal nerve The surgeon then identifies the crural fascia between the anterior and lateral compartments and divides it along the entire length of the incision, taking care to avoid injury to the lateral peroneal nerve in the superior aspect of the incision, the most common iatrogenic injury during an anterior fasciotomy. - Townsend: Sabiston Textbook of Surgery, 18th ed. Deep peroneal nerve courses anteriorly around fibula, taking a sharp turn as it rounds the fibular neck, to enter anterior compartment of leg. Superficial peroneal nerve supplies lateral compartment of leg, first passing between peroneus longus and passes in a straight line from the common peroneal nerve http://www.wheelessonline.com/ortho/peroneal_nerve Uptodate Neurovascular injury — Injuries to arteries and nerves due to technical issues are specific to the fasciotomy site. In one study, injury to the superficial peroneal nerve occurred in 6 percent of patients undergoing emergent leg fasciotomy for trauma [42]. This injury is generally due to failure to recognize the nerve while extending either the anterior or lateral compartment fascial incision proximally. Superficial peroneal nerve injury is avoided first by knowledge of the normal and variant anatomy (figure 3) of this nerve and stopping the proximal fascial incision of the anterior and lateral compartment 4 to 5 cm distal to the fibular head. (See 'Superficial peroneal nerve' above.) The peroneal artery is at risk for injury with the single-incision technique for lower leg fasciotomy, particularly if a fibulectomy is performed. (See 'Single incision fasciotomy' above.)

Answer 59

b. Redness of the finger Kanavel's signs: know them An infection within the flexor tendon sheath may be the result of the spread of adjacent pulp infections or puncture wounds in the flexor creases. Although the flexor sheath usually is involved, the radial and ulnar bursae may be involved as well. Kanavel considered tenderness over the involved sheath, rigid positioning of the finger in flexion, pain on attempts to hyperextend the fingers, and swelling of the involved part to be the four cardinal signs of suppurative tenosynovitis. Of these, tenderness over the flexor sheath is considered the most significant. - Canale & Beaty: Campbell's Operative Orthopaedics, 11th ed

Answer 60

a) S. Aureus Infectious and Inflammatory Flexor Tenosynovitis The primary inciting event of infectious flexor tenosynovitis (FT) usually is penetrating trauma. Most infections are caused by native skin flora, including both Staphylococcus and Streptococcus species. The most common organism that causes infectious FT is Staphylococcus aureus. - http://emedicine.medscape.com/article/1239040-overview

Answer 61

a. Radial aspect of the dorsum of the wrist a. Radial aspect of the dorsum of the wrist Ganglion cysts can occur at any joint or tendon sheath, but they most often present in the dorsum of the wrist at the scapholunate joint, followed by the volar wrist. They can also occur in the flexor tendon sheaths, and when located at the DIP joints, they are termed mucous cysts2,8 Of the dorsal wrist ganglia, 75% connect with the dorsal scapholunate interosseous ligament.2 Many patients who have had asymptomatic cysts for months or even years can present with newly developed pain or limitation of activity. - http://emedicine.medscape.com/article/1243454-overview Plastic Seminar O Location : • Dorsal wrist (60-70%); Commonly over scapholunate ligament •Volar wrist (18-20%); Between FCR and APL at scaphotrapezoid junction

Answer 62

I think this question is misremembered. Langer's are parallel to muscle I don't think it's genetically predetermined (determined by muscle mvt) They correspond to the natural orientation of collagen fibers in the dermis, and are generally parallel to the orientation of the underlying muscle fibers. Widened scar formation is thought to result from wound edge separation with tension perpendicular to the healing skin wound. A state of tension exists naturally in skin; wounded skin gapes and becomes elliptical rather than round. Although Dupuytren first noted this property of skin, Langer received most of the credit. Langer studied the direction of these ellipses by stabbing a round-tipped awl into hundreds of cadavers. When a wound is closed opposite to the lines of tension, the chance of widened scar formation is increased. - http://emedicine.medscape.com/article/1298541-overview Langer's lines are lines which can be extrapolated by connecting linear openings made when a round pin is driven into the skin of a cadaver, resulting from the principal axis of orientation of the subcutaneous connective tissue (collagen) fibres of the dermis; they vary in direction with the region of the body surface. Skin tends to be much stiffer along these lines rather than across them. These lines were developed by Karl Langer, an anatomy professor, from cadavers in rigor mortis. Kraissl, however, preferred lines oriented perpendicular to the action of the underlying muscles. Later, Borges described relaxed skin tension lines, which follow furrows formed when the skin is relaxed and are produced by pinching the skin. Langer's lines are normal, permanent skin creases. They are clinically significant as incisions made parallel to them heal well and produce less visible scarring. N.B These lines are in the dermis but they are reflected in the skin surface in some sites like : Face , Base of the neck

Answer 63

?immedite closure of skin (skin can cause compartment syndrome if really tight) Removal of necrotic debris is the first step in reducing the bacterial content of the wound. Bacterial counts of greater than 100,000 (105 ) colonies per gram of tissue in pressure ulcers correlate well with impaired wound healing and wound graft failure. Wounds with eschar or large amounts of necrotic debris are best debrided surgically. Fasciotomy is the preferred operative therapy for compartment syndrome involving forearm or leg. Anterior and lateral compartments should be decompressed through an anterior lateral incision, and posterior compartments through a posteromedial incision. These longitudinal incisions are usually left open for delayed primary closure or skin grafting. - Greenfield

Answer 64

E – surgical debridement and myocutaneous flap coverage

Answer 65

b) tissue capsule Complications associated with the use of breast implants can occur in the immediate perioperative period or years later. [3] These complications include exposure, extrusion, or infection of the implants. [1] [57] Careful attention when closing the submuscular pocket and skin can help avoid these problems. Longer-term problems also include asymmetry, capsular contracture, malposition of the implant, rupture, and pain. Capsules of tightly-woven collagen fibers form as an immune response around a foreign body (e.g. breast implants, pacemakers, orthopedic joint prosthetics), tending to wall it off. Capsular contracture occurs when the capsule tightens and squeezes the implant. This contracture is a complication that can be very painful and distort the appearance of the implanted breast. Fibrosis of breast tissue after XRT is common and an increase in capsular contracture rates would be expected. - http://en.wikipedia.org/wiki/Breast_implant

Answer 66

Answer: 12h (debatable) Because irreversible necrotic changes begin in muscle after 6 hours of ischemia without cooling (at 20°C to 25°C), it is preferable to begin the replantation of parts amputated proximal to the palm within this time. With cooling (to 4°C), this time may be extended to 12 hours. For parts with no muscle (digits), the allowable warm ischemia time may be 8 hours or more. With cooling, this has been extended to longer than 30 hours. - Canale & Beaty: Campbell's Operative Orthopaedics, 11th ed. Ischemia time is also an important consideration when evaluating a patient for replantation. For amputated digits, more than 12 hours of warm ischemia is a relative contraindication. Promptly cooling the part to 4°C dramatically alters the ischemia factor, but even ischemia exceeding 24 hours does not necessarily preclude successful digital replantation. Ischemia time is more crucial for replantation above the proximal forearm, and reimplantation is not considered after more than 6 to 10 hours of warm ischemia time. - Townsend: Sabiston Textbook of Surgery, 18th ed. Classical textbook teaching states 6hours warm; 12 with cold Plastic Seminar Contra-indications to replant. Ischemia time - proximal to carpus: > 6hrs warm; >12 hrs cold - digits: > 12 hrs warm; > 24-30 hrs cold

Answer 67

a- thumb Indications for replantation of amputated parts are as follows: 1. Whenever possible for a thumb amputation (it provides >40% of the overall hand function) 2. Single digits that have been amputated distal to the FDS insertion (a manual worker may likely desire revision of amputation and desires to return to work quickly) 3. Multiple digits 4. Most amputations in children, including single digit amputations 5. Guillotine-sharp clean amputations at the hand, wrist, or distal forearm - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 68

b. Muscle In addition, the acceptable ischemia time is shortest with the enteric flaps because of their high tissue oxygen and nutrient demand. - Townsend: Sabiston Textbook of Surgery, 18th ed. Warm ischemic time: muscle, bone, skin Cold ischemic time: muscle, skin, bone I think I disagree with above. I think bone is the most resistant no matter what the temperature is

Answer 69

Answer: bone The time that an amputated part can survive before replantation has not been determined. After 6 hours, additional delay may decrease the success rate of revascularization and lead to diminished function. Skin, bone, tendons, and ligaments tolerate ischemia much better than do muscle and connective tissue. - Roberts: Clinical Procedures in Emergency Medicine, 5th ed. Skin, subcutaneous tissue, muscle, and bone have different ischemic tolerances. Skin and subcutaneous tissue is relatively resistant to anoxia and can tolerate warm ischemia for 4-6 hours and cold ischemia for up to 12 hours.[2, 3] Skeletal muscle is less tolerant to ischemia than skin. Muscle can tolerate warm ischemia for up to 2 hours and irreversible damage to the microcirculation begins at 6 hours, even when under cold ischemia.[4, 5] Bone is more resistant to anoxia and can tolerate up to 24 hours of cold ischemia.

Answer 70

If a problem is suspected, the first response must include removal of enough sutures at the bedside that will relieve pressure on the flap. The standard of care dictates a rapid return to the operating room to release tension, evacuate any fluid collections, eliminate sources of vascular pedicle kinking, and examine and possibly revise the arterial or venous anastomosis. Numerous pharmacologic agents have been used to manipulate vascular tone, the clotting cascade, and to reduce the ill effects of the inflammatory mediators liberated through the arachidonic acid pathway. Leech therapy may on occasion salvage flaps that suffer from significant venous congestion. - Townsend: Sabiston Textbook of Surgery, 18th ed Flap failure shows a biphasic distribution - Failure in the first 12-72 hours is almost exclusively due to technical difficulties at the anastomosis and usually at the venous side - Late failures (>4d) are less common and are primarily related to infection CONSERVATIVE MANAGEMENT SHOULD BE FIRST ATTEMPTED ▪ Reposition patient to ↓ pedicle compression ▪ Remove all dressings ▪ Check for tightness of skin closure, release sutures if necessary ▪ If edema present → elevate involved area, release sutures ▪ Assess hydration status →rule out hypovolemia ▪ Prepare patient for possible surgical re-exploration EMERGENT SURGICAL RE-EXPLORATION IF: ▪ Conservative measures fail after 30-60 min ▪ Definite vascular compromise (artery or vein) ▪ Hematoma is diagnosed TEMPORIZING MEASURES IF DEFINITE VASCULAR PROBLEM, BUT PATIENT CANNOT BE IMMEDIATELY BROUGHT TO THE OPERATING ROOM ▪ Arterial thrombosis: ▫ No substitute for immediate re-exploration ▫ Soft tissue will tolerate 4 h of warm ischemia ▫ Inability to reperfuse flap (no reflow phenomenon) and tissue necrosis occurs after this ▪ Venous thrombosis: ▫ Flap elevated to above level of heart ▫ Leeches

Answer 71

Answer: Alters coagulation cascade (thrombin inhibition) Leech-derived anticoagulants are small molecules that directly inhibit thrombin (factor IIa). Halting the coagulation cascade at this stage prevents fibrinogen cleavage into fibrin, which is necessary for cross-linkage and subsequent clot formation. Hirudin is the actual 65–amino acid anticoagulant protein found in leech salivary glands. - Shannon: Haddad and Winchester's Clinical Management of Poisoning and Drug Overdose, 4th ed. Leech saliva helps reestablish blood flow to reattached body parts by means of a vasodilator, provides a numbing anesthetic (Hirudinae) - No source … suspect Hirudin (direct thrombin inhibitor) • hirudin secreted on biting • direct enzyme inhibitor of thrombin • inhibits conversion of fibrinogen to fibrin other substances secreted as well which act as local anesthetics and vasodilators Hirudin, obtained from the saliva of leeches, is a single-chain polypeptide composed of 65 amino acids, with three disulfide bonds and 8000 to 9000 MW. It is highly specific for thrombin inhibition. Hirudin has a short half-life and is excreted unchanged in the urine. Hirudin has no natural inhibitors, compared with heparin, which has natural inhibitors platelet factor 4 and fibrin II–monomer. As an inhibitor of thrombin, hirudin prevents conversion of fibrinogen to fibrin; thrombin-catalyzed activation of factors V, VIII, and XIII; and importantly, thrombin-induced platelet aggregation. In addition to its small size and high potency for thrombin, hirudin has a dominant antiplatelet effect, even with platelet-rich thrombi. Hirudin has been found to be more effective than heparin in reducing platelet deposition and mural thrombus at similar aPTT levels.115 Levels of aPTT of 2 to 3 control (0.7 to 1 mg/kg hirudin) are effective in limiting arterial thrombosis and platelet deposition. Hirudin prevents thrombus growth at both high and low shear rates of blood flow and has even been found to stop thrombus growth in severe stenoses. - Greenfield

Answer 72

c) Skin color McNeil said something abuot pinprick.. but you won't have any sensory innervation with a free flap Despite numerous techniques, such as Doppler probing and temperature monitoring, clinical assessment remains the gold standard for free flap monitoring. The most common cause of flap failure is venous congestion. - Townsend: Sabiston Textbook of Surgery, 18th ed. After successful flap design and implementation, monitor the flap for viability as early recognition of ischemia is important in preventing subsequent flap necrosis, thus flap failure. Clinical observation is the best method to assess a flap. An extremely pale flap may signify arterial insufficiency, while a blue flap may be secondary to a failure of venous outflow. Two additional tests often used to assess viability are capillary refill and warmth. Assessment of bleeding from the flap after stabbing it with a small needle is believed to be one of the most reliable methods of clinical assessment. In addition to clinical assessment, objective tests such as pH monitoring and transcutaneous oxygen tension (PO2)17,18 can aid in early detection of flap ischemia. Doppler ultrasound is used commonly, and laser Doppler is increasingly useful1 Surface temperature monitoring is another dependable technique. Fluorescein dye and illumination with a Wood lamp is useful; however, it is cumbersome, and adverse reactions to the dye have been reported. - http://emedicine.medscape.com/article/1284569-overview

Answer 73

Answer: allow exudative debris to leave Reduces donor site morbidity decreases potential space that could "lift it off"

Answer 74

better take

Answer 75

a. Better take over contaminated surface In general, full-thickness grafts contract less than do split-thickness grafts. The deep dermal component is able to suppress myofibroblast function by an unknown mechanism. FTSG - more of the characteristics of normal skin, including color, texture, and thickness, - greater collagen content, dermal vascular plexus, and epithelial appendage - less contraction while healing. - limited to relatively small, uncontaminated, well-vascularized wounds and thus do not have as wide a range of applications as split-thickness grafts STSGs -require less ideal conditions for survival and have a much broader range of application -resurface large wounds, line cavities, resurface mucosal deficits, close flap donor sites, and resurface muscle flaps. -disadvantages -more fragile, especially when placed over areas with little underlying soft tissue support, and usually do not withstand subsequent radiation therapy. -They can contract significantly during healing. They tend to be hypo- or hyperpigmented, particularly in darker-skinned individuals. Their thinness, abnormal pigmentation, and frequent lack of smooth texture and hair growth make STSGs more functional than cosmetic.

Answer 76

a – FTSG Depends what contracture it asks for Primary contracture: when you cut it out of the donor site, how much the graft itself bouces and shrinks right then and there- directly proportional to elastin content, so more in FTSG Secondary contracture : how much it contracts once healed/healing - more in STSG ``` FTSG = full thickness skin graft = entire epidermis and dermis PTSG = partial thickness skin graft = epidermis and variable amount of dermis (hair follicles, sweat glands are left behind) ``` A skin graft that includes the entire dermis is called a full-thickness graft, whereas grafts that include only a portion of the dermis are referred to as partial-thickness grafts.. In selecting the type of skin graft to be used, one must consider wound contraction. The thicker the graft, the less wound contraction. A wound that receives no graft but is just left to heal by contraction and reepithelialization will have the greatest amount of wound contraction. Full-thickness skin grafts are usually used in the face to reduce wound contraction. - Sabiston Xenograft (from porcine skin) do not last long and amniotic sack graft rarely used (Swartrz).

Answer 77

a. Secondary contraction is more likely to occur after adequate healing of a split-thickness skin graft than a full-thickness skin graft.

Answer 78

Answer: d. Tendon without its paratenon In the other zones, the flexor tendons are surrounded by loose areolar (paratenon) tissue. Healing those parts devoid of a fibrous sheath is usually excellent because of the good blood supply from the paratenon. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 79

Answer: b. Distal muscle flap pedicled muscle flap (TRAM or LAT flap) After radiation local skin not great--therefore expander or local skin flap won't work. Distal skin flap would be ok but might as well take muscle with it TRAM)

Answer 80

a) bladder Ca Causes of Asymptomatic Gross Hematuria by Incidence 1. Acute Cystitis (23%) 2. Bladder Cancer (17%) 3. Benign Prostatic Hyperplasia (12%) 4. Nephrolithiasis (10%) 5. Benign essential Hematuria (10%) 6. Prostatitis (9%) 7. Renal cancer (6%) 8. Pyelonephritis (4%) 9. Prostate Cancer (3%) 10. Urethral stricture (2%) - http://www.fpnotebook.com/Urology/Lab/GrsHmtr.htm Most patients with hematuria do not have significant pathology, but this depends on the type of hematuria and underlying risk factors. One prospective study found that 61% of patients with hematuria had no finding after evaluation ( Khadra et al, 2000 ). Gross hematuria is usually noticed by the patient and results in an office or emergency room visit. It is a common presenting symptom for patients with bladder or renal cancer ( Yun et al, 2004 ). The sensitivity of gross hematuria for bladder cancer is 83% and the positive predictive value is 22% ( Buntinx and Wauters, 1997 ). However, the studies generating these values were of low quality and based on referral populations. There are no studies available on the likelihood that family medicine patients with this finding will have serious pathology - Rakel: Textbook of Family Medicine, 7th ed.

Answer 81

a) temperature of 38.9 Infection associated with ureteral stones, or obstructed pyelonephritis, is a not uncommon and potentially life-threatening urologic emergency. Such patients are typically febrile and may present with signs of septic shock, such as hypotension. Urgent drainage of the obstructed portion of the urinary tract by either ureteral catheter or percutaneous nephrostomy is essential. A urine culture specimen from the obstructed segment will aid in directing antibiotic therapy. Definitive stone therapy should be delayed until urine cultures are negative and the patient has recovered completely. - Wein: Campbell-Walsh Urology, 9th ed.

Answer 82

B. Deflate the balloon and advance the catheter even further

Answer 83

C. Efferent arteriole constriction and afferent dilation The diuresis is typically a normal physiologic response to the volume expansion and solute accumulation occurring during obstruction. Sodium, urea, and free water are eliminated and the diuresis subsides after solute and fluid homeostasis is achieved. The increased endogenous production and altered regulation of ANP induce a saline diuresis. - Wein: Campbell-Walsh Urology, 9th ed.; The mechanisms involved have been described in detail earlier and involve the combination of intrinsic damage to tubular salt, solute, and water reabsorption, as well as the effects of volume expansion, solute (e.g., urea) accumulation, and attendant increases in natriuretic substances such as ANP. - Brenner: Brenner and Rector's The Kidney, 8th ed Possible mechanisms of post-obstructive diuresis include: - physiological excretion of the previously retained water, salt and urea - impaired sensitivity of collecting duct to ADH - inability to maintain a medullary solute concentration gradient due to increased medullary blood flow during obstruction - increased atrial natriuretic peptide (ANP) levels resulting in natriuresis and diuresis - Glynne, Allen, Pusey. Acute renal failure in practice. 2008

Answer 84

Answer: Percutaneously drain and put patient on tpn A particularly distressing postoperative complication is the development of a pancreatic fistula due to unrecognized intraoperative injury to the pancreas. This is usually manifested in the immediate postoperative period with signs and symptoms of acute pancreatitis and drainage of alkaline fluid from the incision. A CT scan of the abdomen demonstrates fluid collection in the retroperitoneum. Fluid draining from the incision should be analyzed for pH and the presence of amylase. Treatment involves percutaneous or surgical drainage of the fluid collection to avoid the development of a pancreatic pseudocyst or abscess ( Zinner et al, 1974 ; Spirnak et al, 1984). Most fistulas close spontaneously with the establishment of adequate drainage. Because the healing of a pancreatic fistula is usually a slow process, the patient is also supported with hyperalimentation. Surgical closure by excision of the fistulous track and construction of an anastomosis between the pancreas and a Roux-en-Y limb of the jejunum is only occasionally necessary in patients with prolonged drainage. - Wein: Campbell-Walsh Urology, 9th ed.

Answer 85

c.There is a high likelihood that the underlying abnormality which predisposes the patient to this condition is present in both testicles You need to do do a bilateral orchidopexy

Answer 86

b. Examine under anesthesia Diagnosis of testicular torsion is made mainly by clinical suspicion. When uncertain, color Doppler ultrasound or a nuclear testicular scan may help with the diagnosis. In the case of epididymo-orchitis, Doppler ultrasound would demonstrate increased blood flow, and radionuclide can would show increased radionuclide activity. In the case of testicular torsion, however, Doppler would show no blood flow, and radionuclide scan would show poor radionuclide tracer uptake. Immediate surgical exploration is indicated if testicular torsion is suspected. If treated within the first 4 to 6 hours of onset of symptoms, the chance of testicular salvage is high. During surgical exploration, the testicle is rotated to its normal position to restore blood flow to the testicle. If viable, orchiopexy of the affected and the contralateral testicle is completed. If the affected testicle is nonviable, orchiectomy of the affected testicle and orchiopexy of the contralateral side are performed. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 87

b. Epididymo-orchitis Epididymitis is most common in adults, torsion is most common in children

Answer 88

Answer: c. It is most commonly associated with pain and a retracted testicle Although torsion of an undescended testis is rare, it should be considered in any child with abdominal or groin pain and an empty ipsilateral hemiscrotum. - Wein: Campbell-Walsh Urology, 9th ed. Presentation of testicular torsion is acute onset of testicular pain or swelling. Some patients may have episodic symptoms of pain suggestive of intermittent torsion. Physical examination may reveal a tender firm testicle, high riding testicle, horizontal lie of testicle, absent cremasteric reflex, and no pain relief with elevation of the testicle. The spermatic cord may appear thickened. The posteriorly positioned epididymis may be positioned differently. In the case of epididymo-orchitis, Doppler ultrasound would demonstrate increased blood flow, and radionuclide can would show increased radionuclide activity. In the case of testicular torsion, however, Doppler would show no blood flow, and radionuclide scan would show poor radionuclide tracer uptake. - Townsend: Sabiston Textbook of Surgery, 18th ed.

Answer 89

a. observe When the hematoma is discovered early postoperatively, the patient should be returned to the operating room and, under sterile conditions, the wound opened, the hematoma evacuated, the responsible vessel found and ligated, and the wound closed primarily. If hematomas are discovered late, heat should be applied to the wound and the patient managed expectantly with the hope that the hematoma has not become contaminated. If the surgeon suspects the possibility of a postoperative hematoma because of predisposing factors or difficult hemostasis, a closed-suction drain should be used. The catheter should exit through a separate stab incision remote from the primary wound. - Swartz chp 11

Answer 90

Propofol ? (this decreases IOP) Oxybutanine (contraindicated) Propranolol (actually indicated for glaucoma)

Answer 91

Answer given: loss of visual acuity. Maybe loss of papillary light reflex? Patients who have optic neuropathy have decreased visual acuity or visual field defects. A relative afferent pupillary defect – the sine qua non – of an optic neuropathy often is the ocular abnormality evident. If a relative afferent pupillary defect is not evident, the patient does not have a traumatic optic neuropathy, unless it is bilateral. Patients who have bilateral optic nerve dysfunction demonstrate light–near dissociation of their pupillary reactions. The near response is brisker than the pupillary response to light. - Yanoff & Duker: Ophthalmology, 3rd ed. Traumatic Optic Neuropathy: Workup Traumatic optic neuropathy (TON) is based on a clinical diagnosis of optic nerve dysfunction supported by a recent history of trauma to the head. In an acute setting following trauma, the diagnosis may be delayed if the patient is unconscious and a formal visual acuity assessment cannot be performed. In a conscious, cooperative patient, the diagnosis of TON should be verified by testing the patient for an abnormal visual acuity, an ipsilateral afferent pupillary defect (APD), impairment of color vision, and a visual field defect on formal perimetry. - http://emedicine.medscape.com/article/868129-diagnosis

Answer 92

C. Retinal ischemia The most common cause of perioperative retinal arterial occlusion is improper patient positioning resulting in external compression of the eye that produces sufficient intraocular pressure (IOP) to stop flow in the central retinal artery. It is the typical cause of the injury during spine surgery performed with the patient in the prone position - Miller: Miller's Anesthesia, 7th ed.

Answer 93

Answer: surgical exploration Huh? The development of subcutaneous emphysema may cause marked distortion of the patient's appearance, but there is no reason to “treat” the condition, except to take whatever steps are appropriate to stop the air leak. The source of the leak must be found, because some potential causes (esophageal perforation or major bronchial injury) require early intervention.

Answer 94

a. beta hemolytic strep Skin grafts can be placed in the presence of 10^5 or less organisms (except beta-hemolytic strept). - Morell Notes Beta-hemolytic = Groups A-G Despite its devastating effect on skin grafting, infection is the least common cause of graft failure. In addition to the obvious space-occupying effect of infection, a purulent collection actively separates the graft from its bed and destroys the newly formed vessels. The abundant proteolytic enzymes from inflammation and from the microorganisms are responsible for the lysis of the fibrin adhesion and the destruction of vascular connections. The most notable virulent organism that affects skin grafting is group A beta-hemolytic streptococcus (Streptococcus pyogenes), which rapidly destroys the skin graft and literally melts it away. Topical or systemic antibiotics effective against common microorganisms (i.e., staphylococcal, streptococcal, or Pseudomonas organisms) may be helpful in selective situations if administered early on, particularly for patients with diabetes or impaired immunosuppression or after a prolonged intraoperative time. Immunocompetent individuals and do little to guarantee ultimate graft survival in questionable cases. - Roberts: Clinical Procedures in Emergency Medicine, 3rd ed