Surgery Uworld

HIDA scan

nuclear medicine study used to dx gallbladder obstruction. With this technique, a nuclear tracer is injected into the blood and is excreted from the liver into the bile. Typically, the radiotracer can be seen pooling in a normal gallbladder. Failure to visualize tracer in the gallbladder is suggestive of obstruction. If patient already had US showing cholecystitis, scan would not add to the dx. A HIDA scan be used in patients where US cannot make a clear dx of acute cholecystitis

Acute cardiac tamponade

occurs due to a sudden rise in intrapericardial pressure and should be suspected in all adult patients with blunt chest trauma who present with persistent JVD, tachycardia, and hypotension despite aggressive fluid resuscitation. CXR findings typically reveal a normal cardiac silhouette without tension pneumothorax

Cardiac tamponade

Bedside echocardiography can be used to identify a pericardial effusion causing cardiac tamponade. Cardiac tamponade is characterized by Beck's triad: hypotension with pulsus pardoscus, JVD, and muffled heart sounds.

Blunt thoracic trama and bronchial rupture?

Blunt thoracic trauma can cause bronchial rupture with JVD, but this usually is in association with a tension pneumothorax that would be visible on CXR

Blunt thoracic trauma and lung contusion?

Blunt thoracic trauma may cause a lung contusion with varying amounts of blood lost into the pleural space. Ex: hemothorax

Bowel ischemia after procedures on the aortoiliac vessels

Bowel ischemia may complicated up to 7% of procedures on the aortoiliac vessels and most commonly affects the distal left colon. Patients report dull pain over the ischemic bowel as well as hematochezia. Colonoscopy shows a discrete segment of cyanotic and ulcerated bowel.

Deep neck space infections

ALthough deep neck space infections have become less common since the advent of widespread antibiotic use, these infections have a very rapid onset and carry potentially fatal complications, requiring the clinician to be aware of and properly identify such infections. Infection in the retropharygensal space (compared to submandibular space, sublingual space and parapharygneal space) carries the highest risk of spread into the mediastimum, particularly the atnerior and posterior portions of the superior mediastinum as well as to the entire length of the posterior mediastinum. In p atients with an inection in the retropharyengeal space, an abscess can form in the "danger space," which lies between the alar and prevertebral fasciae, and drain by gravity into the posterior mediastinum, resulging in acute necrotizing mediastinitis. Early dx and debridement of the mediastinum is essential in the tx of these severe complication

Chronic processes that cause accumulation of pericardial fluid (as opposed to acute cardiac tamponade)

Chronic processes (such as malignancy or renal failure) cause slow accumulation of pericardial fluid that gradually increases the intrapericardial pressure and allows the pericardial elasticty to adapt slowly. As a result, it may take 1-2 liters of fluid before the intrapericardial pressure reaches a critical point that leads to the same physiologic changes as acute cardiac tamponade. The CXR in these patients tends to show the classic findings of enlarged cardiac silhouette in a globular shape

Tension pneumothorax

Clinical presentation: tracheal deviation to the opposite side; hyper-expanded chest with decreased movement with respiration. Increased percussion note. Elevated central venous pressure (may be decreased in hypovoemic shock). Mgmt: emergency needed thoracostomy in the 2nd intercostal space in the MCL. TP occurs due to the progressive build up of air within the pleural space-->pushes mediastinum to the opposite side; obstructs venous return to the heart-->can rapidly lead to hemodynamic instability, shock and cardiopulmonary arrest. TP should be suspected in trauma patients with respiratory distress, tracheal deviation, hemodynamic collpase, and absent breath sounds with tympatnitic percussion note. Immediate needle thoracstomy should be performed in the 2nd ICS at the MCL

Nerve compression

nerve compression alone may account for paresthesias and numbness in ex, but it would not caue diminshed pulses, coolness to touch, pallor, and severe pain. Ex: patient's numbness can be due to nerve ischemia and not nerve compression

cerebral ischemia

manifest as focal neurologic deficits and pain is NOT typically the major presenting complaint

Febrile nonhemolytic and acute hemolytic transfusion rxns

may cause fever; these rxns typically occur immediately (within 1-6 hours) after the transfusion, not days later

Evalating painet with cervical spine trauma aftera a fall

1st step in the field is to stabilize the cervical spine and spinal column with a backboard, rigid cervical collar, and lateral head supports until a spinal injury is excluded. Next step: assess the airway. Unstable lesions above the third cervical vertebra level can cause immediate paralysis, and lower cervical lesions can damage the phrenic nerve. Cervical spine injuries can be associated with oral maxillofacial trauma, hemorrhage in the retropharygneal space, and significant airway and neck edema; all could prevent adquate landmark visulization during intubation. Patients with cervical spine injuries require initial stabilization of the cervical spine. Orotracheal intubation with rapid-sequence intubation is preferred for establishing an airway in an apneic patient with a cervical spine injury.

DIfferential diagnosis for an anterior mediastinal mass

4 T's: thymoma, teratoma (and other germ cell tumors), thyroid neoplasm, and terrible lymphoma. Seminomas may cause an elevated b-HCG, but the AFP is essentially always normal. Nonseminomatous germ cell tumors often have an elevated AFP, with a considerable number also having an elevated B-HCG.

Postoperative fever

>38C (100.4F) commonly occurs after major surgery and can be due to infectious or noninfectious causes. The timing of POF (eg, immediate, acute, subacute, delayed) is helpful in determining the likely diagnosis. Acute fever occurs within the first week after surgery and is most often caused by nosocominal or surgical site infections or certain noninfectious causes such as PE. Ex: patient with fever and bacteremia, likely related to the indwelling triple-lumen catheter. Coagulase-negative staph (eg strep epidermidis) are a constituent of normal skin flora, and are also the most frequent cause of bloodstream infection in patients with intravascular devices.

Pilondial cysts

Acute pain and swelling of the midline sacrococcygeal skin and subcutaenous tissues is most commonly due to infection of a pilondial cyst. Pilondial cysts are most prevalent in young males, particularly those with larger amounts of body hair. Pilonidal cysts and sinuses beleived to devlop following chronic activing involving the sweating and friction of the skin overlying the coccyx within the superior gluteal cleft. Infection of hair follicles in this region may spread subcutaneously forming an abscess that then ruptures forming a pilondial sinus tract. The chronic sinus tract may then collect hair and debris resulting in recurrent infections and foreign body rxns. When the sinus becomes acutely infected, pain, swelling and purulent discharge occur in the midline postsacral intergluteal region. Tx is by drainage of abscesses and excision of sinus tracts

Pilondial dz

Acute pain and swelling of the midline sacrococcygeal skin and subcutaneous tissues are most commonly due to pilondial dz. The acute presentation involves infection of a dermal sinus tract orignating over the coccyx.

Acute pancreatitis markers

Amylase and lipase are markers for acute pancreatitis. Additional support for the dx includes an elevated WBC, mild azotemia, and hypocalcemia. CT scan can be used to confirm the dx of pancreattis.

Esophageal rupture

An esophageal rupture typically presents with severe retrosternal chest pain and mediastinal free air on CXR and does not cause massive blood loss or cardiac pump failure unresponisve to standard fluid resuscitation

Colonic ischemia and infarction following surgical repair of an abdominal aortic aneurysm

Colonic ischemia follows up to 7% of such procedures due to interference of blood flow to the distal left colon. Common causes include loss of collateral circulation, manipulation of vessels with surgical instruments, prolonged aortic clamping and impaired blood flow through the inferior mesenteric artery. Patients classically present acutely following the procuedure with dull abdominal pain in the area overlying the ischemic bowel and bloody diarrhea. X-rays of colonic ischemia are usually nonspecific except in cases of advance dz. CT scan will show thickening of the bowel wall. Colonoscopy characteristically shows cyanotic mucosa with hemorrhagic ulcerations. There is typically a sharp transition from affected to unaffected mucosa with only a segment of bowel affected by ischemia.

What is the standard tx approach for complicated diverticulitis with abscess formation?

Computed tomography-guided percutaneous drainage. Surgical drainage can be attempted if percutaneous drainage fails.

Ehlers-Danlos and aortic dissection?

Ehlers-Danlos syndrome = connective tissue disease involving collagen that can predispose to aortic dissection. Like Marfan's syndrome, ehlers-danlos syndrome is not the most common cause of aortic dissection and tends to present in younger patients

Acute embolic occlusion

Ex: acute embolic occlusion of the popliteral artery distal to the popliteal fossa but proximal to the branch point for the anterior tibial artery. Arterial occlusion in the lower extremity may arise due to one of 3 major causes: embolus, thrombosis, or trauma. All forms of arterial occlusion will cause pain, diminished pulses, pallor, coolness to touch, neurologic deficits and muscle dysfunction in the affected extremity. In embolic arterial occlusion, the pain classically occurs suddenly and is severe. The pulses tend to be diminished or absent in the affected limb and normal in the unaffected limb. The majority of emboli causing such occlusion originate from the heart either from the ventricles following a MI or from the atria in the setting of atrial fibrillation

Stress fractures

Ex: avid dancer who presents with 2 weeks of right tibial pain consistent with a likely stress fracture, which most commonly occurs in athletes (up to 15% incidence in runners) or nonathletes who suddenly increase their activity. Stress fractures are also common in ballet dancers, basketball and soccer players, and military recruits. The causes of stress fractures are categorized as activity related (eg, excessive training and improper footwear), biomechanical (eg, weak calf muscles, high arched feet, etc), or metabolic (eg demineralized bone from hormonal or nutritional diseases). The fractures occur due to a sudden increase in repeated tension or compression without adequate rest that eventually breaks the bone.

Acute cardiac tamponade presentation

Ex: hypotension (unresponsive to IV fluid bolus), tachycardia, and elevated jugular venous pressure after blunt thoracic trauma consistent with likely acute cardiac tamponade. Cardiac tamponade occurs acutely in trauma bc of bleeding into a stiff pericardium that has no elasticity. Only 100-200 mL of blood is needed to cause a sudden rise in intrapericardial pressure that compresses the cardiac chambers and compromises both venous return (causing elevated JVP) and cardiac output (causing tachycardia and hypotension). The CXR in these patients can appear normal without a change in cardiac silhouette size due to the small amount of pericardial fluid. The resultant cardiogenic shock must be treated immediately with decompression by pericardiocentesis or surgical pericardiotomy to remove this small fluid and reduce the intrapericardial high pressure acutely.

Airway in cervical spine injury

Ex: patient is hypopneic and hypoxic and requries emergency airway excess. He has superficial facial lacerations with a depressed temporal fracture and no signficant neck edema. Orotrahceal intubation with rapid-sequence intubation = preferred way to establish an airway unless there is significant trauma. 4 ppl are required for this procedure: one manually stabilizes the patient, one administers induction anestheisa, one applies cricoid pressure to prevent passive regurgitation until endotracehal tube placement is confirmed, and one places the endotracheal tube. Manual stabilization requries firmly holding either side of the patient's head, with the neck midline and on a firm surface, without applying traction. This prevents neck flexion or rotation during intubation. A difficult intubation kit should be available in case the attempt is unsuccessful

When to suspect diaphragmatic hernia

Ex: patients presents after blunt abdominal trauma with mild respiratory distress and abnormal CXR consistent with diaphragmatic hernia. Blunt abdominal trauma can cause a sudden increase in intraabdominal pressure that overcomes the muscular strength of the diaphragm and leads to large radial tears in the muscle. The resultant diaphragmatic rupture allows leakage of intraabdominal contents into the chest, causing compression of the lungs and mediastinal deviation

Prosthetic joint infections

Ex: subacute, worsening pain in prosthetic knee 6 months after knee replacement surgery. SYnoval fluid analysis shows an elevated WBC count with a predomonnace of neutrophils, which are highly suggestive of an inflammatory process, most likely a prosthetic joint infection. This px and the relative long period btwn the arthroplawsty and presentation favor coag-negative Staphyloccus, including Dstaph epidermidisd, as the most likely pathogen. Infection with Staphylococcus epidermis should be considered in patients who have a subacute presentation of delayed-onset prosthetic joint infection. Removal of the infected prosthesis is usually required. Pseudomonas aeruginosa and S auerus cause early-onset prosthetic joint infection. A subacute presentation several months after the initial arthroplasty would be uncommon with these organisms. Neisseria gonorrhoae can cause septic arthritis in assocition with disseminated gonoccal disease; migraotry polyarthritis, tenosynovitis, and rash are usually present. Chylmaida trachomatis and Salmonella species can be associted with reactive arthrtis following an inital GU or GI infection; the classic px: arthritis with urethritis/enteritis and conjunctivitis. Borrelial burgdoferia is the organisms that causes Lyme dz. Although chronic Lyme dz can present wtih arthritis, S epidermidis is a more frequent cause of prosthetic joint infection.

Fenofibrate

Fenofibrate, in addition to obestiy, can contribute to gallstone formation.

Febrile nonhemolytic transfusion rxn (most common immunologic blood transfusion rxns)

Fever and chills. Within 1-6 hours of transfusion. Caused by cytokine accumulation during blood storage.

Acute hemolytic transfusion rxn

Fever, flank pain, hemoglobinuria, renal failure and DIC. Within 1 hour of transfusion. Positive direct Coombs test, pink plasma. Caused by ABO incompatibility.

Clinical manifestations of basilar skull fractures

Hematoma of the mastoid process or periauricular hematomas (Battle's sign). Bilateral peri-orbital hematomas (raccoon eyes). Hemotympanum. Cerebrospinal fluid otorrhea, CN palsies (resulting in anosmia, vertigo, tinnitus, or hearing loss).

Suppurative hidraednitis

Hidradentitis suppurative, pilonidal dz, dissecting folliculitis of the scalp and acne conglobata tare members of the follicular occlusion tetrad. Affected patients present with multiple painful nodules and pustules of the axillae and growin. These lesions lead to sinus formation and fibrosis

Ruptured abdominal aneruysm

Hypotension and abdominal pain. CT scan: ruptured aorta with blood collection in the adventitial layer (enlarged cardiac silhouette). An abdominal aortic aneruysm can rupture freely into the peritoneal cavity or into the retroperitoneum. These ruptures are associated with significant abdominal pain and hypotension. Patients with a ruptured aortic aneurysm require urgent surgery. If the patient is unstable and rupture has been diagnosed, no further eval is required and the pt is tranferred straight to the OR. CT scanning is only done in stable patietns. In patients not stable enough to undergo CT scan, the presence of an aneruysm can be confirmed at the bedside by ultrasound. Surgical repair of a ruptured aortic aneurysm carries a very high morbidity and mortality rate. All patients who are hypotensive and have a a pulsatile mass should be evaluated in the OR. US is portable, senstive, and readily available.

What is the major cause of morbidity and mortality in patients with significant total body surface area burns?

Hypovolemic shock. In the setting of adequate initial fluid resuscitation, bacterial infection (usually bronchopneumonia or burn wouund infection) leading to sepsis and septic shock is the leading complication.

Major complication of an infection in the parapharygneal space?

involvement of the carotid sheath, which may lead to erosion of the carotid artery and jugular thromobophlebiits.

hypermetabolic phase of burns

In the days following a severe burn injury, significant increases in circulating catecholamines and cortisol cause significant protein losses as muscle degradation is used for gluconeogenesis. This increased protein breakdown is a normal part of the burn wound response known as hypermetabolic phase. This phase is typically associated with an elevated cardiac output and does not itself cause hypotension.

Ludwig's angina

Infection in the submandibular space. Typically begins in the floor of the mouth and extends through the submandibular and sublingual space into the tissues surrounding the airway. It does not commonly extend into the mediastinum

Acute cholecystitis managmenet

It is appropriate to manage acute cholecystitis conservatively followed by cholecystectomy within 72 hours. Symptoms often subside within a few days with volume resuscitation, antibiotics, and pain medications. Early cholecystecomy (within 72 hours) reduces disease duration, duration of hospitialization, and cholecystitis-associated mortality when compared to delayed cholecystectomy. Laparoscopic cholecystectomy is the surgical producedure of choice in patients w/o contraindications. US is more sensitive than CT scan for making the dx of acute cholecystitis. Acute cholecystitis presens with RUQ pain, fever, and leukocytosis. THe majority of patients with acute cholecystitis may be treated with observation and supportive care initially, followed by laproscopic cholecystectomy within 72 hours during the same hospitalization.

Laryngeal mask placement; nastotrachal intubation, needle cricothyrodisitomy and trahesostomy in cervical spine injury??

Laryngeal mask placement is a temporary measure to stabilize the patient until another airway can be established if orotracheal intubation fails. Nasotracheal intubation is a blind procedure that is contraindicated in apneic/hypopneic patients. It is also contraindicated if the patient has a basilar skull fracture as such fractures are associated with a risk of cribriform plate disruption, which could lead to inadvertent intracrnail passage of the tube. Due to the risk of CO2 retention, needle cricothyrodotomy is not ideal in patients wit head injury who might require hyperventilation to prevent or treat intracranial HTN. However, it is preferred to surgical cricothyorodimoty in children <12 as it is easier to perform anatomically. Tracheostomy is no longer a first option for establishing an airway due to its complications. Surgical cricothyrodotomy is preferred over surgical trahceostomy but should be converted to formal trahceostomy in 5-7 days if prolonged airway control is needed. Prolonged use of cricothyroidotmy has a high incidence of tracheal stenosis.

What side is diaphragmatic rupture more common?

Left side bc the right side tends to be protected by the liver. Pts can acutely present with respiratory distress, but some patients with smaller ruptures can have a delayed presentation with nausea and vomiting. Elevation of the hemidiaphragm on the CXR might be the only abnormal finding, but ultrasonography or CT scan of the chest is sometimes required if the CXR does not visualize the area well. The small bowel is sometimes present in the thoracic cavity.

Marfan's syndrome and aortic dissection?

Marfan's syndrome is caused by a mutation of the fibrillin gene, which results in "weakened" connective tissue. Patients with Marfan's syndrome are at increased risk for aortic dissection. However, marfan's syndrome is not the strongest risk factor, and tends to cause aortic dissection in younger patients.

Delayed hemolytic transfusion rxn

Mild fever and hemolytic anemia. Within 2-10 days after transfusion. Positive direct Coombs test, positive new Ab screen. Caused by anamnestic antibody response.

Aortic rupture and death

Most patients with aortic rupture die in the field. Those that survive to the ED typically have suffered an injury of the aorta just distal to the left subclavian artery that may be contained as hematomas within the mediastium. This form of aortic rupture tyically causes hypertension (due to visceral afferent reflexes and a pseudocoarctation syndrome) and not JVD

Management of cervical spine trauma in the ED

Orotracheal intubation preferred unless significant facial trauma present. Rapid-sequence intubation added for unconscious who are breathing but need ventilatory support. In-line cervical stabilization suggested unless it interferes with intubation. CT of entire cervical spine. Monitoring for neurogenic shock from spinal cord injury.

PE presentation? Tense pneumonthorax presentation?

PE: pleuritic chest pain, dyspnea, and typically anormal CXR. Tension pneumo likely to cause hypotension.

Burns and SIRS

Patients with severe burns usually manifest some evidence of SIRS and also have a hypermetabolic response in the first week after the burn. This response includes hyperglycemia (due to insulin resistance), muscle wasting, protein loss, hyperthermia, and increased energy expenditure. Another life-threatening complication of severe burns in the first week is infection leading to sepsis and septic shock, and the main causes are pneumonia and wound infections (from staph aureus or pseudomonas aeruginoma). Ex: criteria that indicate sepsis in ex patient include worsening hyperglycemia (due to worsening insulin resistance), leukocytosis, thrombocyotpenia, mild hypothermia (temperature <36C), tachypnea, and tachycardia

positive pressure ventilation in untreated tension pneumothorax?

Positive pressure ventilation in a patient with untreated TP may exacerbate the "one-way-valve" effect, furhter increasing intrathorracic pressures and worsening hemodyanmic collapse. Emergency chest decompression with needle thoracstomy is diagnostic and life saving. Typically 14-16 gauge IV cannula inserted in 2nd intercostal space (btwn 2nd and 3rd ribs) at the MCL to relieve the pneumohtorax. An immediate rush of air out of the chest cavity indicates TP. A standard thoracostomy must be performed following needle decompression to relieve the ensuing pneumothorax

Compartment syndrome

can be acute or chronic and usually presents with pain in a specific muscle region that occurs at the onset of exercise and decreases with rest. Unlike a stress fracture, there is no point tenderness on the bone, and the pain mainly occurs with exercise rather than all activities

Malignant hyperthermia

caused by inhaled anesthetics and typically occurs intraoperatively or in the immediate postoperative period. Patients usually have fever, tachycardia, acidosis, and rhabdomyolis and are at high risk for cardiac arrest and death.

Arterial occlusion of an extremity vs embolic occlusion

causes pain, pulselessness, pallor, paesthesias and paralysis in the affected limb. Embolic occlusion classically causes sudden-onset severe pain and asymmetric pulselessness.

Diaphragmatic rupture

more common on the left side bc the right side tends to be protected by the liver. Patients usually have respiratory distress and can have deviation of the mediastinal contents to the opposite side. Elevation of the hemidiaphragm on the CXR might be the only abnormal finding. CXR showing a nasogastric tube in the pulmonary cavity is diagnostic.

Anaphylatic transfusion rxn

Rapid onset of shock, angioedema/urticaria and respiratory distress. Within a few seconds to minutes of transfusion. Caused by recipient anti-IgA antibodies

Transfusion-related acute lung injury

Respiratory distress and signs of noncardiogenic pulmonary edema. Within 6 hours of transfusion. Caused by donor anti-leukocyte antibodies.

What are classic causes of acute renal failure (eg, tubular necrosis)?

Shock and hypotension. (renal failure itself typically does NOT induce shock or hypotension)

Management of cervical spine trauma prehospital

Spinal immobilization (eg, backboard, right cervical collar, lateral head supports). Careful helmet removal (eg, motocycle helmet). Airway oxygenation.

Factors that favor infection over contamination

Systemic signs, such as fever, hypotension, or leukocytosis. Erythema and tenderness at the catheter entry site (the absence local signs does not rule out an infection). Culture growth within 48 hours and in both aerobic and anaerbic bottles. Two or more blood culture samples with the same organism and drug susceptibility

SIRS criteria

Temperature >38.5C (101.3F) or <35 (95F); pulse >90/min; respirations >20/min. WBC >12,000 cells/mm3, <4000 cells/mm3, or >10% bands. SIRS is defined as having at least 2 of the 4 critiera. It can occur in conditions such as pancreatitis, autoimmune disease, vasculitis, and burns. Sepsis (SIRS with a known infection) is considered severe when there is associated end-organ dysfunction, such as oliguria, hypotension (ie, systolic <90 mmHg), thrombocytopenia (ie, platelet count <80,000/mm3), metabolic acidosis, or hypoxemia.

Early recognition of diaphragmatic trauma

is extremely important bc the mortality rate of undiagnosed injury and subsequent strangulation of the bowel can be 30-70% depending on the extent of the associated injuries. Most patiens require surgical repair and exploration of the abdomen for other traumatic injuries. CXR showing NG tube in the pulmonary cavity, indicates a diaphragmatic hernia. Surgical reapir needed.

Teratomas

The differential diagnosis for an anterior mediastinal mass includes the 4 T's: thymoma, teratoma, thyroid neoplasm, and terrible lymphoma. Within the category of teratoma, one must also include other germ cell tumors. Teratomas can often be distinguished from other germ cell tumors on imaging by the presence of fat or calcium, particularly if in the form of a tooth. Serum hormone levels may be helpful in differentiating seminomatous germ cell tumors from nonseminomatous variants. Serum B-HCG can be elevated in 1/3 of patients with seminoma, although the AFP is essentially always normal. Nonseminamatous forms of germ cell tumors include yolk sac tumor, choriocarcinoma, and embroyonal carcinoma. A mixture of different cell types is also possible and is referred to as a mixed germ cell tumor. Most patients with a nonseminomatous germ cell tumor have an elevated AFP, with a considerable amount also having an elevated B-HCG.

Sublingual space

The sublingual space is a division of the submandibular space. As a result, an infection in the sublingual space is classified as a submandibular infection as well, which typically involves the tongue, palate, pharynx, epiglottis, and tissues surronding the upper airway

Bicuspid aortic valve and aortic dissection (AD)? Giant cell artereits? DM? ATH? pHTN?

There's an association btwn having a bicuspid aortic valve and developing aortic dissection, even in patients who do not develop aortic stenosis and post-stenotic aortic dilation secondary to the valve abnormality. However, HTN is a much more common cause. Though giant cell artereitis involves large vessels, it is more comon in the cranial branches of the aortic arch and is only rarely associated with AD. DM is not strongly associated with AD, except in indivduals where there is concomitant HTN. ATH is a risk factor for development of thoracic aortic aneurysms, which themselves predispose to AD. However, HTN has a far stronger association with AD. pHTN is not associated with AD.

Tibia and stress fractures

Tibia = major weight-bearing bone in the leg, and patients usually develop medial tibial stress syndrome (ie "shin splints" with no tibial tenderness on palpation). This can progress with further activity to a complete or incomplete fracture, resulting in pain to palpation of the tibia. The dx of a stress fracture is clinically made on examination with pain at a specific area that increases with jumping or running and is associated with local swelling and point tenderness to palpation. X-rays are frequently normal but can reveal periosteal reaction in the site of the fracture. The injury is best defined radiographically using MRI or bone scan. Tx invovles rest and healing of the stress fracture.

What is the most common bone in the body to be affected by stress fractures?

Tibia. Stress fractures classically occur in the anterior part of the middle third of the tibia in patients involved in jumping sports and the posteromedial part of the distal third of the tibia in runners. X-rays are frequently normal during initial evaluation.

Prosthetic joint infection delayed-onset infection

Timing: >3 months after primary athrtoplasty. Presentation: Persistent joint pain, implant loosening or sinus tract formation. Most common organisms: coagulase-negative staphylococci (ie staph epidermidis), Propionibacterium species, enterococci. Mgmt: Implant removal/exchange generally recommended

Prosthetic joint infection early onset-infection

Timing: within 3 months of primary arhtroplasty. Presentation: wound drainage, erythema, swelling often with fever. Most common organisms: Staphylococcus aureus, Gram negative rods, anaerobes. Mgmt: inplant removal/exchange, may consider debridement and implant retention

Urticarial/allergic transfusion rxn

Urticaria, flushing, angioedema, and pruritis. Within 2-3 hours of transfusion. Caused by recipient IgE antibodies and mast cell activation.

Endoscopic retrograde cholangiography (ERCP)

Uses a fiberoptic camera and fluoroscopy to visualize the biliary and pancreatic ducts for diagnostic and therapeutic purposes. It would be reasonable to perform ERCP if patient has choledocholithias or a gallstone in the common biliary duct (CBD) causing CBD dilation. In such cases, sphincterotomy can help facilitate passage of stones.

Causes of postoperative fever (the 5Ws)

Wind (lungs): pulmonary embolus, pneumonia, aspiration. Wound: surgical site infection. Water: UTI. Walk: DVT. Wonder drugs/products: drug fever, blood products, IV lines.

Sepsis

a clinical syndrome characterized by systemic inflammation and tissue injury. There is usually an original insult (eg, infection and injury) that leads to inflammation and a dysregulated host reponse, with a massive and uncontrolled release of proinflammatory substances causing extensive tissue damage. This response to an infection is referred to as sepsis, while noninfectious causes are known as systemic inflammatory response syndrome (SIRS)

Uncomplicated diverticulitis

characterized by colonic diverticular inflammation resulting in LLQ pain and tenderness, fever, and leukocytosis. A CT scan can show associated inflammation as soft tissue stranding and colonic wall thickening. Uncomplicated diveritculitis in stable patients can be managed in the outpatient setting with bowel rest, oral antibiotics, and observation. Hospitilization, tx with IV broad-spectrum abx, and observation is recommended for patients who are elderly, are immunosuppressed, have high fever, or significant leukocytosis, and with significant comorbidities

Radiation proctitis

characterized clinically by diarrhea, rectal bleeding, tenesmus and incontinenece. Later, strictures and fistulae may form.

Clostridium difficile colitis (pseudomembranous colitis)

abdominal pain, fever and watery diarrhea. Dx can be confimed with colonoscopy or, more commonly, by detecting toxin in the stool with ELISA

Inflammatory bowel disease vs colonic ischemia

acute onset of colonic ischemia and have different apperance on colonoscopy. Namely, ischemia typically spares the rectum and involves only a segment of the colon while IBD does not

Acute diverticulitis

an acute inflammation of the colonic wall that can be classified as uncomplicated (75%) or complicated (25%)

Coag negative staphlococci

are the most frequent cause of nosocomial bloodstream infection in patients with intravascular devices. Factors favoring infection over contamination include fever, leukocytosis, hypotension, and blood culture growth in >/= 2 bottles (both aerobic and anarobic) with the same organism and drug susceptiblity

arterial vasculitis

arterial vasculitis of any cause will typically be accompanied by constitutional symptoms such as fever, malaise, and weight loss as well as other systemic findings specific to each vasculitic syndrome. Examples of arterial vasculitis: Takayasu arteritis, polyarteritis nodosa, temporal arteritis, Churg-Strauss disease and others

Complicated diverticulitis

diverticulitis associated with an abscess, perforation, obstruction, or fistula formation. Fluid collection <3 cm can be treated with IV abx and observation, with surgery reserved for patients with worsening symptoms. Fluid collection >3 cm should initially be drained with CT-guided drainage. If the drain does not control symptoms by the 5th day, surgery for drainage and debridement is the next recommended step. Surgery with sigmoid resection is generally reserved for patients with fistulas, perforation with peritonitis, obstruction, or recurrent attacks of diverticulitis. Ex: patient with 5cm fluid collection: should first have CT-guided drainage and then surgery if the drain fails.

Perianal fistual

due to chronic anal crypt infection or Chron's dz have an external (cutaneous) opening draining purlent material. Perianal fistuael are generally located within 3cm of the anal margin

Serum sickness

fever, urticaria, arthritis, and nephritis. Usually results from an immune complex reaction against heterologous proteins

Cardiac tamponade presentation

hypotension, distended neck veins, and tachycardia. CXR tends to show a globular cardiac silhouette.

Indwelling urinary catheters

increase the risk for UTI with enteric organisms such as E Coli, Klebsiella pneumoniae, and Proteus mirabilis. Staphylococcus saprophyticus (coagulase negative staphylococci) is a common cause of uncomplicated acute cystitis in young, sexually active women.

Acute cholecystitis

inflammation and distension of the gallbladder, typically due to obstruction of the cystic duct by a gallstone. Presents with acute right upper quadrant pain and tenderness, plus fever, and leukocytosis. Physical examination may reveal a positive Murphy's sign. The gallbladder is palpable in one-third of cases.

PE presentation

pleuritic chest pain, dyspnea, tachypnea, tachycardia, and possibly hemotypsis

Perianal abscess

presents with anal pain and a tender, eryhtemaotus bulge at the anal verge.

Wrist immobilization

recommended in the tx of all nondisplaced scaphoid fractures (fractures with <2 mm of displacement and no angulation)

arterial thrombosis

results in slow, progressive narrowing of the vascular lumen in the affected limb. Thus, the symptoms have an insidious onset. Additionally, the pulses in patients with arteial thromobiss are usually diminished bilaterally.

What is the most feared complication of a retropharyngeal abscess?

spread of infection into the mediastium, which can lead to acute necrotizing mediastinitis

Bowen's disease

squamous cell carcinoma in situ of the skin. typically presents as a thin eryhtmeouats plaque with well-defined irregular borders and an overlying scale or crust

Acute aortic dissection

sudden, tearing pain that radiates to the back. The decrescendo diastolic murmur heard: aortic regurgitation, which can be a consequence of aortic dissection involving the aortic root. Classic CXR: widened mediastinum (seen in ~60% of pts). Variety of risk factors for development of aortic dissection, but the most common = HTN (seen in ~75% of cases). Aortic dissection causes chest pain: sudden, tearing, and radiating to the back. HTN is the most common predisposing factor.

Fracture of the right scaphoid bone

the scaphoid bone is the most commonly fractured bone among the carpals. Scaphoid fractures are commonly seen in young adults following a fall on the outstretched hand. Patients generally complain of pain at the wrist joint. Tenderness in the anatomic snuffbox is a very sensitive marker of scaphoid fracture. A scaphoid fracture is most commonly located across the waist of the scaphoid bone. Iniital x-rays can be normal or show fine radiolucent lines in nondisplaced scaphoid fractures (fractures with <2mm of displacement and no angulation). Scaphoid views are necessary to avoid missing the fractures. Wrist immobilization (for 6-10 weeks) is recommended in the tx of all nondisplaced scaphoid fractures. The wrist should be immobilized in all proven or suspected scaphoid fracures due to the risk of nonunion. If the initial x-rays are negative in a patient with suspected scaphoid fracture, further management should be immbolization with subsequent x-ray in 7-10 days or immediate advanced imaging (eg CT scan)

Drug fever

typically a dx of exclusion. It is often associated with use of anticonvulsants, antibiotics (beta-lactams, sulfonamides), or allopurinol. Most cases of drug fever occur 1-2 weeks after initiation of therapy.

Flail chest

typically caused by three or more adjacent rib fractures that break in 2 places and create an unstable chest wall segment that moves in a paradoxic motion with respiration. The segment tends to contraction during inspiration (normally bulges out) and bulge out during expiration (normally retracts)

venous thrombosis (DVT)

typically causes pain and edema of the lower extremity and may be accompanied by warmth to touch. The pain is typically dull and aching in contrast to the sudden and severe pain above arterial embolism of leg. Pulselessness is NOT a feature of DVT

bone neoplasms

typically present with pain and tenderness and can be complicated by pathologic fractures. Metastases to the bone are more common than are primary tumors and typically affect the axial skeleton or proximal humerus and femur. Radiographic evidence of bone destruction or tumor is usually evident on x-ray in these cases

Osteomyelitis presentation

typically presents with both systemic (fever) and local findings (tenderness, warmth, erythema, and swelling)

Nerve entrapment

typically presents with radiating pain and is not typically reproducible with palpation.

Percutaneous transhepatic gallbladder drainage

used to decompress the gallbladder in patients who are unstable or have a contraindication to surgery.

Aortic rupture

usually results in instantaneous death. Rarely patients may present with profound hypotension and CXR usually shows widened mediastinum. It is less likely in a hemodynamically stable patient.

Hypothyroidism manifestations

weakness, cold intolerane, constipation, depression, menorrhagia, hoarseness, dry skin, bradycardia, and myxedema